Update version

fails only when FMT_BUILTIN_CTZLL is not defined

.clang-format

@@ -0,0 +1,8 @@
+# Run manually to reformat a file:
+# clang-format -i --style=file <file>
+Language: Cpp
+BasedOnStyle: Google
+IndentPPDirectives: AfterHash
+IndentCaseLabels: false
+AlwaysBreakTemplateDeclarations: false
+DerivePointerAlignment: false

.gitignore

@@ -1,4 +1,5 @@
 .vscode/
+.vs/
 
 *.iml
 .idea/
@@ -14,6 +15,7 @@ bin/
 /CMakeScripts
 /doc/doxyxml
 /doc/html
+/doc/node_modules
 virtualenv
 /Testing
 /install_manifest.txt

.travis.yml

@@ -7,7 +7,6 @@ os: linux
 git:
   depth: 1
 
-
 env:
   global:
     - secure: |-
@@ -39,6 +38,26 @@ matrix:
             - ubuntu-toolchain-r-test
           packages:
             - g++-6
+     # g++ 8 on Linux with C++17
+    - env: COMPILER=g++-8 BUILD=Debug STANDARD=17
+      compiler: gcc
+      addons:
+        apt:
+          update: true
+          sources:
+            - ubuntu-toolchain-r-test
+          packages:
+            - g++-8
+    - env: COMPILER=g++-8 BUILD=Release STANDARD=17
+      compiler: gcc
+      addons:
+        apt:
+          update: true
+          sources:
+            - ubuntu-toolchain-r-test
+          packages:
+            - g++-8
+
       # Apple clang on OS X with C++14
     - env: BUILD=Debug STANDARD=14
       compiler: clang
@@ -46,8 +65,8 @@ matrix:
     - env: BUILD=Release STANDARD=14
       compiler: clang
       os: osx
-      # clang 6.0 on Linux with C++14
-    - env: COMPILER=clang++-6.0 BUILD=Debug STANDARD=14
+      # clang 6.0 on Linux with C++14 (builds the fuzzers as well)
+    - env: COMPILER=clang++-6.0 BUILD=Debug STANDARD=14 ENABLE_FUZZING=1
       compiler: clang
       addons:
         apt:
@@ -73,52 +92,6 @@ matrix:
       # g++ 4.8 on Linux with C++11
     - env: COMPILER=g++-4.8 BUILD=Debug STANDARD=11
       compiler: gcc
-      # g++ 4.4 on Linux with C++11
-    - env: COMPILER=g++-4.4 BUILD=Debug STANDARD=11
-      compiler: gcc
-      addons:
-        apt:
-          update: true
-          packages:
-            - g++-4.4
-          sources:
-            - ubuntu-toolchain-r-test
-      # Android
-    - language: android
-      addons:
-        apt:
-          update: true
-          sources:
-            - ubuntu-toolchain-r-test
-          packages:
-            - wget
-            - unzip
-            - tree
-      android:
-        components:
-          - tools
-          - platform-tools
-          - android-21
-      env:
-        - ANDROID=true
-      before_install:
-        # Download/Install Gradle 
-        - wget https://services.gradle.org/distributions/gradle-4.10.2-bin.zip
-        - mkdir -p gradle
-        - unzip -q -d ./gradle gradle-4.10.2-bin.zip
-        - export GRADLE=gradle/gradle-4.10.2/bin/gradle
-        - bash $GRADLE --version
-      install:
-        # Accept SDK Licenses + Install NDK
-        - yes | sdkmanager --update > /dev/null 2>&1
-        - sdkmanager ndk-bundle > /dev/null 2>&1
-      before_script:
-        - pushd ./support
-      script:
-        - bash ../$GRADLE clean assemble
-      after_success:
-        - popd;
-        - tree ./libs
 
 before_script:
   - if [[ "${TRAVIS_OS_NAME}" == "linux" ]]; then export CXX=${COMPILER}; fi

CMakeLists.txt

@@ -1,10 +1,8 @@
-cmake_minimum_required(VERSION 3.1.0)
+cmake_minimum_required(VERSION 3.1...3.18)
 
-# Use newer policies if available, up to most recent tested version of CMake.
-if(${CMAKE_VERSION} VERSION_LESS 3.11)
+# Fallback for using newer policies on CMake <3.12.
+if(${CMAKE_VERSION} VERSION_LESS 3.12)
   cmake_policy(VERSION ${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION})
-else()
-  cmake_policy(VERSION 3.11)
 endif()
 
 # Determine if fmt is built as a subproject (using add_subdirectory)
@@ -24,24 +22,51 @@ function(join result_var)
   set(${result_var} "${result}" PARENT_SCOPE)
 endfunction()
 
+include(CMakeParseArguments)
+
+# Sets a cache variable with a docstring joined from multiple arguments:
+#   set(<variable> <value>... CACHE <type> <docstring>...)
+# This allows splitting a long docstring for readability.
+function(set_verbose)
+  # cmake_parse_arguments is broken in CMake 3.4 (cannot parse CACHE) so use
+  # list instead.
+  list(GET ARGN 0 var)
+  list(REMOVE_AT ARGN 0)
+  list(GET ARGN 0 val)
+  list(REMOVE_AT ARGN 0)
+  list(REMOVE_AT ARGN 0)
+  list(GET ARGN 0 type)
+  list(REMOVE_AT ARGN 0)
+  join(doc ${ARGN})
+  set(${var} ${val} CACHE ${type} ${doc})
+endfunction()
+
 # Set the default CMAKE_BUILD_TYPE to Release.
 # This should be done before the project command since the latter can set
 # CMAKE_BUILD_TYPE itself (it does so for nmake).
-if (NOT CMAKE_BUILD_TYPE)
-  join(doc "Choose the type of build, options are: None(CMAKE_CXX_FLAGS or "
-           "CMAKE_C_FLAGS used) Debug Release RelWithDebInfo MinSizeRel.")
-  set(CMAKE_BUILD_TYPE Release CACHE STRING ${doc})
+if (MASTER_PROJECT AND NOT CMAKE_BUILD_TYPE)
+  set_verbose(CMAKE_BUILD_TYPE Release CACHE STRING
+              "Choose the type of build, options are: None(CMAKE_CXX_FLAGS or "
+              "CMAKE_C_FLAGS used) Debug Release RelWithDebInfo MinSizeRel.")
 endif ()
 
+project(FMT CXX)
+include(GNUInstallDirs)
+set_verbose(FMT_INC_DIR ${CMAKE_INSTALL_INCLUDEDIR} CACHE STRING
+            "Installation directory for include files, a relative path that "
+            "will be joined with ${CMAKE_INSTALL_PREFIX} or an absolute path.")
+
 option(FMT_PEDANTIC "Enable extra warnings and expensive tests." OFF)
-option(FMT_WERROR "Halt the compilation with an error on compiler warnings." OFF)
+option(FMT_WERROR "Halt the compilation with an error on compiler warnings."
+       OFF)
 
 # Options that control generation of various targets.
 option(FMT_DOC "Generate the doc target." ${MASTER_PROJECT})
 option(FMT_INSTALL "Generate the install target." ${MASTER_PROJECT})
 option(FMT_TEST "Generate the test target." ${MASTER_PROJECT})
-
-project(FMT)
+option(FMT_FUZZ "Generate the fuzz target." OFF)
+option(FMT_CUDA_TEST "Generate the cuda-test target." OFF)
+option(FMT_OS "Include core requiring OS (Windows/Posix) " ON)
 
 # Get version from core.h
 file(READ include/fmt/core.h core_h)
@@ -58,24 +83,35 @@ message(STATUS "Version: ${FMT_VERSION}")
 
 message(STATUS "Build type: ${CMAKE_BUILD_TYPE}")
 
-set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
+if (NOT CMAKE_RUNTIME_OUTPUT_DIRECTORY)
+  set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
+endif ()
 
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH}
   "${CMAKE_CURRENT_SOURCE_DIR}/support/cmake")
 
 include(cxx14)
 include(CheckCXXCompilerFlag)
+include(JoinPaths)
+
+list(FIND CMAKE_CXX_COMPILE_FEATURES "cxx_variadic_templates" index)
+if (${index} GREATER -1)
+  # Use cxx_variadic_templates instead of more appropriate cxx_std_11 for
+  # compatibility with older CMake versions.
+  set(FMT_REQUIRED_FEATURES cxx_variadic_templates)
+endif ()
+message(STATUS "Required features: ${FMT_REQUIRED_FEATURES}")
 
 if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
   set(PEDANTIC_COMPILE_FLAGS -pedantic-errors -Wall -Wextra -pedantic
       -Wold-style-cast -Wundef
       -Wredundant-decls -Wwrite-strings -Wpointer-arith
       -Wcast-qual -Wformat=2 -Wmissing-include-dirs
-      -Wcast-align -Wnon-virtual-dtor
+      -Wcast-align
       -Wctor-dtor-privacy -Wdisabled-optimization
       -Winvalid-pch -Woverloaded-virtual
-      -Wconversion
-      -Wno-ctor-dtor-privacy -Wno-format-nonliteral -Wno-shadow)
+      -Wconversion -Wswitch-enum -Wundef
+      -Wno-ctor-dtor-privacy -Wno-format-nonliteral)
   if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.6)
       set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wnoexcept
          -Wno-dangling-else -Wno-unused-local-typedefs)
@@ -93,7 +129,8 @@ if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
 endif ()
 
 if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
-  set(PEDANTIC_COMPILE_FLAGS -Wall -Wextra -pedantic -Wconversion -Wno-sign-conversion)
+  set(PEDANTIC_COMPILE_FLAGS -Wall -Wextra -pedantic -Wconversion -Wundef
+      -Wdeprecated -Wweak-vtables)
   check_cxx_compiler_flag(-Wzero-as-null-pointer-constant HAS_NULLPTR_WARNING)
   if (HAS_NULLPTR_WARNING)
     set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS}
@@ -117,17 +154,24 @@ if (MASTER_PROJECT AND CMAKE_GENERATOR MATCHES "Visual Studio")
     set(MSBUILD_SETUP "call \"${WINSDK_SETENV}\"")
   endif ()
   # Set FrameworkPathOverride to get rid of MSB3644 warnings.
-  set(netfxpath "C:\\Program Files\\Reference Assemblies\\Microsoft\\Framework\\.NETFramework\\v4.0")
+  join(netfxpath
+       "C:\\Program Files\\Reference Assemblies\\Microsoft\\Framework\\"
+       ".NETFramework\\v4.0")
   file(WRITE run-msbuild.bat "
     ${MSBUILD_SETUP}
     ${CMAKE_MAKE_PROGRAM} -p:FrameworkPathOverride=\"${netfxpath}\" %*")
 endif ()
 
+set(strtod_l_headers stdlib.h)
+if (APPLE)
+  set(strtod_l_headers ${strtod_l_headers} xlocale.h)
+endif ()
+
 include(CheckSymbolExists)
 if (WIN32)
-  check_symbol_exists(open io.h HAVE_OPEN)
+  check_symbol_exists(_strtod_l "${strtod_l_headers}" HAVE_STRTOD_L)
 else ()
-  check_symbol_exists(open fcntl.h HAVE_OPEN)
+  check_symbol_exists(strtod_l "${strtod_l_headers}" HAVE_STRTOD_L)
 endif ()
 
 function(add_headers VAR)
@@ -139,17 +183,28 @@ function(add_headers VAR)
 endfunction()
 
 # Define the fmt library, its includes and the needed defines.
-add_headers(FMT_HEADERS chrono.h color.h core.h format.h format-inl.h locale.h
-                        ostream.h printf.h time.h ranges.h)
-set(FMT_SOURCES src/format.cc)
-if (HAVE_OPEN)
-  add_headers(FMT_HEADERS posix.h)
-  set(FMT_SOURCES ${FMT_SOURCES} src/posix.cc)
+add_headers(FMT_HEADERS chrono.h color.h compile.h core.h format.h format-inl.h
+                        locale.h os.h ostream.h posix.h printf.h ranges.h)
+if (FMT_OS)
+  set(FMT_SOURCES src/format.cc src/os.cc)
+else()
+  set(FMT_SOURCES src/format.cc)
 endif ()
 
 add_library(fmt ${FMT_SOURCES} ${FMT_HEADERS} README.rst ChangeLog.rst)
 add_library(fmt::fmt ALIAS fmt)
 
+if (HAVE_STRTOD_L)
+  target_compile_definitions(fmt PUBLIC FMT_LOCALE)
+endif ()
+
+if (MINGW)
+  check_cxx_compiler_flag("Wa,-mbig-obj" FMT_HAS_MBIG_OBJ)
+  if (${FMT_HAS_MBIG_OBJ})
+    target_compile_options(fmt PUBLIC "-Wa,-mbig-obj")
+  endif()
+endif ()
+
 if (FMT_WERROR)
   target_compile_options(fmt PRIVATE ${WERROR_FLAG})
 endif ()
@@ -157,62 +212,78 @@ if (FMT_PEDANTIC)
   target_compile_options(fmt PRIVATE ${PEDANTIC_COMPILE_FLAGS})
 endif ()
 
+target_compile_features(fmt INTERFACE ${FMT_REQUIRED_FEATURES})
+
 target_include_directories(fmt PUBLIC
   $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
-  $<INSTALL_INTERFACE:include>)
+  $<INSTALL_INTERFACE:${FMT_INC_DIR}>)
+
+set(FMT_DEBUG_POSTFIX d CACHE STRING "Debug library postfix.")
 
 set_target_properties(fmt PROPERTIES
   VERSION ${FMT_VERSION} SOVERSION ${CPACK_PACKAGE_VERSION_MAJOR}
-  DEBUG_POSTFIX d)
+  DEBUG_POSTFIX "${FMT_DEBUG_POSTFIX}")
+
+# Set FMT_LIB_NAME for pkg-config fmt.pc. We cannot use the OUTPUT_NAME target
+# property because it's not set by default.
+set(FMT_LIB_NAME fmt)
+if (CMAKE_BUILD_TYPE STREQUAL "Debug")
+  set(FMT_LIB_NAME ${FMT_LIB_NAME}${FMT_DEBUG_POSTFIX})
+endif ()
 
 if (BUILD_SHARED_LIBS)
-  if (UNIX AND NOT APPLE)
+  if (UNIX AND NOT APPLE AND NOT ${CMAKE_SYSTEM_NAME} MATCHES "SunOS" AND
+      NOT EMSCRIPTEN)
     # Fix rpmlint warning:
     # unused-direct-shlib-dependency /usr/lib/libformat.so.1.1.0 /lib/libm.so.6.
     target_link_libraries(fmt -Wl,--as-needed)
   endif ()
   target_compile_definitions(fmt PRIVATE FMT_EXPORT INTERFACE FMT_SHARED)
 endif ()
+if (FMT_SAFE_DURATION_CAST)
+  target_compile_definitions(fmt PUBLIC FMT_SAFE_DURATION_CAST)
+endif()
 
 add_library(fmt-header-only INTERFACE)
 add_library(fmt::fmt-header-only ALIAS fmt-header-only)
 
 target_compile_definitions(fmt-header-only INTERFACE FMT_HEADER_ONLY=1)
+target_compile_features(fmt-header-only INTERFACE ${FMT_REQUIRED_FEATURES})
 
 target_include_directories(fmt-header-only INTERFACE
   $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
-  $<INSTALL_INTERFACE:include>)
+  $<INSTALL_INTERFACE:${FMT_INC_DIR}>)
 
 # Install targets.
 if (FMT_INSTALL)
-  include(GNUInstallDirs)
   include(CMakePackageConfigHelpers)
-  set(FMT_CMAKE_DIR ${CMAKE_INSTALL_LIBDIR}/cmake/fmt CACHE STRING
-    "Installation directory for cmake files, relative to ${CMAKE_INSTALL_PREFIX}.")
+  set_verbose(FMT_CMAKE_DIR ${CMAKE_INSTALL_LIBDIR}/cmake/fmt CACHE STRING
+              "Installation directory for cmake files, a relative path that "
+              "will be joined with ${CMAKE_INSTALL_PREFIX} or an absolute "
+              "path.")
   set(version_config ${PROJECT_BINARY_DIR}/fmt-config-version.cmake)
   set(project_config ${PROJECT_BINARY_DIR}/fmt-config.cmake)
   set(pkgconfig ${PROJECT_BINARY_DIR}/fmt.pc)
   set(targets_export_name fmt-targets)
 
-  set (INSTALL_TARGETS fmt)
-  if (TARGET fmt-header-only)
-    set(INSTALL_TARGETS ${INSTALL_TARGETS} fmt-header-only)
-  endif ()
+  set_verbose(FMT_LIB_DIR ${CMAKE_INSTALL_LIBDIR} CACHE STRING
+              "Installation directory for libraries, a relative path that "
+              "will be joined to ${CMAKE_INSTALL_PREFIX} or an absolute path.")
 
-  set(FMT_LIB_DIR ${CMAKE_INSTALL_LIBDIR} CACHE STRING
-      "Installation directory for libraries, relative to ${CMAKE_INSTALL_PREFIX}.")
-
-  set(FMT_INC_DIR ${CMAKE_INSTALL_INCLUDEDIR}/fmt CACHE STRING
-      "Installation directory for include files, relative to ${CMAKE_INSTALL_PREFIX}.")
-
-  set(FMT_PKGCONFIG_DIR "${CMAKE_INSTALL_PREFIX}/share/pkgconfig" CACHE PATH
-    "Installation directory for pkgconfig (.pc) files, relative to ${CMAKE_INSTALL_PREFIX}.")
+  set_verbose(FMT_PKGCONFIG_DIR ${CMAKE_INSTALL_LIBDIR}/pkgconfig CACHE PATH
+              "Installation directory for pkgconfig (.pc) files, a relative "
+              "path that will be joined with ${CMAKE_INSTALL_PREFIX} or an "
+              "absolute path.")
 
   # Generate the version, config and target files into the build directory.
   write_basic_package_version_file(
     ${version_config}
     VERSION ${FMT_VERSION}
     COMPATIBILITY AnyNewerVersion)
+
+  join_paths(libdir_for_pc_file "\${exec_prefix}" "${FMT_LIB_DIR}")
+  join_paths(includedir_for_pc_file "\${prefix}" "${FMT_INC_DIR}")
+
   configure_file(
     "${PROJECT_SOURCE_DIR}/support/cmake/fmt.pc.in"
     "${pkgconfig}"
@@ -221,6 +292,8 @@ if (FMT_INSTALL)
     ${PROJECT_SOURCE_DIR}/support/cmake/fmt-config.cmake.in
     ${project_config}
     INSTALL_DESTINATION ${FMT_CMAKE_DIR})
+
+  set(INSTALL_TARGETS fmt fmt-header-only)
   # Use a namespace because CMake provides better diagnostics for namespaced
   # imported targets.
   export(TARGETS ${INSTALL_TARGETS} NAMESPACE fmt::
@@ -235,10 +308,13 @@ if (FMT_INSTALL)
 
   # Install the library and headers.
   install(TARGETS ${INSTALL_TARGETS} EXPORT ${targets_export_name}
-          DESTINATION ${FMT_LIB_DIR})
+          LIBRARY DESTINATION ${FMT_LIB_DIR}
+          ARCHIVE DESTINATION ${FMT_LIB_DIR}
+          RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
 
-  install(FILES $<TARGET_PDB_FILE:${INSTALL_TARGETS}> DESTINATION ${FMT_LIB_DIR} OPTIONAL)
-  install(FILES ${FMT_HEADERS} DESTINATION ${FMT_INC_DIR})
+  install(FILES $<TARGET_PDB_FILE:${INSTALL_TARGETS}>
+          DESTINATION ${FMT_LIB_DIR} OPTIONAL)
+  install(FILES ${FMT_HEADERS} DESTINATION "${FMT_INC_DIR}/fmt")
   install(FILES "${pkgconfig}" DESTINATION "${FMT_PKGCONFIG_DIR}")
 endif ()
 
@@ -251,11 +327,23 @@ if (FMT_TEST)
   add_subdirectory(test)
 endif ()
 
+# Control fuzzing independent of the unit tests.
+if (FMT_FUZZ)
+  add_subdirectory(test/fuzzing)
+
+  # The FMT_FUZZ macro is used to prevent resource exhaustion in fuzzing
+  # mode and make fuzzing practically possible. It is similar to
+  # FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION but uses a different name to
+  # avoid interfering with fuzzing of projects that use {fmt}.
+  # See also https://llvm.org/docs/LibFuzzer.html#fuzzer-friendly-build-mode.
+  target_compile_definitions(fmt PUBLIC FMT_FUZZ)
+endif ()
+
 set(gitignore ${PROJECT_SOURCE_DIR}/.gitignore)
 if (MASTER_PROJECT AND EXISTS ${gitignore})
   # Get the list of ignored files from .gitignore.
   file (STRINGS ${gitignore} lines)
-  LIST(REMOVE_ITEM lines /doc/html)
+  list(REMOVE_ITEM lines /doc/html)
   foreach (line ${lines})
     string(REPLACE "." "[.]" line "${line}")
     string(REPLACE "*" ".*" line "${line}")

CONTRIBUTING.md

@@ -0,0 +1,20 @@
+Contributing to {fmt}
+=====================
+
+By submitting a pull request or a patch, you represent that you have the right
+to license your contribution to the {fmt} project owners and the community,
+agree that your contributions are licensed under the {fmt} license, and agree
+to future changes to the licensing.
+
+All C++ code must adhere to [Google C++ Style Guide](
+https://google.github.io/styleguide/cppguide.html) with the following
+exceptions:
+
+* Exceptions are permitted
+* snake_case should be used instead of UpperCamelCase for function and type
+  names
+
+All documentation must adhere to the [Google Developer Documentation Style
+Guide](https://developers.google.com/style).
+
+Thanks for contributing!

CONTRIBUTING.rst

@@ -1,12 +0,0 @@
-Contributing to fmt
-===================
-
-All C++ code must adhere to `Google C++ Style Guide
-<https://google.github.io/styleguide/cppguide.html>`_ with the following
-exceptions:
-
-* Exceptions are permitted
-* snake_case should be used instead of UpperCamelCase for function and type
-  names
-
-Thanks for contributing!

LICENSE.rst

@@ -1,23 +1,27 @@
-Copyright (c) 2012 - 2016, Victor Zverovich
+Copyright (c) 2012 - present, Victor Zverovich
 
-All rights reserved.
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
 
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are met:
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
 
-1. Redistributions of source code must retain the above copyright notice, this
-   list of conditions and the following disclaimer.
-2. Redistributions in binary form must reproduce the above copyright notice,
-   this list of conditions and the following disclaimer in the documentation
-   and/or other materials provided with the distribution.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
-ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
-DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
-ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
-(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
-LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
-ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
-SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+--- Optional exception to the license ---
+
+As an exception, if, as a result of your compiling your source code, portions
+of this Software are embedded into a machine-executable object form of such
+source code, you may redistribute such embedded portions in such object form
+without including the above copyright and permission notices.

README.rst

@@ -6,337 +6,175 @@
 
 .. image:: https://ci.appveyor.com/api/projects/status/ehjkiefde6gucy1v
    :target: https://ci.appveyor.com/project/vitaut/fmt
-   
-.. image:: https://badges.gitter.im/Join%20Chat.svg
-   :alt: Join the chat at https://gitter.im/fmtlib/fmt
-   :target: https://gitter.im/fmtlib/fmt
 
-**{fmt}** is an open-source formatting library for C++.
-It can be used as a safe and fast alternative to (s)printf and IOStreams.
+.. image:: https://oss-fuzz-build-logs.storage.googleapis.com/badges/fmt.svg
+   :alt: fmt is continuously fuzzed at oss-fuzz
+   :target: https://bugs.chromium.org/p/oss-fuzz/issues/list?\
+            colspec=ID%20Type%20Component%20Status%20Proj%20Reported%20Owner%20\
+            Summary&q=proj%3Dfmt&can=1
 
-`Documentation <http://fmtlib.net/latest/>`__
+.. image:: https://img.shields.io/badge/stackoverflow-fmt-blue.svg
+   :alt: Ask questions at StackOverflow with the tag fmt
+   :target: https://stackoverflow.com/questions/tagged/fmt
 
-This is a development branch that implements the C++ standards proposal `P0645
-Text Formatting <http://fmtlib.net/Text%20Formatting.html>`__.
-Released versions are available from the `Releases page
-<https://github.com/fmtlib/fmt/releases>`__.
+**{fmt}** is an open-source formatting library providing a fast and safe
+alternative to C stdio and C++ iostreams.
+
+If you like this project, please consider donating to BYSOL,
+an initiative to help victims of political repressions in Belarus:
+https://www.facebook.com/donate/759400044849707/108388587646909/.
+
+`Documentation <https://fmt.dev>`__
+
+Q&A: ask questions on `StackOverflow with the tag fmt
+<https://stackoverflow.com/questions/tagged/fmt>`_.
+
+Try {fmt} in `Compiler Explorer <https://godbolt.org/z/Eq5763>`_.
 
 Features
 --------
 
-* Replacement-based `format API <http://fmtlib.net/dev/api.html>`_ with
-  positional arguments for localization.
-* `Format string syntax <http://fmtlib.net/dev/syntax.html>`_ similar to the one
-  of `str.format <https://docs.python.org/2/library/stdtypes.html#str.format>`_
-  in Python.
+* Simple `format API <https://fmt.dev/latest/api.html>`_ with positional arguments
+  for localization
+* Implementation of `C++20 std::format
+  <https://en.cppreference.com/w/cpp/utility/format>`__
+* `Format string syntax <https://fmt.dev/latest/syntax.html>`_ similar to Python's
+  `format <https://docs.python.org/3/library/stdtypes.html#str.format>`_
+* Fast IEEE 754 floating-point formatter with correct rounding, shortness and
+  round-trip guarantees
 * Safe `printf implementation
-  <http://fmtlib.net/latest/api.html#printf-formatting>`_ including
-  the POSIX extension for positional arguments.
-* Support for user-defined types.
-* High speed: performance of the format API is close to that of glibc's `printf
-  <http://en.cppreference.com/w/cpp/io/c/fprintf>`_ and better than the
-  performance of IOStreams. See `Speed tests`_ and
-  `Fast integer to string conversion in C++
-  <http://zverovich.net/2013/09/07/integer-to-string-conversion-in-cplusplus.html>`_.
-* Small code size both in terms of source code (the minimum configuration
-  consists of just three header files, ``core.h``, ``format.h`` and
-  ``format-inl.h``) and compiled code. See `Compile time and code bloat`_.
-* Reliability: the library has an extensive set of `unit tests
-  <https://github.com/fmtlib/fmt/tree/master/test>`_.
+  <https://fmt.dev/latest/api.html#printf-formatting>`_ including the POSIX
+  extension for positional arguments
+* Extensibility: `support for user-defined types
+  <https://fmt.dev/latest/api.html#formatting-user-defined-types>`_
+* High performance: faster than common standard library implementations of
+  ``(s)printf``, iostreams, ``to_string`` and ``to_chars``, see `Speed tests`_
+  and `Converting a hundred million integers to strings per second
+  <http://www.zverovich.net/2020/06/13/fast-int-to-string-revisited.html>`_
+* Small code size both in terms of source code with the minimum configuration
+  consisting of just three files, ``core.h``, ``format.h`` and ``format-inl.h``,
+  and compiled code; see `Compile time and code bloat`_
+* Reliability: the library has an extensive set of `tests
+  <https://github.com/fmtlib/fmt/tree/master/test>`_ and is `continuously fuzzed
+  <https://bugs.chromium.org/p/oss-fuzz/issues/list?colspec=ID%20Type%20
+  Component%20Status%20Proj%20Reported%20Owner%20Summary&q=proj%3Dfmt&can=1>`_
 * Safety: the library is fully type safe, errors in format strings can be
   reported at compile time, automatic memory management prevents buffer overflow
-  errors.
+  errors
 * Ease of use: small self-contained code base, no external dependencies,
-  permissive BSD `license
+  permissive MIT `license
   <https://github.com/fmtlib/fmt/blob/master/LICENSE.rst>`_
-* `Portability <http://fmtlib.net/latest/index.html#portability>`_ with
-  consistent output across platforms and support for older compilers.
-* Clean warning-free codebase even on high warning levels
-  (``-Wall -Wextra -pedantic``).
-* Support for wide strings.
-* Optional header-only configuration enabled with the ``FMT_HEADER_ONLY`` macro.
+* `Portability <https://fmt.dev/latest/index.html#portability>`_ with
+  consistent output across platforms and support for older compilers
+* Clean warning-free codebase even on high warning levels such as
+  ``-Wall -Wextra -pedantic``
+* Locale-independence by default
+* Optional header-only configuration enabled with the ``FMT_HEADER_ONLY`` macro
 
-See the `documentation <http://fmtlib.net/latest/>`_ for more details.
+See the `documentation <https://fmt.dev>`_ for more details.
 
 Examples
 --------
 
-This prints ``Hello, world!`` to stdout:
+**Print to stdout** (`run <https://godbolt.org/z/Tevcjh>`_)
 
 .. code:: c++
 
-    fmt::print("Hello, {}!", "world");  // uses Python-like format string syntax
-    fmt::printf("Hello, %s!", "world"); // uses printf format string syntax
-
-Arguments can be accessed by position and arguments' indices can be repeated:
-
-.. code:: c++
-
-    std::string s = fmt::format("{0}{1}{0}", "abra", "cad");
-    // s == "abracadabra"
-
-Format strings can be checked at compile time:
-
-.. code:: c++
-
-    // test.cc
-    #define FMT_STRING_ALIAS 1
-    #include <fmt/format.h>
-    std::string s = format(fmt("{2}"), 42);
-
-.. code::
-
-    $ c++ -Iinclude -std=c++14 test.cc
-    ...
-    test.cc:4:17: note: in instantiation of function template specialization 'fmt::v5::format<S, int>' requested here
-    std::string s = format(fmt("{2}"), 42);
-                    ^
-    include/fmt/core.h:778:19: note: non-constexpr function 'on_error' cannot be used in a constant expression
-        ErrorHandler::on_error(message);
-                      ^
-    include/fmt/format.h:2226:16: note: in call to '&checker.context_->on_error(&"argument index out of range"[0])'
-          context_.on_error("argument index out of range");
-                   ^
-
-{fmt} can be used as a safe portable replacement for ``itoa``
-(`godbolt <https://godbolt.org/g/NXmpU4>`_):
-
-.. code:: c++
-
-    fmt::memory_buffer buf;
-    format_to(buf, "{}", 42);    // replaces itoa(42, buffer, 10)
-    format_to(buf, "{:x}", 42);  // replaces itoa(42, buffer, 16)
-    // access the string using to_string(buf) or buf.data()
-
-Formatting of user-defined types is supported via a simple
-`extension API <http://fmtlib.net/latest/api.html#formatting-user-defined-types>`_:
-
-.. code:: c++
-
-    #include "fmt/format.h"
-
-    struct date {
-      int year, month, day;
-    };
-
-    template <>
-    struct fmt::formatter<date> {
-      template <typename ParseContext>
-      constexpr auto parse(ParseContext &ctx) { return ctx.begin(); }
-
-      template <typename FormatContext>
-      auto format(const date &d, FormatContext &ctx) {
-        return format_to(ctx.out(), "{}-{}-{}", d.year, d.month, d.day);
-      }
-    };
-
-    std::string s = fmt::format("The date is {}", date{2012, 12, 9});
-    // s == "The date is 2012-12-9"
-
-You can create your own functions similar to `format
-<http://fmtlib.net/latest/api.html#format>`_ and
-`print <http://fmtlib.net/latest/api.html#print>`_
-which take arbitrary arguments (`godbolt <https://godbolt.org/g/MHjHVf>`_):
-
-.. code:: c++
-
-    // Prints formatted error message.
-    void vreport_error(const char *format, fmt::format_args args) {
-      fmt::print("Error: ");
-      fmt::vprint(format, args);
-    }
-    template <typename... Args>
-    void report_error(const char *format, const Args & ... args) {
-      vreport_error(format, fmt::make_format_args(args...));
+    #include <fmt/core.h>
+    
+    int main() {
+      fmt::print("Hello, world!\n");
     }
 
-    report_error("file not found: {}", path);
-
-Note that ``vreport_error`` is not parameterized on argument types which can
-improve compile times and reduce code size compared to fully parameterized
-version.
-
-Projects using this library
----------------------------
-
-* `0 A.D. <http://play0ad.com/>`_: A free, open-source, cross-platform real-time
-  strategy game
-
-* `AMPL/MP <https://github.com/ampl/mp>`_:
-  An open-source library for mathematical programming
-  
-* `AvioBook <https://www.aviobook.aero/en>`_: A comprehensive aircraft
-  operations suite
-  
-* `Celestia <https://celestia.space/>`_: Real-time 3D visualization of space
-
-* `Ceph <https://ceph.com/>`_: A scalable distributed storage system
-
-* `CUAUV <http://cuauv.org/>`_: Cornell University's autonomous underwater
-  vehicle
-
-* `HarpyWar/pvpgn <https://github.com/pvpgn/pvpgn-server>`_:
-  Player vs Player Gaming Network with tweaks
-
-* `KBEngine <http://kbengine.org/>`_: An open-source MMOG server engine
-
-* `Keypirinha <http://keypirinha.com/>`_: A semantic launcher for Windows
-
-* `Kodi <https://kodi.tv/>`_ (formerly xbmc): Home theater software
-
-* `Lifeline <https://github.com/peter-clark/lifeline>`_: A 2D game
-
-* `Drake <http://drake.mit.edu/>`_: A planning, control, and analysis toolbox
-  for nonlinear dynamical systems (MIT)
-
-* `Envoy <https://lyft.github.io/envoy/>`_: C++ L7 proxy and communication bus
-  (Lyft)
-
-* `FiveM <https://fivem.net/>`_: a modification framework for GTA V
-
-* `MongoDB Smasher <https://github.com/duckie/mongo_smasher>`_: A small tool to
-  generate randomized datasets
-
-* `OpenSpace <http://openspaceproject.com/>`_: An open-source astrovisualization
-  framework
-
-* `PenUltima Online (POL) <http://www.polserver.com/>`_:
-  An MMO server, compatible with most Ultima Online clients
-
-* `quasardb <https://www.quasardb.net/>`_: A distributed, high-performance,
-  associative database
-
-* `readpe <https://bitbucket.org/sys_dev/readpe>`_: Read Portable Executable
-
-* `redis-cerberus <https://github.com/HunanTV/redis-cerberus>`_: A Redis cluster
-  proxy
-
-* `rpclib <http://rpclib.net/>`_: A modern C++ msgpack-RPC server and client
-  library
-
-* `Saddy <https://github.com/mamontov-cpp/saddy-graphics-engine-2d>`_:
-  Small crossplatform 2D graphic engine
-
-* `Salesforce Analytics Cloud <http://www.salesforce.com/analytics-cloud/overview/>`_:
-  Business intelligence software
-
-* `Scylla <http://www.scylladb.com/>`_: A Cassandra-compatible NoSQL data store
-  that can handle 1 million transactions per second on a single server
-
-* `Seastar <http://www.seastar-project.org/>`_: An advanced, open-source C++
-  framework for high-performance server applications on modern hardware
-
-* `spdlog <https://github.com/gabime/spdlog>`_: Super fast C++ logging library
-
-* `Stellar <https://www.stellar.org/>`_: Financial platform
-
-* `Touch Surgery <https://www.touchsurgery.com/>`_: Surgery simulator
-
-* `TrinityCore <https://github.com/TrinityCore/TrinityCore>`_: Open-source
-  MMORPG framework
-
-`More... <https://github.com/search?q=cppformat&type=Code>`_
-
-If you are aware of other projects using this library, please let me know
-by `email <mailto:victor.zverovich@gmail.com>`_ or by submitting an
-`issue <https://github.com/fmtlib/fmt/issues>`_.
-
-Motivation
-----------
-
-So why yet another formatting library?
-
-There are plenty of methods for doing this task, from standard ones like
-the printf family of function and IOStreams to Boost Format library and
-FastFormat. The reason for creating a new library is that every existing
-solution that I found either had serious issues or didn't provide
-all the features I needed.
-
-Printf
-~~~~~~
-
-The good thing about printf is that it is pretty fast and readily available
-being a part of the C standard library. The main drawback is that it
-doesn't support user-defined types. Printf also has safety issues although
-they are mostly solved with `__attribute__ ((format (printf, ...))
-<http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html>`_ in GCC.
-There is a POSIX extension that adds positional arguments required for
-`i18n <https://en.wikipedia.org/wiki/Internationalization_and_localization>`_
-to printf but it is not a part of C99 and may not be available on some
-platforms.
-
-IOStreams
-~~~~~~~~~
-
-The main issue with IOStreams is best illustrated with an example:
+**Format a string** (`run <https://godbolt.org/z/oK8h33>`_)
 
 .. code:: c++
 
-    std::cout << std::setprecision(2) << std::fixed << 1.23456 << "\n";
+    std::string s = fmt::format("The answer is {}.", 42);
+    // s == "The answer is 42."
 
-which is a lot of typing compared to printf:
+**Format a string using positional arguments** (`run <https://godbolt.org/z/Yn7Txe>`_)
 
 .. code:: c++
 
-    printf("%.2f\n", 1.23456);
+    std::string s = fmt::format("I'd rather be {1} than {0}.", "right", "happy");
+    // s == "I'd rather be happy than right."
 
-Matthew Wilson, the author of FastFormat, referred to this situation with
-IOStreams as "chevron hell". IOStreams doesn't support positional arguments
-by design.
+**Print chrono durations** (`run <https://godbolt.org/z/K8s4Mc>`_)
 
-The good part is that IOStreams supports user-defined types and is safe
-although error reporting is awkward.
+.. code:: c++
 
-Boost Format library
-~~~~~~~~~~~~~~~~~~~~
+    #include <fmt/chrono.h>
 
-This is a very powerful library which supports both printf-like format
-strings and positional arguments. Its main drawback is performance.
-According to various benchmarks it is much slower than other methods
-considered here. Boost Format also has excessive build times and severe
-code bloat issues (see `Benchmarks`_).
+    int main() {
+      using namespace std::literals::chrono_literals;
+      fmt::print("Default format: {} {}\n", 42s, 100ms);
+      fmt::print("strftime-like format: {:%H:%M:%S}\n", 3h + 15min + 30s);
+    }
 
-FastFormat
-~~~~~~~~~~
+Output::
 
-This is an interesting library which is fast, safe and has positional
-arguments. However it has significant limitations, citing its author:
+    Default format: 42s 100ms
+    strftime-like format: 03:15:30
 
-    Three features that have no hope of being accommodated within the
-    current design are:
+**Print a container** (`run <https://godbolt.org/z/MjsY7c>`_)
 
-    * Leading zeros (or any other non-space padding)
-    * Octal/hexadecimal encoding
-    * Runtime width/alignment specification
+.. code:: c++
 
-It is also quite big and has a heavy dependency, STLSoft, which might be
-too restrictive for using it in some projects.
+    #include <vector>
+    #include <fmt/ranges.h>
 
-Loki SafeFormat
-~~~~~~~~~~~~~~~
+    int main() {
+      std::vector<int> v = {1, 2, 3};
+      fmt::print("{}\n", v);
+    }
 
-SafeFormat is a formatting library which uses printf-like format strings
-and is type safe. It doesn't support user-defined types or positional
-arguments. It makes unconventional use of ``operator()`` for passing
-format arguments.
+Output::
 
-Tinyformat
-~~~~~~~~~~
+    {1, 2, 3}
 
-This library supports printf-like format strings and is very small and
-fast. Unfortunately it doesn't support positional arguments and wrapping
-it in C++98 is somewhat difficult. Also its performance and code compactness
-are limited by IOStreams.
+**Check a format string at compile time**
 
-Boost Spirit.Karma
-~~~~~~~~~~~~~~~~~~
+.. code:: c++
 
-This is not really a formatting library but I decided to include it here
-for completeness. As IOStreams it suffers from the problem of mixing
-verbatim text with arguments. The library is pretty fast, but slower
-on integer formatting than ``fmt::Writer`` on Karma's own benchmark,
-see `Fast integer to string conversion in C++
-<http://zverovich.net/2013/09/07/integer-to-string-conversion-in-cplusplus.html>`_.
+    std::string s = fmt::format(FMT_STRING("{:d}"), "don't panic");
+
+This gives a compile-time error because ``d`` is an invalid format specifier for
+a string.
+
+**Write a file from a single thread**
+
+.. code:: c++
+
+    #include <fmt/os.h>
+
+    int main() {
+      auto out = fmt::output_file("guide.txt");
+      out.print("Don't {}", "Panic");
+    }
+
+This can be `5 to 9 times faster than fprintf
+<http://www.zverovich.net/2020/08/04/optimal-file-buffer-size.html>`_.
+
+**Print with colors and text styles**
+
+.. code:: c++
+
+    #include <fmt/color.h>
+
+    int main() {
+      fmt::print(fg(fmt::color::crimson) | fmt::emphasis::bold,
+                 "Hello, {}!\n", "world");
+      fmt::print(fg(fmt::color::floral_white) | bg(fmt::color::slate_gray) |
+                 fmt::emphasis::underline, "Hello, {}!\n", "мир");
+      fmt::print(fg(fmt::color::steel_blue) | fmt::emphasis::italic,
+                 "Hello, {}!\n", "世界");
+    }
+
+Output on a modern terminal:
+
+.. image:: https://user-images.githubusercontent.com/
+           576385/88485597-d312f600-cf2b-11ea-9cbe-61f535a86e28.png
 
 Benchmarks
 ----------
@@ -344,32 +182,33 @@ Benchmarks
 Speed tests
 ~~~~~~~~~~~
 
-The following speed tests results were generated by building
-``tinyformat_test.cpp`` on Ubuntu GNU/Linux 14.04.1 with
-``g++-4.8.2 -O3 -DSPEED_TEST -DHAVE_FORMAT``, and taking the best of three
-runs.  In the test, the format string ``"%0.10f:%04d:%+g:%s:%p:%c:%%\n"`` or
-equivalent is filled 2000000 times with output sent to ``/dev/null``; for
-further details see the `source
-<https://github.com/fmtlib/format-benchmark/blob/master/tinyformat_test.cpp>`_.
-
 ================= ============= ===========
 Library           Method        Run Time, s
 ================= ============= ===========
-libc              printf          1.35
-libc++            std::ostream    3.42
-fmt 534bff7       fmt::print      1.56
-tinyformat 2.0.1  tfm::printf     3.73
-Boost Format 1.54 boost::format   8.44
-Folly Format      folly::format   2.54
+libc              printf          1.04
+libc++            std::ostream    3.05
+{fmt} 6.1.1       fmt::print      0.75
+Boost Format 1.67 boost::format   7.24
+Folly Format      folly::format   2.23
 ================= ============= ===========
 
-As you can see ``boost::format`` is much slower than the alternative methods; this
-is confirmed by `other tests <http://accu.org/index.php/journals/1539>`_.
-Tinyformat is quite good coming close to IOStreams.  Unfortunately tinyformat
-cannot be faster than the IOStreams because it uses them internally.
-Performance of fmt is close to that of printf, being `faster than printf on integer
-formatting <http://zverovich.net/2013/09/07/integer-to-string-conversion-in-cplusplus.html>`_,
-but slower on floating-point formatting which dominates this benchmark.
+{fmt} is the fastest of the benchmarked methods, ~35% faster than ``printf``.
+
+The above results were generated by building ``tinyformat_test.cpp`` on macOS
+10.14.6 with ``clang++ -O3 -DNDEBUG -DSPEED_TEST -DHAVE_FORMAT``, and taking the
+best of three runs. In the test, the format string ``"%0.10f:%04d:%+g:%s:%p:%c:%%\n"``
+or equivalent is filled 2,000,000 times with output sent to ``/dev/null``; for
+further details refer to the `source
+<https://github.com/fmtlib/format-benchmark/blob/master/tinyformat_test.cpp>`_.
+
+{fmt} is up to 20-30x faster than ``std::ostringstream`` and ``sprintf`` on
+floating-point formatting (`dtoa-benchmark <https://github.com/fmtlib/dtoa-benchmark>`_)
+and faster than `double-conversion <https://github.com/google/double-conversion>`_ and
+`ryu <https://github.com/ulfjack/ryu>`_:
+
+.. image:: https://user-images.githubusercontent.com/576385/
+           95684665-11719600-0ba8-11eb-8e5b-972ff4e49428.png
+   :target: https://fmt.dev/unknown_mac64_clang12.0.html
 
 Compile time and code bloat
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -390,15 +229,14 @@ Method        Compile Time, s Executable size, KiB Stripped size, KiB
 ============= =============== ==================== ==================
 printf                    2.6                   29                 26
 printf+string            16.4                   29                 26
-IOStreams                31.1                   59                 55
-fmt                      19.0                   37                 34
-tinyformat               44.0                  103                 97
+iostreams                31.1                   59                 55
+{fmt}                    19.0                   37                 34
 Boost Format             91.9                  226                203
 Folly Format            115.7                  101                 88
 ============= =============== ==================== ==================
 
-As you can see, fmt has 60% less overhead in terms of resulting binary code
-size compared to IOStreams and comes pretty close to ``printf``. Boost Format
+As you can see, {fmt} has 60% less overhead in terms of resulting binary code
+size compared to iostreams and comes pretty close to ``printf``. Boost Format
 and Folly Format have the largest overheads.
 
 ``printf+string`` is the same as ``printf`` but with extra ``<string>``
@@ -411,17 +249,15 @@ Method        Compile Time, s Executable size, KiB Stripped size, KiB
 ============= =============== ==================== ==================
 printf                    2.2                   33                 30
 printf+string            16.0                   33                 30
-IOStreams                28.3                   56                 52
-fmt                      18.2                   59                 50
-tinyformat               32.6                   88                 82
+iostreams                28.3                   56                 52
+{fmt}                    18.2                   59                 50
 Boost Format             54.1                  365                303
 Folly Format             79.9                  445                430
 ============= =============== ==================== ==================
 
-``libc``, ``lib(std)c++`` and ``libfmt`` are all linked as shared
-libraries to compare formatting function overhead only. Boost Format
-and tinyformat are header-only libraries so they don't provide any
-linkage options.
+``libc``, ``lib(std)c++`` and ``libfmt`` are all linked as shared libraries to
+compare formatting function overhead only. Boost Format is a
+header-only library so it doesn't provide any linkage options.
 
 Running the tests
 ~~~~~~~~~~~~~~~~~
@@ -429,7 +265,7 @@ Running the tests
 Please refer to `Building the library`__ for the instructions on how to build
 the library and run the unit tests.
 
-__ http://fmtlib.net/latest/usage.html#building-the-library
+__ https://fmt.dev/latest/usage.html#building-the-library
 
 Benchmarks reside in a separate repository,
 `format-benchmarks <https://github.com/fmtlib/format-benchmark>`_,
@@ -448,72 +284,223 @@ or the bloat test::
 
     $ make bloat-test
 
-FAQ
----
+Projects using this library
+---------------------------
 
-Q: how can I capture formatting arguments and format them later?
+* `0 A.D. <https://play0ad.com/>`_: a free, open-source, cross-platform
+  real-time strategy game
 
-A: use ``std::tuple``:
+* `AMPL/MP <https://github.com/ampl/mp>`_:
+  an open-source library for mathematical programming
+
+* `Aseprite <https://github.com/aseprite/aseprite>`_:
+  animated sprite editor & pixel art tool 
+
+* `AvioBook <https://www.aviobook.aero/en>`_: a comprehensive aircraft
+  operations suite
+  
+* `Blizzard Battle.net <https://battle.net/>`_: an online gaming platform
+  
+* `Celestia <https://celestia.space/>`_: real-time 3D visualization of space
+
+* `Ceph <https://ceph.com/>`_: a scalable distributed storage system
+
+* `ccache <https://ccache.dev/>`_: a compiler cache
+
+* `ClickHouse <https://github.com/ClickHouse/ClickHouse>`_: analytical database
+  management system
+
+* `CUAUV <http://cuauv.org/>`_: Cornell University's autonomous underwater
+  vehicle
+
+* `Drake <https://drake.mit.edu/>`_: a planning, control, and analysis toolbox
+  for nonlinear dynamical systems (MIT)
+
+* `Envoy <https://lyft.github.io/envoy/>`_: C++ L7 proxy and communication bus
+  (Lyft)
+
+* `FiveM <https://fivem.net/>`_: a modification framework for GTA V
+
+* `Folly <https://github.com/facebook/folly>`_: Facebook open-source library
+
+* `HarpyWar/pvpgn <https://github.com/pvpgn/pvpgn-server>`_:
+  Player vs Player Gaming Network with tweaks
+
+* `KBEngine <https://github.com/kbengine/kbengine>`_: an open-source MMOG server
+  engine
+
+* `Keypirinha <https://keypirinha.com/>`_: a semantic launcher for Windows
+
+* `Kodi <https://kodi.tv/>`_ (formerly xbmc): home theater software
+
+* `Knuth <https://kth.cash/>`_: high-performance Bitcoin full-node
+
+* `Microsoft Verona <https://github.com/microsoft/verona>`_:
+  research programming language for concurrent ownership
+
+* `MongoDB <https://mongodb.com/>`_: distributed document database
+
+* `MongoDB Smasher <https://github.com/duckie/mongo_smasher>`_: a small tool to
+  generate randomized datasets
+
+* `OpenSpace <https://openspaceproject.com/>`_: an open-source
+  astrovisualization framework
+
+* `PenUltima Online (POL) <https://www.polserver.com/>`_:
+  an MMO server, compatible with most Ultima Online clients
+
+* `PyTorch <https://github.com/pytorch/pytorch>`_: an open-source machine
+  learning library
+
+* `quasardb <https://www.quasardb.net/>`_: a distributed, high-performance,
+  associative database
+  
+* `Quill <https://github.com/odygrd/quill>`_: asynchronous low-latency logging library
+
+* `QKW <https://github.com/ravijanjam/qkw>`_: generalizing aliasing to simplify
+  navigation, and executing complex multi-line terminal command sequences
+
+* `redis-cerberus <https://github.com/HunanTV/redis-cerberus>`_: a Redis cluster
+  proxy
+
+* `redpanda <https://vectorized.io/redpanda>`_: a 10x faster Kafka® replacement
+  for mission critical systems written in C++
+
+* `rpclib <http://rpclib.net/>`_: a modern C++ msgpack-RPC server and client
+  library
+
+* `Salesforce Analytics Cloud
+  <https://www.salesforce.com/analytics-cloud/overview/>`_:
+  business intelligence software
+
+* `Scylla <https://www.scylladb.com/>`_: a Cassandra-compatible NoSQL data store
+  that can handle 1 million transactions per second on a single server
+
+* `Seastar <http://www.seastar-project.org/>`_: an advanced, open-source C++
+  framework for high-performance server applications on modern hardware
+
+* `spdlog <https://github.com/gabime/spdlog>`_: super fast C++ logging library
+
+* `Stellar <https://www.stellar.org/>`_: financial platform
+
+* `Touch Surgery <https://www.touchsurgery.com/>`_: surgery simulator
+
+* `TrinityCore <https://github.com/TrinityCore/TrinityCore>`_: open-source
+  MMORPG framework
+
+* `Windows Terminal <https://github.com/microsoft/terminal>`_: the new Windows
+  terminal
+
+`More... <https://github.com/search?q=fmtlib&type=Code>`_
+
+If you are aware of other projects using this library, please let me know
+by `email <mailto:victor.zverovich@gmail.com>`_ or by submitting an
+`issue <https://github.com/fmtlib/fmt/issues>`_.
+
+Motivation
+----------
+
+So why yet another formatting library?
+
+There are plenty of methods for doing this task, from standard ones like
+the printf family of function and iostreams to Boost Format and FastFormat
+libraries. The reason for creating a new library is that every existing
+solution that I found either had serious issues or didn't provide
+all the features I needed.
+
+printf
+~~~~~~
+
+The good thing about ``printf`` is that it is pretty fast and readily available
+being a part of the C standard library. The main drawback is that it
+doesn't support user-defined types. ``printf`` also has safety issues although
+they are somewhat mitigated with `__attribute__ ((format (printf, ...))
+<https://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html>`_ in GCC.
+There is a POSIX extension that adds positional arguments required for
+`i18n <https://en.wikipedia.org/wiki/Internationalization_and_localization>`_
+to ``printf`` but it is not a part of C99 and may not be available on some
+platforms.
+
+iostreams
+~~~~~~~~~
+
+The main issue with iostreams is best illustrated with an example:
 
 .. code:: c++
 
-   template <typename... Args>
-   auto capture(const Args&... args) {
-     return std::make_tuple(args...);
-   }
+    std::cout << std::setprecision(2) << std::fixed << 1.23456 << "\n";
 
-   auto print_message = [](const auto&... args) {
-     fmt::print(args...);
-   };
+which is a lot of typing compared to printf:
 
-   // Capture and store arguments:
-   auto args = capture("{} {}", 42, "foo");
-   // Do formatting:
-   std::apply(print_message, args);
+.. code:: c++
+
+    printf("%.2f\n", 1.23456);
+
+Matthew Wilson, the author of FastFormat, called this "chevron hell". iostreams
+don't support positional arguments by design.
+
+The good part is that iostreams support user-defined types and are safe although
+error handling is awkward.
+
+Boost Format
+~~~~~~~~~~~~
+
+This is a very powerful library which supports both ``printf``-like format
+strings and positional arguments. Its main drawback is performance. According to
+various, benchmarks it is much slower than other methods considered here. Boost
+Format also has excessive build times and severe code bloat issues (see
+`Benchmarks`_).
+
+FastFormat
+~~~~~~~~~~
+
+This is an interesting library which is fast, safe and has positional arguments.
+However, it has significant limitations, citing its author:
+
+    Three features that have no hope of being accommodated within the
+    current design are:
+
+    * Leading zeros (or any other non-space padding)
+    * Octal/hexadecimal encoding
+    * Runtime width/alignment specification
+
+It is also quite big and has a heavy dependency, STLSoft, which might be too
+restrictive for using it in some projects.
+
+Boost Spirit.Karma
+~~~~~~~~~~~~~~~~~~
+
+This is not really a formatting library but I decided to include it here for
+completeness. As iostreams, it suffers from the problem of mixing verbatim text
+with arguments. The library is pretty fast, but slower on integer formatting
+than ``fmt::format_to`` with format string compilation on Karma's own benchmark,
+see `Converting a hundred million integers to strings per second
+<http://www.zverovich.net/2020/06/13/fast-int-to-string-revisited.html>`_.
 
 License
 -------
 
-fmt is distributed under the BSD `license
+{fmt} is distributed under the MIT `license
 <https://github.com/fmtlib/fmt/blob/master/LICENSE.rst>`_.
 
-The `Format String Syntax
-<http://fmtlib.net/latest/syntax.html>`_
+Documentation License
+---------------------
+
+The `Format String Syntax <https://fmt.dev/latest/syntax.html>`_
 section in the documentation is based on the one from Python `string module
-documentation <https://docs.python.org/3/library/string.html#module-string>`_
-adapted for the current library. For this reason the documentation is
-distributed under the Python Software Foundation license available in
-`doc/python-license.txt
+documentation <https://docs.python.org/3/library/string.html#module-string>`_.
+For this reason the documentation is distributed under the Python Software
+Foundation license available in `doc/python-license.txt
 <https://raw.github.com/fmtlib/fmt/master/doc/python-license.txt>`_.
-It only applies if you distribute the documentation of fmt.
+It only applies if you distribute the documentation of {fmt}.
 
-Acknowledgments
----------------
+Maintainers
+-----------
 
-The fmt library is maintained by Victor Zverovich (`vitaut
+The {fmt} library is maintained by Victor Zverovich (`vitaut
 <https://github.com/vitaut>`_) and Jonathan Müller (`foonathan
 <https://github.com/foonathan>`_) with contributions from many other people.
 See `Contributors <https://github.com/fmtlib/fmt/graphs/contributors>`_ and
 `Releases <https://github.com/fmtlib/fmt/releases>`_ for some of the names.
 Let us know if your contribution is not listed or mentioned incorrectly and
 we'll make it right.
-
-The benchmark section of this readme file and the performance tests are taken
-from the excellent `tinyformat <https://github.com/c42f/tinyformat>`_ library
-written by Chris Foster.  Boost Format library is acknowledged transitively
-since it had some influence on tinyformat.
-Some ideas used in the implementation are borrowed from `Loki
-<http://loki-lib.sourceforge.net/>`_ SafeFormat and `Diagnostic API
-<http://clang.llvm.org/doxygen/classclang_1_1Diagnostic.html>`_ in
-`Clang <http://clang.llvm.org/>`_.
-Format string syntax and the documentation are based on Python's `str.format
-<http://docs.python.org/2/library/stdtypes.html#str.format>`_.
-Thanks `Doug Turnbull <https://github.com/softwaredoug>`_ for his valuable
-comments and contribution to the design of the type-safe API and
-`Gregory Czajkowski <https://github.com/gcflymoto>`_ for implementing binary
-formatting. Thanks `Ruslan Baratov <https://github.com/ruslo>`_ for comprehensive
-`comparison of integer formatting algorithms <https://github.com/ruslo/int-dec-format-tests>`_
-and useful comments regarding performance, `Boris Kaul <https://github.com/localvoid>`_ for
-`C++ counting digits benchmark <https://github.com/localvoid/cxx-benchmark-count-digits>`_.
-Thanks to `CarterLi <https://github.com/CarterLi>`_ for contributing various
-improvements to the code.

doc/CMakeLists.txt

@@ -4,9 +4,14 @@ if (NOT DOXYGEN)
   return ()
 endif ()
 
-add_custom_target(doc
-  COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/build.py ${FMT_VERSION}
-  SOURCES api.rst syntax.rst build.py conf.py _templates/layout.html)
+find_package(PythonInterp QUIET REQUIRED)
 
+add_custom_target(doc
+  COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/build.py
+                               ${FMT_VERSION}
+  SOURCES api.rst syntax.rst usage.rst build.py conf.py _templates/layout.html)
+
+include(GNUInstallDirs)
 install(DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/html/
-        DESTINATION share/doc/fmt OPTIONAL)
+        DESTINATION ${CMAKE_INSTALL_DATAROOTDIR}/doc/fmt OPTIONAL
+        PATTERN ".doctrees" EXCLUDE)

doc/_templates/layout.html

@@ -6,14 +6,13 @@
 <meta name="author" content="Victor Zverovich">
 <link rel="stylesheet" href="_static/fmt.css">
 {# Google Analytics #}
+<script async src="https://www.googletagmanager.com/gtag/js?id=UA-20116650-4"></script>
 <script>
-  (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
-    (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();
-    a=s.createElement(o),m=s.getElementsByTagName(o)[0];a.async=1;
-    a.src=g;m.parentNode.insertBefore(a,m)
-  })(window,document,'script','//www.google-analytics.com/analytics.js','ga');
-  ga('create', 'UA-20116650-4', 'fmtlib.net');
-  ga('send', 'pageview');
+  window.dataLayer = window.dataLayer || [];
+  function gtag(){dataLayer.push(arguments);}
+  gtag('js', new Date());
+
+  gtag('config', 'UA-20116650-4');
 </script>
 {% endblock %}
 
@@ -58,7 +57,7 @@
                 <span class="caret"></span></a>
               <ul class="dropdown-menu" role="menu">
                 {% for v in versions.split(',') %}
-                <li><a href="http://fmtlib.net/{{v}}">{{v}}</a></li>
+                <li><a href="https://fmt.dev/{{v}}">{{v}}</a></li>
                 {% endfor %}
               </ul>
             </li>
@@ -84,7 +83,7 @@
 <div class="jumbotron">
   <div class="tb-container">
     <h1>{fmt}</h1>
-    <p class="lead">Small, safe and fast formatting library</p>
+    <p class="lead">A modern formatting library</p>
     <div class="btn-group" role="group">
       {% set name = 'fmt' if version.split('.')[0]|int >= 3 else 'cppformat' %}
       <a class="btn btn-success"

doc/api.rst

@@ -9,13 +9,18 @@ The {fmt} library API consists of the following parts:
 * :ref:`fmt/core.h <core-api>`: the core API providing argument handling
   facilities and a lightweight subset of formatting functions
 * :ref:`fmt/format.h <format-api>`: the full format API providing compile-time
-  format string checks, output iterator and user-defined type support
-* :ref:`fmt/time.h <time-api>`: date and time formatting
+  format string checks, wide string, output iterator and user-defined type
+  support
+* :ref:`fmt/ranges.h <ranges-api>`: additional formatting support for ranges
+  and tuples
+* :ref:`fmt/chrono.h <chrono-api>`: date and time formatting
+* :ref:`fmt/compile.h <compile-api>`: format string compilation
+* :ref:`fmt/color.h <color-api>`: terminal color and text style
 * :ref:`fmt/ostream.h <ostream-api>`: ``std::ostream`` support
 * :ref:`fmt/printf.h <printf-api>`: ``printf`` formatting
 
 All functions and types provided by the library reside in namespace ``fmt`` and
-macros have prefix ``FMT_`` or ``fmt``.
+macros have prefix ``FMT_``.
 
 .. _core-api:
 
@@ -23,7 +28,8 @@ Core API
 ========
 
 ``fmt/core.h`` defines the core API which provides argument handling facilities
-and a lightweight subset of formatting functions.
+and a lightweight subset of formatting functions. In the header-only mode
+include ``fmt/format.h`` instead of ``fmt/core.h``.
 
 The following functions use :ref:`format string syntax <syntax>`
 similar to that of Python's `str.format
@@ -39,31 +45,68 @@ participate in an overload resolution if the latter is not a string.
 
 .. _format:
 
-.. doxygenfunction:: format(const S&, const Args&...)
-.. doxygenfunction:: vformat(const S&, basic_format_args<typename buffer_context<Char>::type>)
+.. doxygenfunction:: format(const S&, Args&&...)
+.. doxygenfunction:: vformat(const S&, basic_format_args<buffer_context<type_identity_t<Char>>>)
+
+.. doxygenfunction:: fmt::format_to(OutputIt, const S&, Args&&...)
+.. doxygenfunction:: fmt::format_to_n(OutputIt, size_t, const S&, const Args&...)
+.. doxygenfunction:: fmt::formatted_size(string_view, Args&&...)
 
 .. _print:
 
-.. doxygenfunction:: print(const S&, const Args&...)
+.. doxygenfunction:: print(const S&, Args&&...)
 .. doxygenfunction:: vprint(string_view, format_args)
 
-.. doxygenfunction:: print(std::FILE *, const S&, const Args&...)
+.. doxygenfunction:: print(std::FILE *, const S&, Args&&...)
 .. doxygenfunction:: vprint(std::FILE *, string_view, format_args)
-.. doxygenfunction:: vprint(std::FILE *, wstring_view, wformat_args)
 
-Named arguments
+Named Arguments
 ---------------
 
-.. doxygenfunction:: fmt::arg(string_view, const T&)
+.. doxygenfunction:: fmt::arg(const S&, const T&)
 
-Argument lists
+Named arguments are not supported in compile-time checks at the moment.
+
+Argument Lists
 --------------
 
+You can create your own formatting function with compile-time checks and small
+binary footprint, for example (https://godbolt.org/z/oba4Mc):
+
+.. code:: c++
+
+    #include <fmt/format.h>
+
+    void vlog(const char* file, int line, fmt::string_view format,
+              fmt::format_args args) {
+      fmt::print("{}: {}: ", file, line);
+      fmt::vprint(format, args);
+    }
+
+    template <typename S, typename... Args>
+    void log(const char* file, int line, const S& format, Args&&... args) {
+      vlog(file, line, format,
+          fmt::make_args_checked<Args...>(format, args...));
+    }
+
+    #define MY_LOG(format, ...) \
+      log(__FILE__, __LINE__, FMT_STRING(format), __VA_ARGS__)
+
+    MY_LOG("invalid squishiness: {}", 42);
+
+Note that ``vlog`` is not parameterized on argument types which improves compile
+times and reduces binary code size compared to a fully parameterized version.
+
+.. doxygenfunction:: fmt::make_args_checked(const S&, const remove_reference_t<Args>&...)
+
 .. doxygenfunction:: fmt::make_format_args(const Args&...)
 
 .. doxygenclass:: fmt::format_arg_store
    :members:
 
+.. doxygenclass:: fmt::dynamic_format_arg_store
+   :members:
+
 .. doxygenclass:: fmt::basic_format_args
    :members:
 
@@ -81,20 +124,39 @@ Compatibility
 .. doxygentypedef:: fmt::string_view
 .. doxygentypedef:: fmt::wstring_view
 
+Locale
+------
+
+All formatting is locale-independent by default. Use the ``'L'`` format
+specifier to insert the appropriate number separator characters from the
+locale::
+
+  #include <fmt/core.h>
+  #include <locale>
+
+  std::locale::global(std::locale("en_US.UTF-8"));
+  auto s = fmt::format("{:L}", 1000000);  // s == "1,000,000"
+
 .. _format-api:
 
 Format API
 ==========
 
 ``fmt/format.h`` defines the full format API providing compile-time format
-string checks, output iterator and user-defined type support.
+string checks, wide string, output iterator and user-defined type support.
 
-Compile-time format string checks
+Compile-time Format String Checks
 ---------------------------------
 
-.. doxygendefine:: fmt
+Compile-time checks are enabled when using ``FMT_STRING``. They support built-in
+and string types as well as user-defined types with ``constexpr`` ``parse``
+functions in their ``formatter`` specializations.
 
-Formatting user-defined types
+.. doxygendefine:: FMT_STRING
+
+.. _udt:
+
+Formatting User-defined Types
 -----------------------------
 
 To make a user-defined type formattable, specialize the ``formatter<T>`` struct
@@ -104,40 +166,65 @@ template and implement ``parse`` and ``format`` methods::
 
   struct point { double x, y; };
 
-  namespace fmt {
   template <>
-  struct formatter<point> {
-    template <typename ParseContext>
-    constexpr auto parse(ParseContext &ctx) { return ctx.begin(); }
+  struct fmt::formatter<point> {
+    // Presentation format: 'f' - fixed, 'e' - exponential.
+    char presentation = 'f';
 
+    // Parses format specifications of the form ['f' | 'e'].
+    constexpr auto parse(format_parse_context& ctx) {
+    // auto parse(format_parse_context &ctx) -> decltype(ctx.begin()) // c++11
+      // [ctx.begin(), ctx.end()) is a character range that contains a part of
+      // the format string starting from the format specifications to be parsed,
+      // e.g. in
+      //
+      //   fmt::format("{:f} - point of interest", point{1, 2});
+      //
+      // the range will contain "f} - point of interest". The formatter should
+      // parse specifiers until '}' or the end of the range. In this example
+      // the formatter should parse the 'f' specifier and return an iterator
+      // pointing to '}'.
+
+      // Parse the presentation format and store it in the formatter:
+      auto it = ctx.begin(), end = ctx.end();
+      if (it != end && (*it == 'f' || *it == 'e')) presentation = *it++;
+
+      // Check if reached the end of the range:
+      if (it != end && *it != '}')
+        throw format_error("invalid format");
+
+      // Return an iterator past the end of the parsed range:
+      return it;
+    }
+
+    // Formats the point p using the parsed format specification (presentation)
+    // stored in this formatter.
     template <typename FormatContext>
-    auto format(const point &p, FormatContext &ctx) {
-      return format_to(ctx.begin(), "({:.1f}, {:.1f})", p.x, p.y);
+    auto format(const point& p, FormatContext& ctx) {
+    // auto format(const point &p, FormatContext &ctx) -> decltype(ctx.out()) // c++11
+      // ctx.out() is an output iterator to write to.
+      return format_to(
+          ctx.out(),
+          presentation == 'f' ? "({:.1f}, {:.1f})" : "({:.1e}, {:.1e})",
+          p.x, p.y);
     }
   };
-  }
 
 Then you can pass objects of type ``point`` to any formatting function::
 
   point p = {1, 2};
-  std::string s = fmt::format("{}", p);
+  std::string s = fmt::format("{:f}", p);
   // s == "(1.0, 2.0)"
 
-In the example above the ``formatter<point>::parse`` function ignores the
-contents of the format string referred to by ``ctx.begin()`` so the object will
-always be formatted in the same way. See ``formatter<tm>::parse`` in
-:file:`fmt/time.h` for an advanced example of how to parse the format string and
-customize the formatted output.
-
-You can also reuse existing formatters, for example::
+You can also reuse existing formatters via inheritance or composition, for
+example::
 
   enum class color {red, green, blue};
 
-  template <>
-  struct fmt::formatter<color>: formatter<string_view> {
+  template <> struct fmt::formatter<color>: formatter<string_view> {
     // parse is inherited from formatter<string_view>.
     template <typename FormatContext>
-    auto format(color c, FormatContext &ctx) {
+    auto format(color c, FormatContext& ctx) {
       string_view name = "unknown";
       switch (c) {
       case color::red:   name = "red"; break;
@@ -148,6 +235,15 @@ You can also reuse existing formatters, for example::
     }
   };
 
+Since ``parse`` is inherited from ``formatter<string_view>`` it will recognize
+all string format specifications, for example
+
+.. code-block:: c++
+
+   fmt::format("{:>10}", color::blue)
+
+will return ``"      blue"``.
+
 You can also write a formatter for a hierarchy of classes::
 
   #include <type_traits>
@@ -177,15 +273,18 @@ You can also write a formatter for a hierarchy of classes::
     fmt::print("{}", a); // prints "B"
   }
 
-This section shows how to define a custom format function for a user-defined
-type. The next section describes how to get ``fmt`` to use a conventional stream
-output ``operator<<`` when one is defined for a user-defined type.
+If a type provides both a ``formatter`` specialization and an implicit
+conversion to a formattable type, the specialization takes precedence over the
+conversion.
 
-Output iterator support
+.. doxygenclass:: fmt::basic_format_parse_context
+   :members:
+
+Output Iterator Support
 -----------------------
 
-.. doxygenfunction:: fmt::format_to(OutputIt, const S&, const Args&...)
-.. doxygenfunction:: fmt::format_to_n(OutputIt, std::size_t, string_view, const Args&...)
+.. doxygenfunction:: fmt::format_to(OutputIt, const S&, Args&&...)
+.. doxygenfunction:: fmt::format_to_n(OutputIt, size_t, const S&, const Args&...)
 .. doxygenstruct:: fmt::format_to_n_result
    :members:
 
@@ -194,28 +293,39 @@ Literal-based API
 
 The following user-defined literals are defined in ``fmt/format.h``.
 
-.. doxygenfunction:: operator""_format(const char *, std::size_t)
+.. doxygenfunction:: operator""_format(const char *, size_t)
 
-.. doxygenfunction:: operator""_a(const char *, std::size_t)
+.. doxygenfunction:: operator""_a(const char *, size_t)
 
 Utilities
 ---------
 
+.. doxygenstruct:: fmt::is_char
+
 .. doxygentypedef:: fmt::char_t
 
-.. doxygenfunction:: fmt::formatted_size(string_view, const Args&...)
+.. doxygenfunction:: fmt::ptr(const T *)
+.. doxygenfunction:: fmt::ptr(const std::unique_ptr<T>&)
+.. doxygenfunction:: fmt::ptr(const std::shared_ptr<T>&)
 
 .. doxygenfunction:: fmt::to_string(const T&)
 
 .. doxygenfunction:: fmt::to_wstring(const T&)
 
-.. doxygenfunction:: fmt::to_string_view(basic_string_view<Char>)
+.. doxygenfunction:: fmt::to_string_view(const Char *)
+
+.. doxygenfunction:: fmt::join(Range&&, string_view)
+
+.. doxygenfunction:: fmt::join(It, Sentinel, string_view)
+
+.. doxygenclass:: fmt::detail::buffer
+   :members:
 
 .. doxygenclass:: fmt::basic_memory_buffer
    :protected-members:
    :members:
 
-System errors
+System Errors
 -------------
 
 fmt does not use ``errno`` to communicate errors to the user, but it may call
@@ -230,9 +340,7 @@ the value of ``errno`` being preserved by library functions.
 .. doxygenclass:: fmt::windows_error
    :members:
 
-.. _formatstrings:
-
-Custom allocators
+Custom Allocators
 -----------------
 
 The {fmt} library supports custom dynamic memory allocators.
@@ -258,80 +366,86 @@ allocator::
     template <typename ...Args>
     inline custom_string format(custom_allocator alloc,
                                 fmt::string_view format_str,
-                                const Args & ... args) {
+                                const Args& ... args) {
       return vformat(alloc, format_str, fmt::make_format_args(args...));
     }
 
-The allocator will be used for the output container only. If you are using named
-arguments, the container that stores pointers to them will be allocated using
-the default allocator. Also floating-point formatting falls back on ``sprintf``
-which may do allocations.
+The allocator will be used for the output container only. Formatting functions
+normally don't do any allocations for built-in and string types except for
+non-default floating-point formatting that occasionally falls back on
+``sprintf``.
 
-Custom formatting of built-in types
------------------------------------
+.. _ranges-api:
 
-It is possible to change the way arguments are formatted by providing a
-custom argument formatter class::
+Ranges and Tuple Formatting
+===========================
 
-  using arg_formatter =
-    fmt::arg_formatter<fmt::back_insert_range<fmt::internal::buffer>>;
+The library also supports convenient formatting of ranges and tuples::
 
-  // A custom argument formatter that formats negative integers as unsigned
-  // with the ``x`` format specifier.
-  class custom_arg_formatter : public arg_formatter {
-   public:
-    custom_arg_formatter(fmt::format_context &ctx,
-                         fmt::format_specs *spec = nullptr)
-      : arg_formatter(ctx, spec) {}
+  #include <fmt/ranges.h>
 
-    using arg_formatter::operator();
+  std::tuple<char, int, float> t{'a', 1, 2.0f};
+  // Prints "('a', 1, 2.0)"
+  fmt::print("{}", t);
 
-    auto operator()(int value) {
-      if (spec().type() == 'x')
-        return (*this)(static_cast<unsigned>(value)); // convert to unsigned and format
-      return arg_formatter::operator()(value);
-    }
-  };
 
-  std::string custom_vformat(fmt::string_view format_str, fmt::format_args args) {
-    fmt::memory_buffer buffer;
-    // Pass custom argument formatter as a template arg to vformat_to.
-    fmt::vformat_to<custom_arg_formatter>(buffer, format_str, args);
-    return fmt::to_string(buffer);
-  }
+NOTE: currently, the overload of ``fmt::join`` for iterables exists in the main
+``format.h`` header, but expect this to change in the future.
 
-  template <typename ...Args>
-  inline std::string custom_format(
-      fmt::string_view format_str, const Args &... args) {
-    return custom_vformat(format_str, fmt::make_format_args(args...));
-  }
+Using ``fmt::join``, you can separate tuple elements with a custom separator::
 
-  std::string s = custom_format("{:x}", -42); // s == "ffffffd6"
+  #include <fmt/ranges.h>
 
-.. doxygenclass:: fmt::arg_formatter
-   :members:
+  std::tuple<int, char> t = {1, 'a'};
+  // Prints "1, a"
+  fmt::print("{}", fmt::join(t, ", "));
 
-.. _time-api:
+.. _chrono-api:
 
-Date and time formatting
+Date and Time Formatting
 ========================
 
 The library supports `strftime
 <http://en.cppreference.com/w/cpp/chrono/c/strftime>`_-like date and time
 formatting::
 
-  #include <fmt/time.h>
+  #include <fmt/chrono.h>
 
   std::time_t t = std::time(nullptr);
   // Prints "The date is 2016-04-29." (with the current date)
-  fmt::print("The date is {:%Y-%m-%d}.", *std::localtime(&t));
+  fmt::print("The date is {:%Y-%m-%d}.", fmt::localtime(t));
 
 The format string syntax is described in the documentation of
 `strftime <http://en.cppreference.com/w/cpp/chrono/c/strftime>`_.
 
+.. _compile-api:
+
+Format string compilation
+=========================
+
+``fmt/compile.h`` provides format string compilation support when using
+``FMT_COMPILE``. Format strings are parsed, checked and converted
+into efficient formatting code at compile-time.
+This supports arguments of built-in and string types as well as user-defined types
+with ``constexpr`` ``parse`` functions in their ``formatter`` specializations.
+Format string compilation can generate more binary code compared to the default
+API and is only recommended in places where formatting is a performance
+bottleneck.
+
+.. doxygendefine:: FMT_COMPILE
+
+.. _color-api:
+
+Terminal color and text style
+=============================
+
+``fmt/color.h`` provides support for terminal color and text style output.
+
+.. doxygenfunction:: print(const text_style&, const S&, const Args&...)
+
 .. _ostream-api:
 
-``std::ostream`` support
+``std::ostream`` Support
 ========================
 
 ``fmt/ostream.h`` provides ``std::ostream`` support including formatting of
@@ -344,7 +458,7 @@ user-defined types that have overloaded ``operator<<``::
   public:
     date(int year, int month, int day): year_(year), month_(month), day_(day) {}
 
-    friend std::ostream &operator<<(std::ostream &os, const date &d) {
+    friend std::ostream& operator<<(std::ostream& os, const date& d) {
       return os << d.year_ << '-' << d.month_ << '-' << d.day_;
     }
   };
@@ -352,11 +466,11 @@ user-defined types that have overloaded ``operator<<``::
   std::string s = fmt::format("The date is {}", date(2012, 12, 9));
   // s == "The date is 2012-12-9"
 
-.. doxygenfunction:: print(std::basic_ostream<fmt::char_t<S>>&, const S&, const Args&...)
+.. doxygenfunction:: print(std::basic_ostream<Char>&, const S&, Args&&...)
 
 .. _printf-api:
 
-``printf`` formatting
+``printf`` Formatting
 =====================
 
 The header ``fmt/printf.h`` provides ``printf``-like formatting functionality.
@@ -370,6 +484,22 @@ argument type doesn't match its format specification.
 
 .. doxygenfunction:: fprintf(std::FILE *, const S&, const Args&...)
 
-.. doxygenfunction:: fprintf(std::basic_ostream<fmt::char_t<S>>&, const S&, const Args&...)
+.. doxygenfunction:: fprintf(std::basic_ostream<Char>&, const S&, const Args&...)
 
 .. doxygenfunction:: sprintf(const S&, const Args&...)
+
+Compatibility with C++20 ``std::format``
+========================================
+
+{fmt} implements nearly all of the `C++20 formatting library
+<https://en.cppreference.com/w/cpp/utility/format>`_ with the following
+differences:
+
+* Names are defined in the ``fmt`` namespace instead of ``std`` to avoid
+  collisions with standard library implementations.
+* The ``'L'`` format specifier cannot be combined with presentation specifiers
+  yet.
+* Width calculation doesn't use grapheme clusterization. The latter has been
+  implemented in a separate branch but hasn't been integrated yet.
+* Chrono formatting doesn't support C++20 date types since they are not provided
+  by standard library implementations.

doc/build.py

@@ -6,20 +6,10 @@ import errno, os, shutil, sys, tempfile
 from subprocess import check_call, check_output, CalledProcessError, Popen, PIPE
 from distutils.version import LooseVersion
 
-versions = ['1.0.0', '1.1.0', '2.0.0', '3.0.2', '4.0.0', '4.1.0', '5.0.0', '5.1.0', '5.2.0', '5.2.1', '5.3.0']
+versions = ['1.0.0', '1.1.0', '2.0.0', '3.0.2', '4.0.0', '4.1.0', '5.0.0', '5.1.0', '5.2.0', '5.2.1', '5.3.0', '6.0.0', '6.1.0', '6.1.1', '6.1.2', '6.2.0', '6.2.1', '7.0.0', '7.0.1', '7.0.2', '7.0.3', '7.1.0', '7.1.1']
 
 def pip_install(package, commit=None, **kwargs):
   "Install package using pip."
-  min_version = kwargs.get('min_version')
-  if min_version:
-    from pkg_resources import get_distribution, DistributionNotFound
-    try:
-      installed_version = get_distribution(os.path.basename(package)).version
-      if LooseVersion(installed_version) >= min_version:
-        print('{} {} already installed'.format(package, min_version))
-        return
-    except DistributionNotFound:
-      pass
   if commit:
     package = 'git+https://github.com/{0}.git@{1}'.format(package, commit)
   print('Installing {0}'.format(package))
@@ -52,12 +42,11 @@ def create_build_env(dirname='virtualenv'):
       check_call(['pip', 'install', '--upgrade', 'distribute'])
   except DistributionNotFound:
     pass
-  # Install Sphinx and Breathe.
-  pip_install('sphinx-doc/sphinx', '12b83372ac9316e8cbe86e7fed889296a4cc29ee',
-              min_version='1.4.1.dev20160531')
+  # Install Sphinx and Breathe. Require the exact version of Sphinx which is
+  # compatible with Breathe.
+  pip_install('sphinx-doc/sphinx', '12b83372ac9316e8cbe86e7fed889296a4cc29ee')
   pip_install('michaeljones/breathe',
-              '129222318f7c8f865d2631e7da7b033567e7f56a',
-              min_version='4.2.0')
+              '129222318f7c8f865d2631e7da7b033567e7f56a')
 
 def build_docs(version='dev', **kwargs):
   doc_dir = kwargs.get('doc_dir', os.path.dirname(os.path.realpath(__file__)))
@@ -74,8 +63,8 @@ def build_docs(version='dev', **kwargs):
       GENERATE_MAN      = NO
       GENERATE_RTF      = NO
       CASE_SENSE_NAMES  = NO
-      INPUT             = {0}/core.h {0}/format.h {0}/ostream.h \
-                          {0}/printf.h {0}/time.h
+      INPUT             = {0}/chrono.h {0}/color.h {0}/core.h {0}/compile.h \
+                          {0}/format.h {0}/os.h {0}/ostream.h {0}/printf.h
       QUIET             = YES
       JAVADOC_AUTOBRIEF = YES
       AUTOLINK_SUPPORT  = NO
@@ -94,8 +83,9 @@ def build_docs(version='dev', **kwargs):
                           "FMT_BEGIN_NAMESPACE=namespace fmt {{" \
                           "FMT_END_NAMESPACE=}}" \
                           "FMT_STRING_ALIAS=1" \
-                          "FMT_ENABLE_IF_T(B, T)=T"
-      EXCLUDE_SYMBOLS   = fmt::internal::* StringValue write_str
+                          "FMT_ENABLE_IF(B)="
+      EXCLUDE_SYMBOLS   = fmt::formatter fmt::printf_formatter fmt::arg_join \
+                          fmt::basic_format_arg::handle
     '''.format(include_dir, doxyxml_dir).encode('UTF-8'))
   if p.returncode != 0:
     raise CalledProcessError(p.returncode, cmd)

doc/index.rst

@@ -1,17 +1,18 @@
 Overview
 ========
 
-**fmt** (formerly cppformat) is an open-source formatting library.
-It can be used as a fast and safe alternative to printf and IOStreams.
+**{fmt}** is an open-source formatting library providing a fast and safe
+alternative to C stdio and C++ iostreams.
 
 .. raw:: html
 
    <div class="panel panel-default">
      <div class="panel-heading">What users say:</div>
      <div class="panel-body">
-       Thanks for creating this library. It’s been a hole in C++ for a long
-       time. I’ve used both boost::format and loki::SPrintf, and neither felt
-       like the right answer. This does.
+       Thanks for creating this library. It’s been a hole in C++ for
+       a long time. I’ve used both <code>boost::format</code> and
+       <code>loki::SPrintf</code>, and neither felt like the right answer.
+       This does.
      </div>
    </div>
 
@@ -20,12 +21,13 @@ It can be used as a fast and safe alternative to printf and IOStreams.
 Format API
 ----------
 
-The replacement-based Format API provides a safe alternative to ``printf``,
-``sprintf`` and friends with comparable or `better performance
-<http://zverovich.net/2013/09/07/integer-to-string-conversion-in-cplusplus.html>`_.
+The format API is similar in spirit to the C ``printf`` family of function but
+is safer, simpler and several times `faster
+<https://www.zverovich.net/2020/06/13/fast-int-to-string-revisited.html>`_
+than common standard library implementations.
 The `format string syntax <syntax.html>`_ is similar to the one used by
-`str.format <http://docs.python.org/3/library/stdtypes.html#str.format>`_
-in Python:
+`str.format <http://docs.python.org/3/library/stdtypes.html#str.format>`_ in
+Python:
 
 .. code:: c++
 
@@ -46,21 +48,19 @@ The ``fmt::print`` function performs formatting and writes the result to a strea
 
   fmt::print(stderr, "System error code = {}\n", errno);
 
-The file argument can be omitted in which case the function prints to
-``stdout``:
+If you omit the file argument the function will print to ``stdout``:
 
 .. code:: c++
 
   fmt::print("Don't {}\n", "panic");
 
-The Format API also supports positional arguments useful for localization:
+The format API also supports positional arguments useful for localization:
 
 .. code:: c++
 
   fmt::print("I'd rather be {1} than {0}.", "right", "happy");
 
-Named arguments can be created with ``fmt::arg``. This makes it easier to track 
-what goes where when multiple values are being inserted:
+You can pass named arguments with ``fmt::arg``:
 
 .. code:: c++
 
@@ -72,21 +72,10 @@ an alternative, slightly terser syntax for named arguments:
 
 .. code:: c++
 
+  using namespace fmt::literals;
   fmt::print("Hello, {name}! The answer is {number}. Goodbye, {name}.",
              "name"_a="World", "number"_a=42);
 
-The ``_format`` suffix may be used to format string literals similar to Python:
-
-.. code:: c++
-
-  std::string message = "{0}{1}{0}"_format("abra", "cad"); 
-
-Other than the placement of the format string on the left of the operator, 
-``_format`` is functionally identical to ``fmt::format``. In order to use the 
-literal operators, they must be made visible with the directive 
-``using namespace fmt::literals;``. Note that this brings in only ``_a`` and 
-``_format`` but nothing else from the ``fmt`` namespace.
-
 .. _safety:
 
 Safety
@@ -100,16 +89,17 @@ time. For example, the code
 
   fmt::format("The answer is {:d}", "forty-two");
 
-throws a ``format_error`` exception with description "unknown format code 'd' for
-string", because the argument ``"forty-two"`` is a string while the format code
-``d`` only applies to integers, while
+throws the ``format_error`` exception because the argument ``"forty-two"`` is a
+string while the format code ``d`` only applies to integers.
+
+The code
 
 .. code:: c++
 
-  format(fmt("The answer is {:d}"), "forty-two");
+  format(FMT_STRING("The answer is {:d}"), "forty-two");
 
-reports a compile-time error for the same reason on compilers that support
-relaxed ``constexpr``.
+reports a compile-time error on compilers that support relaxed ``constexpr``.
+See `here <api.html#c.fmt>`_ for details.
 
 The following code
 
@@ -126,13 +116,13 @@ formatted into a narrow string. You can use a wide format string instead:
 
 For comparison, writing a wide character to ``std::ostream`` results in
 its numeric value being written to the stream (i.e. 1070 instead of letter 'ю'
-which is represented by ``L'\x42e'`` if we use Unicode) which is rarely what is
-needed.
+which is represented by ``L'\x42e'`` if we use Unicode) which is rarely
+desirable.
 
-Compact binary code
+Compact Binary Code
 -------------------
 
-The library is designed to produce compact per-call compiled code. For example
+The library produces compact per-call compiled code. For example
 (`godbolt <https://godbolt.org/g/TZU4KF>`_),
 
 .. code:: c++
@@ -153,8 +143,8 @@ compiles to just
      mov rcx, rsp
      mov edi, offset .L.str
      mov esi, 17
-     mov edx, 2
-     call fmt::v5::vprint(fmt::v5::basic_string_view<char>, fmt::v5::format_args)
+     mov edx, 1
+     call fmt::v7::vprint(fmt::v7::basic_string_view<char>, fmt::v7::format_args)
      xor eax, eax
      add rsp, 24
      ret
@@ -174,30 +164,30 @@ The library is highly portable and relies only on a small set of C++11 features:
 * decltype
 * trailing return types
 * deleted functions
+* alias templates
 
-These are available since GCC 4.4, Clang 2.9 and MSVC 18.0 (2013). For older
-compilers use fmt `version 4.x
-<https://github.com/fmtlib/fmt/releases/tag/4.1.0>`_ which continues to be
-maintained and only requires C++98.
+These are available in GCC 4.8, Clang 3.0, MSVC 19.0 (2015) and more recent
+compiler version. For older compilers use {fmt} `version 4.x
+<https://github.com/fmtlib/fmt/releases/tag/4.1.0>`_ which is maintained and
+only requires C++98.
 
-The output of all formatting functions is consistent across platforms. In
-particular, formatting a floating-point infinity always gives ``inf`` while the
-output of ``printf`` is platform-dependent in this case. For example,
+The output of all formatting functions is consistent across platforms.
+For example,
 
 .. code::
 
   fmt::print("{}", std::numeric_limits<double>::infinity());
 
-always prints ``inf``.
+always prints ``inf`` while the output of ``printf`` is platform-dependent.
 
 .. _ease-of-use:
 
 Ease of Use
 -----------
 
-fmt has a small self-contained code base with the core library consisting of
+{fmt} has a small self-contained code base with the core library consisting of
 just three header files and no external dependencies.
-A permissive BSD `license <https://github.com/fmtlib/fmt#license>`_ allows
+A permissive MIT `license <https://github.com/fmtlib/fmt#license>`_ allows
 using the library both in open-source and commercial projects.
 
 .. raw:: html

doc/syntax.rst

@@ -76,19 +76,19 @@ The general form of a *standard format specifier* is:
 
 .. productionlist:: sf
    format_spec: [[`fill`]`align`][`sign`]["#"]["0"][`width`]["." `precision`][`type`]
-   fill: <a character other than '{', '}' or '\0'>
-   align: "<" | ">" | "=" | "^"
+   fill: <a character other than '{' or '}'>
+   align: "<" | ">" | "^"
    sign: "+" | "-" | " "
-   width: `integer` | "{" `arg_id` "}"
-   precision: `integer` | "{" `arg_id` "}"
-   type: `int_type` | "a" | "A" | "c" | "e" | "E" | "f" | "F" | "g" | "G" | "p" | "s"
-   int_type: "b" | "B" | "d" | "n" | "o" | "x" | "X"
+   width: `integer` | "{" [`arg_id`] "}"
+   precision: `integer` | "{" [`arg_id`] "}"
+   type: `int_type` | "a" | "A" | "c" | "e" | "E" | "f" | "F" | "g" | "G" | "L" | "p" | "s"
+   int_type: "b" | "B" | "d" | "o" | "x" | "X"
 
-The *fill* character can be any character other than '{', '}' or '\\0'. The
-presence of a fill character is signaled by the character following it, which
-must be one of the alignment options.  If the second character of *format_spec*
-is not a valid alignment option, then it is assumed that both the fill character
-and the alignment option are absent.
+The *fill* character can be any Unicode code point other than ``'{'`` or
+``'}'``. The presence of a fill character is signaled by the character following
+it, which must be one of the alignment options. If the second character of
+*format_spec* is not a valid alignment option, then it is assumed that both the
+fill character and the alignment option are absent.
 
 The meaning of the various alignment options is as follows:
 
@@ -101,11 +101,6 @@ The meaning of the various alignment options is as follows:
 | ``'>'`` | Forces the field to be right-aligned within the          |
 |         | available space (this is the default for numbers).       |
 +---------+----------------------------------------------------------+
-| ``'='`` | Forces the padding to be placed after the sign (if any)  |
-|         | but before the digits.  This is used for printing fields |
-|         | in the form '+000000120'. This alignment option is only  |
-|         | valid for numeric types.                                 |
-+---------+----------------------------------------------------------+
 | ``'^'`` | Forces the field to be centered within the available     |
 |         | space.                                                   |
 +---------+----------------------------------------------------------+
@@ -148,15 +143,17 @@ conversions, trailing zeros are not removed from the result.
 .. ifconfig:: False
 
    The ``','`` option signals the use of a comma for a thousands separator.
-   For a locale aware separator, use the ``'n'`` integer presentation type
+   For a locale aware separator, use the ``'L'`` integer presentation type
    instead.
 
 *width* is a decimal integer defining the minimum field width.  If not
 specified, then the field width will be determined by the content.
 
-Preceding the *width* field by a zero (``'0'``) character enables
-sign-aware zero-padding for numeric types.  This is equivalent to a *fill*
-character of ``'0'`` with an *alignment* type of ``'='``.
+Preceding the *width* field by a zero (``'0'``) character enables sign-aware
+zero-padding for numeric types. It forces the padding to be placed after the
+sign or base (if any) but before the digits. This is used for printing fields in
+the form '+000000120'. This option is only valid for numeric types and it has no
+effect on formatting of infinity and NaN.
 
 The *precision* is a decimal number indicating how many digits should be
 displayed after the decimal point for a floating-point value formatted with
@@ -217,9 +214,9 @@ The available integer presentation types are:
 |         | ``'#'`` option with this type adds the prefix ``"0X"``   |
 |         | to the output value.                                     |
 +---------+----------------------------------------------------------+
-| ``'n'`` | Number. This is the same as ``'d'``, except that it uses |
-|         | the current locale setting to insert the appropriate     |
-|         | number separator characters.                             |
+| ``'L'`` | Locale-specific format. This is the same as ``'d'``,     |
+|         | except that it uses the current locale setting to insert |
+|         | the appropriate number separator characters.             |
 +---------+----------------------------------------------------------+
 | none    | The same as ``'d'``.                                     |
 +---------+----------------------------------------------------------+
@@ -244,7 +241,7 @@ The available presentation types for floating-point values are:
 |         | notation using the letter 'e' to indicate the exponent.  |
 +---------+----------------------------------------------------------+
 | ``'E'`` | Exponent notation. Same as ``'e'`` except it uses an     |
-|         | upper-case 'E' as the separator character.               |
+|         | upper-case ``'E'`` as the separator character.           |
 +---------+----------------------------------------------------------+
 | ``'f'`` | Fixed point. Displays the number as a fixed-point        |
 |         | number.                                                  |
@@ -264,10 +261,15 @@ The available presentation types for floating-point values are:
 |         | ``'E'`` if the number gets too large. The                |
 |         | representations of infinity and NaN are uppercased, too. |
 +---------+----------------------------------------------------------+
-| none    | The same as ``'g'``.                                     |
+| ``'L'`` | Locale-specific format. This is the same as ``'g'``,     |
+|         | except that it uses the current locale setting to insert |
+|         | the appropriate number separator characters.             |
++---------+----------------------------------------------------------+
+| none    | Similar to ``'g'``, except that fixed-point notation,    |
+|         | when used, has at least one digit past the decimal       |
+|         | point. The default precision is as high as needed to     |
+|         | represent the particular value.                          |
 +---------+----------------------------------------------------------+
-
-Floating-point formatting is locale-dependent.
 
 .. ifconfig:: False
 
@@ -303,7 +305,7 @@ The available presentation types for pointers are:
 
 .. _formatexamples:
 
-Format examples
+Format Examples
 ===============
 
 This section contains examples of the format syntax and comparison with
@@ -318,72 +320,94 @@ following examples.
 
 Accessing arguments by position::
 
-   format("{0}, {1}, {2}", 'a', 'b', 'c');
+   fmt::format("{0}, {1}, {2}", 'a', 'b', 'c');
    // Result: "a, b, c"
-   format("{}, {}, {}", 'a', 'b', 'c');
+   fmt::format("{}, {}, {}", 'a', 'b', 'c');
    // Result: "a, b, c"
-   format("{2}, {1}, {0}", 'a', 'b', 'c');
+   fmt::format("{2}, {1}, {0}", 'a', 'b', 'c');
    // Result: "c, b, a"
-   format("{0}{1}{0}", "abra", "cad");  // arguments' indices can be repeated
+   fmt::format("{0}{1}{0}", "abra", "cad");  // arguments' indices can be repeated
    // Result: "abracadabra"
 
 Aligning the text and specifying a width::
 
-   format("{:<30}", "left aligned");
+   fmt::format("{:<30}", "left aligned");
    // Result: "left aligned                  "
-   format("{:>30}", "right aligned");
+   fmt::format("{:>30}", "right aligned");
    // Result: "                 right aligned"
-   format("{:^30}", "centered");
+   fmt::format("{:^30}", "centered");
    // Result: "           centered           "
-   format("{:*^30}", "centered");  // use '*' as a fill char
+   fmt::format("{:*^30}", "centered");  // use '*' as a fill char
    // Result: "***********centered***********"
 
 Dynamic width::
 
-   format("{:<{}}", "left aligned", 30);
+   fmt::format("{:<{}}", "left aligned", 30);
    // Result: "left aligned                  "
 
 Dynamic precision::
 
-   format("{:.{}f}", 3.14, 1);
+   fmt::format("{:.{}f}", 3.14, 1);
    // Result: "3.1"
 
 Replacing ``%+f``, ``%-f``, and ``% f`` and specifying a sign::
 
-   format("{:+f}; {:+f}", 3.14, -3.14);  // show it always
+   fmt::format("{:+f}; {:+f}", 3.14, -3.14);  // show it always
    // Result: "+3.140000; -3.140000"
-   format("{: f}; {: f}", 3.14, -3.14);  // show a space for positive numbers
+   fmt::format("{: f}; {: f}", 3.14, -3.14);  // show a space for positive numbers
    // Result: " 3.140000; -3.140000"
-   format("{:-f}; {:-f}", 3.14, -3.14);  // show only the minus -- same as '{:f}; {:f}'
+   fmt::format("{:-f}; {:-f}", 3.14, -3.14);  // show only the minus -- same as '{:f}; {:f}'
    // Result: "3.140000; -3.140000"
 
 Replacing ``%x`` and ``%o`` and converting the value to different bases::
 
-   format("int: {0:d};  hex: {0:x};  oct: {0:o}; bin: {0:b}", 42);
+   fmt::format("int: {0:d};  hex: {0:x};  oct: {0:o}; bin: {0:b}", 42);
    // Result: "int: 42;  hex: 2a;  oct: 52; bin: 101010"
    // with 0x or 0 or 0b as prefix:
-   format("int: {0:d};  hex: {0:#x};  oct: {0:#o};  bin: {0:#b}", 42);
+   fmt::format("int: {0:d};  hex: {0:#x};  oct: {0:#o};  bin: {0:#b}", 42);
    // Result: "int: 42;  hex: 0x2a;  oct: 052;  bin: 0b101010"
 
 Padded hex byte with prefix and always prints both hex characters::
 
-   format("{:#04x}", 0);
+   fmt::format("{:#04x}", 0);
    // Result: "0x00"
 
+Box drawing using Unicode fill::
+
+   fmt::print(
+     "┌{0:─^{2}}┐\n"
+     "│{1: ^{2}}│\n"
+     "└{0:─^{2}}┘\n", "", "Hello, world!", 20);
+
+prints::
+
+   ┌────────────────────┐
+   │   Hello, world!    │
+   └────────────────────┘
+
+Using type-specific formatting::
+
+   #include <fmt/chrono.h>
+
+   auto t = tm();
+   t.tm_year = 2010 - 1900;
+   t.tm_mon = 6;
+   t.tm_mday = 4;
+   t.tm_hour = 12;
+   t.tm_min = 15;
+   t.tm_sec = 58;
+   fmt::print("{:%Y-%m-%d %H:%M:%S}", t);
+   // Prints: 2010-08-04 12:15:58
+
+Using the comma as a thousands separator::
+
+   #include <fmt/locale.h>
+
+   auto s = fmt::format(std::locale("en_US.UTF-8"), "{:L}", 1234567890);
+   // s == "1,234,567,890"
+
 .. ifconfig:: False
 
-   Using the comma as a thousands separator::
-
-      format("{:,}", 1234567890);
-      '1,234,567,890'
-
-   Using type-specific formatting::
-
-      >>> import datetime
-      >>> d = datetime.datetime(2010, 7, 4, 12, 15, 58)
-      Format("{:%Y-%m-%d %H:%M:%S}") << d)
-      '2010-07-04 12:15:58'
-
    Nesting arguments and more complex examples::
 
       >>> for align, text in zip('<^>', ['left', 'center', 'right']):
@@ -412,4 +436,3 @@ Padded hex byte with prefix and always prints both hex characters::
           9     9    11  1001
          10     A    12  1010
          11     B    13  1011
-

doc/usage.rst

@@ -2,21 +2,15 @@
 Usage
 *****
 
-To use the fmt library, add :file:`format.h` and :file:`format.cc` from
-a `release archive <https://github.com/fmtlib/fmt/releases/latest>`_
-or the `Git repository <https://github.com/fmtlib/fmt>`_ to your project.
+To use the {fmt} library, add :file:`fmt/core.h`, :file:`fmt/format.h`,
+:file:`fmt/format-inl.h`, :file:`src/format.cc` and optionally other headers
+from a `release archive <https://github.com/fmtlib/fmt/releases/latest>`_ or
+the `Git repository <https://github.com/fmtlib/fmt>`_ to your project.
 Alternatively, you can :ref:`build the library with CMake <building>`.
 
-If you are using Visual C++ with precompiled headers, you might need to add
-the line ::
-
-   #include "stdafx.h"
-
-before other includes in :file:`format.cc`.
-
 .. _building:
 
-Building the library
+Building the Library
 ====================
 
 The included `CMake build script`__ can be used to build the fmt
@@ -31,7 +25,7 @@ workflow starts with::
 
   mkdir build          # Create a directory to hold the build output.
   cd build
-  cmake <path/to/fmt>  # Generate native build scripts.
+  cmake ..  # Generate native build scripts.
 
 where :file:`{<path/to/fmt>}` is a path to the ``fmt`` repository.
 
@@ -58,8 +52,22 @@ To build a `shared library`__ set the ``BUILD_SHARED_LIBS`` CMake variable to
 
 __ http://en.wikipedia.org/wiki/Library_%28computing%29#Shared_libraries
 
-Header-only usage with CMake
-============================
+
+To build a `static library` with position independent code (required if the main
+consumer of the fmt library is a shared library i.e. a Python extension) set the
+``CMAKE_POSITION_INDEPENDENT_CODE`` CMake variable to ``TRUE``::
+
+  cmake -DCMAKE_POSITION_INDEPENDENT_CODE=TRUE ...
+
+
+Installing the Library
+======================
+
+After building the library you can install it on a Unix-like system by running
+:command:`sudo make install`.
+
+Usage with CMake
+================
 
 You can add the ``fmt`` library directory into your project and include it in
 your ``CMakeLists.txt`` file::
@@ -79,11 +87,54 @@ You can detect and use an installed version of {fmt} as follows::
    find_package(fmt)
    target_link_libraries(<your-target> fmt::fmt)
 
-Setting up your target to use a header-only version of ``fmt`` is equaly easy::
+Setting up your target to use a header-only version of ``fmt`` is equally easy::
 
-   target_link_libraries(<your-target> PRIVATE fmt-header-only)
+   target_link_libraries(<your-target> PRIVATE fmt::fmt-header-only)
 
-Building the documentation
+Usage with build2
+=================
+
+You can use `build2 <https://build2.org>`_, a dependency manager and a
+build-system combined, to use ``fmt``.
+
+Currently this package is available in these package repositories:
+
+- **https://cppget.org/fmt/** for released and published versions.
+- `The git repository with the sources of the build2 package of fmt <https://github.com/build2-packaging/fmt.git>`_
+  for unreleased or custom revisions of ``fmt``.
+
+**Usage:**
+
+- ``build2`` package name: ``fmt``
+- Library target name : ``lib{fmt}``
+
+For example, to make your ``build2`` project depend on ``fmt``:
+
+- Add one of the repositories to your configurations, or in your
+  ``repositories.manifest``, if not already there::
+
+    :
+    role: prerequisite
+    location: https://pkg.cppget.org/1/stable
+
+- Add this package as a dependency to your ``./manifest`` file
+  (example for ``v7.0.x``)::
+
+    depends: fmt ~7.0.0
+
+- Import the target and use it as a prerequisite to your own target
+  using `fmt` in the appropriate ``buildfile``::
+
+    import fmt = fmt%lib{fmt}
+    lib{mylib} : cxx{**} ... $fmt
+
+Then build your project as usual with `b` or `bdep update`.
+
+For ``build2`` newcomers or to get more details and use cases, you can read the
+``build2``
+`toolchain introduction <https://build2.org/build2-toolchain/doc/build2-toolchain-intro.xhtml>`_.
+
+Building the Documentation
 ==========================
 
 To build the documentation you need the following software installed on your
@@ -103,7 +154,45 @@ the previous section. Then compile the ``doc`` target/project, for example::
   make doc
 
 This will generate the HTML documentation in ``doc/html``.
-  
+
+Conda
+=====
+
+fmt can be installed on Linux, macOS and Windows with
+`Conda <https://docs.conda.io/en/latest/>`__, using its
+`conda-forge <https://conda-forge.org>`__
+`package <https://github.com/conda-forge/fmt-feedstock>`__, as follows::
+
+  conda install -c conda-forge fmt
+
+Vcpkg
+=====
+
+You can download and install fmt using the `vcpkg
+<https://github.com/Microsoft/vcpkg>`__ dependency manager::
+
+  git clone https://github.com/Microsoft/vcpkg.git
+  cd vcpkg
+  ./bootstrap-vcpkg.sh
+  ./vcpkg integrate install
+  ./vcpkg install fmt
+
+The fmt port in vcpkg is kept up to date by Microsoft team members and community
+contributors. If the version is out of date, please `create an issue or pull
+request <https://github.com/Microsoft/vcpkg>`__ on the vcpkg repository.
+
+LHelper
+=======
+
+You can download and install fmt using
+`lhelper <https://github.com/franko/lhelper>`__ dependency manager::
+
+  lhelper activate <some-environment>
+  lhelper install fmt
+
+All the recipes for lhelper are kept in the
+`lhelper's recipe <https://github.com/franko/lhelper-recipes>`__ repository.
+
 Android NDK
 ===========
 

include/fmt/color.h

@@ -12,184 +12,149 @@
 
 FMT_BEGIN_NAMESPACE
 
-#ifdef FMT_DEPRECATED_COLORS
-
-// color and (v)print_colored are deprecated.
-enum color { black, red, green, yellow, blue, magenta, cyan, white };
-FMT_API void vprint_colored(color c, string_view format, format_args args);
-FMT_API void vprint_colored(color c, wstring_view format, wformat_args args);
-template <typename... Args>
-inline void print_colored(color c, string_view format_str,
-                          const Args & ... args) {
-  vprint_colored(c, format_str, make_format_args(args...));
-}
-template <typename... Args>
-inline void print_colored(color c, wstring_view format_str,
-                          const Args & ... args) {
-  vprint_colored(c, format_str, make_format_args<wformat_context>(args...));
-}
-
-inline void vprint_colored(color c, string_view format, format_args args) {
-  char escape[] = "\x1b[30m";
-  escape[3] = static_cast<char>('0' + c);
-  std::fputs(escape, stdout);
-  vprint(format, args);
-  std::fputs(internal::data::RESET_COLOR, stdout);
-}
-
-inline void vprint_colored(color c, wstring_view format, wformat_args args) {
-  wchar_t escape[] = L"\x1b[30m";
-  escape[3] = static_cast<wchar_t>('0' + c);
-  std::fputws(escape, stdout);
-  vprint(format, args);
-  std::fputws(internal::data::WRESET_COLOR, stdout);
-}
-
-#else
-
 enum class color : uint32_t {
-  alice_blue              = 0xF0F8FF, // rgb(240,248,255)
-  antique_white           = 0xFAEBD7, // rgb(250,235,215)
-  aqua                    = 0x00FFFF, // rgb(0,255,255)
-  aquamarine              = 0x7FFFD4, // rgb(127,255,212)
-  azure                   = 0xF0FFFF, // rgb(240,255,255)
-  beige                   = 0xF5F5DC, // rgb(245,245,220)
-  bisque                  = 0xFFE4C4, // rgb(255,228,196)
-  black                   = 0x000000, // rgb(0,0,0)
-  blanched_almond         = 0xFFEBCD, // rgb(255,235,205)
-  blue                    = 0x0000FF, // rgb(0,0,255)
-  blue_violet             = 0x8A2BE2, // rgb(138,43,226)
-  brown                   = 0xA52A2A, // rgb(165,42,42)
-  burly_wood              = 0xDEB887, // rgb(222,184,135)
-  cadet_blue              = 0x5F9EA0, // rgb(95,158,160)
-  chartreuse              = 0x7FFF00, // rgb(127,255,0)
-  chocolate               = 0xD2691E, // rgb(210,105,30)
-  coral                   = 0xFF7F50, // rgb(255,127,80)
-  cornflower_blue         = 0x6495ED, // rgb(100,149,237)
-  cornsilk                = 0xFFF8DC, // rgb(255,248,220)
-  crimson                 = 0xDC143C, // rgb(220,20,60)
-  cyan                    = 0x00FFFF, // rgb(0,255,255)
-  dark_blue               = 0x00008B, // rgb(0,0,139)
-  dark_cyan               = 0x008B8B, // rgb(0,139,139)
-  dark_golden_rod         = 0xB8860B, // rgb(184,134,11)
-  dark_gray               = 0xA9A9A9, // rgb(169,169,169)
-  dark_green              = 0x006400, // rgb(0,100,0)
-  dark_khaki              = 0xBDB76B, // rgb(189,183,107)
-  dark_magenta            = 0x8B008B, // rgb(139,0,139)
-  dark_olive_green        = 0x556B2F, // rgb(85,107,47)
-  dark_orange             = 0xFF8C00, // rgb(255,140,0)
-  dark_orchid             = 0x9932CC, // rgb(153,50,204)
-  dark_red                = 0x8B0000, // rgb(139,0,0)
-  dark_salmon             = 0xE9967A, // rgb(233,150,122)
-  dark_sea_green          = 0x8FBC8F, // rgb(143,188,143)
-  dark_slate_blue         = 0x483D8B, // rgb(72,61,139)
-  dark_slate_gray         = 0x2F4F4F, // rgb(47,79,79)
-  dark_turquoise          = 0x00CED1, // rgb(0,206,209)
-  dark_violet             = 0x9400D3, // rgb(148,0,211)
-  deep_pink               = 0xFF1493, // rgb(255,20,147)
-  deep_sky_blue           = 0x00BFFF, // rgb(0,191,255)
-  dim_gray                = 0x696969, // rgb(105,105,105)
-  dodger_blue             = 0x1E90FF, // rgb(30,144,255)
-  fire_brick              = 0xB22222, // rgb(178,34,34)
-  floral_white            = 0xFFFAF0, // rgb(255,250,240)
-  forest_green            = 0x228B22, // rgb(34,139,34)
-  fuchsia                 = 0xFF00FF, // rgb(255,0,255)
-  gainsboro               = 0xDCDCDC, // rgb(220,220,220)
-  ghost_white             = 0xF8F8FF, // rgb(248,248,255)
-  gold                    = 0xFFD700, // rgb(255,215,0)
-  golden_rod              = 0xDAA520, // rgb(218,165,32)
-  gray                    = 0x808080, // rgb(128,128,128)
-  green                   = 0x008000, // rgb(0,128,0)
-  green_yellow            = 0xADFF2F, // rgb(173,255,47)
-  honey_dew               = 0xF0FFF0, // rgb(240,255,240)
-  hot_pink                = 0xFF69B4, // rgb(255,105,180)
-  indian_red              = 0xCD5C5C, // rgb(205,92,92)
-  indigo                  = 0x4B0082, // rgb(75,0,130)
-  ivory                   = 0xFFFFF0, // rgb(255,255,240)
-  khaki                   = 0xF0E68C, // rgb(240,230,140)
-  lavender                = 0xE6E6FA, // rgb(230,230,250)
-  lavender_blush          = 0xFFF0F5, // rgb(255,240,245)
-  lawn_green              = 0x7CFC00, // rgb(124,252,0)
-  lemon_chiffon           = 0xFFFACD, // rgb(255,250,205)
-  light_blue              = 0xADD8E6, // rgb(173,216,230)
-  light_coral             = 0xF08080, // rgb(240,128,128)
-  light_cyan              = 0xE0FFFF, // rgb(224,255,255)
-  light_golden_rod_yellow = 0xFAFAD2, // rgb(250,250,210)
-  light_gray              = 0xD3D3D3, // rgb(211,211,211)
-  light_green             = 0x90EE90, // rgb(144,238,144)
-  light_pink              = 0xFFB6C1, // rgb(255,182,193)
-  light_salmon            = 0xFFA07A, // rgb(255,160,122)
-  light_sea_green         = 0x20B2AA, // rgb(32,178,170)
-  light_sky_blue          = 0x87CEFA, // rgb(135,206,250)
-  light_slate_gray        = 0x778899, // rgb(119,136,153)
-  light_steel_blue        = 0xB0C4DE, // rgb(176,196,222)
-  light_yellow            = 0xFFFFE0, // rgb(255,255,224)
-  lime                    = 0x00FF00, // rgb(0,255,0)
-  lime_green              = 0x32CD32, // rgb(50,205,50)
-  linen                   = 0xFAF0E6, // rgb(250,240,230)
-  magenta                 = 0xFF00FF, // rgb(255,0,255)
-  maroon                  = 0x800000, // rgb(128,0,0)
-  medium_aquamarine       = 0x66CDAA, // rgb(102,205,170)
-  medium_blue             = 0x0000CD, // rgb(0,0,205)
-  medium_orchid           = 0xBA55D3, // rgb(186,85,211)
-  medium_purple           = 0x9370DB, // rgb(147,112,219)
-  medium_sea_green        = 0x3CB371, // rgb(60,179,113)
-  medium_slate_blue       = 0x7B68EE, // rgb(123,104,238)
-  medium_spring_green     = 0x00FA9A, // rgb(0,250,154)
-  medium_turquoise        = 0x48D1CC, // rgb(72,209,204)
-  medium_violet_red       = 0xC71585, // rgb(199,21,133)
-  midnight_blue           = 0x191970, // rgb(25,25,112)
-  mint_cream              = 0xF5FFFA, // rgb(245,255,250)
-  misty_rose              = 0xFFE4E1, // rgb(255,228,225)
-  moccasin                = 0xFFE4B5, // rgb(255,228,181)
-  navajo_white            = 0xFFDEAD, // rgb(255,222,173)
-  navy                    = 0x000080, // rgb(0,0,128)
-  old_lace                = 0xFDF5E6, // rgb(253,245,230)
-  olive                   = 0x808000, // rgb(128,128,0)
-  olive_drab              = 0x6B8E23, // rgb(107,142,35)
-  orange                  = 0xFFA500, // rgb(255,165,0)
-  orange_red              = 0xFF4500, // rgb(255,69,0)
-  orchid                  = 0xDA70D6, // rgb(218,112,214)
-  pale_golden_rod         = 0xEEE8AA, // rgb(238,232,170)
-  pale_green              = 0x98FB98, // rgb(152,251,152)
-  pale_turquoise          = 0xAFEEEE, // rgb(175,238,238)
-  pale_violet_red         = 0xDB7093, // rgb(219,112,147)
-  papaya_whip             = 0xFFEFD5, // rgb(255,239,213)
-  peach_puff              = 0xFFDAB9, // rgb(255,218,185)
-  peru                    = 0xCD853F, // rgb(205,133,63)
-  pink                    = 0xFFC0CB, // rgb(255,192,203)
-  plum                    = 0xDDA0DD, // rgb(221,160,221)
-  powder_blue             = 0xB0E0E6, // rgb(176,224,230)
-  purple                  = 0x800080, // rgb(128,0,128)
-  rebecca_purple          = 0x663399, // rgb(102,51,153)
-  red                     = 0xFF0000, // rgb(255,0,0)
-  rosy_brown              = 0xBC8F8F, // rgb(188,143,143)
-  royal_blue              = 0x4169E1, // rgb(65,105,225)
-  saddle_brown            = 0x8B4513, // rgb(139,69,19)
-  salmon                  = 0xFA8072, // rgb(250,128,114)
-  sandy_brown             = 0xF4A460, // rgb(244,164,96)
-  sea_green               = 0x2E8B57, // rgb(46,139,87)
-  sea_shell               = 0xFFF5EE, // rgb(255,245,238)
-  sienna                  = 0xA0522D, // rgb(160,82,45)
-  silver                  = 0xC0C0C0, // rgb(192,192,192)
-  sky_blue                = 0x87CEEB, // rgb(135,206,235)
-  slate_blue              = 0x6A5ACD, // rgb(106,90,205)
-  slate_gray              = 0x708090, // rgb(112,128,144)
-  snow                    = 0xFFFAFA, // rgb(255,250,250)
-  spring_green            = 0x00FF7F, // rgb(0,255,127)
-  steel_blue              = 0x4682B4, // rgb(70,130,180)
-  tan                     = 0xD2B48C, // rgb(210,180,140)
-  teal                    = 0x008080, // rgb(0,128,128)
-  thistle                 = 0xD8BFD8, // rgb(216,191,216)
-  tomato                  = 0xFF6347, // rgb(255,99,71)
-  turquoise               = 0x40E0D0, // rgb(64,224,208)
-  violet                  = 0xEE82EE, // rgb(238,130,238)
-  wheat                   = 0xF5DEB3, // rgb(245,222,179)
-  white                   = 0xFFFFFF, // rgb(255,255,255)
-  white_smoke             = 0xF5F5F5, // rgb(245,245,245)
-  yellow                  = 0xFFFF00, // rgb(255,255,0)
-  yellow_green            = 0x9ACD32  // rgb(154,205,50)
-};  // enum class color
+  alice_blue = 0xF0F8FF,               // rgb(240,248,255)
+  antique_white = 0xFAEBD7,            // rgb(250,235,215)
+  aqua = 0x00FFFF,                     // rgb(0,255,255)
+  aquamarine = 0x7FFFD4,               // rgb(127,255,212)
+  azure = 0xF0FFFF,                    // rgb(240,255,255)
+  beige = 0xF5F5DC,                    // rgb(245,245,220)
+  bisque = 0xFFE4C4,                   // rgb(255,228,196)
+  black = 0x000000,                    // rgb(0,0,0)
+  blanched_almond = 0xFFEBCD,          // rgb(255,235,205)
+  blue = 0x0000FF,                     // rgb(0,0,255)
+  blue_violet = 0x8A2BE2,              // rgb(138,43,226)
+  brown = 0xA52A2A,                    // rgb(165,42,42)
+  burly_wood = 0xDEB887,               // rgb(222,184,135)
+  cadet_blue = 0x5F9EA0,               // rgb(95,158,160)
+  chartreuse = 0x7FFF00,               // rgb(127,255,0)
+  chocolate = 0xD2691E,                // rgb(210,105,30)
+  coral = 0xFF7F50,                    // rgb(255,127,80)
+  cornflower_blue = 0x6495ED,          // rgb(100,149,237)
+  cornsilk = 0xFFF8DC,                 // rgb(255,248,220)
+  crimson = 0xDC143C,                  // rgb(220,20,60)
+  cyan = 0x00FFFF,                     // rgb(0,255,255)
+  dark_blue = 0x00008B,                // rgb(0,0,139)
+  dark_cyan = 0x008B8B,                // rgb(0,139,139)
+  dark_golden_rod = 0xB8860B,          // rgb(184,134,11)
+  dark_gray = 0xA9A9A9,                // rgb(169,169,169)
+  dark_green = 0x006400,               // rgb(0,100,0)
+  dark_khaki = 0xBDB76B,               // rgb(189,183,107)
+  dark_magenta = 0x8B008B,             // rgb(139,0,139)
+  dark_olive_green = 0x556B2F,         // rgb(85,107,47)
+  dark_orange = 0xFF8C00,              // rgb(255,140,0)
+  dark_orchid = 0x9932CC,              // rgb(153,50,204)
+  dark_red = 0x8B0000,                 // rgb(139,0,0)
+  dark_salmon = 0xE9967A,              // rgb(233,150,122)
+  dark_sea_green = 0x8FBC8F,           // rgb(143,188,143)
+  dark_slate_blue = 0x483D8B,          // rgb(72,61,139)
+  dark_slate_gray = 0x2F4F4F,          // rgb(47,79,79)
+  dark_turquoise = 0x00CED1,           // rgb(0,206,209)
+  dark_violet = 0x9400D3,              // rgb(148,0,211)
+  deep_pink = 0xFF1493,                // rgb(255,20,147)
+  deep_sky_blue = 0x00BFFF,            // rgb(0,191,255)
+  dim_gray = 0x696969,                 // rgb(105,105,105)
+  dodger_blue = 0x1E90FF,              // rgb(30,144,255)
+  fire_brick = 0xB22222,               // rgb(178,34,34)
+  floral_white = 0xFFFAF0,             // rgb(255,250,240)
+  forest_green = 0x228B22,             // rgb(34,139,34)
+  fuchsia = 0xFF00FF,                  // rgb(255,0,255)
+  gainsboro = 0xDCDCDC,                // rgb(220,220,220)
+  ghost_white = 0xF8F8FF,              // rgb(248,248,255)
+  gold = 0xFFD700,                     // rgb(255,215,0)
+  golden_rod = 0xDAA520,               // rgb(218,165,32)
+  gray = 0x808080,                     // rgb(128,128,128)
+  green = 0x008000,                    // rgb(0,128,0)
+  green_yellow = 0xADFF2F,             // rgb(173,255,47)
+  honey_dew = 0xF0FFF0,                // rgb(240,255,240)
+  hot_pink = 0xFF69B4,                 // rgb(255,105,180)
+  indian_red = 0xCD5C5C,               // rgb(205,92,92)
+  indigo = 0x4B0082,                   // rgb(75,0,130)
+  ivory = 0xFFFFF0,                    // rgb(255,255,240)
+  khaki = 0xF0E68C,                    // rgb(240,230,140)
+  lavender = 0xE6E6FA,                 // rgb(230,230,250)
+  lavender_blush = 0xFFF0F5,           // rgb(255,240,245)
+  lawn_green = 0x7CFC00,               // rgb(124,252,0)
+  lemon_chiffon = 0xFFFACD,            // rgb(255,250,205)
+  light_blue = 0xADD8E6,               // rgb(173,216,230)
+  light_coral = 0xF08080,              // rgb(240,128,128)
+  light_cyan = 0xE0FFFF,               // rgb(224,255,255)
+  light_golden_rod_yellow = 0xFAFAD2,  // rgb(250,250,210)
+  light_gray = 0xD3D3D3,               // rgb(211,211,211)
+  light_green = 0x90EE90,              // rgb(144,238,144)
+  light_pink = 0xFFB6C1,               // rgb(255,182,193)
+  light_salmon = 0xFFA07A,             // rgb(255,160,122)
+  light_sea_green = 0x20B2AA,          // rgb(32,178,170)
+  light_sky_blue = 0x87CEFA,           // rgb(135,206,250)
+  light_slate_gray = 0x778899,         // rgb(119,136,153)
+  light_steel_blue = 0xB0C4DE,         // rgb(176,196,222)
+  light_yellow = 0xFFFFE0,             // rgb(255,255,224)
+  lime = 0x00FF00,                     // rgb(0,255,0)
+  lime_green = 0x32CD32,               // rgb(50,205,50)
+  linen = 0xFAF0E6,                    // rgb(250,240,230)
+  magenta = 0xFF00FF,                  // rgb(255,0,255)
+  maroon = 0x800000,                   // rgb(128,0,0)
+  medium_aquamarine = 0x66CDAA,        // rgb(102,205,170)
+  medium_blue = 0x0000CD,              // rgb(0,0,205)
+  medium_orchid = 0xBA55D3,            // rgb(186,85,211)
+  medium_purple = 0x9370DB,            // rgb(147,112,219)
+  medium_sea_green = 0x3CB371,         // rgb(60,179,113)
+  medium_slate_blue = 0x7B68EE,        // rgb(123,104,238)
+  medium_spring_green = 0x00FA9A,      // rgb(0,250,154)
+  medium_turquoise = 0x48D1CC,         // rgb(72,209,204)
+  medium_violet_red = 0xC71585,        // rgb(199,21,133)
+  midnight_blue = 0x191970,            // rgb(25,25,112)
+  mint_cream = 0xF5FFFA,               // rgb(245,255,250)
+  misty_rose = 0xFFE4E1,               // rgb(255,228,225)
+  moccasin = 0xFFE4B5,                 // rgb(255,228,181)
+  navajo_white = 0xFFDEAD,             // rgb(255,222,173)
+  navy = 0x000080,                     // rgb(0,0,128)
+  old_lace = 0xFDF5E6,                 // rgb(253,245,230)
+  olive = 0x808000,                    // rgb(128,128,0)
+  olive_drab = 0x6B8E23,               // rgb(107,142,35)
+  orange = 0xFFA500,                   // rgb(255,165,0)
+  orange_red = 0xFF4500,               // rgb(255,69,0)
+  orchid = 0xDA70D6,                   // rgb(218,112,214)
+  pale_golden_rod = 0xEEE8AA,          // rgb(238,232,170)
+  pale_green = 0x98FB98,               // rgb(152,251,152)
+  pale_turquoise = 0xAFEEEE,           // rgb(175,238,238)
+  pale_violet_red = 0xDB7093,          // rgb(219,112,147)
+  papaya_whip = 0xFFEFD5,              // rgb(255,239,213)
+  peach_puff = 0xFFDAB9,               // rgb(255,218,185)
+  peru = 0xCD853F,                     // rgb(205,133,63)
+  pink = 0xFFC0CB,                     // rgb(255,192,203)
+  plum = 0xDDA0DD,                     // rgb(221,160,221)
+  powder_blue = 0xB0E0E6,              // rgb(176,224,230)
+  purple = 0x800080,                   // rgb(128,0,128)
+  rebecca_purple = 0x663399,           // rgb(102,51,153)
+  red = 0xFF0000,                      // rgb(255,0,0)
+  rosy_brown = 0xBC8F8F,               // rgb(188,143,143)
+  royal_blue = 0x4169E1,               // rgb(65,105,225)
+  saddle_brown = 0x8B4513,             // rgb(139,69,19)
+  salmon = 0xFA8072,                   // rgb(250,128,114)
+  sandy_brown = 0xF4A460,              // rgb(244,164,96)
+  sea_green = 0x2E8B57,                // rgb(46,139,87)
+  sea_shell = 0xFFF5EE,                // rgb(255,245,238)
+  sienna = 0xA0522D,                   // rgb(160,82,45)
+  silver = 0xC0C0C0,                   // rgb(192,192,192)
+  sky_blue = 0x87CEEB,                 // rgb(135,206,235)
+  slate_blue = 0x6A5ACD,               // rgb(106,90,205)
+  slate_gray = 0x708090,               // rgb(112,128,144)
+  snow = 0xFFFAFA,                     // rgb(255,250,250)
+  spring_green = 0x00FF7F,             // rgb(0,255,127)
+  steel_blue = 0x4682B4,               // rgb(70,130,180)
+  tan = 0xD2B48C,                      // rgb(210,180,140)
+  teal = 0x008080,                     // rgb(0,128,128)
+  thistle = 0xD8BFD8,                  // rgb(216,191,216)
+  tomato = 0xFF6347,                   // rgb(255,99,71)
+  turquoise = 0x40E0D0,                // rgb(64,224,208)
+  violet = 0xEE82EE,                   // rgb(238,130,238)
+  wheat = 0xF5DEB3,                    // rgb(245,222,179)
+  white = 0xFFFFFF,                    // rgb(255,255,255)
+  white_smoke = 0xF5F5F5,              // rgb(245,245,245)
+  yellow = 0xFFFF00,                   // rgb(255,255,0)
+  yellow_green = 0x9ACD32              // rgb(154,205,50)
+};                                     // enum class color
 
 enum class terminal_color : uint8_t {
   black = 30,
@@ -208,49 +173,46 @@ enum class terminal_color : uint8_t {
   bright_magenta,
   bright_cyan,
   bright_white
-};  // enum class terminal_color
+};
 
 enum class emphasis : uint8_t {
   bold = 1,
   italic = 1 << 1,
   underline = 1 << 2,
   strikethrough = 1 << 3
-};  // enum class emphasis
+};
 
 // rgb is a struct for red, green and blue colors.
-// We use rgb as name because some editors will show it as color direct in the
-// editor.
+// Using the name "rgb" makes some editors show the color in a tooltip.
 struct rgb {
-  FMT_CONSTEXPR_DECL rgb() : r(0), g(0), b(0) {}
-  FMT_CONSTEXPR_DECL rgb(uint8_t r_, uint8_t g_, uint8_t b_)
-    : r(r_), g(g_), b(b_) {}
-  FMT_CONSTEXPR_DECL rgb(uint32_t hex)
-    : r((hex >> 16) & 0xFF), g((hex >> 8) & 0xFF), b((hex) & 0xFF) {}
-  FMT_CONSTEXPR_DECL rgb(color hex)
-    : r((uint32_t(hex) >> 16) & 0xFF), g((uint32_t(hex) >> 8) & 0xFF),
-      b(uint32_t(hex) & 0xFF) {}
+  FMT_CONSTEXPR rgb() : r(0), g(0), b(0) {}
+  FMT_CONSTEXPR rgb(uint8_t r_, uint8_t g_, uint8_t b_) : r(r_), g(g_), b(b_) {}
+  FMT_CONSTEXPR rgb(uint32_t hex)
+      : r((hex >> 16) & 0xFF), g((hex >> 8) & 0xFF), b(hex & 0xFF) {}
+  FMT_CONSTEXPR rgb(color hex)
+      : r((uint32_t(hex) >> 16) & 0xFF),
+        g((uint32_t(hex) >> 8) & 0xFF),
+        b(uint32_t(hex) & 0xFF) {}
   uint8_t r;
   uint8_t g;
   uint8_t b;
 };
 
-namespace internal {
+namespace detail {
 
 // color is a struct of either a rgb color or a terminal color.
 struct color_type {
-  FMT_CONSTEXPR color_type() FMT_NOEXCEPT
-    : is_rgb(), value{} {}
-  FMT_CONSTEXPR color_type(color rgb_color) FMT_NOEXCEPT
-    : is_rgb(true), value{} {
+  FMT_CONSTEXPR color_type() FMT_NOEXCEPT : is_rgb(), value{} {}
+  FMT_CONSTEXPR color_type(color rgb_color) FMT_NOEXCEPT : is_rgb(true),
+                                                           value{} {
     value.rgb_color = static_cast<uint32_t>(rgb_color);
   }
-  FMT_CONSTEXPR color_type(rgb rgb_color) FMT_NOEXCEPT
-    : is_rgb(true), value{} {
-    value.rgb_color = (static_cast<uint32_t>(rgb_color.r) << 16)
-       | (static_cast<uint32_t>(rgb_color.g) << 8) | rgb_color.b;
+  FMT_CONSTEXPR color_type(rgb rgb_color) FMT_NOEXCEPT : is_rgb(true), value{} {
+    value.rgb_color = (static_cast<uint32_t>(rgb_color.r) << 16) |
+                      (static_cast<uint32_t>(rgb_color.g) << 8) | rgb_color.b;
   }
-  FMT_CONSTEXPR color_type(terminal_color term_color) FMT_NOEXCEPT
-    : is_rgb(), value{} {
+  FMT_CONSTEXPR color_type(terminal_color term_color) FMT_NOEXCEPT : is_rgb(),
+                                                                     value{} {
     value.term_color = static_cast<uint8_t>(term_color);
   }
   bool is_rgb;
@@ -259,21 +221,23 @@ struct color_type {
     uint32_t rgb_color;
   } value;
 };
-} // namespace internal
+}  // namespace detail
 
 // Experimental text formatting support.
 class text_style {
  public:
   FMT_CONSTEXPR text_style(emphasis em = emphasis()) FMT_NOEXCEPT
-      : set_foreground_color(), set_background_color(), ems(em) {}
+      : set_foreground_color(),
+        set_background_color(),
+        ems(em) {}
 
-  FMT_CONSTEXPR text_style &operator|=(const text_style &rhs) {
+  FMT_CONSTEXPR text_style& operator|=(const text_style& rhs) {
     if (!set_foreground_color) {
       set_foreground_color = rhs.set_foreground_color;
       foreground_color = rhs.foreground_color;
     } else if (rhs.set_foreground_color) {
       if (!foreground_color.is_rgb || !rhs.foreground_color.is_rgb)
-        throw format_error("can't OR a terminal color");
+        FMT_THROW(format_error("can't OR a terminal color"));
       foreground_color.value.rgb_color |= rhs.foreground_color.value.rgb_color;
     }
 
@@ -282,7 +246,7 @@ class text_style {
       background_color = rhs.background_color;
     } else if (rhs.set_background_color) {
       if (!background_color.is_rgb || !rhs.background_color.is_rgb)
-        throw format_error("can't OR a terminal color");
+        FMT_THROW(format_error("can't OR a terminal color"));
       background_color.value.rgb_color |= rhs.background_color.value.rgb_color;
     }
 
@@ -291,18 +255,18 @@ class text_style {
     return *this;
   }
 
-  friend FMT_CONSTEXPR
-  text_style operator|(text_style lhs, const text_style &rhs) {
+  friend FMT_CONSTEXPR text_style operator|(text_style lhs,
+                                            const text_style& rhs) {
     return lhs |= rhs;
   }
 
-  FMT_CONSTEXPR text_style &operator&=(const text_style &rhs) {
+  FMT_CONSTEXPR text_style& operator&=(const text_style& rhs) {
     if (!set_foreground_color) {
       set_foreground_color = rhs.set_foreground_color;
       foreground_color = rhs.foreground_color;
     } else if (rhs.set_foreground_color) {
       if (!foreground_color.is_rgb || !rhs.foreground_color.is_rgb)
-        throw format_error("can't AND a terminal color");
+        FMT_THROW(format_error("can't AND a terminal color"));
       foreground_color.value.rgb_color &= rhs.foreground_color.value.rgb_color;
     }
 
@@ -311,7 +275,7 @@ class text_style {
       background_color = rhs.background_color;
     } else if (rhs.set_background_color) {
       if (!background_color.is_rgb || !rhs.background_color.is_rgb)
-        throw format_error("can't AND a terminal color");
+        FMT_THROW(format_error("can't AND a terminal color"));
       background_color.value.rgb_color &= rhs.background_color.value.rgb_color;
     }
 
@@ -320,8 +284,8 @@ class text_style {
     return *this;
   }
 
-  friend FMT_CONSTEXPR
-  text_style operator&(text_style lhs, const text_style &rhs) {
+  friend FMT_CONSTEXPR text_style operator&(text_style lhs,
+                                            const text_style& rhs) {
     return lhs &= rhs;
   }
 
@@ -334,51 +298,51 @@ class text_style {
   FMT_CONSTEXPR bool has_emphasis() const FMT_NOEXCEPT {
     return static_cast<uint8_t>(ems) != 0;
   }
-  FMT_CONSTEXPR internal::color_type get_foreground() const FMT_NOEXCEPT {
-    assert(has_foreground() && "no foreground specified for this style");
+  FMT_CONSTEXPR detail::color_type get_foreground() const FMT_NOEXCEPT {
+    FMT_ASSERT(has_foreground(), "no foreground specified for this style");
     return foreground_color;
   }
-  FMT_CONSTEXPR internal::color_type get_background() const FMT_NOEXCEPT {
-    assert(has_background() && "no background specified for this style");
+  FMT_CONSTEXPR detail::color_type get_background() const FMT_NOEXCEPT {
+    FMT_ASSERT(has_background(), "no background specified for this style");
     return background_color;
   }
   FMT_CONSTEXPR emphasis get_emphasis() const FMT_NOEXCEPT {
-    assert(has_emphasis() && "no emphasis specified for this style");
+    FMT_ASSERT(has_emphasis(), "no emphasis specified for this style");
     return ems;
   }
 
-private:
- FMT_CONSTEXPR text_style(bool is_foreground,
-                          internal::color_type text_color) FMT_NOEXCEPT
-     : set_foreground_color(),
-       set_background_color(),
-       ems() {
-   if (is_foreground) {
-     foreground_color = text_color;
-     set_foreground_color = true;
-   } else {
-     background_color = text_color;
-     set_background_color = true;
-   }
- }
+ private:
+  FMT_CONSTEXPR text_style(bool is_foreground,
+                           detail::color_type text_color) FMT_NOEXCEPT
+      : set_foreground_color(),
+        set_background_color(),
+        ems() {
+    if (is_foreground) {
+      foreground_color = text_color;
+      set_foreground_color = true;
+    } else {
+      background_color = text_color;
+      set_background_color = true;
+    }
+  }
 
-  friend FMT_CONSTEXPR_DECL text_style fg(internal::color_type foreground)
+  friend FMT_CONSTEXPR_DECL text_style fg(detail::color_type foreground)
       FMT_NOEXCEPT;
-  friend FMT_CONSTEXPR_DECL text_style bg(internal::color_type background)
+  friend FMT_CONSTEXPR_DECL text_style bg(detail::color_type background)
       FMT_NOEXCEPT;
 
-  internal::color_type foreground_color;
-  internal::color_type background_color;
+  detail::color_type foreground_color;
+  detail::color_type background_color;
   bool set_foreground_color;
   bool set_background_color;
   emphasis ems;
 };
 
-FMT_CONSTEXPR text_style fg(internal::color_type foreground) FMT_NOEXCEPT {
+FMT_CONSTEXPR text_style fg(detail::color_type foreground) FMT_NOEXCEPT {
   return text_style(/*is_foreground=*/true, foreground);
 }
 
-FMT_CONSTEXPR text_style bg(internal::color_type background) FMT_NOEXCEPT {
+FMT_CONSTEXPR text_style bg(detail::color_type background) FMT_NOEXCEPT {
   return text_style(/*is_foreground=*/false, background);
 }
 
@@ -386,23 +350,21 @@ FMT_CONSTEXPR text_style operator|(emphasis lhs, emphasis rhs) FMT_NOEXCEPT {
   return text_style(lhs) | rhs;
 }
 
-namespace internal {
+namespace detail {
 
-template <typename Char>
-struct ansi_color_escape {
-  FMT_CONSTEXPR ansi_color_escape(internal::color_type text_color,
-                                  const char * esc) FMT_NOEXCEPT {
+template <typename Char> struct ansi_color_escape {
+  FMT_CONSTEXPR ansi_color_escape(detail::color_type text_color,
+                                  const char* esc) FMT_NOEXCEPT {
     // If we have a terminal color, we need to output another escape code
     // sequence.
     if (!text_color.is_rgb) {
-      bool is_background = esc == internal::data::BACKGROUND_COLOR;
+      bool is_background = esc == detail::data::background_color;
       uint32_t value = text_color.value.term_color;
       // Background ASCII codes are the same as the foreground ones but with
       // 10 more.
-      if (is_background)
-        value += 10u;
+      if (is_background) value += 10u;
 
-      std::size_t index = 0;
+      size_t index = 0;
       buffer[index++] = static_cast<Char>('\x1b');
       buffer[index++] = static_cast<Char>('[');
 
@@ -422,7 +384,7 @@ struct ansi_color_escape {
       buffer[i] = static_cast<Char>(esc[i]);
     }
     rgb color(text_color.value.rgb_color);
-    to_esc(color.r, buffer +  7, ';');
+    to_esc(color.r, buffer + 7, ';');
     to_esc(color.g, buffer + 11, ';');
     to_esc(color.b, buffer + 15, 'm');
     buffer[19] = static_cast<Char>(0);
@@ -430,19 +392,15 @@ struct ansi_color_escape {
   FMT_CONSTEXPR ansi_color_escape(emphasis em) FMT_NOEXCEPT {
     uint8_t em_codes[4] = {};
     uint8_t em_bits = static_cast<uint8_t>(em);
-    if (em_bits & static_cast<uint8_t>(emphasis::bold))
-      em_codes[0] = 1;
-    if (em_bits & static_cast<uint8_t>(emphasis::italic))
-      em_codes[1] = 3;
-    if (em_bits & static_cast<uint8_t>(emphasis::underline))
-      em_codes[2] = 4;
+    if (em_bits & static_cast<uint8_t>(emphasis::bold)) em_codes[0] = 1;
+    if (em_bits & static_cast<uint8_t>(emphasis::italic)) em_codes[1] = 3;
+    if (em_bits & static_cast<uint8_t>(emphasis::underline)) em_codes[2] = 4;
     if (em_bits & static_cast<uint8_t>(emphasis::strikethrough))
       em_codes[3] = 9;
 
-    std::size_t index = 0;
+    size_t index = 0;
     for (int i = 0; i < 4; ++i) {
-      if (!em_codes[i])
-        continue;
+      if (!em_codes[i]) continue;
       buffer[index++] = static_cast<Char>('\x1b');
       buffer[index++] = static_cast<Char>('[');
       buffer[index++] = static_cast<Char>('0' + em_codes[i]);
@@ -450,12 +408,17 @@ struct ansi_color_escape {
     }
     buffer[index++] = static_cast<Char>(0);
   }
-  FMT_CONSTEXPR operator const Char *() const FMT_NOEXCEPT { return buffer; }
+  FMT_CONSTEXPR operator const Char*() const FMT_NOEXCEPT { return buffer; }
 
-private:
+  FMT_CONSTEXPR const Char* begin() const FMT_NOEXCEPT { return buffer; }
+  FMT_CONSTEXPR const Char* end() const FMT_NOEXCEPT {
+    return buffer + std::char_traits<Char>::length(buffer);
+  }
+
+ private:
   Char buffer[7u + 3u * 4u + 1u];
 
-  static FMT_CONSTEXPR void to_esc(uint8_t c, Char *out,
+  static FMT_CONSTEXPR void to_esc(uint8_t c, Char* out,
                                    char delimiter) FMT_NOEXCEPT {
     out[0] = static_cast<Char>('0' + c / 100);
     out[1] = static_cast<Char>('0' + c / 10 % 10);
@@ -465,95 +428,98 @@ private:
 };
 
 template <typename Char>
-FMT_CONSTEXPR ansi_color_escape<Char>
-make_foreground_color(internal::color_type foreground) FMT_NOEXCEPT {
-  return ansi_color_escape<Char>(foreground, internal::data::FOREGROUND_COLOR);
+FMT_CONSTEXPR ansi_color_escape<Char> make_foreground_color(
+    detail::color_type foreground) FMT_NOEXCEPT {
+  return ansi_color_escape<Char>(foreground, detail::data::foreground_color);
 }
 
 template <typename Char>
-FMT_CONSTEXPR ansi_color_escape<Char>
-make_background_color(internal::color_type background) FMT_NOEXCEPT {
-  return ansi_color_escape<Char>(background, internal::data::BACKGROUND_COLOR);
+FMT_CONSTEXPR ansi_color_escape<Char> make_background_color(
+    detail::color_type background) FMT_NOEXCEPT {
+  return ansi_color_escape<Char>(background, detail::data::background_color);
 }
 
 template <typename Char>
-FMT_CONSTEXPR ansi_color_escape<Char>
-make_emphasis(emphasis em) FMT_NOEXCEPT {
+FMT_CONSTEXPR ansi_color_escape<Char> make_emphasis(emphasis em) FMT_NOEXCEPT {
   return ansi_color_escape<Char>(em);
 }
 
 template <typename Char>
-inline void fputs(const Char *chars, FILE *stream) FMT_NOEXCEPT {
+inline void fputs(const Char* chars, FILE* stream) FMT_NOEXCEPT {
   std::fputs(chars, stream);
 }
 
 template <>
-inline void fputs<wchar_t>(const wchar_t *chars, FILE *stream) FMT_NOEXCEPT {
+inline void fputs<wchar_t>(const wchar_t* chars, FILE* stream) FMT_NOEXCEPT {
   std::fputws(chars, stream);
 }
 
+template <typename Char> inline void reset_color(FILE* stream) FMT_NOEXCEPT {
+  fputs(detail::data::reset_color, stream);
+}
+
+template <> inline void reset_color<wchar_t>(FILE* stream) FMT_NOEXCEPT {
+  fputs(detail::data::wreset_color, stream);
+}
+
 template <typename Char>
-inline void reset_color(FILE *stream) FMT_NOEXCEPT {
-  fputs(internal::data::RESET_COLOR, stream);
+inline void reset_color(buffer<Char>& buffer) FMT_NOEXCEPT {
+  const char* begin = data::reset_color;
+  const char* end = begin + sizeof(data::reset_color) - 1;
+  buffer.append(begin, end);
 }
 
-template <>
-inline void reset_color<wchar_t>(FILE *stream) FMT_NOEXCEPT {
-  fputs(internal::data::WRESET_COLOR, stream);
-}
-
-// The following specialiazation disables using std::FILE as a character type,
-// which is needed because or else
-//   fmt::print(stderr, fmt::emphasis::bold, "");
-// would take stderr (a std::FILE *) as the format string.
-template <>
-struct is_string<std::FILE *> : std::false_type {};
-template <>
-struct is_string<const std::FILE *> : std::false_type {};
-} // namespace internal
-
-template <
-  typename S, typename Char = typename internal::char_t<S>::type>
-void vprint(std::FILE *f, const text_style &ts, const S &format,
-            basic_format_args<typename buffer_context<Char>::type> args) {
+template <typename Char>
+void vformat_to(buffer<Char>& buf, const text_style& ts,
+                basic_string_view<Char> format_str,
+                basic_format_args<buffer_context<type_identity_t<Char>>> args) {
   bool has_style = false;
   if (ts.has_emphasis()) {
     has_style = true;
-    internal::fputs<Char>(
-          internal::make_emphasis<Char>(ts.get_emphasis()), f);
+    auto emphasis = detail::make_emphasis<Char>(ts.get_emphasis());
+    buf.append(emphasis.begin(), emphasis.end());
   }
   if (ts.has_foreground()) {
     has_style = true;
-    internal::fputs<Char>(
-          internal::make_foreground_color<Char>(ts.get_foreground()), f);
+    auto foreground = detail::make_foreground_color<Char>(ts.get_foreground());
+    buf.append(foreground.begin(), foreground.end());
   }
   if (ts.has_background()) {
     has_style = true;
-    internal::fputs<Char>(
-        internal::make_background_color<Char>(ts.get_background()), f);
-  }
-  vprint(f, format, args);
-  if (has_style) {
-    internal::reset_color<Char>(f);
+    auto background = detail::make_background_color<Char>(ts.get_background());
+    buf.append(background.begin(), background.end());
   }
+  detail::vformat_to(buf, format_str, args);
+  if (has_style) detail::reset_color<Char>(buf);
+}
+}  // namespace detail
+
+template <typename S, typename Char = char_t<S>>
+void vprint(std::FILE* f, const text_style& ts, const S& format,
+            basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  basic_memory_buffer<Char> buf;
+  detail::vformat_to(buf, ts, to_string_view(format), args);
+  buf.push_back(Char(0));
+  detail::fputs(buf.data(), f);
 }
 
 /**
+  \rst
   Formats a string and prints it to the specified file stream using ANSI
   escape sequences to specify text formatting.
-  Example:
+
+  **Example**::
+
     fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
                "Elapsed time: {0:.2f} seconds", 1.23);
+  \endrst
  */
-template <typename String, typename... Args>
-typename std::enable_if<internal::is_string<String>::value>::type print(
-    std::FILE *f, const text_style &ts, const String &format_str,
-    const Args &... args) {
-  internal::check_format_string<Args...>(format_str);
-  typedef typename internal::char_t<String>::type char_t;
-  typedef typename buffer_context<char_t>::type context_t;
-  format_arg_store<context_t, Args...> as{args...};
-  vprint(f, ts, format_str, basic_format_args<context_t>(as));
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_string<S>::value)>
+void print(std::FILE* f, const text_style& ts, const S& format_str,
+           const Args&... args) {
+  vprint(f, ts, format_str,
+         fmt::make_args_checked<Args...>(format_str, args...));
 }
 
 /**
@@ -563,14 +529,74 @@ typename std::enable_if<internal::is_string<String>::value>::type print(
     fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
                "Elapsed time: {0:.2f} seconds", 1.23);
  */
-template <typename String, typename... Args>
-typename std::enable_if<internal::is_string<String>::value>::type print(
-    const text_style &ts, const String &format_str,
-    const Args &... args) {
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_string<S>::value)>
+void print(const text_style& ts, const S& format_str, const Args&... args) {
   return print(stdout, ts, format_str, args...);
 }
 
-#endif
+template <typename S, typename Char = char_t<S>>
+inline std::basic_string<Char> vformat(
+    const text_style& ts, const S& format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  basic_memory_buffer<Char> buf;
+  detail::vformat_to(buf, ts, to_string_view(format_str), args);
+  return fmt::to_string(buf);
+}
+
+/**
+  \rst
+  Formats arguments and returns the result as a string using ANSI
+  escape sequences to specify text formatting.
+
+  **Example**::
+
+    #include <fmt/color.h>
+    std::string message = fmt::format(fmt::emphasis::bold | fg(fmt::color::red),
+                                      "The answer is {}", 42);
+  \endrst
+*/
+template <typename S, typename... Args, typename Char = char_t<S>>
+inline std::basic_string<Char> format(const text_style& ts, const S& format_str,
+                                      const Args&... args) {
+  return vformat(ts, to_string_view(format_str),
+                 fmt::make_args_checked<Args...>(format_str, args...));
+}
+
+/**
+  Formats a string with the given text_style and writes the output to ``out``.
+ */
+template <typename OutputIt, typename Char,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value)>
+OutputIt vformat_to(
+    OutputIt out, const text_style& ts, basic_string_view<Char> format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  decltype(detail::get_buffer<Char>(out)) buf(detail::get_buffer_init(out));
+  detail::vformat_to(buf, ts, format_str, args);
+  return detail::get_iterator(buf);
+}
+
+/**
+  \rst
+  Formats arguments with the given text_style, writes the result to the output
+  iterator ``out`` and returns the iterator past the end of the output range.
+
+  **Example**::
+
+    std::vector<char> out;
+    fmt::format_to(std::back_inserter(out),
+                   fmt::emphasis::bold | fg(fmt::color::red), "{}", 42);
+  \endrst
+*/
+template <typename OutputIt, typename S, typename... Args,
+          bool enable = detail::is_output_iterator<OutputIt, char_t<S>>::value&&
+              detail::is_string<S>::value>
+inline auto format_to(OutputIt out, const text_style& ts, const S& format_str,
+                      Args&&... args) ->
+    typename std::enable_if<enable, OutputIt>::type {
+  return vformat_to(out, ts, to_string_view(format_str),
+                    fmt::make_args_checked<Args...>(format_str, args...));
+}
 
 FMT_END_NAMESPACE
 

include/fmt/compile.h

@@ -0,0 +1,701 @@
+// Formatting library for C++ - experimental format string compilation
+//
+// Copyright (c) 2012 - present, Victor Zverovich and fmt contributors
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_COMPILE_H_
+#define FMT_COMPILE_H_
+
+#include <vector>
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+// A compile-time string which is compiled into fast formatting code.
+class compiled_string {};
+
+template <typename S>
+struct is_compiled_string : std::is_base_of<compiled_string, S> {};
+
+/**
+  \rst
+  Converts a string literal *s* into a format string that will be parsed at
+  compile time and converted into efficient formatting code. Requires C++17
+  ``constexpr if`` compiler support.
+
+  **Example**::
+
+    // Converts 42 into std::string using the most efficient method and no
+    // runtime format string processing.
+    std::string s = fmt::format(FMT_COMPILE("{}"), 42);
+  \endrst
+ */
+#define FMT_COMPILE(s) FMT_STRING_IMPL(s, fmt::detail::compiled_string)
+
+template <typename T, typename... Tail>
+const T& first(const T& value, const Tail&...) {
+  return value;
+}
+
+// Part of a compiled format string. It can be either literal text or a
+// replacement field.
+template <typename Char> struct format_part {
+  enum class kind { arg_index, arg_name, text, replacement };
+
+  struct replacement {
+    arg_ref<Char> arg_id;
+    dynamic_format_specs<Char> specs;
+  };
+
+  kind part_kind;
+  union value {
+    int arg_index;
+    basic_string_view<Char> str;
+    replacement repl;
+
+    FMT_CONSTEXPR value(int index = 0) : arg_index(index) {}
+    FMT_CONSTEXPR value(basic_string_view<Char> s) : str(s) {}
+    FMT_CONSTEXPR value(replacement r) : repl(r) {}
+  } val;
+  // Position past the end of the argument id.
+  const Char* arg_id_end = nullptr;
+
+  FMT_CONSTEXPR format_part(kind k = kind::arg_index, value v = {})
+      : part_kind(k), val(v) {}
+
+  static FMT_CONSTEXPR format_part make_arg_index(int index) {
+    return format_part(kind::arg_index, index);
+  }
+  static FMT_CONSTEXPR format_part make_arg_name(basic_string_view<Char> name) {
+    return format_part(kind::arg_name, name);
+  }
+  static FMT_CONSTEXPR format_part make_text(basic_string_view<Char> text) {
+    return format_part(kind::text, text);
+  }
+  static FMT_CONSTEXPR format_part make_replacement(replacement repl) {
+    return format_part(kind::replacement, repl);
+  }
+};
+
+template <typename Char> struct part_counter {
+  unsigned num_parts = 0;
+
+  FMT_CONSTEXPR void on_text(const Char* begin, const Char* end) {
+    if (begin != end) ++num_parts;
+  }
+
+  FMT_CONSTEXPR int on_arg_id() { return ++num_parts, 0; }
+  FMT_CONSTEXPR int on_arg_id(int) { return ++num_parts, 0; }
+  FMT_CONSTEXPR int on_arg_id(basic_string_view<Char>) {
+    return ++num_parts, 0;
+  }
+
+  FMT_CONSTEXPR void on_replacement_field(int, const Char*) {}
+
+  FMT_CONSTEXPR const Char* on_format_specs(int, const Char* begin,
+                                            const Char* end) {
+    // Find the matching brace.
+    unsigned brace_counter = 0;
+    for (; begin != end; ++begin) {
+      if (*begin == '{') {
+        ++brace_counter;
+      } else if (*begin == '}') {
+        if (brace_counter == 0u) break;
+        --brace_counter;
+      }
+    }
+    return begin;
+  }
+
+  FMT_CONSTEXPR void on_error(const char*) {}
+};
+
+// Counts the number of parts in a format string.
+template <typename Char>
+FMT_CONSTEXPR unsigned count_parts(basic_string_view<Char> format_str) {
+  part_counter<Char> counter;
+  parse_format_string<true>(format_str, counter);
+  return counter.num_parts;
+}
+
+template <typename Char, typename PartHandler>
+class format_string_compiler : public error_handler {
+ private:
+  using part = format_part<Char>;
+
+  PartHandler handler_;
+  part part_;
+  basic_string_view<Char> format_str_;
+  basic_format_parse_context<Char> parse_context_;
+
+ public:
+  FMT_CONSTEXPR format_string_compiler(basic_string_view<Char> format_str,
+                                       PartHandler handler)
+      : handler_(handler),
+        format_str_(format_str),
+        parse_context_(format_str) {}
+
+  FMT_CONSTEXPR void on_text(const Char* begin, const Char* end) {
+    if (begin != end)
+      handler_(part::make_text({begin, to_unsigned(end - begin)}));
+  }
+
+  FMT_CONSTEXPR int on_arg_id() {
+    part_ = part::make_arg_index(parse_context_.next_arg_id());
+    return 0;
+  }
+
+  FMT_CONSTEXPR int on_arg_id(int id) {
+    parse_context_.check_arg_id(id);
+    part_ = part::make_arg_index(id);
+    return 0;
+  }
+
+  FMT_CONSTEXPR int on_arg_id(basic_string_view<Char> id) {
+    part_ = part::make_arg_name(id);
+    return 0;
+  }
+
+  FMT_CONSTEXPR void on_replacement_field(int, const Char* ptr) {
+    part_.arg_id_end = ptr;
+    handler_(part_);
+  }
+
+  FMT_CONSTEXPR const Char* on_format_specs(int, const Char* begin,
+                                            const Char* end) {
+    auto repl = typename part::replacement();
+    dynamic_specs_handler<basic_format_parse_context<Char>> handler(
+        repl.specs, parse_context_);
+    auto it = parse_format_specs(begin, end, handler);
+    if (*it != '}') on_error("missing '}' in format string");
+    repl.arg_id = part_.part_kind == part::kind::arg_index
+                      ? arg_ref<Char>(part_.val.arg_index)
+                      : arg_ref<Char>(part_.val.str);
+    auto part = part::make_replacement(repl);
+    part.arg_id_end = begin;
+    handler_(part);
+    return it;
+  }
+};
+
+// Compiles a format string and invokes handler(part) for each parsed part.
+template <bool IS_CONSTEXPR, typename Char, typename PartHandler>
+FMT_CONSTEXPR void compile_format_string(basic_string_view<Char> format_str,
+                                         PartHandler handler) {
+  parse_format_string<IS_CONSTEXPR>(
+      format_str,
+      format_string_compiler<Char, PartHandler>(format_str, handler));
+}
+
+template <typename OutputIt, typename Context, typename Id>
+void format_arg(
+    basic_format_parse_context<typename Context::char_type>& parse_ctx,
+    Context& ctx, Id arg_id) {
+  ctx.advance_to(visit_format_arg(
+      arg_formatter<OutputIt, typename Context::char_type>(ctx, &parse_ctx),
+      ctx.arg(arg_id)));
+}
+
+// vformat_to is defined in a subnamespace to prevent ADL.
+namespace cf {
+template <typename Context, typename OutputIt, typename CompiledFormat>
+auto vformat_to(OutputIt out, CompiledFormat& cf,
+                basic_format_args<Context> args) -> typename Context::iterator {
+  using char_type = typename Context::char_type;
+  basic_format_parse_context<char_type> parse_ctx(
+      to_string_view(cf.format_str_));
+  Context ctx(out, args);
+
+  const auto& parts = cf.parts();
+  for (auto part_it = std::begin(parts); part_it != std::end(parts);
+       ++part_it) {
+    const auto& part = *part_it;
+    const auto& value = part.val;
+
+    using format_part_t = format_part<char_type>;
+    switch (part.part_kind) {
+    case format_part_t::kind::text: {
+      const auto text = value.str;
+      auto output = ctx.out();
+      auto&& it = reserve(output, text.size());
+      it = std::copy_n(text.begin(), text.size(), it);
+      ctx.advance_to(output);
+      break;
+    }
+
+    case format_part_t::kind::arg_index:
+      advance_to(parse_ctx, part.arg_id_end);
+      detail::format_arg<OutputIt>(parse_ctx, ctx, value.arg_index);
+      break;
+
+    case format_part_t::kind::arg_name:
+      advance_to(parse_ctx, part.arg_id_end);
+      detail::format_arg<OutputIt>(parse_ctx, ctx, value.str);
+      break;
+
+    case format_part_t::kind::replacement: {
+      const auto& arg_id_value = value.repl.arg_id.val;
+      const auto arg = value.repl.arg_id.kind == arg_id_kind::index
+                           ? ctx.arg(arg_id_value.index)
+                           : ctx.arg(arg_id_value.name);
+
+      auto specs = value.repl.specs;
+
+      handle_dynamic_spec<width_checker>(specs.width, specs.width_ref, ctx);
+      handle_dynamic_spec<precision_checker>(specs.precision,
+                                             specs.precision_ref, ctx);
+
+      error_handler h;
+      numeric_specs_checker<error_handler> checker(h, arg.type());
+      if (specs.align == align::numeric) checker.require_numeric_argument();
+      if (specs.sign != sign::none) checker.check_sign();
+      if (specs.alt) checker.require_numeric_argument();
+      if (specs.precision >= 0) checker.check_precision();
+
+      advance_to(parse_ctx, part.arg_id_end);
+      ctx.advance_to(
+          visit_format_arg(arg_formatter<OutputIt, typename Context::char_type>(
+                               ctx, nullptr, &specs),
+                           arg));
+      break;
+    }
+    }
+  }
+  return ctx.out();
+}
+}  // namespace cf
+
+struct basic_compiled_format {};
+
+template <typename S, typename = void>
+struct compiled_format_base : basic_compiled_format {
+  using char_type = char_t<S>;
+  using parts_container = std::vector<detail::format_part<char_type>>;
+
+  parts_container compiled_parts;
+
+  explicit compiled_format_base(basic_string_view<char_type> format_str) {
+    compile_format_string<false>(format_str,
+                                 [this](const format_part<char_type>& part) {
+                                   compiled_parts.push_back(part);
+                                 });
+  }
+
+  const parts_container& parts() const { return compiled_parts; }
+};
+
+template <typename Char, unsigned N> struct format_part_array {
+  format_part<Char> data[N] = {};
+  FMT_CONSTEXPR format_part_array() = default;
+};
+
+template <typename Char, unsigned N>
+FMT_CONSTEXPR format_part_array<Char, N> compile_to_parts(
+    basic_string_view<Char> format_str) {
+  format_part_array<Char, N> parts;
+  unsigned counter = 0;
+  // This is not a lambda for compatibility with older compilers.
+  struct {
+    format_part<Char>* parts;
+    unsigned* counter;
+    FMT_CONSTEXPR void operator()(const format_part<Char>& part) {
+      parts[(*counter)++] = part;
+    }
+  } collector{parts.data, &counter};
+  compile_format_string<true>(format_str, collector);
+  if (counter < N) {
+    parts.data[counter] =
+        format_part<Char>::make_text(basic_string_view<Char>());
+  }
+  return parts;
+}
+
+template <typename T> constexpr const T& constexpr_max(const T& a, const T& b) {
+  return (a < b) ? b : a;
+}
+
+template <typename S>
+struct compiled_format_base<S, enable_if_t<is_compile_string<S>::value>>
+    : basic_compiled_format {
+  using char_type = char_t<S>;
+
+  FMT_CONSTEXPR explicit compiled_format_base(basic_string_view<char_type>) {}
+
+// Workaround for old compilers. Format string compilation will not be
+// performed there anyway.
+#if FMT_USE_CONSTEXPR
+  static FMT_CONSTEXPR_DECL const unsigned num_format_parts =
+      constexpr_max(count_parts(to_string_view(S())), 1u);
+#else
+  static const unsigned num_format_parts = 1;
+#endif
+
+  using parts_container = format_part<char_type>[num_format_parts];
+
+  const parts_container& parts() const {
+    static FMT_CONSTEXPR_DECL const auto compiled_parts =
+        compile_to_parts<char_type, num_format_parts>(
+            detail::to_string_view(S()));
+    return compiled_parts.data;
+  }
+};
+
+template <typename S, typename... Args>
+class compiled_format : private compiled_format_base<S> {
+ public:
+  using typename compiled_format_base<S>::char_type;
+
+ private:
+  basic_string_view<char_type> format_str_;
+
+  template <typename Context, typename OutputIt, typename CompiledFormat>
+  friend auto cf::vformat_to(OutputIt out, CompiledFormat& cf,
+                             basic_format_args<Context> args) ->
+      typename Context::iterator;
+
+ public:
+  compiled_format() = delete;
+  explicit constexpr compiled_format(basic_string_view<char_type> format_str)
+      : compiled_format_base<S>(format_str), format_str_(format_str) {}
+};
+
+#ifdef __cpp_if_constexpr
+template <typename... Args> struct type_list {};
+
+// Returns a reference to the argument at index N from [first, rest...].
+template <int N, typename T, typename... Args>
+constexpr const auto& get([[maybe_unused]] const T& first,
+                          [[maybe_unused]] const Args&... rest) {
+  static_assert(N < 1 + sizeof...(Args), "index is out of bounds");
+  if constexpr (N == 0)
+    return first;
+  else
+    return get<N - 1>(rest...);
+}
+
+template <int N, typename> struct get_type_impl;
+
+template <int N, typename... Args> struct get_type_impl<N, type_list<Args...>> {
+  using type = remove_cvref_t<decltype(get<N>(std::declval<Args>()...))>;
+};
+
+template <int N, typename T>
+using get_type = typename get_type_impl<N, T>::type;
+
+template <typename T> struct is_compiled_format : std::false_type {};
+
+template <typename Char> struct text {
+  basic_string_view<Char> data;
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  OutputIt format(OutputIt out, const Args&...) const {
+    return write<Char>(out, data);
+  }
+};
+
+template <typename Char>
+struct is_compiled_format<text<Char>> : std::true_type {};
+
+template <typename Char>
+constexpr text<Char> make_text(basic_string_view<Char> s, size_t pos,
+                               size_t size) {
+  return {{&s[pos], size}};
+}
+
+template <typename Char> struct code_unit {
+  Char value;
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  OutputIt format(OutputIt out, const Args&...) const {
+    return write<Char>(out, value);
+  }
+};
+
+template <typename Char>
+struct is_compiled_format<code_unit<Char>> : std::true_type {};
+
+// A replacement field that refers to argument N.
+template <typename Char, typename T, int N> struct field {
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  OutputIt format(OutputIt out, const Args&... args) const {
+    // This ensures that the argument type is convertile to `const T&`.
+    const T& arg = get<N>(args...);
+    return write<Char>(out, arg);
+  }
+};
+
+template <typename Char, typename T, int N>
+struct is_compiled_format<field<Char, T, N>> : std::true_type {};
+
+// A replacement field that refers to argument N and has format specifiers.
+template <typename Char, typename T, int N> struct spec_field {
+  using char_type = Char;
+  mutable formatter<T, Char> fmt;
+
+  template <typename OutputIt, typename... Args>
+  OutputIt format(OutputIt out, const Args&... args) const {
+    // This ensures that the argument type is convertile to `const T&`.
+    const T& arg = get<N>(args...);
+    const auto& vargs =
+        make_format_args<basic_format_context<OutputIt, Char>>(args...);
+    basic_format_context<OutputIt, Char> ctx(out, vargs);
+    return fmt.format(arg, ctx);
+  }
+};
+
+template <typename Char, typename T, int N>
+struct is_compiled_format<spec_field<Char, T, N>> : std::true_type {};
+
+template <typename L, typename R> struct concat {
+  L lhs;
+  R rhs;
+  using char_type = typename L::char_type;
+
+  template <typename OutputIt, typename... Args>
+  OutputIt format(OutputIt out, const Args&... args) const {
+    out = lhs.format(out, args...);
+    return rhs.format(out, args...);
+  }
+};
+
+template <typename L, typename R>
+struct is_compiled_format<concat<L, R>> : std::true_type {};
+
+template <typename L, typename R>
+constexpr concat<L, R> make_concat(L lhs, R rhs) {
+  return {lhs, rhs};
+}
+
+struct unknown_format {};
+
+template <typename Char>
+constexpr size_t parse_text(basic_string_view<Char> str, size_t pos) {
+  for (size_t size = str.size(); pos != size; ++pos) {
+    if (str[pos] == '{' || str[pos] == '}') break;
+  }
+  return pos;
+}
+
+template <typename Args, size_t POS, int ID, typename S>
+constexpr auto compile_format_string(S format_str);
+
+template <typename Args, size_t POS, int ID, typename T, typename S>
+constexpr auto parse_tail(T head, S format_str) {
+  if constexpr (POS !=
+                basic_string_view<typename S::char_type>(format_str).size()) {
+    constexpr auto tail = compile_format_string<Args, POS, ID>(format_str);
+    if constexpr (std::is_same<remove_cvref_t<decltype(tail)>,
+                               unknown_format>())
+      return tail;
+    else
+      return make_concat(head, tail);
+  } else {
+    return head;
+  }
+}
+
+template <typename T, typename Char> struct parse_specs_result {
+  formatter<T, Char> fmt;
+  size_t end;
+  int next_arg_id;
+};
+
+template <typename T, typename Char>
+constexpr parse_specs_result<T, Char> parse_specs(basic_string_view<Char> str,
+                                                  size_t pos, int arg_id) {
+  str.remove_prefix(pos);
+  auto ctx = basic_format_parse_context<Char>(str, {}, arg_id + 1);
+  auto f = formatter<T, Char>();
+  auto end = f.parse(ctx);
+  return {f, pos + (end - str.data()) + 1, ctx.next_arg_id()};
+}
+
+// Compiles a non-empty format string and returns the compiled representation
+// or unknown_format() on unrecognized input.
+template <typename Args, size_t POS, int ID, typename S>
+constexpr auto compile_format_string(S format_str) {
+  using char_type = typename S::char_type;
+  constexpr basic_string_view<char_type> str = format_str;
+  if constexpr (str[POS] == '{') {
+    if (POS + 1 == str.size())
+      throw format_error("unmatched '{' in format string");
+    if constexpr (str[POS + 1] == '{') {
+      return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), format_str);
+    } else if constexpr (str[POS + 1] == '}') {
+      using type = get_type<ID, Args>;
+      return parse_tail<Args, POS + 2, ID + 1>(field<char_type, type, ID>(),
+                                               format_str);
+    } else if constexpr (str[POS + 1] == ':') {
+      using type = get_type<ID, Args>;
+      constexpr auto result = parse_specs<type>(str, POS + 2, ID);
+      return parse_tail<Args, result.end, result.next_arg_id>(
+          spec_field<char_type, type, ID>{result.fmt}, format_str);
+    } else {
+      return unknown_format();
+    }
+  } else if constexpr (str[POS] == '}') {
+    if (POS + 1 == str.size())
+      throw format_error("unmatched '}' in format string");
+    return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), format_str);
+  } else {
+    constexpr auto end = parse_text(str, POS + 1);
+    if constexpr (end - POS > 1) {
+      return parse_tail<Args, end, ID>(make_text(str, POS, end - POS),
+                                       format_str);
+    } else {
+      return parse_tail<Args, end, ID>(code_unit<char_type>{str[POS]},
+                                       format_str);
+    }
+  }
+}
+
+template <typename... Args, typename S,
+          FMT_ENABLE_IF(is_compile_string<S>::value ||
+                        detail::is_compiled_string<S>::value)>
+constexpr auto compile(S format_str) {
+  constexpr basic_string_view<typename S::char_type> str = format_str;
+  if constexpr (str.size() == 0) {
+    return detail::make_text(str, 0, 0);
+  } else {
+    constexpr auto result =
+        detail::compile_format_string<detail::type_list<Args...>, 0, 0>(
+            format_str);
+    if constexpr (std::is_same<remove_cvref_t<decltype(result)>,
+                               detail::unknown_format>()) {
+      return detail::compiled_format<S, Args...>(to_string_view(format_str));
+    } else {
+      return result;
+    }
+  }
+}
+#else
+template <typename... Args, typename S,
+          FMT_ENABLE_IF(is_compile_string<S>::value)>
+constexpr auto compile(S format_str) -> detail::compiled_format<S, Args...> {
+  return detail::compiled_format<S, Args...>(to_string_view(format_str));
+}
+#endif  // __cpp_if_constexpr
+
+// Compiles the format string which must be a string literal.
+template <typename... Args, typename Char, size_t N>
+auto compile(const Char (&format_str)[N])
+    -> detail::compiled_format<const Char*, Args...> {
+  return detail::compiled_format<const Char*, Args...>(
+      basic_string_view<Char>(format_str, N - 1));
+}
+}  // namespace detail
+
+// DEPRECATED! use FMT_COMPILE instead.
+template <typename... Args>
+FMT_DEPRECATED auto compile(const Args&... args)
+    -> decltype(detail::compile(args...)) {
+  return detail::compile(args...);
+}
+
+#if FMT_USE_CONSTEXPR
+#  ifdef __cpp_if_constexpr
+
+template <typename CompiledFormat, typename... Args,
+          typename Char = typename CompiledFormat::char_type,
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+FMT_INLINE std::basic_string<Char> format(const CompiledFormat& cf,
+                                          const Args&... args) {
+  basic_memory_buffer<Char> buffer;
+  cf.format(detail::buffer_appender<Char>(buffer), args...);
+  return to_string(buffer);
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+OutputIt format_to(OutputIt out, const CompiledFormat& cf,
+                   const Args&... args) {
+  return cf.format(out, args...);
+}
+#  endif  // __cpp_if_constexpr
+#endif    // FMT_USE_CONSTEXPR
+
+template <typename CompiledFormat, typename... Args,
+          typename Char = typename CompiledFormat::char_type,
+          FMT_ENABLE_IF(std::is_base_of<detail::basic_compiled_format,
+                                        CompiledFormat>::value)>
+std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
+  basic_memory_buffer<Char> buffer;
+  using context = buffer_context<Char>;
+  detail::cf::vformat_to<context>(detail::buffer_appender<Char>(buffer), cf,
+                                  make_format_args<context>(args...));
+  return to_string(buffer);
+}
+
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+FMT_INLINE std::basic_string<typename S::char_type> format(const S&,
+                                                           Args&&... args) {
+#ifdef __cpp_if_constexpr
+  if constexpr (std::is_same<typename S::char_type, char>::value) {
+    constexpr basic_string_view<typename S::char_type> str = S();
+    if (str.size() == 2 && str[0] == '{' && str[1] == '}')
+      return fmt::to_string(detail::first(args...));
+  }
+#endif
+  constexpr auto compiled = detail::compile<Args...>(S());
+  return format(compiled, std::forward<Args>(args)...);
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(std::is_base_of<detail::basic_compiled_format,
+                                        CompiledFormat>::value)>
+OutputIt format_to(OutputIt out, const CompiledFormat& cf,
+                   const Args&... args) {
+  using char_type = typename CompiledFormat::char_type;
+  using context = format_context_t<OutputIt, char_type>;
+  return detail::cf::vformat_to<context>(out, cf,
+                                         make_format_args<context>(args...));
+}
+
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+OutputIt format_to(OutputIt out, const S&, const Args&... args) {
+  constexpr auto compiled = detail::compile<Args...>(S());
+  return format_to(out, compiled, args...);
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args>
+auto format_to_n(OutputIt out, size_t n, const CompiledFormat& cf,
+                 const Args&... args) ->
+    typename std::enable_if<
+        detail::is_output_iterator<OutputIt,
+                                   typename CompiledFormat::char_type>::value &&
+            std::is_base_of<detail::basic_compiled_format,
+                            CompiledFormat>::value,
+        format_to_n_result<OutputIt>>::type {
+  auto it =
+      format_to(detail::truncating_iterator<OutputIt>(out, n), cf, args...);
+  return {it.base(), it.count()};
+}
+
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+format_to_n_result<OutputIt> format_to_n(OutputIt out, size_t n, const S&,
+                                         const Args&... args) {
+  constexpr auto compiled = detail::compile<Args...>(S());
+  auto it = format_to(detail::truncating_iterator<OutputIt>(out, n), compiled,
+                      args...);
+  return {it.base(), it.count()};
+}
+
+template <typename CompiledFormat, typename... Args>
+size_t formatted_size(const CompiledFormat& cf, const Args&... args) {
+  return format_to(detail::counting_iterator(), cf, args...).count();
+}
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_COMPILE_H_

include/fmt/locale.h

@@ -8,68 +8,55 @@
 #ifndef FMT_LOCALE_H_
 #define FMT_LOCALE_H_
 
-#include "format.h"
 #include <locale>
 
+#include "format.h"
+
 FMT_BEGIN_NAMESPACE
 
-namespace internal {
-template <typename Char>
-typename buffer_context<Char>::type::iterator vformat_to(
-    const std::locale &loc, basic_buffer<Char> &buf,
-    basic_string_view<Char> format_str,
-    basic_format_args<typename buffer_context<Char>::type> args) {
-  typedef back_insert_range<basic_buffer<Char> > range;
-  return vformat_to<arg_formatter<range>>(
-    buf, to_string_view(format_str), args, internal::locale_ref(loc));
-}
-
+namespace detail {
 template <typename Char>
 std::basic_string<Char> vformat(
-    const std::locale &loc, basic_string_view<Char> format_str,
-    basic_format_args<typename buffer_context<Char>::type> args) {
+    const std::locale& loc, basic_string_view<Char> format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buffer;
-  internal::vformat_to(loc, buffer, format_str, args);
+  detail::vformat_to(buffer, format_str, args, detail::locale_ref(loc));
   return fmt::to_string(buffer);
 }
-}
+}  // namespace detail
 
-template <typename S, typename Char = FMT_CHAR(S)>
+template <typename S, typename Char = char_t<S>>
 inline std::basic_string<Char> vformat(
-    const std::locale &loc, const S &format_str,
-    basic_format_args<typename buffer_context<Char>::type> args) {
-  return internal::vformat(loc, to_string_view(format_str), args);
+    const std::locale& loc, const S& format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  return detail::vformat(loc, to_string_view(format_str), args);
 }
 
-template <typename S, typename... Args>
-inline std::basic_string<FMT_CHAR(S)> format(
-    const std::locale &loc, const S &format_str, const Args &... args) {
-  return internal::vformat(
-    loc, to_string_view(format_str),
-    *internal::checked_args<S, Args...>(format_str, args...));
+template <typename S, typename... Args, typename Char = char_t<S>>
+inline std::basic_string<Char> format(const std::locale& loc,
+                                      const S& format_str, Args&&... args) {
+  return detail::vformat(loc, to_string_view(format_str),
+                         fmt::make_args_checked<Args...>(format_str, args...));
 }
 
-template <typename String, typename OutputIt, typename... Args>
-inline typename std::enable_if<internal::is_output_iterator<OutputIt>::value,
-                               OutputIt>::type
-    vformat_to(OutputIt out, const std::locale &loc, const String &format_str,
-               typename format_args_t<OutputIt, FMT_CHAR(String)>::type args) {
-  typedef output_range<OutputIt, FMT_CHAR(String)> range;
-  return vformat_to<arg_formatter<range>>(
-    range(out), to_string_view(format_str), args, internal::locale_ref(loc));
+template <typename S, typename OutputIt, typename... Args,
+          typename Char = char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value)>
+inline OutputIt vformat_to(
+    OutputIt out, const std::locale& loc, const S& format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  decltype(detail::get_buffer<Char>(out)) buf(detail::get_buffer_init(out));
+  vformat_to(buf, to_string_view(format_str), args, detail::locale_ref(loc));
+  return detail::get_iterator(buf);
 }
 
-template <typename OutputIt, typename S, typename... Args>
-inline typename std::enable_if<
-    internal::is_string<S>::value &&
-    internal::is_output_iterator<OutputIt>::value, OutputIt>::type
-    format_to(OutputIt out, const std::locale &loc, const S &format_str,
-              const Args &... args) {
-  internal::check_format_string<Args...>(format_str);
-  typedef typename format_context_t<OutputIt, FMT_CHAR(S)>::type context;
-  format_arg_store<context, Args...> as{args...};
-  return vformat_to(out, loc, to_string_view(format_str),
-                    basic_format_args<context>(as));
+template <typename OutputIt, typename S, typename... Args,
+          bool enable = detail::is_output_iterator<OutputIt, char_t<S>>::value>
+inline auto format_to(OutputIt out, const std::locale& loc,
+                      const S& format_str, Args&&... args) ->
+    typename std::enable_if<enable, OutputIt>::type {
+  const auto& vargs = fmt::make_args_checked<Args...>(format_str, args...);
+  return vformat_to(out, loc, to_string_view(format_str), vargs);
 }
 
 FMT_END_NAMESPACE

include/fmt/os.h

@@ -0,0 +1,480 @@
+// Formatting library for C++ - optional OS-specific functionality
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_OS_H_
+#define FMT_OS_H_
+
+#if defined(__MINGW32__) || defined(__CYGWIN__)
+// Workaround MinGW bug https://sourceforge.net/p/mingw/bugs/2024/.
+#  undef __STRICT_ANSI__
+#endif
+
+#include <cerrno>
+#include <clocale>  // for locale_t
+#include <cstddef>
+#include <cstdio>
+#include <cstdlib>  // for strtod_l
+
+#if defined __APPLE__ || defined(__FreeBSD__)
+#  include <xlocale.h>  // for LC_NUMERIC_MASK on OS X
+#endif
+
+#include "format.h"
+
+// UWP doesn't provide _pipe.
+#if FMT_HAS_INCLUDE("winapifamily.h")
+#  include <winapifamily.h>
+#endif
+#if (FMT_HAS_INCLUDE(<fcntl.h>) || defined(__APPLE__) || \
+     defined(__linux__)) &&                              \
+    (!defined(WINAPI_FAMILY) || (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP))
+#  include <fcntl.h>  // for O_RDONLY
+#  define FMT_USE_FCNTL 1
+#else
+#  define FMT_USE_FCNTL 0
+#endif
+
+#ifndef FMT_POSIX
+#  if defined(_WIN32) && !defined(__MINGW32__)
+// Fix warnings about deprecated symbols.
+#    define FMT_POSIX(call) _##call
+#  else
+#    define FMT_POSIX(call) call
+#  endif
+#endif
+
+// Calls to system functions are wrapped in FMT_SYSTEM for testability.
+#ifdef FMT_SYSTEM
+#  define FMT_POSIX_CALL(call) FMT_SYSTEM(call)
+#else
+#  define FMT_SYSTEM(call) ::call
+#  ifdef _WIN32
+// Fix warnings about deprecated symbols.
+#    define FMT_POSIX_CALL(call) ::_##call
+#  else
+#    define FMT_POSIX_CALL(call) ::call
+#  endif
+#endif
+
+// Retries the expression while it evaluates to error_result and errno
+// equals to EINTR.
+#ifndef _WIN32
+#  define FMT_RETRY_VAL(result, expression, error_result) \
+    do {                                                  \
+      (result) = (expression);                            \
+    } while ((result) == (error_result) && errno == EINTR)
+#else
+#  define FMT_RETRY_VAL(result, expression, error_result) result = (expression)
+#endif
+
+#define FMT_RETRY(result, expression) FMT_RETRY_VAL(result, expression, -1)
+
+FMT_BEGIN_NAMESPACE
+
+/**
+  \rst
+  A reference to a null-terminated string. It can be constructed from a C
+  string or ``std::string``.
+
+  You can use one of the following type aliases for common character types:
+
+  +---------------+-----------------------------+
+  | Type          | Definition                  |
+  +===============+=============================+
+  | cstring_view  | basic_cstring_view<char>    |
+  +---------------+-----------------------------+
+  | wcstring_view | basic_cstring_view<wchar_t> |
+  +---------------+-----------------------------+
+
+  This class is most useful as a parameter type to allow passing
+  different types of strings to a function, for example::
+
+    template <typename... Args>
+    std::string format(cstring_view format_str, const Args & ... args);
+
+    format("{}", 42);
+    format(std::string("{}"), 42);
+  \endrst
+ */
+template <typename Char> class basic_cstring_view {
+ private:
+  const Char* data_;
+
+ public:
+  /** Constructs a string reference object from a C string. */
+  basic_cstring_view(const Char* s) : data_(s) {}
+
+  /**
+    \rst
+    Constructs a string reference from an ``std::string`` object.
+    \endrst
+   */
+  basic_cstring_view(const std::basic_string<Char>& s) : data_(s.c_str()) {}
+
+  /** Returns the pointer to a C string. */
+  const Char* c_str() const { return data_; }
+};
+
+using cstring_view = basic_cstring_view<char>;
+using wcstring_view = basic_cstring_view<wchar_t>;
+
+// An error code.
+class error_code {
+ private:
+  int value_;
+
+ public:
+  explicit error_code(int value = 0) FMT_NOEXCEPT : value_(value) {}
+
+  int get() const FMT_NOEXCEPT { return value_; }
+};
+
+#ifdef _WIN32
+namespace detail {
+// A converter from UTF-16 to UTF-8.
+// It is only provided for Windows since other systems support UTF-8 natively.
+class utf16_to_utf8 {
+ private:
+  memory_buffer buffer_;
+
+ public:
+  utf16_to_utf8() {}
+  FMT_API explicit utf16_to_utf8(wstring_view s);
+  operator string_view() const { return string_view(&buffer_[0], size()); }
+  size_t size() const { return buffer_.size() - 1; }
+  const char* c_str() const { return &buffer_[0]; }
+  std::string str() const { return std::string(&buffer_[0], size()); }
+
+  // Performs conversion returning a system error code instead of
+  // throwing exception on conversion error. This method may still throw
+  // in case of memory allocation error.
+  FMT_API int convert(wstring_view s);
+};
+
+FMT_API void format_windows_error(buffer<char>& out, int error_code,
+                                  string_view message) FMT_NOEXCEPT;
+}  // namespace detail
+
+/** A Windows error. */
+class windows_error : public system_error {
+ private:
+  FMT_API void init(int error_code, string_view format_str, format_args args);
+
+ public:
+  /**
+   \rst
+   Constructs a :class:`fmt::windows_error` object with the description
+   of the form
+
+   .. parsed-literal::
+     *<message>*: *<system-message>*
+
+   where *<message>* is the formatted message and *<system-message>* is the
+   system message corresponding to the error code.
+   *error_code* is a Windows error code as given by ``GetLastError``.
+   If *error_code* is not a valid error code such as -1, the system message
+   will look like "error -1".
+
+   **Example**::
+
+     // This throws a windows_error with the description
+     //   cannot open file 'madeup': The system cannot find the file specified.
+     // or similar (system message may vary).
+     const char *filename = "madeup";
+     LPOFSTRUCT of = LPOFSTRUCT();
+     HFILE file = OpenFile(filename, &of, OF_READ);
+     if (file == HFILE_ERROR) {
+       throw fmt::windows_error(GetLastError(),
+                                "cannot open file '{}'", filename);
+     }
+   \endrst
+  */
+  template <typename... Args>
+  windows_error(int error_code, string_view message, const Args&... args) {
+    init(error_code, message, make_format_args(args...));
+  }
+};
+
+// Reports a Windows error without throwing an exception.
+// Can be used to report errors from destructors.
+FMT_API void report_windows_error(int error_code,
+                                  string_view message) FMT_NOEXCEPT;
+#endif  // _WIN32
+
+// A buffered file.
+class buffered_file {
+ private:
+  FILE* file_;
+
+  friend class file;
+
+  explicit buffered_file(FILE* f) : file_(f) {}
+
+ public:
+  buffered_file(const buffered_file&) = delete;
+  void operator=(const buffered_file&) = delete;
+
+  // Constructs a buffered_file object which doesn't represent any file.
+  buffered_file() FMT_NOEXCEPT : file_(nullptr) {}
+
+  // Destroys the object closing the file it represents if any.
+  FMT_API ~buffered_file() FMT_NOEXCEPT;
+
+ public:
+  buffered_file(buffered_file&& other) FMT_NOEXCEPT : file_(other.file_) {
+    other.file_ = nullptr;
+  }
+
+  buffered_file& operator=(buffered_file&& other) {
+    close();
+    file_ = other.file_;
+    other.file_ = nullptr;
+    return *this;
+  }
+
+  // Opens a file.
+  FMT_API buffered_file(cstring_view filename, cstring_view mode);
+
+  // Closes the file.
+  FMT_API void close();
+
+  // Returns the pointer to a FILE object representing this file.
+  FILE* get() const FMT_NOEXCEPT { return file_; }
+
+  // We place parentheses around fileno to workaround a bug in some versions
+  // of MinGW that define fileno as a macro.
+  FMT_API int(fileno)() const;
+
+  void vprint(string_view format_str, format_args args) {
+    fmt::vprint(file_, format_str, args);
+  }
+
+  template <typename... Args>
+  inline void print(string_view format_str, const Args&... args) {
+    vprint(format_str, make_format_args(args...));
+  }
+};
+
+#if FMT_USE_FCNTL
+// A file. Closed file is represented by a file object with descriptor -1.
+// Methods that are not declared with FMT_NOEXCEPT may throw
+// fmt::system_error in case of failure. Note that some errors such as
+// closing the file multiple times will cause a crash on Windows rather
+// than an exception. You can get standard behavior by overriding the
+// invalid parameter handler with _set_invalid_parameter_handler.
+class file {
+ private:
+  int fd_;  // File descriptor.
+
+  // Constructs a file object with a given descriptor.
+  explicit file(int fd) : fd_(fd) {}
+
+ public:
+  // Possible values for the oflag argument to the constructor.
+  enum {
+    RDONLY = FMT_POSIX(O_RDONLY),  // Open for reading only.
+    WRONLY = FMT_POSIX(O_WRONLY),  // Open for writing only.
+    RDWR = FMT_POSIX(O_RDWR),      // Open for reading and writing.
+    CREATE = FMT_POSIX(O_CREAT),   // Create if the file doesn't exist.
+    APPEND = FMT_POSIX(O_APPEND)   // Open in append mode.
+  };
+
+  // Constructs a file object which doesn't represent any file.
+  file() FMT_NOEXCEPT : fd_(-1) {}
+
+  // Opens a file and constructs a file object representing this file.
+  FMT_API file(cstring_view path, int oflag);
+
+ public:
+  file(const file&) = delete;
+  void operator=(const file&) = delete;
+
+  file(file&& other) FMT_NOEXCEPT : fd_(other.fd_) { other.fd_ = -1; }
+
+  file& operator=(file&& other) FMT_NOEXCEPT {
+    close();
+    fd_ = other.fd_;
+    other.fd_ = -1;
+    return *this;
+  }
+
+  // Destroys the object closing the file it represents if any.
+  FMT_API ~file() FMT_NOEXCEPT;
+
+  // Returns the file descriptor.
+  int descriptor() const FMT_NOEXCEPT { return fd_; }
+
+  // Closes the file.
+  FMT_API void close();
+
+  // Returns the file size. The size has signed type for consistency with
+  // stat::st_size.
+  FMT_API long long size() const;
+
+  // Attempts to read count bytes from the file into the specified buffer.
+  FMT_API size_t read(void* buffer, size_t count);
+
+  // Attempts to write count bytes from the specified buffer to the file.
+  FMT_API size_t write(const void* buffer, size_t count);
+
+  // Duplicates a file descriptor with the dup function and returns
+  // the duplicate as a file object.
+  FMT_API static file dup(int fd);
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  FMT_API void dup2(int fd);
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  FMT_API void dup2(int fd, error_code& ec) FMT_NOEXCEPT;
+
+  // Creates a pipe setting up read_end and write_end file objects for reading
+  // and writing respectively.
+  FMT_API static void pipe(file& read_end, file& write_end);
+
+  // Creates a buffered_file object associated with this file and detaches
+  // this file object from the file.
+  FMT_API buffered_file fdopen(const char* mode);
+};
+
+// Returns the memory page size.
+long getpagesize();
+
+namespace detail {
+
+struct buffer_size {
+  size_t value = 0;
+  buffer_size operator=(size_t val) const {
+    auto bs = buffer_size();
+    bs.value = val;
+    return bs;
+  }
+};
+
+struct ostream_params {
+  int oflag = file::WRONLY | file::CREATE;
+  size_t buffer_size = BUFSIZ > 32768 ? BUFSIZ : 32768;
+
+  ostream_params() {}
+
+  template <typename... T>
+  ostream_params(T... params, int oflag) : ostream_params(params...) {
+    this->oflag = oflag;
+  }
+
+  template <typename... T>
+  ostream_params(T... params, detail::buffer_size bs)
+      : ostream_params(params...) {
+    this->buffer_size = bs.value;
+  }
+};
+}  // namespace detail
+
+static constexpr detail::buffer_size buffer_size;
+
+// A fast output stream which is not thread-safe.
+class ostream final : private detail::buffer<char> {
+ private:
+  file file_;
+
+  void flush() {
+    if (size() == 0) return;
+    file_.write(data(), size());
+    clear();
+  }
+
+  void grow(size_t) final;
+
+  ostream(cstring_view path, const detail::ostream_params& params)
+      : file_(path, params.oflag) {
+    set(new char[params.buffer_size], params.buffer_size);
+  }
+
+ public:
+  ostream(ostream&& other)
+      : detail::buffer<char>(other.data(), other.size(), other.capacity()),
+        file_(std::move(other.file_)) {
+    other.set(nullptr, 0);
+  }
+  ~ostream() {
+    flush();
+    delete[] data();
+  }
+
+  template <typename... T>
+  friend ostream output_file(cstring_view path, T... params);
+
+  void close() {
+    flush();
+    file_.close();
+  }
+
+  template <typename S, typename... Args>
+  void print(const S& format_str, const Args&... args) {
+    format_to(detail::buffer_appender<char>(*this), format_str, args...);
+  }
+};
+
+/**
+  Opens a file for writing. Supported parameters passed in `params`:
+  * ``<integer>``: Output flags (``file::WRONLY | file::CREATE`` by default)
+  * ``buffer_size=<integer>``: Output buffer size
+ */
+template <typename... T>
+inline ostream output_file(cstring_view path, T... params) {
+  return {path, detail::ostream_params(params...)};
+}
+#endif  // FMT_USE_FCNTL
+
+#ifdef FMT_LOCALE
+// A "C" numeric locale.
+class locale {
+ private:
+#  ifdef _WIN32
+  using locale_t = _locale_t;
+
+  static void freelocale(locale_t loc) { _free_locale(loc); }
+
+  static double strtod_l(const char* nptr, char** endptr, _locale_t loc) {
+    return _strtod_l(nptr, endptr, loc);
+  }
+#  endif
+
+  locale_t locale_;
+
+ public:
+  using type = locale_t;
+  locale(const locale&) = delete;
+  void operator=(const locale&) = delete;
+
+  locale() {
+#  ifndef _WIN32
+    locale_ = FMT_SYSTEM(newlocale(LC_NUMERIC_MASK, "C", nullptr));
+#  else
+    locale_ = _create_locale(LC_NUMERIC, "C");
+#  endif
+    if (!locale_) FMT_THROW(system_error(errno, "cannot create locale"));
+  }
+  ~locale() { freelocale(locale_); }
+
+  type get() const { return locale_; }
+
+  // Converts string to floating-point number and advances str past the end
+  // of the parsed input.
+  double strtod(const char*& str) const {
+    char* end = nullptr;
+    double result = strtod_l(str, &end, locale_);
+    str = end;
+    return result;
+  }
+};
+using Locale FMT_DEPRECATED_ALIAS = locale;
+#endif  // FMT_LOCALE
+FMT_END_NAMESPACE
+
+#endif  // FMT_OS_H_

include/fmt/ostream.h

@@ -8,22 +8,26 @@
 #ifndef FMT_OSTREAM_H_
 #define FMT_OSTREAM_H_
 
-#include "format.h"
 #include <ostream>
 
+#include "format.h"
+
 FMT_BEGIN_NAMESPACE
-namespace internal {
 
-template <class Char>
-class formatbuf : public std::basic_streambuf<Char> {
+template <typename Char> class basic_printf_parse_context;
+template <typename OutputIt, typename Char> class basic_printf_context;
+
+namespace detail {
+
+template <class Char> class formatbuf : public std::basic_streambuf<Char> {
  private:
-  typedef typename std::basic_streambuf<Char>::int_type int_type;
-  typedef typename std::basic_streambuf<Char>::traits_type traits_type;
+  using int_type = typename std::basic_streambuf<Char>::int_type;
+  using traits_type = typename std::basic_streambuf<Char>::traits_type;
 
-  basic_buffer<Char> &buffer_;
+  buffer<Char>& buffer_;
 
  public:
-  formatbuf(basic_buffer<Char> &buffer) : buffer_(buffer) {}
+  formatbuf(buffer<Char>& buf) : buffer_(buf) {}
 
  protected:
   // The put-area is actually always empty. This makes the implementation
@@ -39,33 +43,46 @@ class formatbuf : public std::basic_streambuf<Char> {
     return ch;
   }
 
-  std::streamsize xsputn(const Char *s, std::streamsize count) FMT_OVERRIDE {
+  std::streamsize xsputn(const Char* s, std::streamsize count) FMT_OVERRIDE {
     buffer_.append(s, s + count);
     return count;
   }
 };
 
-template <typename Char>
-struct test_stream : std::basic_ostream<Char> {
- private:
-  struct null;
-  // Hide all operator<< from std::basic_ostream<Char>.
-  void operator<<(null);
+struct converter {
+  template <typename T, FMT_ENABLE_IF(is_integral<T>::value)> converter(T);
 };
 
-// Checks if T has a user-defined operator<< (e.g. not a member of std::ostream).
-template <typename T, typename Char>
-class is_streamable {
+template <typename Char> struct test_stream : std::basic_ostream<Char> {
+ private:
+  void_t<> operator<<(converter);
+};
+
+// Hide insertion operators for built-in types.
+template <typename Char, typename Traits>
+void_t<> operator<<(std::basic_ostream<Char, Traits>&, Char);
+template <typename Char, typename Traits>
+void_t<> operator<<(std::basic_ostream<Char, Traits>&, char);
+template <typename Traits>
+void_t<> operator<<(std::basic_ostream<char, Traits>&, char);
+template <typename Traits>
+void_t<> operator<<(std::basic_ostream<char, Traits>&, signed char);
+template <typename Traits>
+void_t<> operator<<(std::basic_ostream<char, Traits>&, unsigned char);
+
+// Checks if T has a user-defined operator<< (e.g. not a member of
+// std::ostream).
+template <typename T, typename Char> class is_streamable {
  private:
   template <typename U>
-  static decltype(
-    internal::declval<test_stream<Char>&>()
-      << internal::declval<U>(), std::true_type()) test(int);
+  static bool_constant<!std::is_same<decltype(std::declval<test_stream<Char>&>()
+                                              << std::declval<U>()),
+                                     void_t<>>::value>
+  test(int);
 
-  template <typename>
-  static std::false_type test(...);
+  template <typename> static std::false_type test(...);
 
-  typedef decltype(test<T>(0)) result;
+  using result = decltype(test<T>(0));
 
  public:
   static const bool value = result::value;
@@ -73,65 +90,73 @@ class is_streamable {
 
 // Write the content of buf to os.
 template <typename Char>
-void write(std::basic_ostream<Char> &os, basic_buffer<Char> &buf) {
-  const Char *data = buf.data();
-  typedef std::make_unsigned<std::streamsize>::type UnsignedStreamSize;
-  UnsignedStreamSize size = buf.size();
-  UnsignedStreamSize max_size =
-      internal::to_unsigned((std::numeric_limits<std::streamsize>::max)());
+void write_buffer(std::basic_ostream<Char>& os, buffer<Char>& buf) {
+  const Char* buf_data = buf.data();
+  using unsigned_streamsize = std::make_unsigned<std::streamsize>::type;
+  unsigned_streamsize size = buf.size();
+  unsigned_streamsize max_size = to_unsigned(max_value<std::streamsize>());
   do {
-    UnsignedStreamSize n = size <= max_size ? size : max_size;
-    os.write(data, static_cast<std::streamsize>(n));
-    data += n;
+    unsigned_streamsize n = size <= max_size ? size : max_size;
+    os.write(buf_data, static_cast<std::streamsize>(n));
+    buf_data += n;
     size -= n;
   } while (size != 0);
 }
 
 template <typename Char, typename T>
-void format_value(basic_buffer<Char> &buffer, const T &value) {
-  internal::formatbuf<Char> format_buf(buffer);
+void format_value(buffer<Char>& buf, const T& value,
+                  locale_ref loc = locale_ref()) {
+  formatbuf<Char> format_buf(buf);
   std::basic_ostream<Char> output(&format_buf);
-  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
+#if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
+  if (loc) output.imbue(loc.get<std::locale>());
+#endif
   output << value;
-  buffer.resize(buffer.size());
+  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
+  buf.try_resize(buf.size());
 }
-}  // namespace internal
-
-// Disable conversion to int if T has an overloaded operator<< which is a free
-// function (not a member of std::ostream).
-template <typename T, typename Char>
-struct convert_to_int<T, Char, void> {
-  static const bool value =
-    convert_to_int<T, Char, int>::value &&
-    !internal::is_streamable<T, Char>::value;
-};
 
 // Formats an object of type T that has an overloaded ostream operator<<.
 template <typename T, typename Char>
-struct formatter<T, Char,
-    typename std::enable_if<
-      internal::is_streamable<T, Char>::value &&
-      !internal::format_type<
-        typename buffer_context<Char>::type, T>::value>::type>
-    : formatter<basic_string_view<Char>, Char> {
+struct fallback_formatter<T, Char, enable_if_t<is_streamable<T, Char>::value>>
+    : private formatter<basic_string_view<Char>, Char> {
+  FMT_CONSTEXPR auto parse(basic_format_parse_context<Char>& ctx)
+      -> decltype(ctx.begin()) {
+    return formatter<basic_string_view<Char>, Char>::parse(ctx);
+  }
+  template <typename ParseCtx,
+            FMT_ENABLE_IF(std::is_same<
+                          ParseCtx, basic_printf_parse_context<Char>>::value)>
+  auto parse(ParseCtx& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
 
-  template <typename Context>
-  auto format(const T &value, Context &ctx) -> decltype(ctx.out()) {
+  template <typename OutputIt>
+  auto format(const T& value, basic_format_context<OutputIt, Char>& ctx)
+      -> OutputIt {
     basic_memory_buffer<Char> buffer;
-    internal::format_value(buffer, value);
+    format_value(buffer, value, ctx.locale());
     basic_string_view<Char> str(buffer.data(), buffer.size());
     return formatter<basic_string_view<Char>, Char>::format(str, ctx);
   }
+  template <typename OutputIt>
+  auto format(const T& value, basic_printf_context<OutputIt, Char>& ctx)
+      -> OutputIt {
+    basic_memory_buffer<Char> buffer;
+    format_value(buffer, value, ctx.locale());
+    return std::copy(buffer.begin(), buffer.end(), ctx.out());
+  }
 };
+}  // namespace detail
 
 template <typename Char>
-inline void vprint(std::basic_ostream<Char> &os,
-                   basic_string_view<Char> format_str,
-                   basic_format_args<typename buffer_context<Char>::type> args) {
+void vprint(std::basic_ostream<Char>& os, basic_string_view<Char> format_str,
+            basic_format_args<buffer_context<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buffer;
-  internal::vformat_to(buffer, format_str, args);
-  internal::write(os, buffer);
+  detail::vformat_to(buffer, format_str, args);
+  detail::write_buffer(os, buffer);
 }
+
 /**
   \rst
   Prints formatted data to the stream *os*.
@@ -141,12 +166,11 @@ inline void vprint(std::basic_ostream<Char> &os,
     fmt::print(cerr, "Don't {}!", "panic");
   \endrst
  */
-template <typename S, typename... Args>
-inline typename std::enable_if<internal::is_string<S>::value>::type
-print(std::basic_ostream<FMT_CHAR(S)> &os, const S &format_str,
-      const Args & ... args) {
-  internal::checked_args<S, Args...> ca(format_str, args...);
-  vprint(os, to_string_view(format_str), *ca);
+template <typename S, typename... Args,
+          typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>>
+void print(std::basic_ostream<Char>& os, const S& format_str, Args&&... args) {
+  vprint(os, to_string_view(format_str),
+         fmt::make_args_checked<Args...>(format_str, args...));
 }
 FMT_END_NAMESPACE
 

include/fmt/posix.h

@@ -1,324 +1,2 @@
-// A C++ interface to POSIX functions.
-//
-// Copyright (c) 2012 - 2016, Victor Zverovich
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-#ifndef FMT_POSIX_H_
-#define FMT_POSIX_H_
-
-#if defined(__MINGW32__) || defined(__CYGWIN__)
-// Workaround MinGW bug https://sourceforge.net/p/mingw/bugs/2024/.
-# undef __STRICT_ANSI__
-#endif
-
-#include <errno.h>
-#include <fcntl.h>   // for O_RDONLY
-#include <locale.h>  // for locale_t
-#include <stdio.h>
-#include <stdlib.h>  // for strtod_l
-
-#include <cstddef>
-
-#if defined __APPLE__ || defined(__FreeBSD__)
-# include <xlocale.h>  // for LC_NUMERIC_MASK on OS X
-#endif
-
-#include "format.h"
-
-#ifndef FMT_POSIX
-# if defined(_WIN32) && !defined(__MINGW32__)
-// Fix warnings about deprecated symbols.
-#  define FMT_POSIX(call) _##call
-# else
-#  define FMT_POSIX(call) call
-# endif
-#endif
-
-// Calls to system functions are wrapped in FMT_SYSTEM for testability.
-#ifdef FMT_SYSTEM
-# define FMT_POSIX_CALL(call) FMT_SYSTEM(call)
-#else
-# define FMT_SYSTEM(call) call
-# ifdef _WIN32
-// Fix warnings about deprecated symbols.
-#  define FMT_POSIX_CALL(call) ::_##call
-# else
-#  define FMT_POSIX_CALL(call) ::call
-# endif
-#endif
-
-// Retries the expression while it evaluates to error_result and errno
-// equals to EINTR.
-#ifndef _WIN32
-# define FMT_RETRY_VAL(result, expression, error_result) \
-  do { \
-    result = (expression); \
-  } while (result == error_result && errno == EINTR)
-#else
-# define FMT_RETRY_VAL(result, expression, error_result) result = (expression)
-#endif
-
-#define FMT_RETRY(result, expression) FMT_RETRY_VAL(result, expression, -1)
-
-FMT_BEGIN_NAMESPACE
-
-/**
-  \rst
-  A reference to a null-terminated string. It can be constructed from a C
-  string or ``std::string``.
-
-  You can use one of the following typedefs for common character types:
-
-  +---------------+-----------------------------+
-  | Type          | Definition                  |
-  +===============+=============================+
-  | cstring_view  | basic_cstring_view<char>    |
-  +---------------+-----------------------------+
-  | wcstring_view | basic_cstring_view<wchar_t> |
-  +---------------+-----------------------------+
-
-  This class is most useful as a parameter type to allow passing
-  different types of strings to a function, for example::
-
-    template <typename... Args>
-    std::string format(cstring_view format_str, const Args & ... args);
-
-    format("{}", 42);
-    format(std::string("{}"), 42);
-  \endrst
- */
-template <typename Char>
-class basic_cstring_view {
- private:
-  const Char *data_;
-
- public:
-  /** Constructs a string reference object from a C string. */
-  basic_cstring_view(const Char *s) : data_(s) {}
-
-  /**
-    \rst
-    Constructs a string reference from an ``std::string`` object.
-    \endrst
-   */
-  basic_cstring_view(const std::basic_string<Char> &s) : data_(s.c_str()) {}
-
-  /** Returns the pointer to a C string. */
-  const Char *c_str() const { return data_; }
-};
-
-typedef basic_cstring_view<char> cstring_view;
-typedef basic_cstring_view<wchar_t> wcstring_view;
-
-// An error code.
-class error_code {
- private:
-  int value_;
-
- public:
-  explicit error_code(int value = 0) FMT_NOEXCEPT : value_(value) {}
-
-  int get() const FMT_NOEXCEPT { return value_; }
-};
-
-// A buffered file.
-class buffered_file {
- private:
-  FILE *file_;
-
-  friend class file;
-
-  explicit buffered_file(FILE *f) : file_(f) {}
-
- public:
-  // Constructs a buffered_file object which doesn't represent any file.
-  buffered_file() FMT_NOEXCEPT : file_(FMT_NULL) {}
-
-  // Destroys the object closing the file it represents if any.
-  FMT_API ~buffered_file() FMT_NOEXCEPT;
-
- private:
-  buffered_file(const buffered_file &) = delete;
-  void operator=(const buffered_file &) = delete;
-
-
- public:
-  buffered_file(buffered_file &&other) FMT_NOEXCEPT : file_(other.file_) {
-    other.file_ = FMT_NULL;
-  }
-
-  buffered_file& operator=(buffered_file &&other) {
-    close();
-    file_ = other.file_;
-    other.file_ = FMT_NULL;
-    return *this;
-  }
-
-  // Opens a file.
-  FMT_API buffered_file(cstring_view filename, cstring_view mode);
-
-  // Closes the file.
-  FMT_API void close();
-
-  // Returns the pointer to a FILE object representing this file.
-  FILE *get() const FMT_NOEXCEPT { return file_; }
-
-  // We place parentheses around fileno to workaround a bug in some versions
-  // of MinGW that define fileno as a macro.
-  FMT_API int (fileno)() const;
-
-  void vprint(string_view format_str, format_args args) {
-    fmt::vprint(file_, format_str, args);
-  }
-
-  template <typename... Args>
-  inline void print(string_view format_str, const Args & ... args) {
-    vprint(format_str, make_format_args(args...));
-  }
-};
-
-// A file. Closed file is represented by a file object with descriptor -1.
-// Methods that are not declared with FMT_NOEXCEPT may throw
-// fmt::system_error in case of failure. Note that some errors such as
-// closing the file multiple times will cause a crash on Windows rather
-// than an exception. You can get standard behavior by overriding the
-// invalid parameter handler with _set_invalid_parameter_handler.
-class file {
- private:
-  int fd_;  // File descriptor.
-
-  // Constructs a file object with a given descriptor.
-  explicit file(int fd) : fd_(fd) {}
-
- public:
-  // Possible values for the oflag argument to the constructor.
-  enum {
-    RDONLY = FMT_POSIX(O_RDONLY), // Open for reading only.
-    WRONLY = FMT_POSIX(O_WRONLY), // Open for writing only.
-    RDWR   = FMT_POSIX(O_RDWR)    // Open for reading and writing.
-  };
-
-  // Constructs a file object which doesn't represent any file.
-  file() FMT_NOEXCEPT : fd_(-1) {}
-
-  // Opens a file and constructs a file object representing this file.
-  FMT_API file(cstring_view path, int oflag);
-
- private:
-  file(const file &) = delete;
-  void operator=(const file &) = delete;
-
- public:
-  file(file &&other) FMT_NOEXCEPT : fd_(other.fd_) {
-    other.fd_ = -1;
-  }
-
-  file& operator=(file &&other) {
-    close();
-    fd_ = other.fd_;
-    other.fd_ = -1;
-    return *this;
-  }
-
-  // Destroys the object closing the file it represents if any.
-  FMT_API ~file() FMT_NOEXCEPT;
-
-  // Returns the file descriptor.
-  int descriptor() const FMT_NOEXCEPT { return fd_; }
-
-  // Closes the file.
-  FMT_API void close();
-
-  // Returns the file size. The size has signed type for consistency with
-  // stat::st_size.
-  FMT_API long long size() const;
-
-  // Attempts to read count bytes from the file into the specified buffer.
-  FMT_API std::size_t read(void *buffer, std::size_t count);
-
-  // Attempts to write count bytes from the specified buffer to the file.
-  FMT_API std::size_t write(const void *buffer, std::size_t count);
-
-  // Duplicates a file descriptor with the dup function and returns
-  // the duplicate as a file object.
-  FMT_API static file dup(int fd);
-
-  // Makes fd be the copy of this file descriptor, closing fd first if
-  // necessary.
-  FMT_API void dup2(int fd);
-
-  // Makes fd be the copy of this file descriptor, closing fd first if
-  // necessary.
-  FMT_API void dup2(int fd, error_code &ec) FMT_NOEXCEPT;
-
-  // Creates a pipe setting up read_end and write_end file objects for reading
-  // and writing respectively.
-  FMT_API static void pipe(file &read_end, file &write_end);
-
-  // Creates a buffered_file object associated with this file and detaches
-  // this file object from the file.
-  FMT_API buffered_file fdopen(const char *mode);
-};
-
-// Returns the memory page size.
-long getpagesize();
-
-#if (defined(LC_NUMERIC_MASK) || defined(_MSC_VER)) && \
-    !defined(__ANDROID__) && !defined(__CYGWIN__) && !defined(__OpenBSD__) && \
-    !defined(__NEWLIB_H__)
-# define FMT_LOCALE
-#endif
-
-#ifdef FMT_LOCALE
-// A "C" numeric locale.
-class Locale {
- private:
-# ifdef _MSC_VER
-  typedef _locale_t locale_t;
-
-  enum { LC_NUMERIC_MASK = LC_NUMERIC };
-
-  static locale_t newlocale(int category_mask, const char *locale, locale_t) {
-    return _create_locale(category_mask, locale);
-  }
-
-  static void freelocale(locale_t locale) {
-    _free_locale(locale);
-  }
-
-  static double strtod_l(const char *nptr, char **endptr, _locale_t locale) {
-    return _strtod_l(nptr, endptr, locale);
-  }
-# endif
-
-  locale_t locale_;
-
-  Locale(const Locale &) = delete;
-  void operator=(const Locale &) = delete;
-
- public:
-  typedef locale_t Type;
-
-  Locale() : locale_(newlocale(LC_NUMERIC_MASK, "C", FMT_NULL)) {
-    if (!locale_)
-      FMT_THROW(system_error(errno, "cannot create locale"));
-  }
-  ~Locale() { freelocale(locale_); }
-
-  Type get() const { return locale_; }
-
-  // Converts string to floating-point number and advances str past the end
-  // of the parsed input.
-  double strtod(const char *&str) const {
-    char *end = FMT_NULL;
-    double result = strtod_l(str, &end, locale_);
-    str = end;
-    return result;
-  }
-};
-#endif  // FMT_LOCALE
-FMT_END_NAMESPACE
-
-#endif  // FMT_POSIX_H_
+#include "os.h"
+#warning "fmt/posix.h is deprecated; use fmt/os.h instead"

include/fmt/ranges.h

@@ -1,4 +1,4 @@
-// Formatting library for C++ - the core API
+// Formatting library for C++ - experimental range support
 //
 // Copyright (c) 2012 - present, Victor Zverovich
 // All rights reserved.
@@ -12,28 +12,30 @@
 #ifndef FMT_RANGES_H_
 #define FMT_RANGES_H_
 
-#include "format.h"
+#include <initializer_list>
 #include <type_traits>
 
+#include "format.h"
+
 // output only up to N items from the range.
 #ifndef FMT_RANGE_OUTPUT_LENGTH_LIMIT
-# define FMT_RANGE_OUTPUT_LENGTH_LIMIT 256
+#  define FMT_RANGE_OUTPUT_LENGTH_LIMIT 256
 #endif
 
 FMT_BEGIN_NAMESPACE
 
-template <typename Char>
-struct formatting_base {
+template <typename Char> struct formatting_base {
   template <typename ParseContext>
-  FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
     return ctx.begin();
   }
 };
 
 template <typename Char, typename Enable = void>
 struct formatting_range : formatting_base<Char> {
-  static FMT_CONSTEXPR_DECL const std::size_t range_length_limit =
-      FMT_RANGE_OUTPUT_LENGTH_LIMIT; // output only up to N items from the range.
+  static FMT_CONSTEXPR_DECL const size_t range_length_limit =
+      FMT_RANGE_OUTPUT_LENGTH_LIMIT;  // output only up to N items from the
+                                      // range.
   Char prefix;
   Char delimiter;
   Char postfix;
@@ -52,106 +54,92 @@ struct formatting_tuple : formatting_base<Char> {
   static FMT_CONSTEXPR_DECL const bool add_prepostfix_space = false;
 };
 
-namespace internal {
+namespace detail {
 
 template <typename RangeT, typename OutputIterator>
-void copy(const RangeT &range, OutputIterator out) {
+OutputIterator copy(const RangeT& range, OutputIterator out) {
   for (auto it = range.begin(), end = range.end(); it != end; ++it)
     *out++ = *it;
+  return out;
 }
 
 template <typename OutputIterator>
-void copy(const char *str, OutputIterator out) {
-  const char *p_curr = str;
-  while (*p_curr) {
-    *out++ = *p_curr++;
-  }
+OutputIterator copy(const char* str, OutputIterator out) {
+  while (*str) *out++ = *str++;
+  return out;
 }
 
 template <typename OutputIterator>
-void copy(char ch, OutputIterator out) {
+OutputIterator copy(char ch, OutputIterator out) {
   *out++ = ch;
+  return out;
 }
 
 /// Return true value if T has std::string interface, like std::string_view.
-template <typename T>
-class is_like_std_string {
+template <typename T> class is_like_std_string {
   template <typename U>
-  static auto check(U *p) ->
-    decltype(p->find('a'), p->length(), p->data(), int());
-  template <typename>
-  static void check(...);
+  static auto check(U* p)
+      -> decltype((void)p->find('a'), p->length(), (void)p->data(), int());
+  template <typename> static void check(...);
 
  public:
   static FMT_CONSTEXPR_DECL const bool value =
-    !std::is_void<decltype(check<T>(FMT_NULL))>::value;
+      is_string<T>::value || !std::is_void<decltype(check<T>(nullptr))>::value;
 };
 
 template <typename Char>
 struct is_like_std_string<fmt::basic_string_view<Char>> : std::true_type {};
 
-template <typename... Ts>
-struct conditional_helper {};
+template <typename... Ts> struct conditional_helper {};
 
-template <typename T, typename _ = void>
-struct is_range_ : std::false_type {};
+template <typename T, typename _ = void> struct is_range_ : std::false_type {};
 
 #if !FMT_MSC_VER || FMT_MSC_VER > 1800
 template <typename T>
-struct is_range_<T, typename std::conditional<
-                    false,
-                    conditional_helper<decltype(internal::declval<T>().begin()),
-                                       decltype(internal::declval<T>().end())>,
-                    void>::type> : std::true_type {};
+struct is_range_<
+    T, conditional_t<false,
+                     conditional_helper<decltype(std::declval<T>().begin()),
+                                        decltype(std::declval<T>().end())>,
+                     void>> : std::true_type {};
 #endif
 
 /// tuple_size and tuple_element check.
-template <typename T>
-class is_tuple_like_ {
+template <typename T> class is_tuple_like_ {
   template <typename U>
-  static auto check(U *p) ->
-    decltype(std::tuple_size<U>::value,
-      internal::declval<typename std::tuple_element<0, U>::type>(), int());
-  template <typename>
-  static void check(...);
+  static auto check(U* p) -> decltype(std::tuple_size<U>::value, int());
+  template <typename> static void check(...);
 
  public:
   static FMT_CONSTEXPR_DECL const bool value =
-    !std::is_void<decltype(check<T>(FMT_NULL))>::value;
+      !std::is_void<decltype(check<T>(nullptr))>::value;
 };
 
 // Check for integer_sequence
 #if defined(__cpp_lib_integer_sequence) || FMT_MSC_VER >= 1900
 template <typename T, T... N>
 using integer_sequence = std::integer_sequence<T, N...>;
-template <std::size_t... N>
-using index_sequence = std::index_sequence<N...>;
-template <std::size_t N>
-using make_index_sequence = std::make_index_sequence<N>;
+template <size_t... N> using index_sequence = std::index_sequence<N...>;
+template <size_t N> using make_index_sequence = std::make_index_sequence<N>;
 #else
-template <typename T, T... N>
-struct integer_sequence {
-  typedef T value_type;
+template <typename T, T... N> struct integer_sequence {
+  using value_type = T;
 
-  static FMT_CONSTEXPR std::size_t size() {
-    return sizeof...(N);
-  }
+  static FMT_CONSTEXPR size_t size() { return sizeof...(N); }
 };
 
-template <std::size_t... N>
-using index_sequence = integer_sequence<std::size_t, N...>;
+template <size_t... N> using index_sequence = integer_sequence<size_t, N...>;
 
-template <typename T, std::size_t N, T... Ns>
+template <typename T, size_t N, T... Ns>
 struct make_integer_sequence : make_integer_sequence<T, N - 1, N - 1, Ns...> {};
 template <typename T, T... Ns>
 struct make_integer_sequence<T, 0, Ns...> : integer_sequence<T, Ns...> {};
 
-template <std::size_t N>
-using make_index_sequence = make_integer_sequence<std::size_t, N>;
+template <size_t N>
+using make_index_sequence = make_integer_sequence<size_t, N>;
 #endif
 
 template <class Tuple, class F, size_t... Is>
-void for_each(index_sequence<Is...>, Tuple &&tup, F &&f) FMT_NOEXCEPT {
+void for_each(index_sequence<Is...>, Tuple&& tup, F&& f) FMT_NOEXCEPT {
   using std::get;
   // using free function get<I>(T) now.
   const int _[] = {0, ((void)f(get<Is>(tup)), 0)...};
@@ -159,26 +147,28 @@ void for_each(index_sequence<Is...>, Tuple &&tup, F &&f) FMT_NOEXCEPT {
 }
 
 template <class T>
-FMT_CONSTEXPR make_index_sequence<std::tuple_size<T>::value> 
-get_indexes(T const &) { return {}; }
+FMT_CONSTEXPR make_index_sequence<std::tuple_size<T>::value> get_indexes(
+    T const&) {
+  return {};
+}
 
-template <class Tuple, class F>
-void for_each(Tuple &&tup, F &&f) {
+template <class Tuple, class F> void for_each(Tuple&& tup, F&& f) {
   const auto indexes = get_indexes(tup);
   for_each(indexes, std::forward<Tuple>(tup), std::forward<F>(f));
 }
 
-template<typename Arg>
-FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const Arg&, 
-  typename std::enable_if<
-    !is_like_std_string<typename std::decay<Arg>::type>::value>::type* = nullptr) {
+template <typename Range>
+using value_type = remove_cvref_t<decltype(*std::declval<Range>().begin())>;
+
+template <typename Arg, FMT_ENABLE_IF(!is_like_std_string<
+                                      typename std::decay<Arg>::type>::value)>
+FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const Arg&) {
   return add_space ? " {}" : "{}";
 }
 
-template<typename Arg>
-FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const Arg&, 
-  typename std::enable_if<
-    is_like_std_string<typename std::decay<Arg>::type>::value>::type* = nullptr) {
+template <typename Arg, FMT_ENABLE_IF(is_like_std_string<
+                                      typename std::decay<Arg>::type>::value)>
+FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const Arg&) {
   return add_space ? " \"{}\"" : "\"{}\"";
 }
 
@@ -186,123 +176,218 @@ FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const char*) {
   return add_space ? " \"{}\"" : "\"{}\"";
 }
 FMT_CONSTEXPR const wchar_t* format_str_quoted(bool add_space, const wchar_t*) {
-    return add_space ? L" \"{}\"" : L"\"{}\"";
+  return add_space ? L" \"{}\"" : L"\"{}\"";
 }
 
 FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const char) {
-    return add_space ? " '{}'" : "'{}'";
+  return add_space ? " '{}'" : "'{}'";
 }
 FMT_CONSTEXPR const wchar_t* format_str_quoted(bool add_space, const wchar_t) {
-    return add_space ? L" '{}'" : L"'{}'";
+  return add_space ? L" '{}'" : L"'{}'";
 }
+}  // namespace detail
 
-}  // namespace internal
-
-template <typename T>
-struct is_tuple_like {
+template <typename T> struct is_tuple_like {
   static FMT_CONSTEXPR_DECL const bool value =
-    internal::is_tuple_like_<T>::value && !internal::is_range_<T>::value;
+      detail::is_tuple_like_<T>::value && !detail::is_range_<T>::value;
 };
 
 template <typename TupleT, typename Char>
-struct formatter<TupleT, Char, 
-    typename std::enable_if<fmt::is_tuple_like<TupleT>::value>::type> {
-private:
+struct formatter<TupleT, Char, enable_if_t<fmt::is_tuple_like<TupleT>::value>> {
+ private:
   // C++11 generic lambda for format()
-  template <typename FormatContext>
-  struct format_each {
-    template <typename T>
-    void operator()(const T& v) {
+  template <typename FormatContext> struct format_each {
+    template <typename T> void operator()(const T& v) {
       if (i > 0) {
         if (formatting.add_prepostfix_space) {
           *out++ = ' ';
         }
-        internal::copy(formatting.delimiter, out);
+        out = detail::copy(formatting.delimiter, out);
       }
-      format_to(out,
-                internal::format_str_quoted(
-                    (formatting.add_delimiter_spaces && i > 0), v),
-                v);
+      out = format_to(out,
+                      detail::format_str_quoted(
+                          (formatting.add_delimiter_spaces && i > 0), v),
+                      v);
       ++i;
     }
 
     formatting_tuple<Char>& formatting;
-    std::size_t& i;
-    typename std::add_lvalue_reference<decltype(std::declval<FormatContext>().out())>::type out;
+    size_t& i;
+    typename std::add_lvalue_reference<decltype(
+        std::declval<FormatContext>().out())>::type out;
   };
 
-public:
+ public:
   formatting_tuple<Char> formatting;
 
   template <typename ParseContext>
-  FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
     return formatting.parse(ctx);
   }
 
   template <typename FormatContext = format_context>
-  auto format(const TupleT &values, FormatContext &ctx) -> decltype(ctx.out()) {
+  auto format(const TupleT& values, FormatContext& ctx) -> decltype(ctx.out()) {
     auto out = ctx.out();
-    std::size_t i = 0;
-    internal::copy(formatting.prefix, out);
+    size_t i = 0;
+    detail::copy(formatting.prefix, out);
 
-    internal::for_each(values, format_each<FormatContext>{formatting, i, out});
+    detail::for_each(values, format_each<FormatContext>{formatting, i, out});
     if (formatting.add_prepostfix_space) {
       *out++ = ' ';
     }
-    internal::copy(formatting.postfix, out);
+    detail::copy(formatting.postfix, out);
 
     return ctx.out();
   }
 };
 
-template <typename T>
-struct is_range {
+template <typename T, typename Char> struct is_range {
   static FMT_CONSTEXPR_DECL const bool value =
-    internal::is_range_<T>::value && !internal::is_like_std_string<T>::value;
+      detail::is_range_<T>::value && !detail::is_like_std_string<T>::value &&
+      !std::is_convertible<T, std::basic_string<Char>>::value &&
+      !std::is_constructible<detail::std_string_view<Char>, T>::value;
 };
 
-template <typename RangeT, typename Char>
-struct formatter<RangeT, Char,
-    typename std::enable_if<fmt::is_range<RangeT>::value>::type> {
-
+template <typename T, typename Char>
+struct formatter<
+    T, Char,
+    enable_if_t<fmt::is_range<T, Char>::value
+// Workaround a bug in MSVC 2017 and earlier.
+#if !FMT_MSC_VER || FMT_MSC_VER >= 1927
+                && has_formatter<detail::value_type<T>, format_context>::value
+#endif
+                >> {
   formatting_range<Char> formatting;
 
   template <typename ParseContext>
-  FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
     return formatting.parse(ctx);
   }
 
   template <typename FormatContext>
-  typename FormatContext::iterator format(
-      const RangeT &values, FormatContext &ctx) {
-    auto out = ctx.out();
-    internal::copy(formatting.prefix, out);
-    std::size_t i = 0;
-    for (auto it = values.begin(), end = values.end(); it != end; ++it) {
+  typename FormatContext::iterator format(const T& values, FormatContext& ctx) {
+    auto out = detail::copy(formatting.prefix, ctx.out());
+    size_t i = 0;
+    auto it = values.begin();
+    auto end = values.end();
+    for (; it != end; ++it) {
       if (i > 0) {
-        if (formatting.add_prepostfix_space) {
-          *out++ = ' ';
-        }
-        internal::copy(formatting.delimiter, out);
+        if (formatting.add_prepostfix_space) *out++ = ' ';
+        out = detail::copy(formatting.delimiter, out);
       }
-      format_to(out,
-                internal::format_str_quoted(
-                    (formatting.add_delimiter_spaces && i > 0), *it),
-                *it);
+      out = format_to(out,
+                      detail::format_str_quoted(
+                          (formatting.add_delimiter_spaces && i > 0), *it),
+                      *it);
       if (++i > formatting.range_length_limit) {
-        format_to(out, " ... <other elements>");
+        out = format_to(out, " ... <other elements>");
         break;
       }
     }
-    if (formatting.add_prepostfix_space) {
-      *out++ = ' ';
-    }
-    internal::copy(formatting.postfix, out);
-    return ctx.out();
+    if (formatting.add_prepostfix_space) *out++ = ' ';
+    return detail::copy(formatting.postfix, out);
   }
 };
 
+template <typename Char, typename... T> struct tuple_arg_join : detail::view {
+  const std::tuple<T...>& tuple;
+  basic_string_view<Char> sep;
+
+  tuple_arg_join(const std::tuple<T...>& t, basic_string_view<Char> s)
+      : tuple{t}, sep{s} {}
+};
+
+template <typename Char, typename... T>
+struct formatter<tuple_arg_join<Char, T...>, Char> {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  typename FormatContext::iterator format(
+      const tuple_arg_join<Char, T...>& value, FormatContext& ctx) {
+    return format(value, ctx, detail::make_index_sequence<sizeof...(T)>{});
+  }
+
+ private:
+  template <typename FormatContext, size_t... N>
+  typename FormatContext::iterator format(
+      const tuple_arg_join<Char, T...>& value, FormatContext& ctx,
+      detail::index_sequence<N...>) {
+    return format_args(value, ctx, std::get<N>(value.tuple)...);
+  }
+
+  template <typename FormatContext>
+  typename FormatContext::iterator format_args(
+      const tuple_arg_join<Char, T...>&, FormatContext& ctx) {
+    // NOTE: for compilers that support C++17, this empty function instantiation
+    // can be replaced with a constexpr branch in the variadic overload.
+    return ctx.out();
+  }
+
+  template <typename FormatContext, typename Arg, typename... Args>
+  typename FormatContext::iterator format_args(
+      const tuple_arg_join<Char, T...>& value, FormatContext& ctx,
+      const Arg& arg, const Args&... args) {
+    using base = formatter<typename std::decay<Arg>::type, Char>;
+    auto out = ctx.out();
+    out = base{}.format(arg, ctx);
+    if (sizeof...(Args) > 0) {
+      out = std::copy(value.sep.begin(), value.sep.end(), out);
+      ctx.advance_to(out);
+      return format_args(value, ctx, args...);
+    }
+    return out;
+  }
+};
+
+/**
+  \rst
+  Returns an object that formats `tuple` with elements separated by `sep`.
+
+  **Example**::
+
+    std::tuple<int, char> t = {1, 'a'};
+    fmt::print("{}", fmt::join(t, ", "));
+    // Output: "1, a"
+  \endrst
+ */
+template <typename... T>
+FMT_CONSTEXPR tuple_arg_join<char, T...> join(const std::tuple<T...>& tuple,
+                                              string_view sep) {
+  return {tuple, sep};
+}
+
+template <typename... T>
+FMT_CONSTEXPR tuple_arg_join<wchar_t, T...> join(const std::tuple<T...>& tuple,
+                                                 wstring_view sep) {
+  return {tuple, sep};
+}
+
+/**
+  \rst
+  Returns an object that formats `initializer_list` with elements separated by
+  `sep`.
+
+  **Example**::
+
+    fmt::print("{}", fmt::join({1, 2, 3}, ", "));
+    // Output: "1, 2, 3"
+  \endrst
+ */
+template <typename T>
+arg_join<const T*, const T*, char> join(std::initializer_list<T> list,
+                                        string_view sep) {
+  return join(std::begin(list), std::end(list), sep);
+}
+
+template <typename T>
+arg_join<const T*, const T*, wchar_t> join(std::initializer_list<T> list,
+                                           wstring_view sep) {
+  return join(std::begin(list), std::end(list), sep);
+}
+
 FMT_END_NAMESPACE
 
-#endif // FMT_RANGES_H_
-
+#endif  // FMT_RANGES_H_

include/fmt/time.h

@@ -1,160 +0,0 @@
-// Formatting library for C++ - time formatting
-//
-// Copyright (c) 2012 - present, Victor Zverovich
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-#ifndef FMT_TIME_H_
-#define FMT_TIME_H_
-
-#include "format.h"
-#include <ctime>
-#include <locale>
-
-FMT_BEGIN_NAMESPACE
-
-// Prevents expansion of a preceding token as a function-style macro.
-// Usage: f FMT_NOMACRO()
-#define FMT_NOMACRO
-
-namespace internal{
-inline null<> localtime_r FMT_NOMACRO(...) { return null<>(); }
-inline null<> localtime_s(...) { return null<>(); }
-inline null<> gmtime_r(...) { return null<>(); }
-inline null<> gmtime_s(...) { return null<>(); }
-}  // namespace internal
-
-// Thread-safe replacement for std::localtime
-inline std::tm localtime(std::time_t time) {
-  struct dispatcher {
-    std::time_t time_;
-    std::tm tm_;
-
-    dispatcher(std::time_t t): time_(t) {}
-
-    bool run() {
-      using namespace fmt::internal;
-      return handle(localtime_r(&time_, &tm_));
-    }
-
-    bool handle(std::tm *tm) { return tm != FMT_NULL; }
-
-    bool handle(internal::null<>) {
-      using namespace fmt::internal;
-      return fallback(localtime_s(&tm_, &time_));
-    }
-
-    bool fallback(int res) { return res == 0; }
-
-#if !FMT_MSC_VER
-    bool fallback(internal::null<>) {
-      using namespace fmt::internal;
-      std::tm *tm = std::localtime(&time_);
-      if (tm) tm_ = *tm;
-      return tm != FMT_NULL;
-    }
-#endif
-  };
-  dispatcher lt(time);
-  // Too big time values may be unsupported.
-  if (!lt.run())
-    FMT_THROW(format_error("time_t value out of range"));
-  return lt.tm_;
-}
-
-// Thread-safe replacement for std::gmtime
-inline std::tm gmtime(std::time_t time) {
-  struct dispatcher {
-    std::time_t time_;
-    std::tm tm_;
-
-    dispatcher(std::time_t t): time_(t) {}
-
-    bool run() {
-      using namespace fmt::internal;
-      return handle(gmtime_r(&time_, &tm_));
-    }
-
-    bool handle(std::tm *tm) { return tm != FMT_NULL; }
-
-    bool handle(internal::null<>) {
-      using namespace fmt::internal;
-      return fallback(gmtime_s(&tm_, &time_));
-    }
-
-    bool fallback(int res) { return res == 0; }
-
-#if !FMT_MSC_VER
-    bool fallback(internal::null<>) {
-      std::tm *tm = std::gmtime(&time_);
-      if (tm) tm_ = *tm;
-      return tm != FMT_NULL;
-    }
-#endif
-  };
-  dispatcher gt(time);
-  // Too big time values may be unsupported.
-  if (!gt.run())
-    FMT_THROW(format_error("time_t value out of range"));
-  return gt.tm_;
-}
-
-namespace internal {
-inline std::size_t strftime(char *str, std::size_t count, const char *format,
-                            const std::tm *time) {
-  return std::strftime(str, count, format, time);
-}
-
-inline std::size_t strftime(wchar_t *str, std::size_t count,
-                            const wchar_t *format, const std::tm *time) {
-  return std::wcsftime(str, count, format, time);
-}
-}
-
-template <typename Char>
-struct formatter<std::tm, Char> {
-  template <typename ParseContext>
-  auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
-    auto it = ctx.begin();
-    if (it != ctx.end() && *it == ':')
-      ++it;
-    auto end = it;
-    while (end != ctx.end() && *end != '}')
-      ++end;
-    tm_format.reserve(internal::to_unsigned(end - it + 1));
-    tm_format.append(it, end);
-    tm_format.push_back('\0');
-    return end;
-  }
-
-  template <typename FormatContext>
-  auto format(const std::tm &tm, FormatContext &ctx) -> decltype(ctx.out()) {
-    basic_memory_buffer<Char> buf;
-    std::size_t start = buf.size();
-    for (;;) {
-      std::size_t size = buf.capacity() - start;
-      std::size_t count =
-        internal::strftime(&buf[start], size, &tm_format[0], &tm);
-      if (count != 0) {
-        buf.resize(start + count);
-        break;
-      }
-      if (size >= tm_format.size() * 256) {
-        // If the buffer is 256 times larger than the format string, assume
-        // that `strftime` gives an empty result. There doesn't seem to be a
-        // better way to distinguish the two cases:
-        // https://github.com/fmtlib/fmt/issues/367
-        break;
-      }
-      const std::size_t MIN_GROWTH = 10;
-      buf.reserve(buf.capacity() + (size > MIN_GROWTH ? size : MIN_GROWTH));
-    }
-    return std::copy(buf.begin(), buf.end(), ctx.out());
-  }
-
-  basic_memory_buffer<Char> tm_format;
-};
-FMT_END_NAMESPACE
-
-#endif  // FMT_TIME_H_

pull_request_template.md

@@ -0,0 +1,6 @@
+<!-- Please read the contribution guidelines before submitting a pull request. -->
+<!-- By submitting this pull request, you agree that your contributions are licensed under the {fmt} license,
+     and agree to future changes to the licensing. -->
+<!-- If you're a first-time contributor, please acknowledge it by leaving the statement below. -->
+
+I agree that my contributions are licensed under the {fmt} license, and agree to future changes to the licensing.

src/format.cc

@@ -8,52 +8,92 @@
 #include "fmt/format-inl.h"
 
 FMT_BEGIN_NAMESPACE
-template struct internal::basic_data<void>;
-template FMT_API internal::locale_ref::locale_ref(const std::locale &loc);
-template FMT_API std::locale internal::locale_ref::get<std::locale>() const;
+namespace detail {
+
+template <typename T>
+int format_float(char* buf, std::size_t size, const char* format, int precision,
+                 T value) {
+#ifdef FMT_FUZZ
+  if (precision > 100000)
+    throw std::runtime_error(
+        "fuzz mode - avoid large allocation inside snprintf");
+#endif
+  // Suppress the warning about nonliteral format string.
+  int (*snprintf_ptr)(char*, size_t, const char*, ...) = FMT_SNPRINTF;
+  return precision < 0 ? snprintf_ptr(buf, size, format, value)
+                       : snprintf_ptr(buf, size, format, precision, value);
+}
+
+template dragonbox::decimal_fp<float> dragonbox::to_decimal(float x)
+    FMT_NOEXCEPT;
+template dragonbox::decimal_fp<double> dragonbox::to_decimal(double x)
+    FMT_NOEXCEPT;
+
+// DEPRECATED! This function exists for ABI compatibility.
+template <typename Char>
+typename basic_format_context<std::back_insert_iterator<buffer<Char>>,
+                              Char>::iterator
+vformat_to(buffer<Char>& buf, basic_string_view<Char> format_str,
+           basic_format_args<basic_format_context<
+               std::back_insert_iterator<buffer<type_identity_t<Char>>>,
+               type_identity_t<Char>>>
+               args) {
+  using iterator = std::back_insert_iterator<buffer<char>>;
+  using context = basic_format_context<
+      std::back_insert_iterator<buffer<type_identity_t<Char>>>,
+      type_identity_t<Char>>;
+  auto out = iterator(buf);
+  format_handler<iterator, Char, context> h(out, format_str, args, {});
+  parse_format_string<false>(format_str, h);
+  return out;
+}
+template basic_format_context<std::back_insert_iterator<buffer<char>>,
+                              char>::iterator
+vformat_to(buffer<char>&, string_view,
+           basic_format_args<basic_format_context<
+               std::back_insert_iterator<buffer<type_identity_t<char>>>,
+               type_identity_t<char>>>);
+}  // namespace detail
+
+template struct FMT_INSTANTIATION_DEF_API detail::basic_data<void>;
+
+// Workaround a bug in MSVC2013 that prevents instantiation of format_float.
+int (*instantiate_format_float)(double, int, detail::float_specs,
+                                detail::buffer<char>&) = detail::format_float;
+
+#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
+template FMT_API detail::locale_ref::locale_ref(const std::locale& loc);
+template FMT_API std::locale detail::locale_ref::get<std::locale>() const;
+#endif
 
 // Explicit instantiations for char.
 
-template FMT_API char internal::thousands_sep_impl(locale_ref);
+template FMT_API std::string detail::grouping_impl<char>(locale_ref);
+template FMT_API char detail::thousands_sep_impl(locale_ref);
+template FMT_API char detail::decimal_point_impl(locale_ref);
 
-template FMT_API void internal::basic_buffer<char>::append(const char *, const char *);
+template FMT_API void detail::buffer<char>::append(const char*, const char*);
 
-template FMT_API void internal::arg_map<format_context>::init(
-    const basic_format_args<format_context> &args);
+template FMT_API void detail::vformat_to(
+    detail::buffer<char>&, string_view,
+    basic_format_args<FMT_BUFFER_CONTEXT(char)>, detail::locale_ref);
 
-template FMT_API int internal::char_traits<char>::format_float(
-    char *, std::size_t, const char *, int, double);
-
-template FMT_API int internal::char_traits<char>::format_float(
-    char *, std::size_t, const char *, int, long double);
-
-template FMT_API std::string internal::vformat<char>(
-    string_view, basic_format_args<format_context>);
-
-template FMT_API format_context::iterator internal::vformat_to(
-    internal::buffer &, string_view, basic_format_args<format_context>);
-
-template FMT_API void internal::sprintf_format(
-    double, internal::buffer &, core_format_specs);
-template FMT_API void internal::sprintf_format(
-    long double, internal::buffer &, core_format_specs);
+template FMT_API int detail::snprintf_float(double, int, detail::float_specs,
+                                            detail::buffer<char>&);
+template FMT_API int detail::snprintf_float(long double, int,
+                                            detail::float_specs,
+                                            detail::buffer<char>&);
+template FMT_API int detail::format_float(double, int, detail::float_specs,
+                                          detail::buffer<char>&);
+template FMT_API int detail::format_float(long double, int, detail::float_specs,
+                                          detail::buffer<char>&);
 
 // Explicit instantiations for wchar_t.
 
-template FMT_API wchar_t internal::thousands_sep_impl(locale_ref);
+template FMT_API std::string detail::grouping_impl<wchar_t>(locale_ref);
+template FMT_API wchar_t detail::thousands_sep_impl(locale_ref);
+template FMT_API wchar_t detail::decimal_point_impl(locale_ref);
 
-template FMT_API void internal::basic_buffer<wchar_t>::append(
-    const wchar_t *, const wchar_t *);
-
-template FMT_API void internal::arg_map<wformat_context>::init(
-    const basic_format_args<wformat_context> &);
-
-template FMT_API int internal::char_traits<wchar_t>::format_float(
-    wchar_t *, std::size_t, const wchar_t *, int, double);
-
-template FMT_API int internal::char_traits<wchar_t>::format_float(
-    wchar_t *, std::size_t, const wchar_t *, int, long double);
-
-template FMT_API std::wstring internal::vformat<wchar_t>(
-    wstring_view, basic_format_args<wformat_context>);
+template FMT_API void detail::buffer<wchar_t>::append(const wchar_t*,
+                                                      const wchar_t*);
 FMT_END_NAMESPACE

src/os.cc

@@ -0,0 +1,322 @@
+// Formatting library for C++ - optional OS-specific functionality
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+// Disable bogus MSVC warnings.
+#if !defined(_CRT_SECURE_NO_WARNINGS) && defined(_MSC_VER)
+#  define _CRT_SECURE_NO_WARNINGS
+#endif
+
+#include "fmt/os.h"
+
+#include <climits>
+
+#if FMT_USE_FCNTL
+#  include <sys/stat.h>
+#  include <sys/types.h>
+
+#  ifndef _WIN32
+#    include <unistd.h>
+#  else
+#    ifndef WIN32_LEAN_AND_MEAN
+#      define WIN32_LEAN_AND_MEAN
+#    endif
+#    include <io.h>
+#    include <windows.h>
+
+#    define O_CREAT _O_CREAT
+#    define O_TRUNC _O_TRUNC
+
+#    ifndef S_IRUSR
+#      define S_IRUSR _S_IREAD
+#    endif
+
+#    ifndef S_IWUSR
+#      define S_IWUSR _S_IWRITE
+#    endif
+
+#    ifdef __MINGW32__
+#      define _SH_DENYNO 0x40
+#    endif
+#  endif  // _WIN32
+#endif    // FMT_USE_FCNTL
+
+#ifdef _WIN32
+#  include <windows.h>
+#endif
+
+#ifdef fileno
+#  undef fileno
+#endif
+
+namespace {
+#ifdef _WIN32
+// Return type of read and write functions.
+using RWResult = int;
+
+// On Windows the count argument to read and write is unsigned, so convert
+// it from size_t preventing integer overflow.
+inline unsigned convert_rwcount(std::size_t count) {
+  return count <= UINT_MAX ? static_cast<unsigned>(count) : UINT_MAX;
+}
+#elif FMT_USE_FCNTL
+// Return type of read and write functions.
+using RWResult = ssize_t;
+
+inline std::size_t convert_rwcount(std::size_t count) { return count; }
+#endif
+}  // namespace
+
+FMT_BEGIN_NAMESPACE
+
+#ifdef _WIN32
+detail::utf16_to_utf8::utf16_to_utf8(wstring_view s) {
+  if (int error_code = convert(s)) {
+    FMT_THROW(windows_error(error_code,
+                            "cannot convert string from UTF-16 to UTF-8"));
+  }
+}
+
+int detail::utf16_to_utf8::convert(wstring_view s) {
+  if (s.size() > INT_MAX) return ERROR_INVALID_PARAMETER;
+  int s_size = static_cast<int>(s.size());
+  if (s_size == 0) {
+    // WideCharToMultiByte does not support zero length, handle separately.
+    buffer_.resize(1);
+    buffer_[0] = 0;
+    return 0;
+  }
+
+  int length = WideCharToMultiByte(CP_UTF8, 0, s.data(), s_size, nullptr, 0,
+                                   nullptr, nullptr);
+  if (length == 0) return GetLastError();
+  buffer_.resize(length + 1);
+  length = WideCharToMultiByte(CP_UTF8, 0, s.data(), s_size, &buffer_[0],
+                               length, nullptr, nullptr);
+  if (length == 0) return GetLastError();
+  buffer_[length] = 0;
+  return 0;
+}
+
+void windows_error::init(int err_code, string_view format_str,
+                         format_args args) {
+  error_code_ = err_code;
+  memory_buffer buffer;
+  detail::format_windows_error(buffer, err_code, vformat(format_str, args));
+  std::runtime_error& base = *this;
+  base = std::runtime_error(to_string(buffer));
+}
+
+void detail::format_windows_error(detail::buffer<char>& out, int error_code,
+                                  string_view message) FMT_NOEXCEPT {
+  FMT_TRY {
+    wmemory_buffer buf;
+    buf.resize(inline_buffer_size);
+    for (;;) {
+      wchar_t* system_message = &buf[0];
+      int result = FormatMessageW(
+          FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, nullptr,
+          error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), system_message,
+          static_cast<uint32_t>(buf.size()), nullptr);
+      if (result != 0) {
+        utf16_to_utf8 utf8_message;
+        if (utf8_message.convert(system_message) == ERROR_SUCCESS) {
+          format_to(buffer_appender<char>(out), "{}: {}", message,
+                    utf8_message);
+          return;
+        }
+        break;
+      }
+      if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
+        break;  // Can't get error message, report error code instead.
+      buf.resize(buf.size() * 2);
+    }
+  }
+  FMT_CATCH(...) {}
+  format_error_code(out, error_code, message);
+}
+
+void report_windows_error(int error_code,
+                          fmt::string_view message) FMT_NOEXCEPT {
+  report_error(detail::format_windows_error, error_code, message);
+}
+#endif  // _WIN32
+
+buffered_file::~buffered_file() FMT_NOEXCEPT {
+  if (file_ && FMT_SYSTEM(fclose(file_)) != 0)
+    report_system_error(errno, "cannot close file");
+}
+
+buffered_file::buffered_file(cstring_view filename, cstring_view mode) {
+  FMT_RETRY_VAL(file_, FMT_SYSTEM(fopen(filename.c_str(), mode.c_str())),
+                nullptr);
+  if (!file_)
+    FMT_THROW(system_error(errno, "cannot open file {}", filename.c_str()));
+}
+
+void buffered_file::close() {
+  if (!file_) return;
+  int result = FMT_SYSTEM(fclose(file_));
+  file_ = nullptr;
+  if (result != 0) FMT_THROW(system_error(errno, "cannot close file"));
+}
+
+// A macro used to prevent expansion of fileno on broken versions of MinGW.
+#define FMT_ARGS
+
+int buffered_file::fileno() const {
+  int fd = FMT_POSIX_CALL(fileno FMT_ARGS(file_));
+  if (fd == -1) FMT_THROW(system_error(errno, "cannot get file descriptor"));
+  return fd;
+}
+
+#if FMT_USE_FCNTL
+file::file(cstring_view path, int oflag) {
+  int mode = S_IRUSR | S_IWUSR;
+#  if defined(_WIN32) && !defined(__MINGW32__)
+  fd_ = -1;
+  FMT_POSIX_CALL(sopen_s(&fd_, path.c_str(), oflag, _SH_DENYNO, mode));
+#  else
+  FMT_RETRY(fd_, FMT_POSIX_CALL(open(path.c_str(), oflag, mode)));
+#  endif
+  if (fd_ == -1)
+    FMT_THROW(system_error(errno, "cannot open file {}", path.c_str()));
+}
+
+file::~file() FMT_NOEXCEPT {
+  // Don't retry close in case of EINTR!
+  // See http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-09/3000.html
+  if (fd_ != -1 && FMT_POSIX_CALL(close(fd_)) != 0)
+    report_system_error(errno, "cannot close file");
+}
+
+void file::close() {
+  if (fd_ == -1) return;
+  // Don't retry close in case of EINTR!
+  // See http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-09/3000.html
+  int result = FMT_POSIX_CALL(close(fd_));
+  fd_ = -1;
+  if (result != 0) FMT_THROW(system_error(errno, "cannot close file"));
+}
+
+long long file::size() const {
+#  ifdef _WIN32
+  // Use GetFileSize instead of GetFileSizeEx for the case when _WIN32_WINNT
+  // is less than 0x0500 as is the case with some default MinGW builds.
+  // Both functions support large file sizes.
+  DWORD size_upper = 0;
+  HANDLE handle = reinterpret_cast<HANDLE>(_get_osfhandle(fd_));
+  DWORD size_lower = FMT_SYSTEM(GetFileSize(handle, &size_upper));
+  if (size_lower == INVALID_FILE_SIZE) {
+    DWORD error = GetLastError();
+    if (error != NO_ERROR)
+      FMT_THROW(windows_error(GetLastError(), "cannot get file size"));
+  }
+  unsigned long long long_size = size_upper;
+  return (long_size << sizeof(DWORD) * CHAR_BIT) | size_lower;
+#  else
+  using Stat = struct stat;
+  Stat file_stat = Stat();
+  if (FMT_POSIX_CALL(fstat(fd_, &file_stat)) == -1)
+    FMT_THROW(system_error(errno, "cannot get file attributes"));
+  static_assert(sizeof(long long) >= sizeof(file_stat.st_size),
+                "return type of file::size is not large enough");
+  return file_stat.st_size;
+#  endif
+}
+
+std::size_t file::read(void* buffer, std::size_t count) {
+  RWResult result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(read(fd_, buffer, convert_rwcount(count))));
+  if (result < 0) FMT_THROW(system_error(errno, "cannot read from file"));
+  return detail::to_unsigned(result);
+}
+
+std::size_t file::write(const void* buffer, std::size_t count) {
+  RWResult result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(write(fd_, buffer, convert_rwcount(count))));
+  if (result < 0) FMT_THROW(system_error(errno, "cannot write to file"));
+  return detail::to_unsigned(result);
+}
+
+file file::dup(int fd) {
+  // Don't retry as dup doesn't return EINTR.
+  // http://pubs.opengroup.org/onlinepubs/009695399/functions/dup.html
+  int new_fd = FMT_POSIX_CALL(dup(fd));
+  if (new_fd == -1)
+    FMT_THROW(system_error(errno, "cannot duplicate file descriptor {}", fd));
+  return file(new_fd);
+}
+
+void file::dup2(int fd) {
+  int result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(dup2(fd_, fd)));
+  if (result == -1) {
+    FMT_THROW(system_error(errno, "cannot duplicate file descriptor {} to {}",
+                           fd_, fd));
+  }
+}
+
+void file::dup2(int fd, error_code& ec) FMT_NOEXCEPT {
+  int result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(dup2(fd_, fd)));
+  if (result == -1) ec = error_code(errno);
+}
+
+void file::pipe(file& read_end, file& write_end) {
+  // Close the descriptors first to make sure that assignments don't throw
+  // and there are no leaks.
+  read_end.close();
+  write_end.close();
+  int fds[2] = {};
+#  ifdef _WIN32
+  // Make the default pipe capacity same as on Linux 2.6.11+.
+  enum { DEFAULT_CAPACITY = 65536 };
+  int result = FMT_POSIX_CALL(pipe(fds, DEFAULT_CAPACITY, _O_BINARY));
+#  else
+  // Don't retry as the pipe function doesn't return EINTR.
+  // http://pubs.opengroup.org/onlinepubs/009696799/functions/pipe.html
+  int result = FMT_POSIX_CALL(pipe(fds));
+#  endif
+  if (result != 0) FMT_THROW(system_error(errno, "cannot create pipe"));
+  // The following assignments don't throw because read_fd and write_fd
+  // are closed.
+  read_end = file(fds[0]);
+  write_end = file(fds[1]);
+}
+
+buffered_file file::fdopen(const char* mode) {
+// Don't retry as fdopen doesn't return EINTR.
+#  if defined(__MINGW32__) && defined(_POSIX_)
+  FILE* f = ::fdopen(fd_, mode);
+#  else
+  FILE* f = FMT_POSIX_CALL(fdopen(fd_, mode));
+#  endif
+  if (!f)
+    FMT_THROW(
+        system_error(errno, "cannot associate stream with file descriptor"));
+  buffered_file bf(f);
+  fd_ = -1;
+  return bf;
+}
+
+long getpagesize() {
+#  ifdef _WIN32
+  SYSTEM_INFO si;
+  GetSystemInfo(&si);
+  return si.dwPageSize;
+#  else
+  long size = FMT_POSIX_CALL(sysconf(_SC_PAGESIZE));
+  if (size < 0) FMT_THROW(system_error(errno, "cannot get memory page size"));
+  return size;
+#  endif
+}
+
+void ostream::grow(size_t) {
+  if (this->size() == this->capacity()) flush();
+}
+#endif  // FMT_USE_FCNTL
+FMT_END_NAMESPACE

src/posix.cc

@@ -1,244 +0,0 @@
-// A C++ interface to POSIX functions.
-//
-// Copyright (c) 2012 - 2016, Victor Zverovich
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-// Disable bogus MSVC warnings.
-#if !defined(_CRT_SECURE_NO_WARNINGS) && defined(_MSC_VER)
-# define _CRT_SECURE_NO_WARNINGS
-#endif
-
-#include "fmt/posix.h"
-
-#include <limits.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-
-#ifndef _WIN32
-# include <unistd.h>
-#else
-# ifndef WIN32_LEAN_AND_MEAN
-#  define WIN32_LEAN_AND_MEAN
-# endif
-# include <windows.h>
-# include <io.h>
-
-# define O_CREAT _O_CREAT
-# define O_TRUNC _O_TRUNC
-
-# ifndef S_IRUSR
-#  define S_IRUSR _S_IREAD
-# endif
-
-# ifndef S_IWUSR
-#  define S_IWUSR _S_IWRITE
-# endif
-
-# ifdef __MINGW32__
-#  define _SH_DENYNO 0x40
-# endif
-
-#endif  // _WIN32
-
-#ifdef fileno
-# undef fileno
-#endif
-
-namespace {
-#ifdef _WIN32
-// Return type of read and write functions.
-typedef int RWResult;
-
-// On Windows the count argument to read and write is unsigned, so convert
-// it from size_t preventing integer overflow.
-inline unsigned convert_rwcount(std::size_t count) {
-  return count <= UINT_MAX ? static_cast<unsigned>(count) : UINT_MAX;
-}
-#else
-// Return type of read and write functions.
-typedef ssize_t RWResult;
-
-inline std::size_t convert_rwcount(std::size_t count) { return count; }
-#endif
-}
-
-FMT_BEGIN_NAMESPACE
-
-buffered_file::~buffered_file() FMT_NOEXCEPT {
-  if (file_ && FMT_SYSTEM(fclose(file_)) != 0)
-    report_system_error(errno, "cannot close file");
-}
-
-buffered_file::buffered_file(cstring_view filename, cstring_view mode) {
-  FMT_RETRY_VAL(file_,
-                FMT_SYSTEM(fopen(filename.c_str(), mode.c_str())), FMT_NULL);
-  if (!file_)
-    FMT_THROW(system_error(errno, "cannot open file {}", filename.c_str()));
-}
-
-void buffered_file::close() {
-  if (!file_)
-    return;
-  int result = FMT_SYSTEM(fclose(file_));
-  file_ = FMT_NULL;
-  if (result != 0)
-    FMT_THROW(system_error(errno, "cannot close file"));
-}
-
-// A macro used to prevent expansion of fileno on broken versions of MinGW.
-#define FMT_ARGS
-
-int buffered_file::fileno() const {
-  int fd = FMT_POSIX_CALL(fileno FMT_ARGS(file_));
-  if (fd == -1)
-    FMT_THROW(system_error(errno, "cannot get file descriptor"));
-  return fd;
-}
-
-file::file(cstring_view path, int oflag) {
-  int mode = S_IRUSR | S_IWUSR;
-#if defined(_WIN32) && !defined(__MINGW32__)
-  fd_ = -1;
-  FMT_POSIX_CALL(sopen_s(&fd_, path.c_str(), oflag, _SH_DENYNO, mode));
-#else
-  FMT_RETRY(fd_, FMT_POSIX_CALL(open(path.c_str(), oflag, mode)));
-#endif
-  if (fd_ == -1)
-    FMT_THROW(system_error(errno, "cannot open file {}", path.c_str()));
-}
-
-file::~file() FMT_NOEXCEPT {
-  // Don't retry close in case of EINTR!
-  // See http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-09/3000.html
-  if (fd_ != -1 && FMT_POSIX_CALL(close(fd_)) != 0)
-    report_system_error(errno, "cannot close file");
-}
-
-void file::close() {
-  if (fd_ == -1)
-    return;
-  // Don't retry close in case of EINTR!
-  // See http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-09/3000.html
-  int result = FMT_POSIX_CALL(close(fd_));
-  fd_ = -1;
-  if (result != 0)
-    FMT_THROW(system_error(errno, "cannot close file"));
-}
-
-long long file::size() const {
-#ifdef _WIN32
-  // Use GetFileSize instead of GetFileSizeEx for the case when _WIN32_WINNT
-  // is less than 0x0500 as is the case with some default MinGW builds.
-  // Both functions support large file sizes.
-  DWORD size_upper = 0;
-  HANDLE handle = reinterpret_cast<HANDLE>(_get_osfhandle(fd_));
-  DWORD size_lower = FMT_SYSTEM(GetFileSize(handle, &size_upper));
-  if (size_lower == INVALID_FILE_SIZE) {
-    DWORD error = GetLastError();
-    if (error != NO_ERROR)
-      FMT_THROW(windows_error(GetLastError(), "cannot get file size"));
-  }
-  unsigned long long long_size = size_upper;
-  return (long_size << sizeof(DWORD) * CHAR_BIT) | size_lower;
-#else
-  typedef struct stat Stat;
-  Stat file_stat = Stat();
-  if (FMT_POSIX_CALL(fstat(fd_, &file_stat)) == -1)
-    FMT_THROW(system_error(errno, "cannot get file attributes"));
-  static_assert(sizeof(long long) >= sizeof(file_stat.st_size),
-      "return type of file::size is not large enough");
-  return file_stat.st_size;
-#endif
-}
-
-std::size_t file::read(void *buffer, std::size_t count) {
-  RWResult result = 0;
-  FMT_RETRY(result, FMT_POSIX_CALL(read(fd_, buffer, convert_rwcount(count))));
-  if (result < 0)
-    FMT_THROW(system_error(errno, "cannot read from file"));
-  return internal::to_unsigned(result);
-}
-
-std::size_t file::write(const void *buffer, std::size_t count) {
-  RWResult result = 0;
-  FMT_RETRY(result, FMT_POSIX_CALL(write(fd_, buffer, convert_rwcount(count))));
-  if (result < 0)
-    FMT_THROW(system_error(errno, "cannot write to file"));
-  return internal::to_unsigned(result);
-}
-
-file file::dup(int fd) {
-  // Don't retry as dup doesn't return EINTR.
-  // http://pubs.opengroup.org/onlinepubs/009695399/functions/dup.html
-  int new_fd = FMT_POSIX_CALL(dup(fd));
-  if (new_fd == -1)
-    FMT_THROW(system_error(errno, "cannot duplicate file descriptor {}", fd));
-  return file(new_fd);
-}
-
-void file::dup2(int fd) {
-  int result = 0;
-  FMT_RETRY(result, FMT_POSIX_CALL(dup2(fd_, fd)));
-  if (result == -1) {
-    FMT_THROW(system_error(errno,
-      "cannot duplicate file descriptor {} to {}", fd_, fd));
-  }
-}
-
-void file::dup2(int fd, error_code &ec) FMT_NOEXCEPT {
-  int result = 0;
-  FMT_RETRY(result, FMT_POSIX_CALL(dup2(fd_, fd)));
-  if (result == -1)
-    ec = error_code(errno);
-}
-
-void file::pipe(file &read_end, file &write_end) {
-  // Close the descriptors first to make sure that assignments don't throw
-  // and there are no leaks.
-  read_end.close();
-  write_end.close();
-  int fds[2] = {};
-#ifdef _WIN32
-  // Make the default pipe capacity same as on Linux 2.6.11+.
-  enum { DEFAULT_CAPACITY = 65536 };
-  int result = FMT_POSIX_CALL(pipe(fds, DEFAULT_CAPACITY, _O_BINARY));
-#else
-  // Don't retry as the pipe function doesn't return EINTR.
-  // http://pubs.opengroup.org/onlinepubs/009696799/functions/pipe.html
-  int result = FMT_POSIX_CALL(pipe(fds));
-#endif
-  if (result != 0)
-    FMT_THROW(system_error(errno, "cannot create pipe"));
-  // The following assignments don't throw because read_fd and write_fd
-  // are closed.
-  read_end = file(fds[0]);
-  write_end = file(fds[1]);
-}
-
-buffered_file file::fdopen(const char *mode) {
-  // Don't retry as fdopen doesn't return EINTR.
-  FILE *f = FMT_POSIX_CALL(fdopen(fd_, mode));
-  if (!f)
-    FMT_THROW(system_error(errno,
-                           "cannot associate stream with file descriptor"));
-  buffered_file bf(f);
-  fd_ = -1;
-  return bf;
-}
-
-long getpagesize() {
-#ifdef _WIN32
-  SYSTEM_INFO si;
-  GetSystemInfo(&si);
-  return si.dwPageSize;
-#else
-  long size = FMT_POSIX_CALL(sysconf(_SC_PAGESIZE));
-  if (size < 0)
-    FMT_THROW(system_error(errno, "cannot get memory page size"));
-  return size;
-#endif
-}
-FMT_END_NAMESPACE
-

support/README

@@ -2,5 +2,3 @@ This directory contains build support files such as
 
 * CMake modules
 * Build scripts
-* qmake (static build with dynamic libc only)
-

support/Vagrantfile

@@ -0,0 +1,20 @@
+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+# A vagrant config for testing against gcc-4.8.
+Vagrant.configure("2") do |config|
+  config.vm.box = "ubuntu/xenial64"
+  config.disksize.size = '15GB'
+
+  config.vm.provider "virtualbox" do |vb|
+    vb.memory = "4096"
+  end
+
+  config.vm.provision "shell", inline: <<-SHELL
+    apt-get update
+    apt-get install -y g++ make wget git
+    wget -q https://github.com/Kitware/CMake/releases/download/v3.14.4/cmake-3.14.4-Linux-x86_64.tar.gz
+    tar xzf cmake-3.14.4-Linux-x86_64.tar.gz
+    ln -s `pwd`/cmake-3.14.4-Linux-x86_64/bin/cmake /usr/local/bin
+  SHELL
+end

support/appveyor-build.py

@@ -23,14 +23,17 @@ else:
     # Add MSBuild 14.0 to PATH as described in
     # http://help.appveyor.com/discussions/problems/2229-v140-not-found-on-vs2105rc.
     os.environ['PATH'] = r'C:\Program Files (x86)\MSBuild\15.0\Bin;' + path
-    if image == 'Visual Studio 2013':
-        generator = 'Visual Studio 12 2013'
-    elif image == 'Visual Studio 2015':
-        generator = 'Visual Studio 14 2015'
-    elif image == 'Visual Studio 2017':
-        generator = 'Visual Studio 15 2017'
-    if platform == 'x64':
-        generator += ' Win64'
+    if image == 'Visual Studio 2019':
+        generator = 'Visual Studio 16 2019'
+        if platform == 'x64':
+            cmake_command.extend(['-A', 'x64'])
+    else:
+        if image == 'Visual Studio 2015':
+            generator = 'Visual Studio 14 2015'
+        elif image == 'Visual Studio 2017':
+            generator = 'Visual Studio 15 2017'
+        if platform == 'x64':
+            generator += ' Win64'
     cmake_command.append('-G' + generator)
     build_command = ['cmake', '--build', '.', '--config', config, '--', '/m:4']
     test_command = ['ctest', '-C', config]

support/appveyor.yml

@@ -4,20 +4,27 @@ configuration:
 
 clone_depth: 1
 
+image:
+  - Visual Studio 2015
+  - Visual Studio 2019
+  - Visual Studio 2017
+
 platform:
   - Win32
   - x64
 
-image:
-  - Visual Studio 2013
-  - Visual Studio 2015
-  - Visual Studio 2017
-
 environment:
   CTEST_OUTPUT_ON_FAILURE: 1
   MSVC_DEFAULT_OPTIONS: ON
   BUILD: msvc
 
+matrix:
+  exclude:
+    - image: Visual Studio 2015
+      platform: Win32
+    - image: Visual Studio 2019
+      platform: Win32
+
 before_build:
  - mkdir build
  - cd build

support/build.gradle

@@ -9,10 +9,12 @@ buildscript {
         //
         // https://developer.android.com/studio/releases/gradle-plugin
         //
-        // Notice that 3.1.3 here is the version of [Android Gradle Plugin]
-        // Accroding to URL above you will need Gradle 4.4 or higher
+        // Notice that 3.3.0 here is the version of [Android Gradle Plugin]
+        // Accroding to URL above you will need Gradle 5.0 or higher
         //
-        classpath 'com.android.tools.build:gradle:3.1.3'
+        // If you are using Android Studio, and it is using Gradle's lower 
+        // version, Use the plugin version 3.1.3 ~ 3.2.0 for Gradle 4.4 ~ 4.10
+        classpath 'com.android.tools.build:gradle:3.3.0'
     }
 }
 repositories {
@@ -43,8 +45,8 @@ android {
     defaultConfig {
         minSdkVersion 21    // Android 5.0+
         targetSdkVersion 25 // Follow Compile SDK
-        versionCode 20      // Follow release count
-        versionName "5.2.1" // Follow Official version
+        versionCode 21      // Follow release count
+        versionName "5.3.0" // Follow Official version
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         
         externalNativeBuild {

support/cmake/JoinPaths.cmake

@@ -0,0 +1,26 @@
+# This module provides function for joining paths
+# known from from most languages
+#
+# Original license:
+# SPDX-License-Identifier: (MIT OR CC0-1.0)
+# Explicit permission given to distribute this module under
+# the terms of the project as described in /LICENSE.rst.
+# Copyright 2020 Jan Tojnar
+# https://github.com/jtojnar/cmake-snips
+#
+# Modelled after Python’s os.path.join
+# https://docs.python.org/3.7/library/os.path.html#os.path.join
+# Windows not supported
+function(join_paths joined_path first_path_segment)
+    set(temp_path "${first_path_segment}")
+    foreach(current_segment IN LISTS ARGN)
+        if(NOT ("${current_segment}" STREQUAL ""))
+            if(IS_ABSOLUTE "${current_segment}")
+                set(temp_path "${current_segment}")
+            else()
+                set(temp_path "${temp_path}/${current_segment}")
+            endif()
+        endif()
+    endforeach()
+    set(${joined_path} "${temp_path}" PARENT_SCOPE)
+endfunction()

support/cmake/cxx14.cmake

@@ -48,43 +48,6 @@ endif ()
 
 set(CMAKE_REQUIRED_FLAGS ${CXX_STANDARD_FLAG})
 
-# Check if variadic templates are working and not affected by GCC bug 39653:
-# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=39653
-check_cxx_source_compiles("
-  template <class T, class ...Types>
-  struct S { typedef typename S<Types...>::type type; };
-  int main() {}" SUPPORTS_VARIADIC_TEMPLATES)
-if (NOT SUPPORTS_VARIADIC_TEMPLATES)
-  set (SUPPORTS_VARIADIC_TEMPLATES OFF)
-endif ()
-
-# Check if initializer lists are supported.
-check_cxx_source_compiles("
-  #include <initializer_list>
-  int main() {}" SUPPORTS_INITIALIZER_LIST)
-if (NOT SUPPORTS_INITIALIZER_LIST)
-  set (SUPPORTS_INITIALIZER_LIST OFF)
-endif ()
-
-# Check if enum bases are available
-check_cxx_source_compiles("
-  enum C : char {A};
-  int main() {}"
-  SUPPORTS_ENUM_BASE)
-if (NOT SUPPORTS_ENUM_BASE)
-  set (SUPPORTS_ENUM_BASE OFF)
-endif ()
-
-# Check if type traits are available
-check_cxx_source_compiles("
-  #include <type_traits>
-  class C { void operator=(const C&); };
-  int main() { static_assert(!std::is_copy_assignable<C>::value, \"\"); }"
-  SUPPORTS_TYPE_TRAITS)
-if (NOT SUPPORTS_TYPE_TRAITS)
-  set (SUPPORTS_TYPE_TRAITS OFF)
-endif ()
-
 # Check if user-defined literals are available
 check_cxx_source_compiles("
   void operator\"\" _udl(long double);
@@ -94,4 +57,14 @@ if (NOT SUPPORTS_USER_DEFINED_LITERALS)
   set (SUPPORTS_USER_DEFINED_LITERALS OFF)
 endif ()
 
+# Check if <variant> is available
+set(CMAKE_REQUIRED_FLAGS -std=c++1z)
+check_cxx_source_compiles("
+  #include <variant>
+  int main() {}"
+  FMT_HAS_VARIANT)
+if (NOT FMT_HAS_VARIANT)
+  set (FMT_HAS_VARIANT OFF)
+endif ()
+
 set(CMAKE_REQUIRED_FLAGS )

support/cmake/fmt.pc.in

@@ -1,11 +1,11 @@
 prefix=@CMAKE_INSTALL_PREFIX@
 exec_prefix=@CMAKE_INSTALL_PREFIX@
-libdir=@CMAKE_INSTALL_FULL_LIBDIR@
-includedir=@CMAKE_INSTALL_FULL_INCLUDEDIR@
+libdir=@libdir_for_pc_file@
+includedir=@includedir_for_pc_file@
 
 Name: fmt
 Description: A modern formatting library
 Version: @FMT_VERSION@
-Libs: -L${libdir} -lfmt
+Libs: -L${libdir} -l@FMT_LIB_NAME@
 Cflags: -I${includedir}
 

support/cmake/run-cmake.bat

@@ -1,11 +0,0 @@
-@echo on
-rem This scripts configures build environment and runs CMake.
-rem Use it instead of running CMake directly when building with
-rem the Microsoft SDK toolchain rather than Visual Studio.
-rem It is used in the same way as cmake, for example:
-rem
-rem   run-cmake -G "Visual Studio 10 Win64" .
-
-for /F "delims=" %%i IN ('cmake "-DPRINT_PATH=1" -P %~dp0/FindSetEnv.cmake') DO set setenv=%%i
-if NOT "%setenv%" == "" call "%setenv%"
-cmake %*

support/fmt.pro

@@ -1,27 +0,0 @@
-# Staticlib configuration for qmake builds
-# For some reason qmake 3.1 fails to identify source dependencies and excludes format.cc and printf.cc
-# from compilation so it _MUST_ be called as qmake -nodepend
-# A workaround is implemented below: a custom compiler is defined which does not track dependencies
-
-TEMPLATE = lib
-
-TARGET = fmt
-
-QMAKE_EXT_CPP = .cc
-
-CONFIG = staticlib warn_on c++11
-
-FMT_SOURCES = \
-    ../src/format.cc \
-    ../src/posix.cc
-
-fmt.name = libfmt
-fmt.input = FMT_SOURCES
-fmt.output = ${QMAKE_FILE_BASE}$$QMAKE_EXT_OBJ
-fmt.clean = ${QMAKE_FILE_BASE}$$QMAKE_EXT_OBJ
-fmt.depends = ${QMAKE_FILE_IN}
-# QMAKE_RUN_CXX will not be expanded
-fmt.commands = $$QMAKE_CXX -c $$QMAKE_CXXFLAGS $$QMAKE_CXXFLAGS_WARN_ON $$QMAKE_CXXFLAGS_RELEASE_WITH_DEBUGINFO $$QMAKE_CXXFLAGS_CXX11 ${QMAKE_FILE_IN}
-fmt.variable_out = OBJECTS
-fmt.CONFIG = no_dependencies no_link
-QMAKE_EXTRA_COMPILERS += fmt

support/manage.py

@@ -5,6 +5,9 @@
 Usage:
   manage.py release [<branch>]
   manage.py site
+
+For the release command $FMT_TOKEN should contain a GitHub personal access token
+obtained from https://github.com/settings/tokens.
 """
 
 from __future__ import print_function
@@ -134,14 +137,40 @@ def update_site(env):
         if not os.path.exists(contents):
             os.rename(os.path.join(target_doc_dir, 'index.rst'), contents)
         # Fix issues in reference.rst/api.rst.
-        for filename in ['reference.rst', 'api.rst']:
+        for filename in ['reference.rst', 'api.rst', 'index.rst']:
             pattern = re.compile('doxygenfunction.. (bin|oct|hexu|hex)$', re.M)
             with rewrite(os.path.join(target_doc_dir, filename)) as b:
                 b.data = b.data.replace('std::ostream &', 'std::ostream&')
                 b.data = re.sub(pattern, r'doxygenfunction:: \1(int)', b.data)
                 b.data = b.data.replace('std::FILE*', 'std::FILE *')
                 b.data = b.data.replace('unsigned int', 'unsigned')
-                b.data = b.data.replace('operator""_', 'operator"" _')
+                #b.data = b.data.replace('operator""_', 'operator"" _')
+                b.data = b.data.replace(
+                    'format_to_n(OutputIt, size_t, string_view, Args&&',
+                    'format_to_n(OutputIt, size_t, const S&, const Args&')
+                b.data = b.data.replace(
+                    'format_to_n(OutputIt, std::size_t, string_view, Args&&',
+                    'format_to_n(OutputIt, std::size_t, const S&, const Args&')
+                if version == ('3.0.2'):
+                    b.data = b.data.replace(
+                        'fprintf(std::ostream&', 'fprintf(std::ostream &')
+                if version == ('5.3.0'):
+                    b.data = b.data.replace(
+                        'format_to(OutputIt, const S&, const Args&...)',
+                        'format_to(OutputIt, const S &, const Args &...)')
+                if version.startswith('5.') or version.startswith('6.'):
+                    b.data = b.data.replace(', size_t', ', std::size_t')
+                if version.startswith('7.'):
+                    b.data = b.data.replace(', std::size_t', ', size_t')
+                    b.data = b.data.replace('join(It, It', 'join(It, Sentinel')
+                b.data = b.data.replace('aa long', 'a long')
+                b.data = b.data.replace('serveral', 'several')
+                if version.startswith('6.2.'):
+                    b.data = b.data.replace(
+                        'vformat(const S&, basic_format_args<' +
+                        'buffer_context<Char>>)',
+                        'vformat(const S&, basic_format_args<' +
+                        'buffer_context<type_identity_t<Char>>>)')
         # Fix a broken link in index.rst.
         index = os.path.join(target_doc_dir, 'index.rst')
         with rewrite(index) as b:

support/rtd/index.rst

@@ -1,2 +1,2 @@
 If you are not redirected automatically, follow the
-`link to the fmt documentation <http://fmtlib.net/latest/>`_.
+`link to the fmt documentation <https://fmt.dev/latest/>`_.

support/rtd/theme/layout.html

@@ -2,15 +2,15 @@
 
 {% block extrahead %}
 <meta charset="UTF-8">
-<meta http-equiv="refresh" content="1;url=http://fmtlib.net/latest/">
+<meta http-equiv="refresh" content="1;url=https://fmt.dev/latest/">
 <script type="text/javascript">
-    window.location.href = "http://fmtlib.net/latest/"
+    window.location.href = "https://fmt.dev/latest/"
 </script>
 <title>Page Redirection</title>
 {% endblock %}
 
 {% block document %}
-If you are not redirected automatically, follow the <a href='http://fmtlib.net/latest/'>link to the fmt documentation</a>.
+If you are not redirected automatically, follow the <a href='https://fmt.dev/latest/'>link to the fmt documentation</a>.
 {% endblock %}
 
 {% block footer %}

support/travis-build.py

@@ -83,19 +83,25 @@ install_dir    = os.path.join(fmt_dir, "_install")
 build_dir      = os.path.join(fmt_dir, "_build")
 test_build_dir = os.path.join(fmt_dir, "_build_test")
 
-# Configure library.
+# Configure the library.
 makedirs_if_not_exist(build_dir)
 cmake_flags = [
     '-DCMAKE_INSTALL_PREFIX=' + install_dir, '-DCMAKE_BUILD_TYPE=' + build,
     '-DCMAKE_CXX_STANDARD=' + standard
 ]
+
+# Make sure the fuzzers still compile.
+main_cmake_flags = list(cmake_flags)
+if 'ENABLE_FUZZING' in os.environ:
+    main_cmake_flags += ['-DFMT_FUZZ=ON', '-DFMT_FUZZ_LINKMAIN=On']
+
 check_call(['cmake', '-DFMT_DOC=OFF', '-DFMT_PEDANTIC=ON', '-DFMT_WERROR=ON', fmt_dir] +
-           cmake_flags, cwd=build_dir)
+           main_cmake_flags, cwd=build_dir)
 
-# Build library.
-check_call(['make', '-j4'], cwd=build_dir)
+# Build the library.
+check_call(['cmake', '--build','.'], cwd=build_dir)
 
-# Test library.
+# Test the library.
 env = os.environ.copy()
 env['CTEST_OUTPUT_ON_FAILURE'] = '1'
 if call(['make', 'test'], env=env, cwd=build_dir):
@@ -103,7 +109,7 @@ if call(['make', 'test'], env=env, cwd=build_dir):
         print(f.read())
     sys.exit(-1)
 
-# Install library.
+# Install the library.
 check_call(['make', 'install'], cwd=build_dir)
 
 # Test installation.

support/update-coverity-branch.py

@@ -1,30 +0,0 @@
-#!/usr/bin/env python
-# Update the coverity branch from the master branch.
-# It is not done automatically because Coverity Scan limits
-# the number of submissions per day.
-
-from __future__ import print_function
-import shutil, tempfile
-from subprocess import check_output, STDOUT
-
-class Git:
-    def __init__(self, dir):
-        self.dir = dir
-
-    def __call__(self, *args):
-        output = check_output(['git'] + list(args), cwd=self.dir, stderr=STDOUT)
-        print(output)
-        return output
-
-dir = tempfile.mkdtemp()
-try:
-    git = Git(dir)
-    git('clone', '-b', 'coverity', 'git@github.com:fmtlib/fmt.git', dir)
-    output = git('merge', '-X', 'theirs', '--no-commit', 'origin/master')
-    if 'Fast-forward' not in output:
-        git('reset', 'HEAD', '.travis.yml')
-        git('checkout', '--', '.travis.yml')
-        git('commit', '-m', 'Update coverity branch')
-    git('push')
-finally:
-    shutil.rmtree(dir)

test/CMakeLists.txt

@@ -17,13 +17,18 @@ else ()
   target_compile_definitions(gmock PUBLIC GTEST_HAS_PTHREAD=0)
 endif ()
 
-if (NOT SUPPORTS_VARIADIC_TEMPLATES OR NOT SUPPORTS_INITIALIZER_LIST)
-  target_compile_definitions(gmock PUBLIC GTEST_LANG_CXX11=0)
-endif ()
+target_compile_definitions(gmock PUBLIC GTEST_LANG_CXX11=0)
 
-# Workaround a bug in implementation of variadic templates in MSVC11.
 if (MSVC)
+  # Workaround a bug in implementation of variadic templates in MSVC11.
   target_compile_definitions(gmock PUBLIC _VARIADIC_MAX=10)
+  
+  # Disable MSVC warnings of _CRT_INSECURE_DEPRECATE functions.
+  target_compile_definitions(gmock PRIVATE _CRT_SECURE_NO_WARNINGS)
+  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+    # Disable MSVC warnings of POSIX functions.
+    target_compile_options(gmock PUBLIC -Wno-deprecated-declarations)
+  endif ()
 endif ()
 
 # GTest doesn't detect <tuple> with clang.
@@ -33,15 +38,13 @@ endif ()
 
 # Silence MSVC tr1 deprecation warning in gmock.
 target_compile_definitions(gmock
-  PUBLIC _SILENCE_TR1_NAMESPACE_DEPRECATION_WARNING=0)
+  PUBLIC _SILENCE_TR1_NAMESPACE_DEPRECATION_WARNING=1)
 
 #------------------------------------------------------------------------------
 # Build the actual library tests
 
 set(TEST_MAIN_SRC test-main.cc gtest-extra.cc gtest-extra.h util.cc)
 add_library(test-main STATIC ${TEST_MAIN_SRC})
-target_compile_definitions(test-main PUBLIC
-  FMT_USE_FILE_DESCRIPTORS=$<BOOL:${HAVE_OPEN}>)
 target_include_directories(test-main SYSTEM PUBLIC gtest gmock)
 target_link_libraries(test-main gmock fmt)
 
@@ -74,44 +77,61 @@ function(add_fmt_test name)
   target_link_libraries(${name} test-main)
 
   # Define if certain C++ features can be used.
-  target_compile_definitions(${name} PRIVATE
-    FMT_USE_TYPE_TRAITS=$<BOOL:${SUPPORTS_TYPE_TRAITS}>
-    FMT_USE_ENUM_BASE=$<BOOL:${SUPPORTS_ENUM_BASE}>)
   if (FMT_PEDANTIC)
     target_compile_options(${name} PRIVATE ${PEDANTIC_COMPILE_FLAGS})
   endif ()
+  if (FMT_WERROR)
+    target_compile_options(${name} PRIVATE ${WERROR_FLAG})
+  endif ()
   target_include_directories(${name} SYSTEM PUBLIC gtest gmock)
   add_test(NAME ${name} COMMAND ${name})
 endfunction()
 
 add_fmt_test(assert-test)
 add_fmt_test(chrono-test)
+add_fmt_test(color-test)
 add_fmt_test(core-test)
 add_fmt_test(gtest-extra-test)
 add_fmt_test(format-test mock-allocator.h)
+if (MSVC)
+  target_compile_options(format-test PRIVATE /bigobj)
+endif ()
 if (NOT (MSVC AND BUILD_SHARED_LIBS))
   add_fmt_test(format-impl-test)
 endif ()
 add_fmt_test(locale-test)
 add_fmt_test(ostream-test)
+add_fmt_test(compile-test)
 add_fmt_test(printf-test)
-add_fmt_test(time-test)
-add_fmt_test(custom-formatter-test)
 add_fmt_test(ranges-test)
+add_fmt_test(scan-test)
 
-if (HAVE_OPEN)
+if (NOT DEFINED MSVC_STATIC_RUNTIME AND MSVC)
+  foreach (flag_var
+			 CMAKE_CXX_FLAGS CMAKE_CXX_FLAGS_DEBUG CMAKE_CXX_FLAGS_RELEASE
+			 CMAKE_CXX_FLAGS_MINSIZEREL CMAKE_CXX_FLAGS_RELWITHDEBINFO)
+	if (${flag_var} MATCHES "^(/|-)(MT|MTd)")
+	  set(MSVC_STATIC_RUNTIME ON)
+	  break()
+	endif()
+  endforeach()
+endif()
+
+if (NOT MSVC_STATIC_RUNTIME)
   add_fmt_executable(posix-mock-test
     posix-mock-test.cc ../src/format.cc ${TEST_MAIN_SRC})
   target_include_directories(
     posix-mock-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
-  target_compile_definitions(posix-mock-test PRIVATE FMT_USE_FILE_DESCRIPTORS=1)
   target_link_libraries(posix-mock-test gmock)
   target_include_directories(posix-mock-test SYSTEM PUBLIC gtest gmock)
   if (FMT_PEDANTIC)
     target_compile_options(posix-mock-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
   endif ()
+  if (HAVE_STRTOD_L)
+    target_compile_definitions(posix-mock-test PRIVATE FMT_LOCALE)
+  endif ()
   add_test(NAME posix-mock-test COMMAND posix-mock-test)
-  add_fmt_test(posix-test)
+  add_fmt_test(os-test)
 endif ()
 
 add_fmt_executable(header-only-test
@@ -126,41 +146,41 @@ else ()
   target_compile_definitions(header-only-test PRIVATE FMT_HEADER_ONLY=1)
 endif ()
 
-# Test that the library can be compiled with exceptions disabled.
-# -fno-exception is broken in icc: https://github.com/fmtlib/fmt/issues/822.
-if (NOT CMAKE_CXX_COMPILER_ID STREQUAL "Intel")
-  check_cxx_compiler_flag(-fno-exceptions HAVE_FNO_EXCEPTIONS_FLAG)
-endif ()
-if (HAVE_FNO_EXCEPTIONS_FLAG)
-  add_library(noexception-test ../src/format.cc)
-  target_include_directories(
-    noexception-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
-  target_compile_options(noexception-test PRIVATE -fno-exceptions)
-  if (FMT_PEDANTIC)
-    target_compile_options(noexception-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
-  endif ()
-  target_include_directories(noexception-test SYSTEM PUBLIC gtest gmock)
-endif ()
-
 message(STATUS "FMT_PEDANTIC: ${FMT_PEDANTIC}")
 
 if (FMT_PEDANTIC)
-  # Test that the library compiles without windows.h.
-  if (CMAKE_SYSTEM_NAME STREQUAL "Windows")
-    add_library(no-windows-h-test ../src/format.cc)
-    target_include_directories(
-      no-windows-h-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
-    target_compile_definitions(no-windows-h-test PRIVATE FMT_USE_WINDOWS_H=0)
-    if (FMT_PEDANTIC)
-      target_compile_options(no-windows-h-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
-    endif ()
-    target_include_directories(no-windows-h-test SYSTEM PUBLIC gtest gmock)
+  # MSVC fails to compile GMock when C++17 is enabled.
+  if (FMT_HAS_VARIANT AND NOT MSVC)
+    add_fmt_test(std-format-test)
+    set_property(TARGET std-format-test PROPERTY CXX_STANDARD 17)
   endif ()
 
-  add_test(compile-test ${CMAKE_CTEST_COMMAND}
+  # Test that the library can be compiled with exceptions disabled.
+  # -fno-exception is broken in icc: https://github.com/fmtlib/fmt/issues/822.
+  if (NOT CMAKE_CXX_COMPILER_ID STREQUAL "Intel")
+    check_cxx_compiler_flag(-fno-exceptions HAVE_FNO_EXCEPTIONS_FLAG)
+  endif ()
+  if (HAVE_FNO_EXCEPTIONS_FLAG)
+    add_library(noexception-test ../src/format.cc)
+    target_include_directories(
+      noexception-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
+    target_compile_options(noexception-test PRIVATE -fno-exceptions)
+    if (FMT_PEDANTIC)
+      target_compile_options(noexception-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
+    endif ()
+  endif ()
+
+  # Test that the library compiles without locale.
+  add_library(nolocale-test ../src/format.cc)
+  target_include_directories(
+    nolocale-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
+  target_compile_definitions(
+    nolocale-test PRIVATE FMT_STATIC_THOUSANDS_SEPARATOR=1)
+
+  add_test(compile-error-test ${CMAKE_CTEST_COMMAND}
     --build-and-test
-    "${CMAKE_CURRENT_SOURCE_DIR}/compile-test"
-    "${CMAKE_CURRENT_BINARY_DIR}/compile-test"
+    "${CMAKE_CURRENT_SOURCE_DIR}/compile-error-test"
+    "${CMAKE_CURRENT_BINARY_DIR}/compile-error-test"
     --build-generator ${CMAKE_GENERATOR}
     --build-makeprogram ${CMAKE_MAKE_PROGRAM}
     --build-options
@@ -202,3 +222,23 @@ if (FMT_PEDANTIC AND NOT WIN32)
     "-DPEDANTIC_COMPILE_FLAGS=${PEDANTIC_COMPILE_FLAGS}"
     "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}")
 endif ()
+
+# Activate optional CUDA tests if CUDA is found. For version selection see
+# https://docs.nvidia.com/cuda/cuda-c-programming-guide/index.html#cpp14-language-features
+if (FMT_CUDA_TEST)
+  if (${CMAKE_VERSION} VERSION_LESS 3.15)
+    find_package(CUDA 9.0)
+  else ()
+    include(CheckLanguage)
+    check_language(CUDA)
+    if (CMAKE_CUDA_COMPILER)
+      enable_language(CUDA OPTIONAL)
+      set(CUDA_FOUND TRUE)
+    endif ()
+  endif ()
+
+  if (CUDA_FOUND)
+    add_subdirectory(cuda-test)
+    add_test(NAME cuda-test COMMAND fmt-in-cuda-test)
+  endif ()
+endif ()

test/add-subdirectory-test/CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.1.0)
+cmake_minimum_required(VERSION 3.1...3.18)
 
 project(fmt-test)
 

test/assert-test.cc

@@ -1,4 +1,8 @@
-// Formatting library for C++ - assertion tests
+// Formatting library for C++ - FMT_ASSERT test
+//
+// It is a separate test to minimize the number of EXPECT_DEBUG_DEATH checks
+// which are slow on some platforms. In other tests FMT_ASSERT is made to throw
+// an exception which is much faster and easier to check.
 //
 // Copyright (c) 2012 - present, Victor Zverovich
 // All rights reserved.
@@ -8,15 +12,21 @@
 #include "fmt/core.h"
 #include "gtest.h"
 
-#if GTEST_HAS_DEATH_TEST
-# define EXPECT_DEBUG_DEATH_IF_SUPPORTED(statement, regex) \
-    EXPECT_DEBUG_DEATH(statement, regex)
-#else
-# define EXPECT_DEBUG_DEATH_IF_SUPPORTED(statement, regex) \
-    GTEST_UNSUPPORTED_DEATH_TEST_(statement, regex, )
-#endif
-
 TEST(AssertTest, Fail) {
-  EXPECT_DEBUG_DEATH_IF_SUPPORTED(
-      FMT_ASSERT(false, "don't panic!"), "don't panic!");
+#if GTEST_HAS_DEATH_TEST
+  EXPECT_DEBUG_DEATH(FMT_ASSERT(false, "don't panic!"), "don't panic!");
+#else
+  fmt::print("warning: death tests are not supported\n");
+#endif
+}
+
+bool test_condition = false;
+
+TEST(AssertTest, DanglingElse) {
+  bool executed_else = false;
+  if (test_condition)
+    FMT_ASSERT(true, "");
+  else
+    executed_else = true;
+  EXPECT_TRUE(executed_else);
 }

test/chrono-test.cc

@@ -5,11 +5,16 @@
 //
 // For the license information refer to format.h.
 
+#ifdef WIN32
+#  define _CRT_SECURE_NO_WARNINGS
+#endif
+
 #include "fmt/chrono.h"
-#include "gtest-extra.h"
 
 #include <iomanip>
 
+#include "gtest-extra.h"
+
 std::tm make_tm() {
   auto time = std::tm();
   time.tm_mday = 1;
@@ -34,21 +39,82 @@ std::tm make_second(int s) {
   return time;
 }
 
-std::string format_tm(const std::tm &time, const char *spec,
-                      const std::locale &loc) {
-  auto &facet = std::use_facet<std::time_put<char>>(loc);
+std::string format_tm(const std::tm& time, const char* spec,
+                      const std::locale& loc) {
+  auto& facet = std::use_facet<std::time_put<char>>(loc);
   std::ostringstream os;
   os.imbue(loc);
   facet.put(os, os, ' ', &time, spec, spec + std::strlen(spec));
   return os.str();
 }
 
-#define EXPECT_TIME(spec, time, duration) { \
-    std::locale loc("ja_JP.utf8"); \
-    EXPECT_EQ(format_tm(time, spec, loc), \
+TEST(TimeTest, Format) {
+  std::tm tm = std::tm();
+  tm.tm_year = 116;
+  tm.tm_mon = 3;
+  tm.tm_mday = 25;
+  EXPECT_EQ("The date is 2016-04-25.",
+            fmt::format("The date is {:%Y-%m-%d}.", tm));
+}
+
+TEST(TimeTest, GrowBuffer) {
+  std::string s = "{:";
+  for (int i = 0; i < 30; ++i) s += "%c";
+  s += "}\n";
+  std::time_t t = std::time(nullptr);
+  fmt::format(s, *std::localtime(&t));
+}
+
+TEST(TimeTest, FormatToEmptyContainer) {
+  std::string s;
+  auto time = std::tm();
+  time.tm_sec = 42;
+  fmt::format_to(std::back_inserter(s), "{:%S}", time);
+  EXPECT_EQ(s, "42");
+}
+
+TEST(TimeTest, EmptyResult) { EXPECT_EQ("", fmt::format("{}", std::tm())); }
+
+static bool EqualTime(const std::tm& lhs, const std::tm& rhs) {
+  return lhs.tm_sec == rhs.tm_sec && lhs.tm_min == rhs.tm_min &&
+         lhs.tm_hour == rhs.tm_hour && lhs.tm_mday == rhs.tm_mday &&
+         lhs.tm_mon == rhs.tm_mon && lhs.tm_year == rhs.tm_year &&
+         lhs.tm_wday == rhs.tm_wday && lhs.tm_yday == rhs.tm_yday &&
+         lhs.tm_isdst == rhs.tm_isdst;
+}
+
+TEST(TimeTest, LocalTime) {
+  std::time_t t = std::time(nullptr);
+  std::tm tm = *std::localtime(&t);
+  EXPECT_TRUE(EqualTime(tm, fmt::localtime(t)));
+}
+
+TEST(TimeTest, GMTime) {
+  std::time_t t = std::time(nullptr);
+  std::tm tm = *std::gmtime(&t);
+  EXPECT_TRUE(EqualTime(tm, fmt::gmtime(t)));
+}
+
+TEST(TimeTest, TimePoint) {
+  std::chrono::system_clock::time_point point = std::chrono::system_clock::now();
+
+  std::time_t t = std::chrono::system_clock::to_time_t(point);
+  std::tm tm = *std::localtime(&t);
+  char strftime_output[256];
+  std::strftime(strftime_output, sizeof(strftime_output), "It is %Y-%m-%d %H:%M:%S", &tm);
+
+  EXPECT_EQ(strftime_output, fmt::format("It is {:%Y-%m-%d %H:%M:%S}", point));
+}
+
+#define EXPECT_TIME(spec, time, duration)                 \
+  {                                                       \
+    std::locale loc("ja_JP.utf8");                        \
+    EXPECT_EQ(format_tm(time, spec, loc),                 \
               fmt::format(loc, "{:" spec "}", duration)); \
   }
 
+#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
+
 TEST(ChronoTest, FormatDefault) {
   EXPECT_EQ("42s", fmt::format("{}", std::chrono::seconds(42)));
   EXPECT_EQ("42as",
@@ -83,12 +149,54 @@ TEST(ChronoTest, FormatDefault) {
             fmt::format("{}", std::chrono::duration<int, std::exa>(42)));
   EXPECT_EQ("42m", fmt::format("{}", std::chrono::minutes(42)));
   EXPECT_EQ("42h", fmt::format("{}", std::chrono::hours(42)));
-  EXPECT_EQ("42[15]s",
-            fmt::format("{}",
-                        std::chrono::duration<int, std::ratio<15, 1>>(42)));
-  EXPECT_EQ("42[15/4]s",
-            fmt::format("{}",
-                        std::chrono::duration<int, std::ratio<15, 4>>(42)));
+  EXPECT_EQ(
+      "42[15]s",
+      fmt::format("{}", std::chrono::duration<int, std::ratio<15, 1>>(42)));
+  EXPECT_EQ(
+      "42[15/4]s",
+      fmt::format("{}", std::chrono::duration<int, std::ratio<15, 4>>(42)));
+}
+
+TEST(ChronoTest, FormatWide) {
+  EXPECT_EQ(L"42s", fmt::format(L"{}", std::chrono::seconds(42)));
+  EXPECT_EQ(L"42as",
+            fmt::format(L"{}", std::chrono::duration<int, std::atto>(42)));
+  EXPECT_EQ(L"42fs",
+            fmt::format(L"{}", std::chrono::duration<int, std::femto>(42)));
+  EXPECT_EQ(L"42ps",
+            fmt::format(L"{}", std::chrono::duration<int, std::pico>(42)));
+  EXPECT_EQ(L"42ns", fmt::format(L"{}", std::chrono::nanoseconds(42)));
+  EXPECT_EQ(L"42\u00B5s", fmt::format(L"{}", std::chrono::microseconds(42)));
+  EXPECT_EQ(L"42ms", fmt::format(L"{}", std::chrono::milliseconds(42)));
+  EXPECT_EQ(L"42cs",
+            fmt::format(L"{}", std::chrono::duration<int, std::centi>(42)));
+  EXPECT_EQ(L"42ds",
+            fmt::format(L"{}", std::chrono::duration<int, std::deci>(42)));
+  EXPECT_EQ(L"42s", fmt::format(L"{}", std::chrono::seconds(42)));
+  EXPECT_EQ(L"42das",
+            fmt::format(L"{}", std::chrono::duration<int, std::deca>(42)));
+  EXPECT_EQ(L"42hs",
+            fmt::format(L"{}", std::chrono::duration<int, std::hecto>(42)));
+  EXPECT_EQ(L"42ks",
+            fmt::format(L"{}", std::chrono::duration<int, std::kilo>(42)));
+  EXPECT_EQ(L"42Ms",
+            fmt::format(L"{}", std::chrono::duration<int, std::mega>(42)));
+  EXPECT_EQ(L"42Gs",
+            fmt::format(L"{}", std::chrono::duration<int, std::giga>(42)));
+  EXPECT_EQ(L"42Ts",
+            fmt::format(L"{}", std::chrono::duration<int, std::tera>(42)));
+  EXPECT_EQ(L"42Ps",
+            fmt::format(L"{}", std::chrono::duration<int, std::peta>(42)));
+  EXPECT_EQ(L"42Es",
+            fmt::format(L"{}", std::chrono::duration<int, std::exa>(42)));
+  EXPECT_EQ(L"42m", fmt::format(L"{}", std::chrono::minutes(42)));
+  EXPECT_EQ(L"42h", fmt::format(L"{}", std::chrono::hours(42)));
+  EXPECT_EQ(
+      L"42[15]s",
+      fmt::format(L"{}", std::chrono::duration<int, std::ratio<15, 1>>(42)));
+  EXPECT_EQ(
+      L"42[15/4]s",
+      fmt::format(L"{}", std::chrono::duration<int, std::ratio<15, 4>>(42)));
 }
 
 TEST(ChronoTest, Align) {
@@ -103,7 +211,8 @@ TEST(ChronoTest, Align) {
             fmt::format("{:>12%H:%M:%S}", std::chrono::seconds(12345)));
   EXPECT_EQ("~~03:25:45~~",
             fmt::format("{:~^12%H:%M:%S}", std::chrono::seconds(12345)));
-
+  EXPECT_EQ("03:25:45    ",
+            fmt::format("{:{}%H:%M:%S}", std::chrono::seconds(12345), 12));
 }
 
 TEST(ChronoTest, FormatSpecs) {
@@ -131,6 +240,8 @@ TEST(ChronoTest, FormatSpecs) {
             fmt::format("{:%H:%M:%S}", std::chrono::seconds(12345)));
   EXPECT_EQ("03:25", fmt::format("{:%R}", std::chrono::seconds(12345)));
   EXPECT_EQ("03:25:45", fmt::format("{:%T}", std::chrono::seconds(12345)));
+  EXPECT_EQ("12345", fmt::format("{:%Q}", std::chrono::seconds(12345)));
+  EXPECT_EQ("s", fmt::format("{:%q}", std::chrono::seconds(12345)));
 }
 
 TEST(ChronoTest, InvalidSpecs) {
@@ -151,8 +262,6 @@ TEST(ChronoTest, InvalidSpecs) {
   EXPECT_THROW_MSG(fmt::format("{:%B}", sec), fmt::format_error, "no date");
   EXPECT_THROW_MSG(fmt::format("{:%z}", sec), fmt::format_error, "no date");
   EXPECT_THROW_MSG(fmt::format("{:%Z}", sec), fmt::format_error, "no date");
-  EXPECT_THROW_MSG(fmt::format("{:%q}", sec), fmt::format_error,
-                   "invalid format");
   EXPECT_THROW_MSG(fmt::format("{:%Eq}", sec), fmt::format_error,
                    "invalid format");
   EXPECT_THROW_MSG(fmt::format("{:%Oq}", sec), fmt::format_error,
@@ -160,13 +269,14 @@ TEST(ChronoTest, InvalidSpecs) {
 }
 
 TEST(ChronoTest, Locale) {
-  const char *loc_name = "ja_JP.utf8";
+  const char* loc_name = "ja_JP.utf8";
   bool has_locale = false;
   std::locale loc;
   try {
     loc = std::locale(loc_name);
     has_locale = true;
-  } catch (const std::runtime_error &) {}
+  } catch (const std::runtime_error&) {
+  }
   if (!has_locale) {
     fmt::print("{} locale is missing.\n", loc_name);
     return;
@@ -183,3 +293,106 @@ TEST(ChronoTest, Locale) {
   EXPECT_TIME("%r", time, sec);
   EXPECT_TIME("%p", time, sec);
 }
+
+typedef std::chrono::duration<double, std::milli> dms;
+
+TEST(ChronoTest, FormatDefaultFP) {
+  typedef std::chrono::duration<float> fs;
+  EXPECT_EQ("1.234s", fmt::format("{}", fs(1.234)));
+  typedef std::chrono::duration<float, std::milli> fms;
+  EXPECT_EQ("1.234ms", fmt::format("{}", fms(1.234)));
+  typedef std::chrono::duration<double> ds;
+  EXPECT_EQ("1.234s", fmt::format("{}", ds(1.234)));
+  EXPECT_EQ("1.234ms", fmt::format("{}", dms(1.234)));
+}
+
+TEST(ChronoTest, FormatPrecision) {
+  EXPECT_THROW_MSG(fmt::format("{:.2}", std::chrono::seconds(42)),
+                   fmt::format_error,
+                   "precision not allowed for this argument type");
+  EXPECT_EQ("1.2ms", fmt::format("{:.1}", dms(1.234)));
+  EXPECT_EQ("1.23ms", fmt::format("{:.{}}", dms(1.234), 2));
+}
+
+TEST(ChronoTest, FormatFullSpecs) {
+  EXPECT_EQ("1.2ms ", fmt::format("{:6.1}", dms(1.234)));
+  EXPECT_EQ("  1.23ms", fmt::format("{:>8.{}}", dms(1.234), 2));
+  EXPECT_EQ(" 1.2ms ", fmt::format("{:^{}.{}}", dms(1.234), 7, 1));
+  EXPECT_EQ(" 1.23ms ", fmt::format("{0:^{2}.{1}}", dms(1.234), 2, 8));
+  EXPECT_EQ("=1.234ms=", fmt::format("{:=^{}.{}}", dms(1.234), 9, 3));
+  EXPECT_EQ("*1.2340ms*", fmt::format("{:*^10.4}", dms(1.234)));
+}
+
+TEST(ChronoTest, FormatSimpleQq) {
+  typedef std::chrono::duration<float> fs;
+  EXPECT_EQ("1.234 s", fmt::format("{:%Q %q}", fs(1.234)));
+  typedef std::chrono::duration<float, std::milli> fms;
+  EXPECT_EQ("1.234 ms", fmt::format("{:%Q %q}", fms(1.234)));
+  typedef std::chrono::duration<double> ds;
+  EXPECT_EQ("1.234 s", fmt::format("{:%Q %q}", ds(1.234)));
+  EXPECT_EQ("1.234 ms", fmt::format("{:%Q %q}", dms(1.234)));
+}
+
+TEST(ChronoTest, FormatPrecisionQq) {
+  EXPECT_THROW_MSG(fmt::format("{:.2%Q %q}", std::chrono::seconds(42)),
+                   fmt::format_error,
+                   "precision not allowed for this argument type");
+  EXPECT_EQ("1.2 ms", fmt::format("{:.1%Q %q}", dms(1.234)));
+  EXPECT_EQ("1.23 ms", fmt::format("{:.{}%Q %q}", dms(1.234), 2));
+}
+
+TEST(ChronoTest, FormatFullSpecsQq) {
+  EXPECT_EQ("1.2 ms ", fmt::format("{:7.1%Q %q}", dms(1.234)));
+  EXPECT_EQ(" 1.23 ms", fmt::format("{:>8.{}%Q %q}", dms(1.234), 2));
+  EXPECT_EQ(" 1.2 ms ", fmt::format("{:^{}.{}%Q %q}", dms(1.234), 8, 1));
+  EXPECT_EQ(" 1.23 ms ", fmt::format("{0:^{2}.{1}%Q %q}", dms(1.234), 2, 9));
+  EXPECT_EQ("=1.234 ms=", fmt::format("{:=^{}.{}%Q %q}", dms(1.234), 10, 3));
+  EXPECT_EQ("*1.2340 ms*", fmt::format("{:*^11.4%Q %q}", dms(1.234)));
+}
+
+TEST(ChronoTest, InvalidWidthId) {
+  EXPECT_THROW(fmt::format("{:{o}", std::chrono::seconds(0)),
+               fmt::format_error);
+}
+
+TEST(ChronoTest, InvalidColons) {
+  EXPECT_THROW(fmt::format("{0}=:{0::", std::chrono::seconds(0)),
+               fmt::format_error);
+}
+
+TEST(ChronoTest, NegativeDurations) {
+  EXPECT_EQ("-12345", fmt::format("{:%Q}", std::chrono::seconds(-12345)));
+  EXPECT_EQ("-03:25:45",
+            fmt::format("{:%H:%M:%S}", std::chrono::seconds(-12345)));
+  EXPECT_EQ("-00:01",
+            fmt::format("{:%M:%S}", std::chrono::duration<double>(-1)));
+  EXPECT_EQ("s", fmt::format("{:%q}", std::chrono::seconds(-12345)));
+  EXPECT_EQ("-00.127",
+            fmt::format("{:%S}",
+                        std::chrono::duration<signed char, std::milli>{-127}));
+  auto min = std::numeric_limits<int>::min();
+  EXPECT_EQ(fmt::format("{}", min),
+            fmt::format("{:%Q}", std::chrono::duration<int>(min)));
+}
+
+TEST(ChronoTest, SpecialDurations) {
+  EXPECT_EQ(
+      "40.",
+      fmt::format("{:%S}", std::chrono::duration<double>(1e20)).substr(0, 3));
+  auto nan = std::numeric_limits<double>::quiet_NaN();
+  EXPECT_EQ(
+      "nan nan nan nan nan:nan nan",
+      fmt::format("{:%I %H %M %S %R %r}", std::chrono::duration<double>(nan)));
+  fmt::format("{:%S}",
+              std::chrono::duration<float, std::atto>(1.79400457e+31f));
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<float, std::exa>(1)),
+            "1Es");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<float, std::atto>(1)),
+            "1as");
+  EXPECT_EQ(fmt::format("{:%R}", std::chrono::duration<char, std::mega>{2}),
+            "03:33");
+  EXPECT_EQ(fmt::format("{:%T}", std::chrono::duration<char, std::mega>{2}),
+            "03:33:20");
+}
+
+#endif  // FMT_STATIC_THOUSANDS_SEPARATOR

test/color-test.cc

@@ -0,0 +1,99 @@
+// Formatting library for C++ - color tests
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include "fmt/color.h"
+
+#include <iterator>
+#include <string>
+#include <utility>
+
+#include "gtest-extra.h"
+
+TEST(ColorsTest, ColorsPrint) {
+  EXPECT_WRITE(stdout, fmt::print(fg(fmt::rgb(255, 20, 30)), "rgb(255,20,30)"),
+               "\x1b[38;2;255;020;030mrgb(255,20,30)\x1b[0m");
+  EXPECT_WRITE(stdout, fmt::print(fg(fmt::color::blue), "blue"),
+               "\x1b[38;2;000;000;255mblue\x1b[0m");
+  EXPECT_WRITE(
+      stdout,
+      fmt::print(fg(fmt::color::blue) | bg(fmt::color::red), "two color"),
+      "\x1b[38;2;000;000;255m\x1b[48;2;255;000;000mtwo color\x1b[0m");
+  EXPECT_WRITE(stdout, fmt::print(fmt::emphasis::bold, "bold"),
+               "\x1b[1mbold\x1b[0m");
+  EXPECT_WRITE(stdout, fmt::print(fmt::emphasis::italic, "italic"),
+               "\x1b[3mitalic\x1b[0m");
+  EXPECT_WRITE(stdout, fmt::print(fmt::emphasis::underline, "underline"),
+               "\x1b[4munderline\x1b[0m");
+  EXPECT_WRITE(stdout,
+               fmt::print(fmt::emphasis::strikethrough, "strikethrough"),
+               "\x1b[9mstrikethrough\x1b[0m");
+  EXPECT_WRITE(
+      stdout,
+      fmt::print(fg(fmt::color::blue) | fmt::emphasis::bold, "blue/bold"),
+      "\x1b[1m\x1b[38;2;000;000;255mblue/bold\x1b[0m");
+  EXPECT_WRITE(stderr, fmt::print(stderr, fmt::emphasis::bold, "bold error"),
+               "\x1b[1mbold error\x1b[0m");
+  EXPECT_WRITE(stderr, fmt::print(stderr, fg(fmt::color::blue), "blue log"),
+               "\x1b[38;2;000;000;255mblue log\x1b[0m");
+  EXPECT_WRITE(stdout, fmt::print(fmt::text_style(), "hi"), "hi");
+  EXPECT_WRITE(stdout, fmt::print(fg(fmt::terminal_color::red), "tred"),
+               "\x1b[31mtred\x1b[0m");
+  EXPECT_WRITE(stdout, fmt::print(bg(fmt::terminal_color::cyan), "tcyan"),
+               "\x1b[46mtcyan\x1b[0m");
+  EXPECT_WRITE(stdout,
+               fmt::print(fg(fmt::terminal_color::bright_green), "tbgreen"),
+               "\x1b[92mtbgreen\x1b[0m");
+  EXPECT_WRITE(stdout,
+               fmt::print(bg(fmt::terminal_color::bright_magenta), "tbmagenta"),
+               "\x1b[105mtbmagenta\x1b[0m");
+}
+
+TEST(ColorsTest, Format) {
+  EXPECT_EQ(fmt::format(fg(fmt::rgb(255, 20, 30)), "rgb(255,20,30)"),
+            "\x1b[38;2;255;020;030mrgb(255,20,30)\x1b[0m");
+  EXPECT_EQ(fmt::format(fg(fmt::rgb(255, 20, 30)), L"rgb(255,20,30) wide"),
+            L"\x1b[38;2;255;020;030mrgb(255,20,30) wide\x1b[0m");
+  EXPECT_EQ(fmt::format(fg(fmt::color::blue), "blue"),
+            "\x1b[38;2;000;000;255mblue\x1b[0m");
+  EXPECT_EQ(
+      fmt::format(fg(fmt::color::blue) | bg(fmt::color::red), "two color"),
+      "\x1b[38;2;000;000;255m\x1b[48;2;255;000;000mtwo color\x1b[0m");
+  EXPECT_EQ(fmt::format(fmt::emphasis::bold, "bold"), "\x1b[1mbold\x1b[0m");
+  EXPECT_EQ(fmt::format(fmt::emphasis::italic, "italic"),
+            "\x1b[3mitalic\x1b[0m");
+  EXPECT_EQ(fmt::format(fmt::emphasis::underline, "underline"),
+            "\x1b[4munderline\x1b[0m");
+  EXPECT_EQ(fmt::format(fmt::emphasis::strikethrough, "strikethrough"),
+            "\x1b[9mstrikethrough\x1b[0m");
+  EXPECT_EQ(
+      fmt::format(fg(fmt::color::blue) | fmt::emphasis::bold, "blue/bold"),
+      "\x1b[1m\x1b[38;2;000;000;255mblue/bold\x1b[0m");
+  EXPECT_EQ(fmt::format(fmt::emphasis::bold, "bold error"),
+            "\x1b[1mbold error\x1b[0m");
+  EXPECT_EQ(fmt::format(fg(fmt::color::blue), "blue log"),
+            "\x1b[38;2;000;000;255mblue log\x1b[0m");
+  EXPECT_EQ(fmt::format(fmt::text_style(), "hi"), "hi");
+  EXPECT_EQ(fmt::format(fg(fmt::terminal_color::red), "tred"),
+            "\x1b[31mtred\x1b[0m");
+  EXPECT_EQ(fmt::format(bg(fmt::terminal_color::cyan), "tcyan"),
+            "\x1b[46mtcyan\x1b[0m");
+  EXPECT_EQ(fmt::format(fg(fmt::terminal_color::bright_green), "tbgreen"),
+            "\x1b[92mtbgreen\x1b[0m");
+  EXPECT_EQ(fmt::format(bg(fmt::terminal_color::bright_magenta), "tbmagenta"),
+            "\x1b[105mtbmagenta\x1b[0m");
+  EXPECT_EQ(fmt::format(fg(fmt::terminal_color::red), "{}", "foo"),
+            "\x1b[31mfoo\x1b[0m");
+}
+
+TEST(ColorsTest, FormatToOutAcceptsTextStyle) {
+  fmt::text_style ts = fg(fmt::rgb(255, 20, 30));
+  std::string out;
+  fmt::format_to(std::back_inserter(out), ts, "rgb(255,20,30){}{}{}", 1, 2, 3);
+
+  EXPECT_EQ(fmt::to_string(out),
+            "\x1b[38;2;255;020;030mrgb(255,20,30)123\x1b[0m");
+}

test/compile-error-test/CMakeLists.txt

@@ -1,6 +1,6 @@
 # Test if compile errors are produced where necessary.
 
-cmake_minimum_required(VERSION 3.1.0)
+cmake_minimum_required(VERSION 3.1...3.18)
 
 include(CheckCXXSourceCompiles)
 include(CheckCXXCompilerFlag)

test/compile-test.cc

@@ -0,0 +1,173 @@
+// Formatting library for C++ - formatting library tests
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include <string>
+#include <type_traits>
+
+// Check that fmt/compile.h compiles with windows.h included before it.
+#ifdef _WIN32
+#  include <windows.h>
+#endif
+
+#include "fmt/compile.h"
+#include "gmock.h"
+#include "gtest-extra.h"
+#include "util.h"
+
+// compiletime_prepared_parts_type_provider is useful only with relaxed
+// constexpr.
+#if FMT_USE_CONSTEXPR
+template <unsigned EXPECTED_PARTS_COUNT, typename Format>
+void check_prepared_parts_type(Format format) {
+  typedef fmt::detail::compiled_format_base<decltype(format)> provider;
+  typedef fmt::detail::format_part<char>
+      expected_parts_type[EXPECTED_PARTS_COUNT];
+  static_assert(std::is_same<typename provider::parts_container,
+                             expected_parts_type>::value,
+                "CompileTimePreparedPartsTypeProvider test failed");
+}
+
+TEST(CompileTest, CompileTimePreparedPartsTypeProvider) {
+  check_prepared_parts_type<1u>(FMT_STRING("text"));
+  check_prepared_parts_type<1u>(FMT_STRING("{}"));
+  check_prepared_parts_type<2u>(FMT_STRING("text{}"));
+  check_prepared_parts_type<2u>(FMT_STRING("{}text"));
+  check_prepared_parts_type<3u>(FMT_STRING("text{}text"));
+  check_prepared_parts_type<3u>(FMT_STRING("{:{}.{}} {:{}}"));
+
+  check_prepared_parts_type<3u>(FMT_STRING("{{{}}}"));   // '{', 'argument', '}'
+  check_prepared_parts_type<2u>(FMT_STRING("text{{"));   // 'text', '{'
+  check_prepared_parts_type<3u>(FMT_STRING("text{{ "));  // 'text', '{', ' '
+  check_prepared_parts_type<2u>(FMT_STRING("}}text"));   // '}', text
+  check_prepared_parts_type<2u>(FMT_STRING("text}}text"));  // 'text}', 'text'
+  check_prepared_parts_type<4u>(
+      FMT_STRING("text{{}}text"));  // 'text', '{', '}', 'text'
+}
+#endif
+
+TEST(CompileTest, PassStringLiteralFormat) {
+  const auto prepared = fmt::detail::compile<int>("test {}");
+  EXPECT_EQ("test 42", fmt::format(prepared, 42));
+  const auto wprepared = fmt::detail::compile<int>(L"test {}");
+  EXPECT_EQ(L"test 42", fmt::format(wprepared, 42));
+}
+
+TEST(CompileTest, FormatToArrayOfChars) {
+  char buffer[32] = {0};
+  const auto prepared = fmt::detail::compile<int>("4{}");
+  fmt::format_to(fmt::detail::make_checked(buffer, 32), prepared, 2);
+  EXPECT_EQ(std::string("42"), buffer);
+  wchar_t wbuffer[32] = {0};
+  const auto wprepared = fmt::detail::compile<int>(L"4{}");
+  fmt::format_to(fmt::detail::make_checked(wbuffer, 32), wprepared, 2);
+  EXPECT_EQ(std::wstring(L"42"), wbuffer);
+}
+
+TEST(CompileTest, FormatToIterator) {
+  std::string s(2, ' ');
+  const auto prepared = fmt::detail::compile<int>("4{}");
+  fmt::format_to(s.begin(), prepared, 2);
+  EXPECT_EQ("42", s);
+  std::wstring ws(2, L' ');
+  const auto wprepared = fmt::detail::compile<int>(L"4{}");
+  fmt::format_to(ws.begin(), wprepared, 2);
+  EXPECT_EQ(L"42", ws);
+}
+
+TEST(CompileTest, FormatToN) {
+  char buf[5];
+  auto f = fmt::detail::compile<int>("{:10}");
+  auto result = fmt::format_to_n(buf, 5, f, 42);
+  EXPECT_EQ(result.size, 10);
+  EXPECT_EQ(result.out, buf + 5);
+  EXPECT_EQ(fmt::string_view(buf, 5), "     ");
+}
+
+TEST(CompileTest, FormattedSize) {
+  auto f = fmt::detail::compile<int>("{:10}");
+  EXPECT_EQ(fmt::formatted_size(f, 42), 10);
+}
+
+TEST(CompileTest, MultipleTypes) {
+  auto f = fmt::detail::compile<int, int>("{} {}");
+  EXPECT_EQ(fmt::format(f, 42, 42), "42 42");
+}
+
+struct test_formattable {};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<test_formattable> : formatter<const char*> {
+  template <typename FormatContext>
+  auto format(test_formattable, FormatContext& ctx) -> decltype(ctx.out()) {
+    return formatter<const char*>::format("foo", ctx);
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(CompileTest, FormatUserDefinedType) {
+  auto f = fmt::detail::compile<test_formattable>("{}");
+  EXPECT_EQ(fmt::format(f, test_formattable()), "foo");
+}
+
+TEST(CompileTest, EmptyFormatString) {
+  auto f = fmt::detail::compile<>("");
+  EXPECT_EQ(fmt::format(f), "");
+}
+
+#ifdef __cpp_if_constexpr
+TEST(CompileTest, FormatDefault) {
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42));
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42u));
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42ll));
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42ull));
+  EXPECT_EQ("true", fmt::format(FMT_COMPILE("{}"), true));
+  EXPECT_EQ("x", fmt::format(FMT_COMPILE("{}"), 'x'));
+  EXPECT_EQ("4.2", fmt::format(FMT_COMPILE("{}"), 4.2));
+  EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), "foo"));
+  EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), std::string("foo")));
+  EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), test_formattable()));
+}
+
+TEST(CompileTest, FormatWideString) {
+  EXPECT_EQ(L"42", fmt::format(FMT_COMPILE(L"{}"), 42));
+}
+
+TEST(CompileTest, FormatSpecs) {
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{:x}"), 0x42));
+}
+
+TEST(CompileTest, DynamicWidth) {
+  EXPECT_EQ("  42foo  ",
+            fmt::format(FMT_COMPILE("{:{}}{:{}}"), 42, 4, "foo", 5));
+}
+
+TEST(CompileTest, FormatTo) {
+  char buf[8];
+  auto end = fmt::format_to(buf, FMT_COMPILE("{}"), 42);
+  *end = '\0';
+  EXPECT_STREQ("42", buf);
+  end = fmt::format_to(buf, FMT_COMPILE("{:x}"), 42);
+  *end = '\0';
+  EXPECT_STREQ("2a", buf);
+}
+
+TEST(CompileTest, FormatToNWithCompileMacro) {
+  constexpr auto buffer_size = 8;
+  char buffer[buffer_size];
+  auto res = fmt::format_to_n(buffer, buffer_size, FMT_COMPILE("{}"), 42);
+  *res.out = '\0';
+  EXPECT_STREQ("42", buffer);
+  res = fmt::format_to_n(buffer, buffer_size, FMT_COMPILE("{:x}"), 42);
+  *res.out = '\0';
+  EXPECT_STREQ("2a", buffer);
+}
+
+TEST(CompileTest, TextAndArg) {
+  EXPECT_EQ(">>>42<<<", fmt::format(FMT_COMPILE(">>>{}<<<"), 42));
+  EXPECT_EQ("42!", fmt::format(FMT_COMPILE("{}!"), 42));
+}
+#endif

test/core-test.cc

@@ -11,17 +11,16 @@
 #include <functional>
 #include <iterator>
 #include <limits>
+#include <memory>
 #include <string>
 #include <type_traits>
-#include <memory>
-
-#include "test-assert.h"
 
 #include "gmock.h"
+#include "test-assert.h"
 
 // Check if fmt/core.h compiles with windows.h included before it.
 #ifdef _WIN32
-# include <windows.h>
+#  include <windows.h>
 #endif
 
 #include "fmt/core.h"
@@ -30,36 +29,27 @@
 #undef max
 
 using fmt::basic_format_arg;
-using fmt::internal::basic_buffer;
-using fmt::internal::value;
 using fmt::string_view;
+using fmt::detail::buffer;
+using fmt::detail::make_arg;
+using fmt::detail::value;
 
 using testing::_;
+using testing::Invoke;
+using testing::Return;
 using testing::StrictMock;
 
-namespace {
-
 struct test_struct {};
 
-template <typename Context, typename T>
-basic_format_arg<Context> make_arg(const T &value) {
-  return fmt::internal::make_arg<Context>(value);
-}
-}  // namespace
-
 FMT_BEGIN_NAMESPACE
-template <typename Char>
-struct formatter<test_struct, Char> {
+template <typename Char> struct formatter<test_struct, Char> {
   template <typename ParseContext>
-  auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
+  auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
     return ctx.begin();
   }
 
-  typedef std::back_insert_iterator<basic_buffer<Char>> iterator;
-
-  auto format(test_struct, basic_format_context<iterator, char> &ctx)
-      -> decltype(ctx.out()) {
-    const Char *test = "test";
+  auto format(test_struct, format_context& ctx) -> decltype(ctx.out()) {
+    const Char* test = "test";
     return std::copy_n(test, std::strlen(test), ctx.out());
   }
 };
@@ -67,46 +57,44 @@ FMT_END_NAMESPACE
 
 #if !FMT_GCC_VERSION || FMT_GCC_VERSION >= 470
 TEST(BufferTest, Noncopyable) {
-  EXPECT_FALSE(std::is_copy_constructible<basic_buffer<char> >::value);
-#if !FMT_MSC_VER
+  EXPECT_FALSE(std::is_copy_constructible<buffer<char>>::value);
+#  if !FMT_MSC_VER
   // std::is_copy_assignable is broken in MSVC2013.
-  EXPECT_FALSE(std::is_copy_assignable<basic_buffer<char> >::value);
-#endif
+  EXPECT_FALSE(std::is_copy_assignable<buffer<char>>::value);
+#  endif
 }
 
 TEST(BufferTest, Nonmoveable) {
-  EXPECT_FALSE(std::is_move_constructible<basic_buffer<char> >::value);
-#if !FMT_MSC_VER
+  EXPECT_FALSE(std::is_move_constructible<buffer<char>>::value);
+#  if !FMT_MSC_VER
   // std::is_move_assignable is broken in MSVC2013.
-  EXPECT_FALSE(std::is_move_assignable<basic_buffer<char> >::value);
-#endif
+  EXPECT_FALSE(std::is_move_assignable<buffer<char>>::value);
+#  endif
 }
 #endif
 
-// A test buffer with a dummy grow method.
-template <typename T>
-struct test_buffer : basic_buffer<T> {
-  void grow(std::size_t capacity) { this->set(FMT_NULL, capacity); }
-};
+TEST(BufferTest, Indestructible) {
+  static_assert(!std::is_destructible<fmt::detail::buffer<int>>(),
+                "buffer's destructor is protected");
+}
 
-template <typename T>
-struct mock_buffer : basic_buffer<T> {
-  MOCK_METHOD1(do_grow, void (std::size_t capacity));
+template <typename T> struct mock_buffer final : buffer<T> {
+  MOCK_METHOD1(do_grow, size_t(size_t capacity));
 
-  void grow(std::size_t capacity) {
-    this->set(this->data(), capacity);
-    do_grow(capacity);
+  void grow(size_t capacity) { this->set(this->data(), do_grow(capacity)); }
+
+  mock_buffer(T* data = nullptr, size_t capacity = 0) {
+    this->set(data, capacity);
+    ON_CALL(*this, do_grow(_)).WillByDefault(Invoke([](size_t capacity) {
+      return capacity;
+    }));
   }
-
-  mock_buffer() {}
-  mock_buffer(T *data) { this->set(data, 0); }
-  mock_buffer(T *data, std::size_t capacity) { this->set(data, capacity); }
 };
 
 TEST(BufferTest, Ctor) {
   {
     mock_buffer<int> buffer;
-    EXPECT_EQ(FMT_NULL, &buffer[0]);
+    EXPECT_EQ(nullptr, buffer.data());
     EXPECT_EQ(static_cast<size_t>(0), buffer.size());
     EXPECT_EQ(static_cast<size_t>(0), buffer.capacity());
   }
@@ -119,7 +107,7 @@ TEST(BufferTest, Ctor) {
   }
   {
     int dummy;
-    std::size_t capacity = std::numeric_limits<std::size_t>::max();
+    size_t capacity = std::numeric_limits<size_t>::max();
     mock_buffer<int> buffer(&dummy, capacity);
     EXPECT_EQ(&dummy, &buffer[0]);
     EXPECT_EQ(static_cast<size_t>(0), buffer.size());
@@ -127,19 +115,6 @@ TEST(BufferTest, Ctor) {
   }
 }
 
-struct dying_buffer : test_buffer<int> {
-  MOCK_METHOD0(die, void());
-  ~dying_buffer() { die(); }
-};
-
-TEST(BufferTest, VirtualDtor) {
-  typedef StrictMock<dying_buffer> stict_mock_buffer;
-  stict_mock_buffer *mock_buffer = new stict_mock_buffer();
-  EXPECT_CALL(*mock_buffer, die());
-  basic_buffer<int> *buffer = mock_buffer;
-  delete buffer;
-}
-
 TEST(BufferTest, Access) {
   char data[10];
   mock_buffer<char> buffer(data, sizeof(data));
@@ -147,34 +122,44 @@ TEST(BufferTest, Access) {
   EXPECT_EQ(11, buffer[0]);
   buffer[3] = 42;
   EXPECT_EQ(42, *(&buffer[0] + 3));
-  const basic_buffer<char> &const_buffer = buffer;
+  const fmt::detail::buffer<char>& const_buffer = buffer;
   EXPECT_EQ(42, const_buffer[3]);
 }
 
-TEST(BufferTest, Resize) {
+TEST(BufferTest, TryResize) {
   char data[123];
   mock_buffer<char> buffer(data, sizeof(data));
   buffer[10] = 42;
   EXPECT_EQ(42, buffer[10]);
-  buffer.resize(20);
+  buffer.try_resize(20);
   EXPECT_EQ(20u, buffer.size());
   EXPECT_EQ(123u, buffer.capacity());
   EXPECT_EQ(42, buffer[10]);
-  buffer.resize(5);
+  buffer.try_resize(5);
   EXPECT_EQ(5u, buffer.size());
   EXPECT_EQ(123u, buffer.capacity());
   EXPECT_EQ(42, buffer[10]);
-  // Check if resize calls grow.
+  // Check if try_resize calls grow.
   EXPECT_CALL(buffer, do_grow(124));
-  buffer.resize(124);
+  buffer.try_resize(124);
   EXPECT_CALL(buffer, do_grow(200));
-  buffer.resize(200);
+  buffer.try_resize(200);
+}
+
+TEST(BufferTest, TryResizePartial) {
+  char data[10];
+  mock_buffer<char> buffer(data, sizeof(data));
+  EXPECT_CALL(buffer, do_grow(20)).WillOnce(Return(15));
+  buffer.try_resize(20);
+  EXPECT_EQ(buffer.capacity(), 15);
+  EXPECT_EQ(buffer.size(), 15);
 }
 
 TEST(BufferTest, Clear) {
-  test_buffer<char> buffer;
-  buffer.resize(20);
-  buffer.resize(0);
+  mock_buffer<char> buffer;
+  EXPECT_CALL(buffer, do_grow(20));
+  buffer.try_resize(20);
+  buffer.try_resize(0);
   EXPECT_EQ(static_cast<size_t>(0), buffer.size());
   EXPECT_EQ(20u, buffer.capacity());
 }
@@ -182,11 +167,11 @@ TEST(BufferTest, Clear) {
 TEST(BufferTest, Append) {
   char data[15];
   mock_buffer<char> buffer(data, 10);
-  const char *test = "test";
+  auto test = "test";
   buffer.append(test, test + 5);
   EXPECT_STREQ(test, &buffer[0]);
   EXPECT_EQ(5u, buffer.size());
-  buffer.resize(10);
+  buffer.try_resize(10);
   EXPECT_CALL(buffer, do_grow(12));
   buffer.append(test, test + 2);
   EXPECT_EQ('t', buffer[10]);
@@ -194,95 +179,101 @@ TEST(BufferTest, Append) {
   EXPECT_EQ(12u, buffer.size());
 }
 
+TEST(BufferTest, AppendPartial) {
+  char data[10];
+  mock_buffer<char> buffer(data, sizeof(data));
+  testing::InSequence seq;
+  EXPECT_CALL(buffer, do_grow(15)).WillOnce(Return(10));
+  EXPECT_CALL(buffer, do_grow(15)).WillOnce(Invoke([&buffer](size_t) {
+    EXPECT_EQ(fmt::string_view(buffer.data(), buffer.size()), "0123456789");
+    buffer.clear();
+    return 10;
+  }));
+  auto test = "0123456789abcde";
+  buffer.append(test, test + 15);
+}
+
 TEST(BufferTest, AppendAllocatesEnoughStorage) {
   char data[19];
   mock_buffer<char> buffer(data, 10);
-  const char *test = "abcdefgh";
-  buffer.resize(10);
+  auto test = "abcdefgh";
+  buffer.try_resize(10);
   EXPECT_CALL(buffer, do_grow(19));
   buffer.append(test, test + 9);
 }
 
 TEST(ArgTest, FormatArgs) {
-  fmt::format_args args;
+  auto args = fmt::format_args();
   EXPECT_FALSE(args.get(1));
 }
 
 struct custom_context {
-  typedef char char_type;
+  using char_type = char;
+  using parse_context_type = fmt::format_parse_context;
 
-  template <typename T>
-  struct formatter_type {
-    struct type {
-      template <typename ParseContext>
-      auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
-        return ctx.begin();
-      }
+  template <typename T> struct formatter_type {
+    template <typename ParseContext>
+    auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+      return ctx.begin();
+    }
 
-      const char *format(const T &, custom_context& ctx) {
-        ctx.called = true;
-        return FMT_NULL;
-      }
-    };
+    const char* format(const T&, custom_context& ctx) {
+      ctx.called = true;
+      return nullptr;
+    }
   };
 
   bool called;
+  fmt::format_parse_context ctx;
 
-  fmt::format_parse_context parse_context() {
-    return fmt::format_parse_context("");
-  }
-  void advance_to(const char *) {}
+  fmt::format_parse_context& parse_context() { return ctx; }
+  void advance_to(const char*) {}
 };
 
 TEST(ArgTest, MakeValueWithCustomContext) {
-  test_struct t;
-  fmt::internal::value<custom_context> arg =
-      fmt::internal::make_value<custom_context>(t);
-  custom_context ctx = {false};
-  arg.custom.format(&t, ctx);
+  auto t = test_struct();
+  fmt::detail::value<custom_context> arg(
+      fmt::detail::arg_mapper<custom_context>().map(t));
+  custom_context ctx = {false, fmt::format_parse_context("")};
+  arg.custom.format(&t, ctx.parse_context(), ctx);
   EXPECT_TRUE(ctx.called);
 }
 
 FMT_BEGIN_NAMESPACE
-namespace internal {
+namespace detail {
 template <typename Char>
 bool operator==(custom_value<Char> lhs, custom_value<Char> rhs) {
   return lhs.value == rhs.value;
 }
-}
+}  // namespace detail
 FMT_END_NAMESPACE
 
 // Use a unique result type to make sure that there are no undesirable
 // conversions.
 struct test_result {};
 
-template <typename T>
-struct mock_visitor {
-  template <typename U>
-  struct result { typedef test_result type; };
+template <typename T> struct mock_visitor {
+  template <typename U> struct result { using type = test_result; };
 
   mock_visitor() {
-    ON_CALL(*this, visit(_)).WillByDefault(testing::Return(test_result()));
+    ON_CALL(*this, visit(_)).WillByDefault(Return(test_result()));
   }
 
-  MOCK_METHOD1_T(visit, test_result (T value));
-  MOCK_METHOD0_T(unexpected, void ());
+  MOCK_METHOD1_T(visit, test_result(T value));
+  MOCK_METHOD0_T(unexpected, void());
 
   test_result operator()(T value) { return visit(value); }
 
-  template <typename U>
-  test_result operator()(U) {
+  template <typename U> test_result operator()(U) {
     unexpected();
     return test_result();
   }
 };
 
-template <typename T>
-struct visit_type { typedef T Type; };
+template <typename T> struct visit_type { using type = T; };
 
-#define VISIT_TYPE(Type_, visit_type_) \
-  template <> \
-  struct visit_type<Type_> { typedef visit_type_ Type; }
+#define VISIT_TYPE(type_, visit_type_) \
+  template <> struct visit_type<type_> { using type = visit_type_; }
 
 VISIT_TYPE(signed char, int);
 VISIT_TYPE(unsigned char, unsigned);
@@ -297,40 +288,38 @@ VISIT_TYPE(long, long long);
 VISIT_TYPE(unsigned long, unsigned long long);
 #endif
 
-VISIT_TYPE(float, double);
+#define CHECK_ARG_(Char, expected, value)                                     \
+  {                                                                           \
+    testing::StrictMock<mock_visitor<decltype(expected)>> visitor;            \
+    EXPECT_CALL(visitor, visit(expected));                                    \
+    using iterator = std::back_insert_iterator<buffer<Char>>;                 \
+    fmt::visit_format_arg(                                                    \
+        visitor, make_arg<fmt::basic_format_context<iterator, Char>>(value)); \
+  }
 
-#define CHECK_ARG_(Char, expected, value) { \
-  testing::StrictMock<mock_visitor<decltype(expected)>> visitor; \
-  EXPECT_CALL(visitor, visit(expected)); \
-  typedef std::back_insert_iterator<basic_buffer<Char>> iterator; \
-  fmt::visit(visitor, \
-      make_arg<fmt::basic_format_context<iterator, Char>>(value)); \
-}
+#define CHECK_ARG(value, typename_)                          \
+  {                                                          \
+    using value_type = decltype(value);                      \
+    typename_ visit_type<value_type>::type expected = value; \
+    CHECK_ARG_(char, expected, value)                        \
+    CHECK_ARG_(wchar_t, expected, value)                     \
+  }
 
-#define CHECK_ARG(value, typename_) { \
-  typedef decltype(value) value_type; \
-  typename_ visit_type<value_type>::Type expected = value; \
-  CHECK_ARG_(char, expected, value) \
-  CHECK_ARG_(wchar_t, expected, value) \
-}
+template <typename T> class NumericArgTest : public testing::Test {};
+
+using types =
+    ::testing::Types<bool, signed char, unsigned char, signed, unsigned short,
+                     int, unsigned, long, unsigned long, long long,
+                     unsigned long long, float, double, long double>;
+TYPED_TEST_CASE(NumericArgTest, types);
 
 template <typename T>
-class NumericArgTest : public testing::Test {};
-
-typedef ::testing::Types<
-  bool, signed char, unsigned char, signed, unsigned short,
-  int, unsigned, long, unsigned long, long long, unsigned long long,
-  float, double, long double> Types;
-TYPED_TEST_CASE(NumericArgTest, Types);
-
-template <typename T>
-typename std::enable_if<std::is_integral<T>::value, T>::type test_value() {
+fmt::enable_if_t<std::is_integral<T>::value, T> test_value() {
   return static_cast<T>(42);
 }
 
 template <typename T>
-typename std::enable_if<std::is_floating_point<T>::value, T>::type
-    test_value() {
+fmt::enable_if_t<std::is_floating_point<T>::value, T> test_value() {
   return static_cast<T>(4.2);
 }
 
@@ -348,18 +337,18 @@ TEST(ArgTest, CharArg) {
 
 TEST(ArgTest, StringArg) {
   char str_data[] = "test";
-  char *str = str_data;
-  const char *cstr = str;
+  char* str = str_data;
+  const char* cstr = str;
   CHECK_ARG_(char, cstr, str);
 
-  string_view sref(str);
+  auto sref = string_view(str);
   CHECK_ARG_(char, sref, std::string(str));
 }
 
 TEST(ArgTest, WStringArg) {
   wchar_t str_data[] = L"test";
-  wchar_t *str = str_data;
-  const wchar_t *cstr = str;
+  wchar_t* str = str_data;
+  const wchar_t* cstr = str;
 
   fmt::wstring_view sref(str);
   CHECK_ARG_(wchar_t, cstr, str);
@@ -369,8 +358,8 @@ TEST(ArgTest, WStringArg) {
 }
 
 TEST(ArgTest, PointerArg) {
-  void *p = FMT_NULL;
-  const void *cp = FMT_NULL;
+  void* p = nullptr;
+  const void* cp = nullptr;
   CHECK_ARG_(char, cp, p);
   CHECK_ARG_(wchar_t, cp, p);
   CHECK_ARG(cp, );
@@ -379,14 +368,15 @@ TEST(ArgTest, PointerArg) {
 struct check_custom {
   test_result operator()(
       fmt::basic_format_arg<fmt::format_context>::handle h) const {
-    struct test_buffer : fmt::internal::basic_buffer<char> {
+    struct test_buffer final : fmt::detail::buffer<char> {
       char data[10];
-      test_buffer() : fmt::internal::basic_buffer<char>(data, 0, 10) {}
-      void grow(std::size_t) {}
+      test_buffer() : fmt::detail::buffer<char>(data, 0, 10) {}
+      void grow(size_t) {}
     } buffer;
-    fmt::internal::basic_buffer<char> &base = buffer;
-    fmt::format_context ctx(std::back_inserter(base), "", fmt::format_args());
-    h.format(ctx);
+    fmt::format_parse_context parse_ctx("");
+    fmt::format_context ctx{fmt::detail::buffer_appender<char>(buffer),
+                            fmt::format_args()};
+    h.format(parse_ctx, ctx);
     EXPECT_EQ("test", std::string(buffer.data, buffer.size()));
     return test_result();
   }
@@ -394,34 +384,190 @@ struct check_custom {
 
 TEST(ArgTest, CustomArg) {
   test_struct test;
-  typedef mock_visitor<fmt::basic_format_arg<fmt::format_context>::handle>
-    visitor;
+  using visitor =
+      mock_visitor<fmt::basic_format_arg<fmt::format_context>::handle>;
   testing::StrictMock<visitor> v;
-  EXPECT_CALL(v, visit(_)).WillOnce(testing::Invoke(check_custom()));
-  fmt::visit(v, make_arg<fmt::format_context>(test));
+  EXPECT_CALL(v, visit(_)).WillOnce(Invoke(check_custom()));
+  fmt::visit_format_arg(v, make_arg<fmt::format_context>(test));
 }
 
 TEST(ArgTest, VisitInvalidArg) {
-  testing::StrictMock< mock_visitor<fmt::monostate> > visitor;
+  testing::StrictMock<mock_visitor<fmt::monostate>> visitor;
   EXPECT_CALL(visitor, visit(_));
   fmt::basic_format_arg<fmt::format_context> arg;
-  visit(visitor, arg);
+  fmt::visit_format_arg(visitor, arg);
+}
+
+TEST(FormatDynArgsTest, Basic) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  store.push_back(42);
+  store.push_back("abc1");
+  store.push_back(1.5f);
+  EXPECT_EQ("42 and abc1 and 1.5", fmt::vformat("{} and {} and {}", store));
+}
+
+TEST(FormatDynArgsTest, StringsAndRefs) {
+  // Unfortunately the tests are compiled with old ABI so strings use COW.
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  char str[] = "1234567890";
+  store.push_back(str);
+  store.push_back(std::cref(str));
+  store.push_back(fmt::string_view{str});
+  str[0] = 'X';
+
+  std::string result = fmt::vformat("{} and {} and {}", store);
+  EXPECT_EQ("1234567890 and X234567890 and X234567890", result);
+}
+
+struct custom_type {
+  int i = 0;
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<custom_type> {
+  auto parse(format_parse_context& ctx) const -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const custom_type& p, FormatContext& ctx) -> decltype(ctx.out()) {
+    return format_to(ctx.out(), "cust={}", p.i);
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(FormatDynArgsTest, CustomFormat) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  custom_type c{};
+  store.push_back(c);
+  ++c.i;
+  store.push_back(c);
+  ++c.i;
+  store.push_back(std::cref(c));
+  ++c.i;
+  std::string result = fmt::vformat("{} and {} and {}", store);
+  EXPECT_EQ("cust=0 and cust=1 and cust=3", result);
+}
+
+TEST(FormatDynArgsTest, NamedInt) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  store.push_back(fmt::arg("a1", 42));
+  EXPECT_EQ("42", fmt::vformat("{a1}", store));
+}
+
+TEST(FormatDynArgsTest, NamedStrings) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  char str[]{"1234567890"};
+  store.push_back(fmt::arg("a1", str));
+  store.push_back(fmt::arg("a2", std::cref(str)));
+  str[0] = 'X';
+  EXPECT_EQ("1234567890 and X234567890", fmt::vformat("{a1} and {a2}", store));
+}
+
+TEST(FormatDynArgsTest, NamedArgByRef) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+
+  // Note: fmt::arg() constructs an object which holds a reference
+  // to its value. It's not an aggregate, so it doesn't extend the
+  // reference lifetime. As a result, it's a very bad idea passing temporary
+  // as a named argument value. Only GCC with optimization level >0
+  // complains about this.
+  //
+  // A real life usecase is when you have both name and value alive
+  // guarantee their lifetime and thus don't want them to be copied into
+  // storages.
+  int a1_val{42};
+  auto a1 = fmt::arg("a1_", a1_val);
+  store.push_back("abc");
+  store.push_back(1.5f);
+  store.push_back(std::cref(a1));
+
+  std::string result = fmt::vformat("{a1_} and {} and {} and {}", store);
+  EXPECT_EQ("42 and abc and 1.5 and 42", result);
+}
+
+TEST(FormatDynArgsTest, NamedCustomFormat) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  custom_type c{};
+  store.push_back(fmt::arg("c1", c));
+  ++c.i;
+  store.push_back(fmt::arg("c2", c));
+  ++c.i;
+  store.push_back(fmt::arg("c_ref", std::cref(c)));
+  ++c.i;
+  std::string result = fmt::vformat("{c1} and {c2} and {c_ref}", store);
+  EXPECT_EQ("cust=0 and cust=1 and cust=3", result);
+}
+
+TEST(FormatDynArgsTest, Clear) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  store.push_back(42);
+
+  std::string result = fmt::vformat("{}", store);
+  EXPECT_EQ("42", result);
+
+  store.push_back(43);
+  result = fmt::vformat("{} and {}", store);
+  EXPECT_EQ("42 and 43", result);
+
+  store.clear();
+  store.push_back(44);
+  result = fmt::vformat("{}", store);
+  EXPECT_EQ("44", result);
+}
+
+TEST(FormatDynArgsTest, Reserve) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  store.reserve(2, 1);
+  store.push_back(1.5f);
+  store.push_back(fmt::arg("a1", 42));
+  std::string result = fmt::vformat("{a1} and {}", store);
+  EXPECT_EQ("42 and 1.5", result);
+}
+
+struct copy_throwable {
+  copy_throwable() {}
+  copy_throwable(const copy_throwable&) { throw "deal with it"; }
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<copy_throwable> {
+  auto parse(format_parse_context& ctx) const -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+  auto format(copy_throwable, format_context& ctx) -> decltype(ctx.out()) {
+    return ctx.out();
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(FormatDynArgsTest, ThrowOnCopy) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  store.push_back(std::string("foo"));
+  try {
+    store.push_back(copy_throwable());
+  } catch (...) {
+  }
+  EXPECT_EQ(fmt::vformat("{}", store), "foo");
+}
+
+TEST(StringViewTest, ValueType) {
+  static_assert(std::is_same<string_view::value_type, char>::value, "");
 }
 
 TEST(StringViewTest, Length) {
-  // Test that StringRef::size() returns string length, not buffer size.
+  // Test that string_view::size() returns string length, not buffer size.
   char str[100] = "some string";
   EXPECT_EQ(std::strlen(str), string_view(str).size());
   EXPECT_LT(std::strlen(str), sizeof(str));
 }
 
 // Check string_view's comparison operator.
-template <template <typename> class Op>
-void check_op() {
-  const char *inputs[] = {"foo", "fop", "fo"};
-  std::size_t num_inputs = sizeof(inputs) / sizeof(*inputs);
-  for (std::size_t i = 0; i < num_inputs; ++i) {
-    for (std::size_t j = 0; j < num_inputs; ++j) {
+template <template <typename> class Op> void check_op() {
+  const char* inputs[] = {"foo", "fop", "fo"};
+  size_t num_inputs = sizeof(inputs) / sizeof(*inputs);
+  for (size_t i = 0; i < num_inputs; ++i) {
+    for (size_t j = 0; j < num_inputs; ++j) {
       string_view lhs(inputs[i]), rhs(inputs[j]);
       EXPECT_EQ(Op<int>()(lhs.compare(rhs), 0), Op<string_view>()(lhs, rhs));
     }
@@ -442,63 +588,88 @@ TEST(StringViewTest, Compare) {
   check_op<std::greater_equal>();
 }
 
-enum basic_enum {};
+struct enabled_formatter {};
+struct disabled_formatter {};
+struct disabled_formatter_convertible {
+  operator int() const { return 42; }
+};
 
-TEST(CoreTest, ConvertToInt) {
-  EXPECT_FALSE((fmt::convert_to_int<char, char>::value));
-  EXPECT_FALSE((fmt::convert_to_int<const char *, char>::value));
-  EXPECT_TRUE((fmt::convert_to_int<basic_enum, char>::value));
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<enabled_formatter> {
+  auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+  auto format(enabled_formatter, format_context& ctx) -> decltype(ctx.out()) {
+    return ctx.out();
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(CoreTest, HasFormatter) {
+  using fmt::has_formatter;
+  using context = fmt::format_context;
+  static_assert(has_formatter<enabled_formatter, context>::value, "");
+  static_assert(!has_formatter<disabled_formatter, context>::value, "");
+  static_assert(!has_formatter<disabled_formatter_convertible, context>::value,
+                "");
 }
 
-enum enum_with_underlying_type : char {};
+struct convertible_to_int {
+  operator int() const { return 42; }
+};
 
-TEST(CoreTest, IsEnumConvertibleToInt) {
-  EXPECT_TRUE((fmt::convert_to_int<enum_with_underlying_type, char>::value));
+struct convertible_to_c_string {
+  operator const char*() const { return "foo"; }
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<convertible_to_int> {
+  auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+  auto format(convertible_to_int, format_context& ctx) -> decltype(ctx.out()) {
+    return std::copy_n("foo", 3, ctx.out());
+  }
+};
+
+template <> struct formatter<convertible_to_c_string> {
+  auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+  auto format(convertible_to_c_string, format_context& ctx)
+      -> decltype(ctx.out()) {
+    return std::copy_n("bar", 3, ctx.out());
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(CoreTest, FormatterOverridesImplicitConversion) {
+  EXPECT_EQ(fmt::format("{}", convertible_to_int()), "foo");
+  EXPECT_EQ(fmt::format("{}", convertible_to_c_string()), "bar");
 }
 
 namespace my_ns {
-template <typename Char>
-class my_string {
- public:
-  my_string(const Char *s) : s_(s) {}
-  const Char * data() const FMT_NOEXCEPT { return s_.data(); }
-  std::size_t length() const FMT_NOEXCEPT { return s_.size(); }
-  operator const Char*() const { return s_.c_str(); }
+template <typename Char> class my_string {
  private:
   std::basic_string<Char> s_;
+
+ public:
+  my_string(const Char* s) : s_(s) {}
+  const Char* data() const FMT_NOEXCEPT { return s_.data(); }
+  size_t length() const FMT_NOEXCEPT { return s_.size(); }
+  operator const Char*() const { return s_.c_str(); }
 };
 
 template <typename Char>
-inline fmt::basic_string_view<Char>
-    to_string_view(const my_string<Char> &s) FMT_NOEXCEPT {
-  return { s.data(), s.length() };
+inline fmt::basic_string_view<Char> to_string_view(const my_string<Char>& s)
+    FMT_NOEXCEPT {
+  return {s.data(), s.length()};
 }
 
 struct non_string {};
-}
+}  // namespace my_ns
 
-namespace FakeQt {
-class QString {
- public:
-  QString(const wchar_t *s) : s_(std::make_shared<std::wstring>(s)) {}
-  const wchar_t *utf16() const FMT_NOEXCEPT { return s_->data(); }
-  int size() const FMT_NOEXCEPT { return static_cast<int>(s_->size()); }
-#ifdef FMT_STRING_VIEW
-  operator FMT_STRING_VIEW<wchar_t>() const FMT_NOEXCEPT { return *s_; }
-#endif
- private:
-  std::shared_ptr<std::wstring> s_;
-};
-
-inline fmt::basic_string_view<wchar_t> to_string_view(
-    const QString &s) FMT_NOEXCEPT {
-  return {s.utf16(),
-          static_cast<std::size_t>(s.size())};
-}
-}
-
-template <typename T>
-class IsStringTest : public testing::Test {};
+template <typename T> class IsStringTest : public testing::Test {};
 
 typedef ::testing::Types<char, wchar_t, char16_t, char32_t> StringCharTypes;
 TYPED_TEST_CASE(IsStringTest, StringCharTypes);
@@ -506,30 +677,28 @@ TYPED_TEST_CASE(IsStringTest, StringCharTypes);
 namespace {
 template <typename Char>
 struct derived_from_string_view : fmt::basic_string_view<Char> {};
-}
+}  // namespace
 
 TYPED_TEST(IsStringTest, IsString) {
-  EXPECT_TRUE((fmt::internal::is_string<TypeParam *>::value));
-  EXPECT_TRUE((fmt::internal::is_string<const TypeParam *>::value));
-  EXPECT_TRUE((fmt::internal::is_string<TypeParam[2]>::value));
-  EXPECT_TRUE((fmt::internal::is_string<const TypeParam[2]>::value));
-  EXPECT_TRUE((fmt::internal::is_string<std::basic_string<TypeParam>>::value));
+  EXPECT_TRUE(fmt::detail::is_string<TypeParam*>::value);
+  EXPECT_TRUE(fmt::detail::is_string<const TypeParam*>::value);
+  EXPECT_TRUE(fmt::detail::is_string<TypeParam[2]>::value);
+  EXPECT_TRUE(fmt::detail::is_string<const TypeParam[2]>::value);
+  EXPECT_TRUE(fmt::detail::is_string<std::basic_string<TypeParam>>::value);
+  EXPECT_TRUE(fmt::detail::is_string<fmt::basic_string_view<TypeParam>>::value);
   EXPECT_TRUE(
-        (fmt::internal::is_string<fmt::basic_string_view<TypeParam>>::value));
-  EXPECT_TRUE(
-        (fmt::internal::is_string<derived_from_string_view<TypeParam>>::value));
-#ifdef FMT_STRING_VIEW
-  EXPECT_TRUE((fmt::internal::is_string<FMT_STRING_VIEW<TypeParam>>::value));
-#endif
-  EXPECT_TRUE((fmt::internal::is_string<my_ns::my_string<TypeParam>>::value));
-  EXPECT_FALSE((fmt::internal::is_string<my_ns::non_string>::value));
-  EXPECT_TRUE((fmt::internal::is_string<FakeQt::QString>::value));
+      fmt::detail::is_string<derived_from_string_view<TypeParam>>::value);
+  using string_view = fmt::detail::std_string_view<TypeParam>;
+  EXPECT_TRUE(std::is_empty<string_view>::value !=
+              fmt::detail::is_string<string_view>::value);
+  EXPECT_TRUE(fmt::detail::is_string<my_ns::my_string<TypeParam>>::value);
+  EXPECT_FALSE(fmt::detail::is_string<my_ns::non_string>::value);
 }
 
 TEST(CoreTest, Format) {
   // This should work without including fmt/format.h.
 #ifdef FMT_FORMAT_H_
-# error fmt/format.h must not be included in the core test
+#  error fmt/format.h must not be included in the core test
 #endif
   EXPECT_EQ(fmt::format("{}", 42), "42");
 }
@@ -537,7 +706,7 @@ TEST(CoreTest, Format) {
 TEST(CoreTest, FormatTo) {
   // This should work without including fmt/format.h.
 #ifdef FMT_FORMAT_H_
-# error fmt/format.h must not be included in the core test
+#  error fmt/format.h must not be included in the core test
 #endif
   std::string s;
   fmt::format_to(std::back_inserter(s), "{}", 42);
@@ -546,68 +715,59 @@ TEST(CoreTest, FormatTo) {
 
 TEST(CoreTest, ToStringViewForeignStrings) {
   using namespace my_ns;
-  using namespace FakeQt;
   EXPECT_EQ(to_string_view(my_string<char>("42")), "42");
-  EXPECT_EQ(to_string_view(my_string<wchar_t>(L"42")), L"42");
-  EXPECT_EQ(to_string_view(QString(L"42")), L"42");
-  fmt::internal::type type =
-      fmt::internal::get_type<fmt::format_context, my_string<char>>::value;
-  EXPECT_EQ(type, fmt::internal::string_type);
-  type =
-      fmt::internal::get_type<fmt::wformat_context, my_string<wchar_t>>::value;
-  EXPECT_EQ(type, fmt::internal::string_type);
-  type = fmt::internal::get_type<fmt::wformat_context, QString>::value;
-  EXPECT_EQ(type, fmt::internal::string_type);
-  // Does not compile: only wide format contexts are compatible with QString!
-  // type = fmt::internal::get_type<fmt::format_context, QString>::value;
+  fmt::detail::type type =
+      fmt::detail::mapped_type_constant<my_string<char>,
+                                        fmt::format_context>::value;
+  EXPECT_EQ(type, fmt::detail::type::string_type);
 }
 
 TEST(CoreTest, FormatForeignStrings) {
   using namespace my_ns;
-  using namespace FakeQt;
   EXPECT_EQ(fmt::format(my_string<char>("{}"), 42), "42");
-  EXPECT_EQ(fmt::format(my_string<wchar_t>(L"{}"), 42), L"42");
-  EXPECT_EQ(fmt::format(QString(L"{}"), 42), L"42");
-  EXPECT_EQ(fmt::format(QString(L"{}"), my_string<wchar_t>(L"42")), L"42");
-  EXPECT_EQ(fmt::format(my_string<wchar_t>(L"{}"), QString(L"42")), L"42");
 }
 
+struct implicitly_convertible_to_string {
+  operator std::string() const { return "foo"; }
+};
+
 struct implicitly_convertible_to_string_view {
   operator fmt::string_view() const { return "foo"; }
 };
 
-TEST(FormatterTest, FormatImplicitlyConvertibleToStringView) {
+TEST(CoreTest, FormatImplicitlyConvertibleToStringView) {
   EXPECT_EQ("foo", fmt::format("{}", implicitly_convertible_to_string_view()));
 }
 
 // std::is_constructible is broken in MSVC until version 2015.
-#if FMT_USE_EXPLICIT && (!FMT_MSC_VER || FMT_MSC_VER >= 1900)
+#if !FMT_MSC_VER || FMT_MSC_VER >= 1900
 struct explicitly_convertible_to_string_view {
   explicit operator fmt::string_view() const { return "foo"; }
 };
 
-TEST(FormatterTest, FormatExplicitlyConvertibleToStringView) {
+TEST(CoreTest, FormatExplicitlyConvertibleToStringView) {
   EXPECT_EQ("foo", fmt::format("{}", explicitly_convertible_to_string_view()));
 }
 
-struct explicitly_convertible_to_wstring_view {
-  explicit operator fmt::wstring_view() const { return L"foo"; }
+#  ifdef FMT_USE_STRING_VIEW
+struct explicitly_convertible_to_std_string_view {
+  explicit operator std::string_view() const { return "foo"; }
 };
 
-TEST(FormatterTest, FormatExplicitlyConvertibleToWStringView) {
-  EXPECT_EQ(L"foo",
-            fmt::format(L"{}", explicitly_convertible_to_wstring_view()));
-}
-
-struct explicitly_convertible_to_string_like {
-  template <
-      typename String,
-      typename = typename std::enable_if<
-        std::is_constructible<String, const char*, std::size_t>::value>::type>
-  FMT_EXPLICIT operator String() const { return String("foo", 3u); }
-};
-
-TEST(FormatterTest, FormatExplicitlyConvertibleToStringLike) {
-  EXPECT_EQ("foo", fmt::format("{}", explicitly_convertible_to_string_like()));
+TEST(CoreTest, FormatExplicitlyConvertibleToStdStringView) {
+  EXPECT_EQ("foo",
+            fmt::format("{}", explicitly_convertible_to_std_string_view()));
 }
+#  endif
 #endif
+
+struct disabled_rvalue_conversion {
+  operator const char*() const& { return "foo"; }
+  operator const char*() & { return "foo"; }
+  operator const char*() const&& = delete;
+  operator const char*() && = delete;
+};
+
+TEST(CoreTest, DisabledRValueConversion) {
+  EXPECT_EQ("foo", fmt::format("{}", disabled_rvalue_conversion()));
+}

test/cuda-test/CMakeLists.txt

@@ -0,0 +1,73 @@
+# We can find some usecases which follow the guide of CMake which uses
+# `enable_language(CUDA)` instead of `find_package(CUDA)` and let the CMake
+# built-in functions use NVCC.
+
+# See: https://cmake.org/cmake/help/latest/module/FindCUDA.html#replacement
+#
+# However, this requires CMake version 3.10 or higher and we can't be sure most
+# of the CUDA projects are using those.
+#
+# This test relies on `find_package(CUDA)` in the parent CMake config.
+
+# These can be updated when NVCC becomes ready for C++ 17 features
+# https://docs.nvidia.com/cuda/cuda-c-programming-guide/index.html#cpp14-language-features
+set(CMAKE_CUDA_STANDARD 14)
+set(CMAKE_CUDA_STANDARD_REQUIRED 14)
+
+# In this test, we assume that the user is going to compile CUDA source code
+# with some libraries (fmt in this case).
+#
+# In addition to that, this test invokes both the C++ host compiler and NVCC
+# by providing another (non-CUDA) C++ source code.
+if (${CMAKE_VERSION} VERSION_LESS 3.15)
+  # https://docs.nvidia.com/cuda/cuda-compiler-driver-nvcc/index.html
+  list(APPEND CUDA_NVCC_FLAGS "-std=c++14")
+  if (MSVC)
+    # This is the solution of pytorch:
+    # https://github.com/pytorch/pytorch/pull/7118
+    list(APPEND CUDA_NVCC_FLAGS "-Xcompiler" "/std:c++14")
+    list(APPEND CUDA_NVCC_FLAGS "-Xcompiler" "/Zc:__cplusplus")
+    # for the reason of this -Xcompiler options, see below.
+  endif ()
+  cuda_add_executable(fmt-in-cuda-test cuda-cpp14.cu cpp14.cc)
+  target_compile_features(fmt-in-cuda-test PRIVATE cxx_std_14)
+  if (MSVC)
+    # This part is for (non-CUDA) C++ code. MSVC can define incorrect
+    # `__cplusplus` macro. Fix for the issue is to use additional compiler flag. 
+    #
+    # See Also:
+    # https://devblogs.microsoft.com/cppblog/msvc-now-correctly-reports-__cplusplus/
+    # https://github.com/Microsoft/vscode-cpptools/issues/2595
+    target_compile_options(fmt-in-cuda-test PRIVATE /Zc:__cplusplus /permissive-)
+  endif ()
+else()
+  # now using a "new" way of handling CUDA
+  add_executable(fmt-in-cuda-test cuda-cpp14.cu cpp14.cc)
+  set_target_properties(fmt-in-cuda-test PROPERTIES CUDA_SEPARABLE_COMPILATION ON)
+  target_compile_features(fmt-in-cuda-test PRIVATE cxx_std_14)
+  if (MSVC)
+    # with MSVC, 'cxx_std_14' will only propagate to the host code (MSVC), but will
+    # not set __cplusplus correctly anyway, while nvcc will ignore it.
+    # If specified for nvcc on the command line as '-std=c++14' nvcc will emit this
+    # message instead:
+    # nvcc warning : The -std=c++14 flag is not supported with the configured host
+    #                compiler. Flag will be ignored.
+    set_property(SOURCE cuda-cpp14.cu APPEND PROPERTY
+      COMPILE_OPTIONS -Xcompiler /std:c++14 -Xcompiler /Zc:__cplusplus)
+    set_property(SOURCE cpp14.cc APPEND PROPERTY
+      COMPILE_OPTIONS /std:c++14 /Zc:__cplusplus)
+  endif()
+endif()
+
+get_target_property(IN_USE_CUDA_STANDARD fmt-in-cuda-test CUDA_STANDARD)
+message(STATUS "cuda_standard:          ${IN_USE_CUDA_STANDARD}")
+
+get_target_property(IN_USE_CUDA_STANDARD_REQUIRED
+    fmt-in-cuda-test CUDA_STANDARD_REQUIRED)
+message(STATUS "cuda_standard_required: ${IN_USE_CUDA_STANDARD_REQUIRED}")
+
+# We don't use PUBLIC or other keyword for reasons explained in the
+# CUDA_LINK_LIBRARIES_KEYWORD section in
+# https://cmake.org/cmake/help/latest/module/FindCUDA.html
+target_link_libraries(fmt-in-cuda-test fmt::fmt)
+

test/cuda-test/cpp14.cc

@@ -0,0 +1,11 @@
+#include <fmt/core.h>
+
+// The purpose of this part is to ensure NVCC's host compiler also supports
+// the standard version. See 'cuda-cpp14.cu'.
+//
+// https://en.cppreference.com/w/cpp/preprocessor/replace#Predefined_macros
+static_assert(__cplusplus >= 201402L, "expect C++ 2014 for host compiler");
+
+auto make_message_cpp() -> std::string {
+  return fmt::format("host compiler \t: __cplusplus == {}", __cplusplus);
+}

test/cuda-test/cuda-cpp14.cu

@@ -0,0 +1,28 @@
+//  Direct NVCC command line example:
+//
+//  nvcc ./cuda-cpp14.cu -x cu -I"../include" -l"fmtd" -L"../build/Debug" \
+//       -std=c++14 -Xcompiler /std:c++14 -Xcompiler /Zc:__cplusplus
+
+// Ensure that we are using the latest C++ standard for NVCC
+// The version is C++14
+//
+// https://docs.nvidia.com/cuda/cuda-c-programming-guide/index.html#c-cplusplus-language-support
+// https://en.cppreference.com/w/cpp/preprocessor/replace#Predefined_macros
+static_assert(__cplusplus >= 201402L, "expect C++ 2014 for nvcc");
+
+#include <fmt/core.h>
+
+#include <cuda.h>
+#include <iostream>
+
+extern auto make_message_cpp() -> std::string;
+extern auto make_message_cuda() -> std::string;
+
+int main() {
+  std::cout << make_message_cuda() << std::endl;
+  std::cout << make_message_cpp() << std::endl;
+}
+
+auto make_message_cuda() -> std::string {
+  return fmt::format("nvcc compiler \t: __cplusplus == {}", __cplusplus);
+}

test/custom-formatter-test.cc

@@ -1,52 +0,0 @@
-// Formatting library for C++ - custom argument formatter tests
-//
-// Copyright (c) 2012 - present, Victor Zverovich
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-#include "fmt/format.h"
-#include "gtest-extra.h"
-
-// MSVC 2013 is known to be broken.
-#if !FMT_MSC_VER || FMT_MSC_VER > 1800
-
-// A custom argument formatter that doesn't print `-` for floating-point values
-// rounded to 0.
-class custom_arg_formatter :
-    public fmt::arg_formatter<fmt::back_insert_range<fmt::internal::buffer>> {
- public:
-  typedef fmt::back_insert_range<fmt::internal::buffer> range;
-  typedef fmt::arg_formatter<range> base;
-
-  custom_arg_formatter(
-      fmt::format_context &ctx, fmt::format_specs *s = FMT_NULL)
-  : base(ctx, s) {}
-
-  using base::operator();
-
-  iterator operator()(double value) {
-    // Comparing a float to 0.0 is safe.
-    if (round(value * pow(10, spec()->precision)) == 0.0)
-      value = 0;
-    return base::operator()(value);
-  }
-};
-
-std::string custom_vformat(fmt::string_view format_str, fmt::format_args args) {
-  fmt::memory_buffer buffer;
-  // Pass custom argument formatter as a template arg to vwrite.
-  fmt::vformat_to<custom_arg_formatter>(buffer, format_str, args);
-  return std::string(buffer.data(), buffer.size());
-}
-
-template <typename... Args>
-std::string custom_format(const char *format_str, const Args & ... args) {
-  auto va = fmt::make_format_args(args...);
-  return custom_vformat(format_str, va);
-}
-
-TEST(CustomFormatterTest, Format) {
-  EXPECT_EQ("0.00", custom_format("{:.2f}", -.00001));
-}
-#endif

test/find-package-test/CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.1.0)
+cmake_minimum_required(VERSION 3.1...3.18)
 
 project(fmt-test)
 

test/format

@@ -0,0 +1,855 @@
+// Formatting library for C++ - the standard API implementation
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_FORMAT_
+#define FMT_FORMAT_
+
+#include <cassert>
+#include <variant>
+#include "fmt/format.h"
+
+// This implementation verifies the correctness of the standard API proposed in
+// P0645 Text Formatting and is optimized for copy-pasting from the paper, not
+// for efficiency or readability. An efficient implementation should not use
+// std::variant and should store packed argument type tags separately from
+// values in basic_format_args for small number of arguments.
+
+namespace std {
+template<class T>
+constexpr bool Integral = is_integral_v<T>;
+
+template <class O>
+  using iter_difference_t = ptrdiff_t;
+}
+
+// https://fmt.dev/Text%20Formatting.html#format.syn
+namespace std {
+  // [format.error], class format_error
+  class format_error;
+
+  // [format.formatter], formatter
+  template<class charT> class basic_format_parse_context;
+  using format_parse_context = basic_format_parse_context<char>;
+  using wformat_parse_context = basic_format_parse_context<wchar_t>;
+  
+  template<class Out, class charT> class basic_format_context;
+  using format_context = basic_format_context<
+    /* unspecified */ fmt::detail::buffer_appender<char>, char>;
+  using wformat_context = basic_format_context<
+    /* unspecified */ fmt::detail::buffer_appender<wchar_t>, wchar_t>;
+
+  template<class T, class charT = char> struct formatter {
+    formatter() = delete;
+  };
+  
+  // [format.arguments], arguments
+  template<class Context> class basic_format_arg;
+
+  template<class Visitor, class Context>
+    /* see below */ auto visit_format_arg(Visitor&& vis, basic_format_arg<Context> arg);
+
+  template<class Context, class... Args> struct format_arg_store; // exposition only
+
+  template<class Context> class basic_format_args;
+  using format_args = basic_format_args<format_context>;
+  using wformat_args = basic_format_args<wformat_context>;
+
+  template<class Out, class charT>
+    using format_args_t = basic_format_args<basic_format_context<Out, charT>>;
+
+  template<class Context = format_context, class... Args>
+    format_arg_store<Context, Args...>
+      make_format_args(const Args&... args);
+  template<class... Args>
+    format_arg_store<wformat_context, Args...>
+      make_wformat_args(const Args&... args);
+
+  // [format.functions], formatting functions
+  template<class... Args>
+    string format(string_view fmt, const Args&... args);
+  template<class... Args>
+    wstring format(wstring_view fmt, const Args&... args);
+
+  string vformat(string_view fmt, format_args args);
+  wstring vformat(wstring_view fmt, wformat_args args);
+
+  template<class Out, class... Args>
+    Out format_to(Out out, string_view fmt, const Args&... args);
+  template<class Out, class... Args>
+    Out format_to(Out out, wstring_view fmt, const Args&... args);
+
+  template<class Out>
+    Out vformat_to(Out out, string_view fmt, format_args_t<fmt::type_identity_t<Out>, char> args);
+  template<class Out>
+    Out vformat_to(Out out, wstring_view fmt, format_args_t<fmt::type_identity_t<Out>, wchar_t> args);
+
+  template<class Out>
+    struct format_to_n_result {
+      Out out;
+      iter_difference_t<Out> size;
+    };
+  
+  template<class Out, class... Args>
+    format_to_n_result<Out> format_to_n(Out out, iter_difference_t<Out> n,
+                                        string_view fmt, const Args&... args);
+  template<class Out, class... Args>
+    format_to_n_result<Out> format_to_n(Out out, iter_difference_t<Out> n,
+                                        wstring_view fmt, const Args&... args);
+
+  template<class... Args>
+    size_t formatted_size(string_view fmt, const Args&... args);
+  template<class... Args>
+    size_t formatted_size(wstring_view fmt, const Args&... args);
+}
+
+// https://fmt.dev/Text%20Formatting.html#format.error
+namespace std {
+  class format_error : public runtime_error {
+  public:
+    explicit format_error(const string& what_arg) : runtime_error(what_arg) {}
+    explicit format_error(const char* what_arg) : runtime_error(what_arg) {}
+  };
+}
+
+namespace std {
+namespace detail {
+struct error_handler {
+  // This function is intentionally not constexpr to give a compile-time error.
+  void on_error(const char* message) {
+    throw std::format_error(message);
+  }
+};
+}
+}
+
+// https://fmt.dev/Text%20Formatting.html#format.parse_context
+namespace std {
+  template<class charT>
+  class basic_format_parse_context {
+  public:
+    using char_type = charT;
+    using const_iterator = typename basic_string_view<charT>::const_iterator;
+    using iterator = const_iterator;
+
+  private:
+    iterator begin_;                              // exposition only
+    iterator end_;                                // exposition only
+    enum indexing { unknown, manual, automatic }; // exposition only
+    indexing indexing_;                           // exposition only
+    size_t next_arg_id_;                          // exposition only
+    size_t num_args_;                             // exposition only
+
+  public:
+    explicit constexpr basic_format_parse_context(basic_string_view<charT> fmt,
+                                                  size_t num_args = 0) noexcept;
+    basic_format_parse_context(const basic_format_parse_context&) = delete;
+    basic_format_parse_context& operator=(const basic_format_parse_context&) = delete;
+
+    constexpr const_iterator begin() const noexcept;
+    constexpr const_iterator end() const noexcept;
+    constexpr void advance_to(const_iterator it);
+
+    constexpr size_t next_arg_id();
+    constexpr void check_arg_id(size_t id);
+
+    // Implementation detail:
+    constexpr void check_arg_id(fmt::string_view) {}
+    detail::error_handler error_handler() const { return {}; }
+    void on_error(const char* msg) { error_handler().on_error(msg); }
+  };
+}
+
+namespace std {
+template<class charT>
+/* explicit */ constexpr basic_format_parse_context<charT>::
+                   basic_format_parse_context(basic_string_view<charT> fmt,
+                                              size_t num_args) noexcept
+: begin_(fmt.begin()), end_(fmt.end()), indexing_(unknown), next_arg_id_(0), num_args_(num_args) {}
+
+template<class charT>
+constexpr typename basic_format_parse_context<charT>::const_iterator basic_format_parse_context<charT>::begin() const noexcept { return begin_; }
+
+template<class charT>
+constexpr typename basic_format_parse_context<charT>::const_iterator basic_format_parse_context<charT>::end() const noexcept { return end_; }
+
+template<class charT>
+constexpr void basic_format_parse_context<charT>::advance_to(typename basic_format_parse_context<charT>::iterator it) { begin_ = it; }
+
+template<class charT>
+constexpr size_t basic_format_parse_context<charT>::next_arg_id() {
+  if (indexing_ == manual)
+    throw format_error("manual to automatic indexing");
+  if (indexing_ == unknown)
+    indexing_ = automatic;
+  return next_arg_id_++;
+}
+
+template<class charT>
+constexpr void basic_format_parse_context<charT>::check_arg_id(size_t id) {
+  // clang doesn't support __builtin_is_constant_evaluated yet
+  //if (!(!__builtin_is_constant_evaluated() || id < num_args_))
+  //  throw format_error(invalid index is out of range");
+  if (indexing_ == automatic)
+    throw format_error("automatic to manual indexing");
+  if (indexing_ == unknown)
+    indexing_ = manual;
+}
+}
+
+// https://fmt.dev/Text%20Formatting.html#format.context
+namespace std {
+  template<class Out, class charT>
+  class basic_format_context {
+    basic_format_args<basic_format_context> args_; // exposition only
+    Out out_;                                      // exposition only
+
+  public:
+    using iterator = Out;
+    using char_type = charT;
+    template<class T> using formatter_type = formatter<T, charT>;
+
+    basic_format_arg<basic_format_context> arg(size_t id) const;
+
+    iterator out();
+    void advance_to(iterator it);
+
+    // Implementation details:
+    using format_arg = basic_format_arg<basic_format_context>;
+    basic_format_context(Out out, basic_format_args<basic_format_context> args, fmt::detail::locale_ref)
+    : args_(args), out_(out) {}
+    detail::error_handler error_handler() const { return {}; }
+    basic_format_arg<basic_format_context> arg(fmt::basic_string_view<charT>) const {
+      return {}; // unused: named arguments are not supported yet
+    }
+    void on_error(const char* msg) { error_handler().on_error(msg); }
+  };
+}
+
+namespace std {
+template<class O, class charT>
+basic_format_arg<basic_format_context<O, charT>> basic_format_context<O, charT>::arg(size_t id) const { return args_.get(id); }
+
+template<class O, class charT>
+typename basic_format_context<O, charT>::iterator basic_format_context<O, charT>::out() { return out_; }
+
+template<class O, class charT>
+void basic_format_context<O, charT>::advance_to(typename basic_format_context<O, charT>::iterator it) { out_ = it; }
+}
+
+namespace std {
+namespace detail {
+template <typename T>
+constexpr bool is_standard_integer_v =
+    std::is_same_v<T, signed char> ||
+    std::is_same_v<T, short int> ||
+    std::is_same_v<T, int> ||
+    std::is_same_v<T, long int> ||
+    std::is_same_v<T, long long int>;
+
+template <typename T>
+constexpr bool is_standard_unsigned_integer_v =
+    std::is_same_v<T, unsigned char> ||
+    std::is_same_v<T, unsigned short int> ||
+    std::is_same_v<T, unsigned int> ||
+    std::is_same_v<T, unsigned long int> ||
+    std::is_same_v<T, unsigned long long int>;
+
+template <typename T, typename Char> struct formatter;
+}
+}
+
+// https://fmt.dev/Text%20Formatting.html#format.arg
+namespace std {
+  template<class Context>
+  class basic_format_arg {
+  public:
+    class handle;
+
+  private:
+    using char_type = typename Context::char_type;                       // exposition only
+
+    variant<monostate, bool, char_type,
+            int, unsigned int, long long int, unsigned long long int,
+            double, long double,
+            const char_type*, basic_string_view<char_type>,
+            const void*, handle> value;                                  // exposition only
+
+    template<typename T,
+      typename = enable_if_t<
+        std::is_same_v<T, bool> ||
+        std::is_same_v<T, char_type> ||
+        (std::is_same_v<T, char> && std::is_same_v<char_type, wchar_t>) ||
+        detail::is_standard_integer_v<T> ||
+        detail::is_standard_unsigned_integer_v<T> ||
+        sizeof(typename Context::template formatter_type<T>().format(declval<const T&>(), declval<Context&>())) != 0
+    >> explicit basic_format_arg(const T& v) noexcept; // exposition only
+    explicit basic_format_arg(float n) noexcept;                         // exposition only
+    explicit basic_format_arg(double n) noexcept;                        // exposition only
+    explicit basic_format_arg(long double n) noexcept;                   // exposition only
+    explicit basic_format_arg(const char_type* s);                       // exposition only
+
+    template<class traits>
+      explicit basic_format_arg(
+        basic_string_view<char_type, traits> s) noexcept;                // exposition only
+
+    template<class traits, class Allocator>
+      explicit basic_format_arg(
+        const basic_string<char_type, traits, Allocator>& s) noexcept;   // exposition only
+
+    explicit basic_format_arg(nullptr_t) noexcept;                       // exposition only
+
+    template<class T, typename = enable_if_t<is_void_v<T>>>
+      explicit basic_format_arg(const T* p) noexcept;                    // exposition only
+
+    // Fails due to a bug in clang
+    //template<class Visitor, class Ctx>
+    //  friend auto visit_format_arg(Visitor&& vis,
+    //                                    basic_format_arg<Ctx> arg);           // exposition only
+
+    friend auto get_value(basic_format_arg arg) {
+      return arg.value;
+    }
+
+    template <typename T, typename Char> friend struct detail::formatter;
+
+    template<class Ctx, class... Args>
+      friend format_arg_store<Ctx, Args...>
+        make_format_args(const Args&... args);                           // exposition only
+
+  public:
+    basic_format_arg() noexcept;
+
+    explicit operator bool() const noexcept;
+  };
+}
+
+namespace std {
+template<class Context>
+basic_format_arg<Context>::basic_format_arg() noexcept {}
+
+template<class Context>
+template<class T, typename> /* explicit */ basic_format_arg<Context>::basic_format_arg(const T& v) noexcept {
+  if constexpr (std::is_same_v<T, bool> || std::is_same_v<T, char_type>)
+    value = v;
+  else if constexpr (std::is_same_v<T, char> && std::is_same_v<char_type, wchar_t>)
+    value = static_cast<wchar_t>(v);
+  else if constexpr (detail::is_standard_integer_v<T> && sizeof(T) <= sizeof(int))
+    value = static_cast<int>(v);
+  else if constexpr (detail::is_standard_unsigned_integer_v<T> && sizeof(T) <= sizeof(unsigned))
+    value = static_cast<unsigned>(v);
+  else if constexpr (detail::is_standard_integer_v<T>)
+    value = static_cast<long long int>(v);
+  else if constexpr (detail::is_standard_unsigned_integer_v<T>)
+    value = static_cast<unsigned long long int>(v);
+  else if constexpr (sizeof(typename Context::template formatter_type<T>().format(declval<const T&>(), declval<Context&>())) != 0)
+    value = handle(v);
+}
+
+template<class Context>
+/* explicit */ basic_format_arg<Context>::basic_format_arg(float n) noexcept
+  : value(static_cast<double>(n)) {}
+
+template<class Context>
+/* explicit */ basic_format_arg<Context>::basic_format_arg(double n) noexcept
+  : value(n) {}
+
+template<class Context>
+/* explicit */ basic_format_arg<Context>::basic_format_arg(long double n) noexcept
+  : value(n) {}
+
+template<class Context>
+/* explicit */ basic_format_arg<Context>::basic_format_arg(const typename basic_format_arg<Context>::char_type* s)
+  : value(s) {
+  assert(s != nullptr);
+}
+
+template<class Context>
+template<class traits>
+/* explicit */ basic_format_arg<Context>::basic_format_arg(basic_string_view<char_type, traits> s) noexcept
+  : value(s) {}
+
+template<class Context>
+template<class traits, class Allocator>
+/* explicit */ basic_format_arg<Context>::basic_format_arg(
+    const basic_string<char_type, traits, Allocator>& s) noexcept
+  : value(basic_string_view<char_type>(s.data(), s.size())) {}
+
+
+template<class Context>
+/* explicit */ basic_format_arg<Context>::basic_format_arg(nullptr_t) noexcept
+  : value(static_cast<const void*>(nullptr)) {}
+
+template<class Context>
+template<class T, typename> /* explicit */ basic_format_arg<Context>::basic_format_arg(const T* p) noexcept
+  : value(p) {}
+
+template<class Context>
+/* explicit */ basic_format_arg<Context>::operator bool() const noexcept {
+    return !holds_alternative<monostate>(value);
+}
+}
+
+namespace std {
+  template<class Context>
+  class basic_format_arg<Context>::handle {
+    const void* ptr_;                                         // exposition only
+    void (*format_)(basic_format_parse_context<char_type>&,
+                    Context&, const void*);                   // exposition only
+
+    template<class T> explicit handle(const T& val) noexcept; // exposition only
+
+    friend class basic_format_arg<Context>;                   // exposition only
+
+  public:
+    void format(basic_format_parse_context<char_type>&, Context& ctx) const;
+  };
+}
+
+namespace std {
+template<class Context>
+template<class T> /* explicit */ basic_format_arg<Context>::handle::handle(const T& val) noexcept
+  : ptr_(&val), format_([](basic_format_parse_context<char_type>& parse_ctx, Context& format_ctx, const void* ptr) {
+    typename Context::template formatter_type<T> f;
+    parse_ctx.advance_to(f.parse(parse_ctx));
+    format_ctx.advance_to(f.format(*static_cast<const T*>(ptr), format_ctx));
+  }) {}
+
+template<class Context>
+void basic_format_arg<Context>::handle::format(basic_format_parse_context<char_type>& parse_ctx, Context& format_ctx) const {
+  format_(parse_ctx, format_ctx, ptr_);
+}
+
+// https://fmt.dev/Text%20Formatting.html#format.visit
+template<class Visitor, class Context>
+  auto visit_format_arg(Visitor&& vis, basic_format_arg<Context> arg) {
+    return visit(vis, get_value(arg));
+  }
+}
+
+// https://fmt.dev/Text%20Formatting.html#format.store
+namespace std {
+  template<class Context, class... Args>
+  struct format_arg_store { // exposition only
+    array<basic_format_arg<Context>, sizeof...(Args)> args;
+  };
+}
+
+// https://fmt.dev/Text%20Formatting.html#format.basic_args
+namespace std {
+  template<class Context>
+  class basic_format_args {
+    size_t size_;                           // exposition only
+    const basic_format_arg<Context>* data_; // exposition only
+
+  public:
+    basic_format_args() noexcept;
+
+    template<class... Args>
+      basic_format_args(const format_arg_store<Context, Args...>& store) noexcept;
+
+    basic_format_arg<Context> get(size_t i) const noexcept;
+  };
+}
+
+namespace std {
+
+template<class Context>
+basic_format_args<Context>::basic_format_args() noexcept : size_(0) {}
+
+template<class Context>
+template<class... Args>
+  basic_format_args<Context>::basic_format_args(const format_arg_store<Context, Args...>& store) noexcept
+  : size_(sizeof...(Args)), data_(store.args.data()) {}
+
+template<class Context>
+basic_format_arg<Context> basic_format_args<Context>::get(size_t i) const noexcept {
+  return i < size_ ? data_[i] : basic_format_arg<Context>();
+}
+}
+
+namespace std {
+// https://fmt.dev/Text%20Formatting.html#format.make_args
+template<class Context /*= format_context*/, class... Args>
+  format_arg_store<Context, Args...> make_format_args(const Args&... args) {
+    return {basic_format_arg<Context>(args)...};
+  }
+
+// https://fmt.dev/Text%20Formatting.html#format.make_wargs
+template<class... Args>
+  format_arg_store<wformat_context, Args...> make_wformat_args(const Args&... args) {
+    return make_format_args<wformat_context>(args...);
+  }
+}
+
+namespace std {
+namespace detail {
+
+template <typename OutputIt, typename Char>
+class arg_formatter
+    : public fmt::detail::arg_formatter_base<OutputIt, Char, error_handler> {
+ private:
+  using char_type = Char;
+  using base = fmt::detail::arg_formatter_base<OutputIt, Char, error_handler>;
+  using format_context = std::basic_format_context<OutputIt, Char>;
+  using parse_context = basic_format_parse_context<Char>;
+
+  parse_context* parse_ctx_;
+  format_context& ctx_;
+
+ public:
+  using iterator = OutputIt;
+  using format_specs = typename base::format_specs;
+
+  /**
+    \rst
+    Constructs an argument formatter object.
+    *ctx* is a reference to the formatting context,
+    *spec* contains format specifier information for standard argument types.
+    \endrst
+   */
+  arg_formatter(format_context& ctx, parse_context* parse_ctx = nullptr, fmt::format_specs* spec = nullptr)
+      : base(ctx.out(), spec, {}), parse_ctx_(parse_ctx), ctx_(ctx) {}
+
+  using base::operator();
+
+  /** Formats an argument of a user-defined type. */
+  iterator operator()(typename std::basic_format_arg<format_context>::handle handle) {
+    handle.format(*parse_ctx_, ctx_);
+    return this->out();
+  }
+
+  iterator operator()(monostate) {
+    throw format_error("");
+  }
+};
+
+template <typename Context>
+inline fmt::detail::type get_type(basic_format_arg<Context> arg) {
+  return visit_format_arg([&] (auto val) {
+    using char_type = typename Context::char_type;
+    using T = decltype(val);
+    if (std::is_same_v<T, monostate>)
+      return fmt::detail::type::none_type;
+    if (std::is_same_v<T, bool>)
+      return fmt::detail::type::bool_type;
+    if (std::is_same_v<T, char_type>)
+      return fmt::detail::type::char_type;
+    if (std::is_same_v<T, int>)
+      return fmt::detail::type::int_type;
+    if (std::is_same_v<T, unsigned int>)
+      return fmt::detail::type::uint_type;
+    if (std::is_same_v<T, long long int>)
+      return fmt::detail::type::long_long_type;
+    if (std::is_same_v<T, unsigned long long int>)
+      return fmt::detail::type::ulong_long_type;
+    if (std::is_same_v<T, double>)
+      return fmt::detail::type::double_type;
+    if (std::is_same_v<T, long double>)
+      return fmt::detail::type::long_double_type;
+    if (std::is_same_v<T, const char_type*>)
+      return fmt::detail::type::cstring_type;
+    if (std::is_same_v<T, basic_string_view<char_type>>)
+      return fmt::detail::type::string_type;
+    if (std::is_same_v<T, const void*>)
+      return fmt::detail::type::pointer_type;
+    assert(get_value(arg).index() == 12);
+    return fmt::detail::type::custom_type;
+  }, arg);
+}
+
+template <typename Context>
+class custom_formatter {
+ private:
+  using parse_context = basic_format_parse_context<typename Context::char_type>;
+  parse_context& parse_ctx_;
+  Context& format_ctx_;
+
+ public:
+  custom_formatter(parse_context& parse_ctx, Context& ctx) : parse_ctx_(parse_ctx), format_ctx_(ctx) {}
+
+  bool operator()(typename basic_format_arg<Context>::handle h) const {
+    h.format(parse_ctx_, format_ctx_);
+    return true;
+  }
+
+  template <typename T> bool operator()(T) const { return false; }
+};
+
+template <typename ArgFormatter, typename Char, typename Context>
+struct format_handler : detail::error_handler {
+  using iterator = typename ArgFormatter::iterator;
+
+  format_handler(iterator out, basic_string_view<Char> str,
+                 basic_format_args<Context> format_args,
+                 fmt::detail::locale_ref loc)
+      : parse_ctx(str), context(out, format_args, loc) {}
+
+  void on_text(const Char* begin, const Char* end) {
+    auto size = fmt::detail::to_unsigned(end - begin);
+    auto out = context.out();
+    auto&& it = fmt::detail::reserve(out, size);
+    it = std::copy_n(begin, size, it);
+    context.advance_to(out);
+  }
+
+  int on_arg_id() { return parse_ctx.next_arg_id(); }
+  int on_arg_id(unsigned id) { return parse_ctx.check_arg_id(id), id; }
+  int on_arg_id(fmt::basic_string_view<Char>) { return 0; }
+
+  void on_replacement_field(int id, const Char* p) {
+    auto arg = context.arg(id);
+    parse_ctx.advance_to(parse_ctx.begin() + (p  - &*parse_ctx.begin()));
+    custom_formatter<Context> f(parse_ctx, context);
+    if (!visit_format_arg(f, arg))
+      context.advance_to(visit_format_arg(ArgFormatter(context, &parse_ctx), arg));
+  }
+
+  const Char* on_format_specs(int id, const Char* begin, const Char* end) {
+    auto arg = context.arg(id);
+    parse_ctx.advance_to(parse_ctx.begin() + (begin - &*parse_ctx.begin()));
+    custom_formatter<Context> f(parse_ctx, context);
+    if (visit_format_arg(f, arg)) return &*parse_ctx.begin();
+    fmt::basic_format_specs<Char> specs;
+    using fmt::detail::specs_handler;
+    using parse_context = basic_format_parse_context<Char>;
+    fmt::detail::specs_checker<specs_handler<parse_context, Context>> handler(
+        specs_handler<parse_context, Context>(specs, parse_ctx, context), get_type(arg));
+    begin = parse_format_specs(begin, end, handler);
+    if (begin == end || *begin != '}') on_error("missing '}' in format string");
+    parse_ctx.advance_to(parse_ctx.begin() + (begin - &*parse_ctx.begin()));
+    context.advance_to(visit_format_arg(ArgFormatter(context, &parse_ctx, &specs), arg));
+    return begin;
+  }
+
+  basic_format_parse_context<Char> parse_ctx;
+  Context context;
+};
+
+template <typename T, typename Char>
+struct formatter {
+  // Parses format specifiers stopping either at the end of the range or at the
+  // terminating '}'.
+  template <typename ParseContext>
+  FMT_CONSTEXPR typename ParseContext::iterator parse(ParseContext& ctx) {
+    namespace detail = fmt::detail;
+    typedef detail::dynamic_specs_handler<ParseContext> handler_type;
+    auto type = detail::mapped_type_constant<T, fmt::buffer_context<Char>>::value;
+    detail::specs_checker<handler_type> handler(handler_type(specs_, ctx),
+                                                  type);
+    auto it = parse_format_specs(ctx.begin(), ctx.end(), handler);
+    auto type_spec = specs_.type;
+    auto eh = ctx.error_handler();
+    switch (type) {
+    case detail::type::none_type:
+      FMT_ASSERT(false, "invalid argument type");
+      break;
+    case detail::type::int_type:
+    case detail::type::uint_type:
+    case detail::type::long_long_type:
+    case detail::type::ulong_long_type:
+    case detail::type::bool_type:
+      handle_int_type_spec(type_spec,
+                           detail::int_type_checker<decltype(eh)>(eh));
+      break;
+    case detail::type::char_type:
+      handle_char_specs(
+          &specs_, detail::char_specs_checker<decltype(eh)>(type_spec, eh));
+      break;
+    case detail::type::double_type:
+    case detail::type::long_double_type:
+      detail::parse_float_type_spec(specs_, eh);
+      break;
+    case detail::type::cstring_type:
+      detail::handle_cstring_type_spec(
+          type_spec, detail::cstring_type_checker<decltype(eh)>(eh));
+      break;
+    case detail::type::string_type:
+      detail::check_string_type_spec(type_spec, eh);
+      break;
+    case detail::type::pointer_type:
+      detail::check_pointer_type_spec(type_spec, eh);
+      break;
+    case detail::type::custom_type:
+      // Custom format specifiers should be checked in parse functions of
+      // formatter specializations.
+      break;
+    }
+    return it;
+  }
+
+  template <typename FormatContext>
+  auto format(const T& val, FormatContext& ctx) -> decltype(ctx.out()) {
+    fmt::detail::handle_dynamic_spec<fmt::detail::width_checker>(
+        specs_.width, specs_.width_ref, ctx);
+    fmt::detail::handle_dynamic_spec<fmt::detail::precision_checker>(
+        specs_.precision, specs_.precision_ref, ctx);
+    using af = arg_formatter<typename FormatContext::iterator,
+                             typename FormatContext::char_type>;
+    return visit_format_arg(af(ctx, nullptr, &specs_),
+                            basic_format_arg<FormatContext>(val));
+  }
+
+ private:
+  fmt::detail::dynamic_format_specs<Char> specs_;
+};
+}  // namespace detail
+
+// https://fmt.dev/Text%20Formatting.html#format.functions
+template<class... Args>
+  string format(string_view fmt, const Args&... args) {
+    return vformat(fmt, make_format_args(args...));
+  }
+
+template<class... Args>
+  wstring format(wstring_view fmt, const Args&... args) {
+    return vformat(fmt, make_wformat_args(args...));
+  }
+
+string vformat(string_view fmt, format_args args) {
+  fmt::memory_buffer mbuf;
+  fmt::detail::buffer<char>& buf = mbuf;
+  using af = detail::arg_formatter<fmt::format_context::iterator, char>;
+  detail::format_handler<af, char, format_context>
+    h(fmt::detail::buffer_appender<char>(buf), fmt, args, {});
+  fmt::detail::parse_format_string<false>(fmt::to_string_view(fmt), h);
+  return to_string(mbuf);
+}
+
+wstring vformat(wstring_view fmt, wformat_args args);
+
+template<class Out, class... Args>
+  Out format_to(Out out, string_view fmt, const Args&... args) {
+    using context = basic_format_context<Out, decltype(fmt)::value_type>;
+    return vformat_to(out, fmt, make_format_args<context>(args...));
+  }
+
+template<class Out, class... Args>
+  Out format_to(Out out, wstring_view fmt, const Args&... args) {
+    using context = basic_format_context<Out, decltype(fmt)::value_type>;
+    return vformat_to(out, fmt, make_format_args<context>(args...));
+  }
+
+template<class Out>
+  Out vformat_to(Out out, string_view fmt, format_args_t<fmt::type_identity_t<Out>, char> args) {
+    using af = detail::arg_formatter<Out, char>;
+    detail::format_handler<af, char, basic_format_context<Out, char>>
+      h(out, fmt, args, {});
+    fmt::detail::parse_format_string<false>(fmt::to_string_view(fmt), h);
+    return h.context.out();
+  }
+
+template<class Out>
+  Out vformat_to(Out out, wstring_view fmt, format_args_t<fmt::type_identity_t<Out>, wchar_t> args);
+
+template<class Out, class... Args>
+  format_to_n_result<Out> format_to_n(Out out, iter_difference_t<Out> n,
+                                      string_view fmt, const Args&... args);
+template<class Out, class... Args>
+  format_to_n_result<Out> format_to_n(Out out, iter_difference_t<Out> n,
+                                      wstring_view fmt, const Args&... args);
+
+template<class... Args>
+  size_t formatted_size(string_view fmt, const Args&... args);
+template<class... Args>
+  size_t formatted_size(wstring_view fmt, const Args&... args);
+
+#define charT char
+
+template<> struct formatter<charT, charT> : detail::formatter<charT, charT> {};
+
+template<> struct formatter<char, wchar_t>;
+
+template<> struct formatter<charT*, charT> : detail::formatter<const charT*, charT> {};
+
+template<> struct formatter<const charT*, charT> : detail::formatter<const charT*, charT> {};
+
+template<size_t N> struct formatter<const charT[N], charT>
+      : detail::formatter<std::basic_string_view<charT>, charT> {};
+
+template<class traits, class Allocator>
+  struct formatter<basic_string<charT, traits, Allocator>, charT>
+      : detail::formatter<std::basic_string_view<charT>, charT> {};
+
+template<class traits>
+  struct formatter<basic_string_view<charT, traits>, charT>
+      : detail::formatter<std::basic_string_view<charT>, charT> {};
+
+template <> struct formatter<nullptr_t, charT> : detail::formatter<const void*, charT> {};
+template <> struct formatter<void*, charT> : detail::formatter<const void*, charT> {};
+template <> struct formatter<const void*, charT> : detail::formatter<const void*, charT> {};
+template <> struct formatter<bool, charT> : detail::formatter<bool, charT> {};
+
+template <> struct formatter<signed char, charT> : detail::formatter<int, charT> {};
+template <> struct formatter<short, charT> : detail::formatter<int, charT> {};
+template <> struct formatter<int, charT> : detail::formatter<int, charT> {};
+template <> struct formatter<long, charT>
+      : detail::formatter<std::conditional_t<sizeof(long) == sizeof(int), int, long long>, charT> {};
+template <> struct formatter<long long, charT> : detail::formatter<long long, charT> {};
+template <> struct formatter<unsigned char, charT> : detail::formatter<unsigned int, charT> {};
+template <> struct formatter<unsigned short, charT> : detail::formatter<unsigned int, charT> {};
+template <> struct formatter<unsigned int, charT> : detail::formatter<unsigned int, charT> {};
+template <> struct formatter<unsigned long, charT>
+      : detail::formatter<std::conditional_t<sizeof(long) == sizeof(int), unsigned, unsigned long long>, charT> {};
+template <> struct formatter<unsigned long long, charT> : detail::formatter<unsigned long long, charT> {};
+
+template <> struct formatter<float, charT> : detail::formatter<double, charT> {};
+template <> struct formatter<double, charT> : detail::formatter<double, charT> {};
+template <> struct formatter<long double, charT> : detail::formatter<long double, charT> {};
+
+#undef charT
+
+#define charT wchar_t
+
+template<> struct formatter<charT, charT> : detail::formatter<charT, charT> {};
+
+template<> struct formatter<char, wchar_t> : detail::formatter<charT, charT> {};
+
+template<> struct formatter<charT*, charT> : detail::formatter<const charT*, charT> {};
+
+template<> struct formatter<const charT*, charT> : detail::formatter<const charT*, charT> {};
+
+template<size_t N> struct formatter<const charT[N], charT>
+      : detail::formatter<std::basic_string_view<charT>, charT> {};
+
+template<class traits, class Allocator>
+  struct formatter<std::basic_string<charT, traits, Allocator>, charT>
+      : detail::formatter<std::basic_string_view<charT>, charT> {};
+
+template<class traits>
+  struct formatter<std::basic_string_view<charT, traits>, charT>
+      : detail::formatter<std::basic_string_view<charT>, charT> {};
+
+template <> struct formatter<nullptr_t, charT> : detail::formatter<const void*, charT> {};
+template <> struct formatter<void*, charT> : detail::formatter<const void*, charT> {};
+template <> struct formatter<const void*, charT> : detail::formatter<const void*, charT> {};
+template <> struct formatter<bool, charT> : detail::formatter<bool, charT> {};
+
+template <> struct formatter<signed char, charT> : detail::formatter<int, charT> {};
+template <> struct formatter<short, charT> : detail::formatter<int, charT> {};
+template <> struct formatter<int, charT> : detail::formatter<int, charT> {};
+template <> struct formatter<long, charT>
+      : detail::formatter<std::conditional_t<sizeof(long) == sizeof(int), int, long long>, charT> {};
+template <> struct formatter<long long, charT> : detail::formatter<long long, charT> {};
+template <> struct formatter<unsigned char, charT> : detail::formatter<unsigned int, charT> {};
+template <> struct formatter<unsigned short, charT> : detail::formatter<unsigned int, charT> {};
+template <> struct formatter<unsigned int, charT> : detail::formatter<unsigned int, charT> {};
+template <> struct formatter<unsigned long, charT>
+      : detail::formatter<std::conditional_t<sizeof(long) == sizeof(int), unsigned, unsigned long long>, charT> {};
+template <> struct formatter<unsigned long long, charT> : detail::formatter<unsigned long long, charT> {};
+
+template <> struct formatter<float, charT> : detail::formatter<double, charT> {};
+template <> struct formatter<double, charT> : detail::formatter<double, charT> {};
+template <> struct formatter<long double, charT> : detail::formatter<long double, charT> {};
+
+#undef charT
+
+  template<> struct formatter<const wchar_t, char> {
+    formatter() = delete;
+  };
+}
+
+#endif  // FMT_FORMAT_

test/format-impl-test.cc

@@ -10,75 +10,196 @@
 #include "test-assert.h"
 
 // Include format.cc instead of format.h to test implementation.
-#include "../src/format.cc"
-#include "fmt/color.h"
-#include "fmt/printf.h"
-
 #include <algorithm>
 #include <cstring>
 
+#include "../src/format.cc"
+#include "fmt/printf.h"
 #include "gmock.h"
 #include "gtest-extra.h"
 #include "util.h"
 
-#undef min
-#undef max
-
-#if FMT_HAS_CPP_ATTRIBUTE(noreturn)
-# define FMT_NORETURN [[noreturn]]
-#else
-# define FMT_NORETURN
+#ifdef _WIN32
+#  include <windows.h>
+#  undef max
 #endif
 
-using fmt::internal::fp;
+using fmt::detail::bigint;
+using fmt::detail::fp;
+using fmt::detail::max_value;
 
-template <bool is_iec559>
-void test_construct_from_double() {
+static_assert(!std::is_copy_constructible<bigint>::value, "");
+static_assert(!std::is_copy_assignable<bigint>::value, "");
+
+TEST(BigIntTest, Construct) {
+  EXPECT_EQ("", fmt::format("{}", bigint()));
+  EXPECT_EQ("42", fmt::format("{}", bigint(0x42)));
+  EXPECT_EQ("123456789abcedf0", fmt::format("{}", bigint(0x123456789abcedf0)));
+}
+
+TEST(BigIntTest, Compare) {
+  bigint n1(42);
+  bigint n2(42);
+  EXPECT_EQ(compare(n1, n2), 0);
+  n2 <<= 32;
+  EXPECT_LT(compare(n1, n2), 0);
+  bigint n3(43);
+  EXPECT_LT(compare(n1, n3), 0);
+  EXPECT_GT(compare(n3, n1), 0);
+  bigint n4(42 * 0x100000001);
+  EXPECT_LT(compare(n2, n4), 0);
+  EXPECT_GT(compare(n4, n2), 0);
+}
+
+TEST(BigIntTest, AddCompare) {
+  EXPECT_LT(
+      add_compare(bigint(0xffffffff), bigint(0xffffffff), bigint(1) <<= 64), 0);
+  EXPECT_LT(add_compare(bigint(1) <<= 32, bigint(1), bigint(1) <<= 96), 0);
+  EXPECT_GT(add_compare(bigint(1) <<= 32, bigint(0), bigint(0xffffffff)), 0);
+  EXPECT_GT(add_compare(bigint(0), bigint(1) <<= 32, bigint(0xffffffff)), 0);
+  EXPECT_GT(add_compare(bigint(42), bigint(1), bigint(42)), 0);
+  EXPECT_GT(add_compare(bigint(0xffffffff), bigint(1), bigint(0xffffffff)), 0);
+  EXPECT_LT(add_compare(bigint(10), bigint(10), bigint(22)), 0);
+  EXPECT_LT(add_compare(bigint(0x100000010), bigint(0x100000010),
+                        bigint(0x300000010)),
+            0);
+  EXPECT_GT(add_compare(bigint(0x1ffffffff), bigint(0x100000002),
+                        bigint(0x300000000)),
+            0);
+  EXPECT_EQ(add_compare(bigint(0x1ffffffff), bigint(0x100000002),
+                        bigint(0x300000001)),
+            0);
+  EXPECT_LT(add_compare(bigint(0x1ffffffff), bigint(0x100000002),
+                        bigint(0x300000002)),
+            0);
+  EXPECT_LT(add_compare(bigint(0x1ffffffff), bigint(0x100000002),
+                        bigint(0x300000003)),
+            0);
+}
+
+TEST(BigIntTest, ShiftLeft) {
+  bigint n(0x42);
+  n <<= 0;
+  EXPECT_EQ("42", fmt::format("{}", n));
+  n <<= 1;
+  EXPECT_EQ("84", fmt::format("{}", n));
+  n <<= 25;
+  EXPECT_EQ("108000000", fmt::format("{}", n));
+}
+
+TEST(BigIntTest, Multiply) {
+  bigint n(0x42);
+  EXPECT_THROW(n *= 0, assertion_failure);
+  n *= 1;
+  EXPECT_EQ("42", fmt::format("{}", n));
+  n *= 2;
+  EXPECT_EQ("84", fmt::format("{}", n));
+  n *= 0x12345678;
+  EXPECT_EQ("962fc95e0", fmt::format("{}", n));
+  bigint bigmax(max_value<uint32_t>());
+  bigmax *= max_value<uint32_t>();
+  EXPECT_EQ("fffffffe00000001", fmt::format("{}", bigmax));
+  bigmax.assign(max_value<uint64_t>());
+  bigmax *= max_value<uint64_t>();
+  EXPECT_EQ("fffffffffffffffe0000000000000001", fmt::format("{}", bigmax));
+}
+
+TEST(BigIntTest, Accumulator) {
+  fmt::detail::accumulator acc;
+  EXPECT_EQ(acc.lower, 0);
+  EXPECT_EQ(acc.upper, 0);
+  acc.upper = 12;
+  acc.lower = 34;
+  EXPECT_EQ(static_cast<uint32_t>(acc), 34);
+  acc += 56;
+  EXPECT_EQ(acc.lower, 90);
+  acc += fmt::detail::max_value<uint64_t>();
+  EXPECT_EQ(acc.upper, 13);
+  EXPECT_EQ(acc.lower, 89);
+  acc >>= 32;
+  EXPECT_EQ(acc.upper, 0);
+  EXPECT_EQ(acc.lower, 13 * 0x100000000);
+}
+
+TEST(BigIntTest, Square) {
+  bigint n0(0);
+  n0.square();
+  EXPECT_EQ("0", fmt::format("{}", n0));
+  bigint n1(0x100);
+  n1.square();
+  EXPECT_EQ("10000", fmt::format("{}", n1));
+  bigint n2(0xfffffffff);
+  n2.square();
+  EXPECT_EQ("ffffffffe000000001", fmt::format("{}", n2));
+  bigint n3(max_value<uint64_t>());
+  n3.square();
+  EXPECT_EQ("fffffffffffffffe0000000000000001", fmt::format("{}", n3));
+  bigint n4;
+  n4.assign_pow10(10);
+  EXPECT_EQ("2540be400", fmt::format("{}", n4));
+}
+
+TEST(BigIntTest, DivModAssignZeroDivisor) {
+  bigint zero(0);
+  EXPECT_THROW(bigint(0).divmod_assign(zero), assertion_failure);
+  EXPECT_THROW(bigint(42).divmod_assign(zero), assertion_failure);
+}
+
+TEST(BigIntTest, DivModAssignSelf) {
+  bigint n(100);
+  EXPECT_THROW(n.divmod_assign(n), assertion_failure);
+}
+
+TEST(BigIntTest, DivModAssignUnaligned) {
+  // (42 << 340) / pow(10, 100):
+  bigint n1(42);
+  n1 <<= 340;
+  bigint n2;
+  n2.assign_pow10(100);
+  int result = n1.divmod_assign(n2);
+  EXPECT_EQ(result, 9406);
+  EXPECT_EQ("10f8353019583bfc29ffc8f564e1b9f9d819dbb4cf783e4507eca1539220p96",
+            fmt::format("{}", n1));
+}
+
+TEST(BigIntTest, DivModAssign) {
+  // 100 / 10:
+  bigint n1(100);
+  int result = n1.divmod_assign(bigint(10));
+  EXPECT_EQ(result, 10);
+  EXPECT_EQ("0", fmt::format("{}", n1));
+  // pow(10, 100) / (42 << 320):
+  n1.assign_pow10(100);
+  result = n1.divmod_assign(bigint(42) <<= 320);
+  EXPECT_EQ(result, 111);
+  EXPECT_EQ("13ad2594c37ceb0b2784c4ce0bf38ace408e211a7caab24308a82e8f10p96",
+            fmt::format("{}", n1));
+  // 42 / 100:
+  bigint n2(42);
+  n1.assign_pow10(2);
+  result = n2.divmod_assign(n1);
+  EXPECT_EQ(result, 0);
+  EXPECT_EQ("2a", fmt::format("{}", n2));
+}
+
+template <bool is_iec559> void run_double_tests() {
   fmt::print("warning: double is not IEC559, skipping FP tests\n");
 }
 
-template <>
-void test_construct_from_double<true>() {
-  auto v = fp(1.23);
-  EXPECT_EQ(v.f, 0x13ae147ae147aeu);
-  EXPECT_EQ(v.e, -52);
+template <> void run_double_tests<true>() {
+  // Construct from double.
+  EXPECT_EQ(fp(1.23), fp(0x13ae147ae147aeu, -52));
 }
 
-TEST(FPTest, ConstructFromDouble) {
-  test_construct_from_double<std::numeric_limits<double>::is_iec559>();
+TEST(FPTest, DoubleTests) {
+  run_double_tests<std::numeric_limits<double>::is_iec559>();
 }
 
 TEST(FPTest, Normalize) {
-  auto v = fp(0xbeef, 42);
-  v.normalize();
-  EXPECT_EQ(0xbeef000000000000, v.f);
-  EXPECT_EQ(-6, v.e);
-}
-
-TEST(FPTest, ComputeBoundariesSubnormal) {
-  auto v = fp(0xbeef, 42);
-  fp lower, upper;
-  v.compute_boundaries(lower, upper);
-  EXPECT_EQ(0xbeee800000000000, lower.f);
-  EXPECT_EQ(-6, lower.e);
-  EXPECT_EQ(0xbeef800000000000, upper.f);
-  EXPECT_EQ(-6, upper.e);
-}
-
-TEST(FPTest, ComputeBoundaries) {
-  auto v = fp(0x10000000000000, 42);
-  fp lower, upper;
-  v.compute_boundaries(lower, upper);
-  EXPECT_EQ(0x7ffffffffffffe00, lower.f);
-  EXPECT_EQ(31, lower.e);
-  EXPECT_EQ(0x8000000000000400, upper.f);
-  EXPECT_EQ(31, upper.e);
-}
-
-TEST(FPTest, Subtract) {
-  auto v = fp(123, 1) - fp(102, 1);
-  EXPECT_EQ(v.f, 21u);
-  EXPECT_EQ(v.e, 1);
+  const auto v = fp(0xbeef, 42);
+  auto normalized = normalize(v);
+  EXPECT_EQ(0xbeef000000000000, normalized.f);
+  EXPECT_EQ(-6, normalized.e);
 }
 
 TEST(FPTest, Multiply) {
@@ -91,56 +212,140 @@ TEST(FPTest, Multiply) {
 }
 
 TEST(FPTest, GetCachedPower) {
-  typedef std::numeric_limits<double> limits;
+  using limits = std::numeric_limits<double>;
   for (auto exp = limits::min_exponent; exp <= limits::max_exponent; ++exp) {
     int dec_exp = 0;
-    auto fp = fmt::internal::get_cached_power(exp, dec_exp);
-    EXPECT_LE(exp, fp.e);
-    int dec_exp_step = 8;
-    EXPECT_LE(fp.e, exp + dec_exp_step * log2(10));
-    EXPECT_DOUBLE_EQ(pow(10, dec_exp), ldexp(fp.f, fp.e));
+    auto fp = fmt::detail::get_cached_power(exp, dec_exp);
+    bigint exact, cache(fp.f);
+    if (dec_exp >= 0) {
+      exact.assign_pow10(dec_exp);
+      if (fp.e <= 0)
+        exact <<= -fp.e;
+      else
+        cache <<= fp.e;
+      exact.align(cache);
+      cache.align(exact);
+      auto exact_str = fmt::format("{}", exact);
+      auto cache_str = fmt::format("{}", cache);
+      EXPECT_EQ(exact_str.size(), cache_str.size());
+      EXPECT_EQ(exact_str.substr(0, 15), cache_str.substr(0, 15));
+      int diff = cache_str[15] - exact_str[15];
+      if (diff == 1)
+        EXPECT_GT(exact_str[16], '8');
+      else
+        EXPECT_EQ(diff, 0);
+    } else {
+      cache.assign_pow10(-dec_exp);
+      cache *= fp.f + 1;  // Inexact check.
+      exact.assign(1);
+      exact <<= -fp.e;
+      exact.align(cache);
+      auto exact_str = fmt::format("{}", exact);
+      auto cache_str = fmt::format("{}", cache);
+      EXPECT_EQ(exact_str.size(), cache_str.size());
+      EXPECT_EQ(exact_str.substr(0, 16), cache_str.substr(0, 16));
+    }
   }
 }
 
-TEST(FPTest, Grisu2FormatCompilesWithNonIEEEDouble) {
+TEST(FPTest, DragonboxMaxK) {
+  using fmt::detail::dragonbox::floor_log10_pow2;
+  using float_info = fmt::detail::dragonbox::float_info<float>;
+  EXPECT_EQ(fmt::detail::const_check(float_info::max_k),
+            float_info::kappa - floor_log10_pow2(float_info::min_exponent -
+                                                 float_info::significand_bits));
+  using double_info = fmt::detail::dragonbox::float_info<double>;
+  EXPECT_EQ(
+      fmt::detail::const_check(double_info::max_k),
+      double_info::kappa - floor_log10_pow2(double_info::min_exponent -
+                                            double_info::significand_bits));
+}
+
+TEST(FPTest, GetRoundDirection) {
+  using fmt::detail::get_round_direction;
+  using fmt::detail::round_direction;
+  EXPECT_EQ(round_direction::down, get_round_direction(100, 50, 0));
+  EXPECT_EQ(round_direction::up, get_round_direction(100, 51, 0));
+  EXPECT_EQ(round_direction::down, get_round_direction(100, 40, 10));
+  EXPECT_EQ(round_direction::up, get_round_direction(100, 60, 10));
+  for (size_t i = 41; i < 60; ++i)
+    EXPECT_EQ(round_direction::unknown, get_round_direction(100, i, 10));
+  uint64_t max = max_value<uint64_t>();
+  EXPECT_THROW(get_round_direction(100, 100, 0), assertion_failure);
+  EXPECT_THROW(get_round_direction(100, 0, 100), assertion_failure);
+  EXPECT_THROW(get_round_direction(100, 0, 50), assertion_failure);
+  // Check that remainder + error doesn't overflow.
+  EXPECT_EQ(round_direction::up, get_round_direction(max, max - 1, 2));
+  // Check that 2 * (remainder + error) doesn't overflow.
+  EXPECT_EQ(round_direction::unknown,
+            get_round_direction(max, max / 2 + 1, max / 2));
+  // Check that remainder - error doesn't overflow.
+  EXPECT_EQ(round_direction::unknown, get_round_direction(100, 40, 41));
+  // Check that 2 * (remainder - error) doesn't overflow.
+  EXPECT_EQ(round_direction::up, get_round_direction(max, max - 1, 1));
+}
+
+TEST(FPTest, FixedHandler) {
+  struct handler : fmt::detail::fixed_handler {
+    char buffer[10];
+    handler(int prec = 0) : fmt::detail::fixed_handler() {
+      buf = buffer;
+      precision = prec;
+    }
+  };
+  int exp = 0;
+  handler().on_digit('0', 100, 99, 0, exp, false);
+  EXPECT_THROW(handler().on_digit('0', 100, 100, 0, exp, false),
+               assertion_failure);
+  namespace digits = fmt::detail::digits;
+  EXPECT_EQ(handler(1).on_digit('0', 100, 10, 10, exp, false), digits::error);
+  // Check that divisor - error doesn't overflow.
+  EXPECT_EQ(handler(1).on_digit('0', 100, 10, 101, exp, false), digits::error);
+  // Check that 2 * error doesn't overflow.
+  uint64_t max = max_value<uint64_t>();
+  EXPECT_EQ(handler(1).on_digit('0', max, 10, max - 1, exp, false),
+            digits::error);
+}
+
+TEST(FPTest, GrisuFormatCompilesWithNonIEEEDouble) {
   fmt::memory_buffer buf;
-  grisu2_format(4.2f, buf, fmt::core_format_specs());
+  format_float(0.42, -1, fmt::detail::float_specs(), buf);
 }
 
-template <typename T>
-struct ValueExtractor: fmt::internal::function<T> {
-  T operator()(T value) {
-    return value;
-  }
+template <typename T> struct value_extractor {
+  T operator()(T value) { return value; }
 
-  template <typename U>
-  FMT_NORETURN T operator()(U) {
+  template <typename U> FMT_NORETURN T operator()(U) {
     throw std::runtime_error(fmt::format("invalid type {}", typeid(U).name()));
   }
+
+#if FMT_USE_INT128
+  // Apple Clang does not define typeid for __int128_t and __uint128_t.
+  FMT_NORETURN T operator()(fmt::detail::int128_t) {
+    throw std::runtime_error("invalid type __int128_t");
+  }
+
+  FMT_NORETURN T operator()(fmt::detail::uint128_t) {
+    throw std::runtime_error("invalid type __uint128_t");
+  }
+#endif
 };
 
 TEST(FormatTest, ArgConverter) {
-  long long value = std::numeric_limits<long long>::max();
-  auto arg = fmt::internal::make_arg<fmt::format_context>(value);
-  visit(fmt::internal::arg_converter<long long, fmt::format_context>(arg, 'd'),
-        arg);
-  EXPECT_EQ(value, visit(ValueExtractor<long long>(), arg));
-}
-
-TEST(FormatTest, FormatNegativeNaN) {
-  double nan = std::numeric_limits<double>::quiet_NaN();
-  if (std::signbit(-nan))
-    EXPECT_EQ("-nan", fmt::format("{}", -nan));
-  else
-    fmt::print("Warning: compiler doesn't handle negative NaN correctly");
+  long long value = max_value<long long>();
+  auto arg = fmt::detail::make_arg<fmt::format_context>(value);
+  fmt::visit_format_arg(
+      fmt::detail::arg_converter<long long, fmt::format_context>(arg, 'd'),
+      arg);
+  EXPECT_EQ(value, fmt::visit_format_arg(value_extractor<long long>(), arg));
 }
 
 TEST(FormatTest, StrError) {
-  char *message = FMT_NULL;
+  char* message = nullptr;
   char buffer[BUFFER_SIZE];
-  EXPECT_ASSERT(fmt::safe_strerror(EDOM, message = FMT_NULL, 0),
+  EXPECT_ASSERT(fmt::detail::safe_strerror(EDOM, message = nullptr, 0),
                 "invalid buffer");
-  EXPECT_ASSERT(fmt::safe_strerror(EDOM, message = buffer, 0),
+  EXPECT_ASSERT(fmt::detail::safe_strerror(EDOM, message = buffer, 0),
                 "invalid buffer");
   buffer[0] = 'x';
 #if defined(_GNU_SOURCE) && !defined(__COVERITY__)
@@ -151,17 +356,19 @@ TEST(FormatTest, StrError) {
   int error_code = EDOM;
 #endif
 
-  int result = fmt::safe_strerror(error_code, message = buffer, BUFFER_SIZE);
+  int result =
+      fmt::detail::safe_strerror(error_code, message = buffer, BUFFER_SIZE);
   EXPECT_EQ(result, 0);
-  std::size_t message_size = std::strlen(message);
+  size_t message_size = std::strlen(message);
   EXPECT_GE(BUFFER_SIZE - 1u, message_size);
   EXPECT_EQ(get_system_error(error_code), message);
 
   // safe_strerror never uses buffer on MinGW.
-#ifndef __MINGW32__
-  result = fmt::safe_strerror(error_code, message = buffer, message_size);
+#if !defined(__MINGW32__) && !defined(__sun)
+  result =
+      fmt::detail::safe_strerror(error_code, message = buffer, message_size);
   EXPECT_EQ(ERANGE, result);
-  result = fmt::safe_strerror(error_code, message = buffer, 1);
+  result = fmt::detail::safe_strerror(error_code, message = buffer, 1);
   EXPECT_EQ(buffer, message);  // Message should point to buffer.
   EXPECT_EQ(ERANGE, result);
   EXPECT_STREQ("", message);
@@ -173,74 +380,67 @@ TEST(FormatTest, FormatErrorCode) {
   {
     fmt::memory_buffer buffer;
     format_to(buffer, "garbage");
-    fmt::format_error_code(buffer, 42, "test");
+    fmt::detail::format_error_code(buffer, 42, "test");
     EXPECT_EQ("test: " + msg, to_string(buffer));
   }
   {
     fmt::memory_buffer buffer;
-    std::string prefix(
-        fmt::inline_buffer_size - msg.size() - sep.size() + 1, 'x');
-    fmt::format_error_code(buffer, 42, prefix);
+    std::string prefix(fmt::inline_buffer_size - msg.size() - sep.size() + 1,
+                       'x');
+    fmt::detail::format_error_code(buffer, 42, prefix);
     EXPECT_EQ(msg, to_string(buffer));
   }
   int codes[] = {42, -1};
-  for (std::size_t i = 0, n = sizeof(codes) / sizeof(*codes); i < n; ++i) {
+  for (size_t i = 0, n = sizeof(codes) / sizeof(*codes); i < n; ++i) {
     // Test maximum buffer size.
     msg = fmt::format("error {}", codes[i]);
     fmt::memory_buffer buffer;
-    std::string prefix(
-        fmt::inline_buffer_size - msg.size() - sep.size(), 'x');
-    fmt::format_error_code(buffer, codes[i], prefix);
+    std::string prefix(fmt::inline_buffer_size - msg.size() - sep.size(), 'x');
+    fmt::detail::format_error_code(buffer, codes[i], prefix);
     EXPECT_EQ(prefix + sep + msg, to_string(buffer));
-    std::size_t size = fmt::inline_buffer_size;
+    size_t size = fmt::inline_buffer_size;
     EXPECT_EQ(size, buffer.size());
     buffer.resize(0);
     // Test with a message that doesn't fit into the buffer.
     prefix += 'x';
-    fmt::format_error_code(buffer, codes[i], prefix);
+    fmt::detail::format_error_code(buffer, codes[i], prefix);
     EXPECT_EQ(msg, to_string(buffer));
   }
 }
 
 TEST(FormatTest, CountCodePoints) {
-  EXPECT_EQ(4, fmt::internal::count_code_points(fmt::u8string_view("ёжик")));
+  EXPECT_EQ(4,
+            fmt::detail::count_code_points(
+                fmt::basic_string_view<fmt::detail::char8_type>(
+                    reinterpret_cast<const fmt::detail::char8_type*>("ёжик"))));
 }
 
-TEST(ColorsTest, Colors) {
-  EXPECT_WRITE(stdout, fmt::print(fg(fmt::rgb(255, 20, 30)), "rgb(255,20,30)"),
-               "\x1b[38;2;255;020;030mrgb(255,20,30)\x1b[0m");
-  EXPECT_WRITE(stdout, fmt::print(fg(fmt::color::blue), "blue"),
-               "\x1b[38;2;000;000;255mblue\x1b[0m");
-  EXPECT_WRITE(
-      stdout,
-      fmt::print(fg(fmt::color::blue) | bg(fmt::color::red), "two color"),
-      "\x1b[38;2;000;000;255m\x1b[48;2;255;000;000mtwo color\x1b[0m");
-  EXPECT_WRITE(stdout, fmt::print(fmt::emphasis::bold, "bold"),
-               "\x1b[1mbold\x1b[0m");
-  EXPECT_WRITE(stdout, fmt::print(fmt::emphasis::italic, "italic"),
-               "\x1b[3mitalic\x1b[0m");
-  EXPECT_WRITE(stdout, fmt::print(fmt::emphasis::underline, "underline"),
-               "\x1b[4munderline\x1b[0m");
-  EXPECT_WRITE(stdout,
-               fmt::print(fmt::emphasis::strikethrough, "strikethrough"),
-               "\x1b[9mstrikethrough\x1b[0m");
-  EXPECT_WRITE(
-      stdout,
-      fmt::print(fg(fmt::color::blue) | fmt::emphasis::bold, "blue/bold"),
-      "\x1b[1m\x1b[38;2;000;000;255mblue/bold\x1b[0m");
-  EXPECT_WRITE(stderr, fmt::print(stderr, fmt::emphasis::bold, "bold error"),
-               "\x1b[1mbold error\x1b[0m");
-  EXPECT_WRITE(stderr, fmt::print(stderr, fg(fmt::color::blue), "blue log"),
-                 "\x1b[38;2;000;000;255mblue log\x1b[0m");
-  EXPECT_WRITE(stdout, fmt::print(fmt::text_style(), "hi"), "hi");
-  EXPECT_WRITE(stdout, fmt::print(fg(fmt::terminal_color::red), "tred"),
-               "\x1b[31mtred\x1b[0m");
-  EXPECT_WRITE(stdout, fmt::print(bg(fmt::terminal_color::cyan), "tcyan"),
-               "\x1b[46mtcyan\x1b[0m");
-  EXPECT_WRITE(stdout,
-               fmt::print(fg(fmt::terminal_color::bright_green), "tbgreen"),
-               "\x1b[92mtbgreen\x1b[0m");
-  EXPECT_WRITE(stdout,
-               fmt::print(bg(fmt::terminal_color::bright_magenta), "tbmagenta"),
-               "\x1b[105mtbmagenta\x1b[0m");
+// Tests fmt::detail::count_digits for integer type Int.
+template <typename Int> void test_count_digits() {
+  for (Int i = 0; i < 10; ++i) EXPECT_EQ(1u, fmt::detail::count_digits(i));
+  for (Int i = 1, n = 1, end = max_value<Int>() / 10; n <= end; ++i) {
+    n *= 10;
+    EXPECT_EQ(i, fmt::detail::count_digits(n - 1));
+    EXPECT_EQ(i + 1, fmt::detail::count_digits(n));
+  }
 }
+
+TEST(UtilTest, CountDigits) {
+  test_count_digits<uint32_t>();
+  test_count_digits<uint64_t>();
+}
+
+TEST(UtilTest, WriteFallbackUIntPtr) {
+  std::string s;
+  fmt::detail::write_ptr<char>(
+      std::back_inserter(s),
+      fmt::detail::fallback_uintptr(reinterpret_cast<void*>(0xface)), nullptr);
+  EXPECT_EQ(s, "0xface");
+}
+
+#ifdef _WIN32
+TEST(UtilTest, WriteConsoleSignature) {
+  decltype(WriteConsoleW)* p = fmt::detail::WriteConsoleW;
+  (void)p;
+}
+#endif

test/fuzzing/.gitignore

@@ -0,0 +1,3 @@
+# ignore artifacts from the build.sh script
+build-*/
+

test/fuzzing/CMakeLists.txt

@@ -0,0 +1,30 @@
+# Copyright (c) 2019, Paul Dreik
+# License: see LICENSE.rst in the fmt root directory
+
+# Link in the main function. Useful for reproducing, kcov, gdb, afl, valgrind.
+# (Note that libFuzzer can also reproduce, just pass it the files.)
+option(FMT_FUZZ_LINKMAIN "Enables the reproduce mode, instead of libFuzzer" On)
+
+# For oss-fuzz - insert $LIB_FUZZING_ENGINE into the link flags, but only for
+# the fuzz targets, otherwise the CMake configuration step fails.
+set(FMT_FUZZ_LDFLAGS "" CACHE STRING "LDFLAGS for the fuzz targets")
+
+# Adds a binary for reproducing, i.e. no fuzzing, just enables replaying data
+# through the fuzzers.
+function(add_fuzzer source)
+  get_filename_component(basename ${source} NAME_WE)
+  set(name ${basename}-fuzzer)
+  add_executable(${name} ${source} fuzzer-common.h)
+  if (FMT_FUZZ_LINKMAIN)
+    target_sources(${name} PRIVATE main.cc)
+  endif ()
+  target_link_libraries(${name} PRIVATE fmt)
+  if (FMT_FUZZ_LDFLAGS)
+    target_link_libraries(${name} PRIVATE ${FMT_FUZZ_LDFLAGS})
+  endif ()
+  target_compile_features(${name} PRIVATE cxx_generic_lambdas)
+endfunction()
+
+foreach (source chrono-duration.cc float.cc named-arg.cc one-arg.cc two-args.cc)
+  add_fuzzer(${source})
+endforeach ()

test/fuzzing/README.md

@@ -0,0 +1,25 @@
+# Running the fuzzers locally
+
+There is a [helper script](build.sh) to build the fuzzers, which has only been
+tested on Debian and Ubuntu linux so far. There should be no problems fuzzing on
+Windows (using clang>=8) or on Mac, but the script will probably not work out of
+the box.
+
+Something along
+```sh
+mkdir build
+cd build
+export CXX=clang++
+export CXXFLAGS="-fsanitize=fuzzer-no-link -DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION= -g"
+cmake .. -DFMT_SAFE_DURATION_CAST=On -DFMT_FUZZ=On -DFMT_FUZZ_LINKMAIN=Off -DFMT_FUZZ_LDFLAGS="-fsanitize=fuzzer"
+cmake --build .
+```
+should work to build the fuzzers for all platforms which clang supports.
+
+Execute a fuzzer with for instance
+```sh
+cd build
+export UBSAN_OPTIONS=halt_on_error=1
+mkdir out_chrono
+bin/fuzzer_chrono_duration out_chrono
+```

test/fuzzing/build.sh

@@ -0,0 +1,88 @@
+#!/bin/sh
+#
+# Creates fuzzer builds of various kinds
+# - oss-fuzz emulated mode (makes sure a simulated invocation by oss-fuzz works)
+# - libFuzzer build (you will need clang)
+# - afl build (you will need afl)
+#
+#
+# Copyright (c) 2019 Paul Dreik
+#
+# For the license information refer to format.h.
+
+set -e
+me=$(basename $0)
+root=$(readlink -f "$(dirname "$0")/../..")
+
+
+echo $me: root=$root
+
+here=$(pwd)
+
+CXXFLAGSALL="-DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION= -g"
+CMAKEFLAGSALL="$root -GNinja -DCMAKE_BUILD_TYPE=Debug -DFMT_DOC=Off -DFMT_TEST=Off -DFMT_FUZZ=On -DCMAKE_CXX_STANDARD=17"
+
+# For performance analysis of the fuzzers.
+builddir=$here/build-fuzzers-perfanalysis
+mkdir -p $builddir
+cd $builddir
+CXX="ccache g++" CXXFLAGS="$CXXFLAGSALL -g" cmake \
+$CMAKEFLAGSALL \
+-DFMT_FUZZ_LINKMAIN=On \
+-DCMAKE_BUILD_TYPE=Release
+
+cmake --build $builddir
+
+# Builds the fuzzers as oss-fuzz does.
+builddir=$here/build-fuzzers-ossfuzz
+mkdir -p $builddir
+cd $builddir
+CXX="clang++" \
+CXXFLAGS="$CXXFLAGSALL -fsanitize=fuzzer-no-link" cmake \
+cmake $CMAKEFLAGSALL \
+-DFMT_FUZZ_LINKMAIN=Off \
+-DFMT_FUZZ_LDFLAGS="-fsanitize=fuzzer"
+
+cmake --build $builddir
+
+
+# Builds fuzzers for local fuzzing with libfuzzer with asan+usan.
+builddir=$here/build-fuzzers-libfuzzer
+mkdir -p $builddir
+cd $builddir
+CXX="clang++" \
+CXXFLAGS="$CXXFLAGSALL -fsanitize=fuzzer-no-link,address,undefined" cmake \
+cmake $CMAKEFLAGSALL \
+-DFMT_FUZZ_LINKMAIN=Off \
+-DFMT_FUZZ_LDFLAGS="-fsanitize=fuzzer"
+
+cmake --build $builddir
+
+# Builds a fast fuzzer for making coverage fast.
+builddir=$here/build-fuzzers-fast
+mkdir -p $builddir
+cd $builddir
+CXX="clang++" \
+CXXFLAGS="$CXXFLAGSALL -fsanitize=fuzzer-no-link -O3" cmake \
+cmake $CMAKEFLAGSALL \
+-DFMT_FUZZ_LINKMAIN=Off \
+-DFMT_FUZZ_LDFLAGS="-fsanitize=fuzzer" \
+ -DCMAKE_BUILD_TYPE=Release
+
+cmake --build $builddir
+
+
+# Builds fuzzers for local fuzzing with afl.
+builddir=$here/build-fuzzers-afl
+mkdir -p $builddir
+cd $builddir
+CXX="afl-g++" \
+CXXFLAGS="$CXXFLAGSALL -fsanitize=address,undefined" \
+cmake $CMAKEFLAGSALL \
+-DFMT_FUZZ_LINKMAIN=On
+
+cmake --build $builddir
+
+
+echo $me: all good
+

test/fuzzing/chrono-duration.cc

@@ -0,0 +1,135 @@
+// Copyright (c) 2019, Paul Dreik
+// For the license information refer to format.h.
+
+#include <cstdint>
+#include <fmt/chrono.h>
+
+#include "fuzzer-common.h"
+
+template <typename Period, typename Rep>
+void invoke_inner(fmt::string_view format_str, Rep rep) {
+  auto value = std::chrono::duration<Rep, Period>(rep);
+  try {
+#if FMT_FUZZ_FORMAT_TO_STRING
+    std::string message = fmt::format(format_str, value);
+#else
+    fmt::memory_buffer buf;
+    fmt::format_to(buf, format_str, value);
+#endif
+  } catch (std::exception&) {
+  }
+}
+
+// Rep is a duration's representation type.
+template <typename Rep>
+void invoke_outer(const uint8_t* data, size_t size, int period) {
+  // Always use a fixed location of the data.
+  static_assert(sizeof(Rep) <= fixed_size, "fixed size is too small");
+  if (size <= fixed_size + 1) return;
+
+  const Rep rep = assign_from_buf<Rep>(data);
+  data += fixed_size;
+  size -= fixed_size;
+
+  // data is already allocated separately in libFuzzer so reading past the end 
+  // will most likely be detected anyway.
+  const auto format_str = fmt::string_view(as_chars(data), size);
+
+  // yocto, zepto, zetta and yotta are not handled.
+  switch (period) {
+  case 1:
+    invoke_inner<std::atto>(format_str, rep);
+    break;
+  case 2:
+    invoke_inner<std::femto>(format_str, rep);
+    break;
+  case 3:
+    invoke_inner<std::pico>(format_str, rep);
+    break;
+  case 4:
+    invoke_inner<std::nano>(format_str, rep);
+    break;
+  case 5:
+    invoke_inner<std::micro>(format_str, rep);
+    break;
+  case 6:
+    invoke_inner<std::milli>(format_str, rep);
+    break;
+  case 7:
+    invoke_inner<std::centi>(format_str, rep);
+    break;
+  case 8:
+    invoke_inner<std::deci>(format_str, rep);
+    break;
+  case 9:
+    invoke_inner<std::deca>(format_str, rep);
+    break;
+  case 10:
+    invoke_inner<std::kilo>(format_str, rep);
+    break;
+  case 11:
+    invoke_inner<std::mega>(format_str, rep);
+    break;
+  case 12:
+    invoke_inner<std::giga>(format_str, rep);
+    break;
+  case 13:
+    invoke_inner<std::tera>(format_str, rep);
+    break;
+  case 14:
+    invoke_inner<std::peta>(format_str, rep);
+    break;
+  case 15:
+    invoke_inner<std::exa>(format_str, rep);
+    break;
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  if (size <= 4)  return 0;
+
+  const auto representation = data[0];
+  const auto period = data[1];
+  data += 2;
+  size -= 2;
+
+  switch (representation) {
+  case 1:
+    invoke_outer<char>(data, size, period);
+    break;
+  case 2:
+    invoke_outer<signed char>(data, size, period);
+    break;
+  case 3:
+    invoke_outer<unsigned char>(data, size, period);
+    break;
+  case 4:
+    invoke_outer<short>(data, size, period);
+    break;
+  case 5:
+    invoke_outer<unsigned short>(data, size, period);
+    break;
+  case 6:
+    invoke_outer<int>(data, size, period);
+    break;
+  case 7:
+    invoke_outer<unsigned int>(data, size, period);
+    break;
+  case 8:
+    invoke_outer<long>(data, size, period);
+    break;
+  case 9:
+    invoke_outer<unsigned long>(data, size, period);
+    break;
+  case 10:
+    invoke_outer<float>(data, size, period);
+    break;
+  case 11:
+    invoke_outer<double>(data, size, period);
+    break;
+  case 12:
+    invoke_outer<long double>(data, size, period);
+    break;
+  }
+  return 0;
+}

test/fuzzing/float.cc

@@ -0,0 +1,34 @@
+// A fuzzer for floating-point formatter.
+// For the license information refer to format.h.
+
+#include <cstdint>
+#include <cstdlib>
+#include <stdexcept>
+#include <limits>
+#include <fmt/format.h>
+
+#include "fuzzer-common.h"
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  if (size <= sizeof(double) || !std::numeric_limits<double>::is_iec559)
+    return 0;
+
+  auto value = assign_from_buf<double>(data);
+  auto buffer = fmt::memory_buffer();
+  fmt::format_to(buffer, "{}", value);
+
+  // Check a round trip.
+  if (std::isnan(value)) {
+    auto nan = std::signbit(value) ? "-nan" : "nan";
+    if (fmt::string_view(buffer.data(), buffer.size()) != nan)
+      throw std::runtime_error("round trip failure");
+    return 0;
+  }
+  buffer.push_back('\0');
+  char* ptr = nullptr;
+  if (std::strtod(buffer.data(), &ptr) != value)
+    throw std::runtime_error("round trip failure");
+  if (ptr + 1 != buffer.end())
+    throw std::runtime_error("unparsed output");
+  return 0;
+}

test/fuzzing/fuzzer-common.h

@@ -0,0 +1,75 @@
+// Copyright (c) 2019, Paul Dreik
+// For the license information refer to format.h.
+
+#ifndef FUZZER_COMMON_H
+#define FUZZER_COMMON_H
+
+#include <cstdint>      // std::uint8_t
+#include <cstring>      // memcpy
+#include <vector>
+
+#include <fmt/core.h>
+
+// One can format to either a string, or a buffer. The latter is faster, but
+// one may be interested in formatting to a string instead to verify it works
+// as intended. To avoid a combinatoric explosion, select this at compile time
+// instead of dynamically from the fuzz data.
+#define FMT_FUZZ_FORMAT_TO_STRING 0
+
+// If {fmt} is given a buffer that is separately allocated, chances that address
+// sanitizer detects out of bound reads is much higher. However, it slows down
+// the fuzzing.
+#define FMT_FUZZ_SEPARATE_ALLOCATION 1
+
+// The size of the largest possible type in use.
+// To let the the fuzzer mutation be efficient at cross pollinating between
+// different types, use a fixed size format. The same bit pattern, interpreted
+// as another type, is likely interesting.
+constexpr auto fixed_size = 16;
+
+// Casts data to a char pointer.
+template <typename T> inline const char* as_chars(const T* data) {
+  return reinterpret_cast<const char*>(data);
+}
+
+// Casts data to a byte pointer.
+template <typename T> inline const std::uint8_t* as_bytes(const T* data) {
+  return reinterpret_cast<const std::uint8_t*>(data);
+}
+
+// Blits bytes from data to form an (assumed trivially constructible) object
+// of type Item.
+template <class Item> inline Item assign_from_buf(const std::uint8_t* data) {
+  auto item = Item();
+  std::memcpy(&item, data, sizeof(Item));
+  return item;
+}
+
+// Reads a boolean value by looking at the first byte from data.
+template <> inline bool assign_from_buf<bool>(const std::uint8_t* data) {
+  return *data != 0;
+}
+
+struct data_to_string {
+#if FMT_FUZZ_SEPARATE_ALLOCATION
+  std::vector<char> buffer;
+
+  data_to_string(const uint8_t* data, size_t size, bool add_terminator = false)
+      : buffer(size + (add_terminator ? 1 : 0)) {
+    std::memcpy(buffer.data(), data, size);
+  }
+
+  fmt::string_view get() const { return {buffer.data(), buffer.size()}; }
+#else
+  fmt::string_view sv;
+
+  data_to_string(const uint8_t* data, size_t size, bool = false)
+      : str(as_chars(data), size) {}
+
+  fmt::string_view get() const { return sv; }
+#endif
+
+  const char* data() const { return get().data(); }
+};
+
+#endif  // FUZZER_COMMON_H

test/fuzzing/main.cc

@@ -0,0 +1,22 @@
+#include <cassert>
+#include <fstream>
+#include <vector>
+
+#include "fuzzer-common.h"
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size);
+
+int main(int argc, char** argv) {
+  for (int i = 1; i < argc; ++i) {
+    std::ifstream in(argv[i]);
+    assert(in);
+    in.seekg(0, std::ios_base::end);
+    const auto size = in.tellg();
+    assert(size >= 0);
+    in.seekg(0, std::ios_base::beg);
+    std::vector<char> buf(static_cast<size_t>(size));
+    in.read(buf.data(), size);
+    assert(in.gcount() == size);
+    LLVMFuzzerTestOneInput(as_bytes(buf.data()), buf.size());
+  }
+}

test/fuzzing/named-arg.cc

@@ -0,0 +1,100 @@
+// Copyright (c) 2019, Paul Dreik
+// For the license information refer to format.h.
+
+#include <cstdint>
+#include <type_traits>
+#include <vector>
+#include <fmt/chrono.h>
+
+#include "fuzzer-common.h"
+
+template <typename T>
+void invoke_fmt(const uint8_t* data, size_t size, unsigned arg_name_size) {
+  static_assert(sizeof(T) <= fixed_size, "fixed_size too small");
+  if (size <= fixed_size) return;
+  const T value = assign_from_buf<T>(data);
+  data += fixed_size;
+  size -= fixed_size;
+
+  if (arg_name_size <= 0 || arg_name_size >= size) return;
+  data_to_string arg_name(data, arg_name_size, true);
+  data += arg_name_size;
+  size -= arg_name_size;
+
+  data_to_string format_str(data, size);
+  try {
+#if FMT_FUZZ_FORMAT_TO_STRING
+    std::string message =
+      fmt::format(format_str.get(), fmt::arg(arg_name.data(), value));
+#else
+    fmt::memory_buffer out;
+    fmt::format_to(out, format_str.get(), fmt::arg(arg_name.data(), value));
+#endif
+  } catch (std::exception&) {
+  }
+}
+
+// For dynamic dispatching to an explicit instantiation.
+template <typename Callback> void invoke(int type, Callback callback) {
+  switch (type) {
+  case 0:
+    callback(bool());
+    break;
+  case 1:
+    callback(char());
+    break;
+  case 2:
+    using sc = signed char;
+    callback(sc());
+    break;
+  case 3:
+    using uc = unsigned char;
+    callback(uc());
+    break;
+  case 4:
+    callback(short());
+    break;
+  case 5:
+    using us = unsigned short;
+    callback(us());
+    break;
+  case 6:
+    callback(int());
+    break;
+  case 7:
+    callback(unsigned());
+    break;
+  case 8:
+    callback(long());
+    break;
+  case 9:
+    using ul = unsigned long;
+    callback(ul());
+    break;
+  case 10:
+    callback(float());
+    break;
+  case 11:
+    callback(double());
+    break;
+  case 12:
+    using LD = long double;
+    callback(LD());
+    break;
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  if (size <= 3) return 0;
+
+  // Switch types depending on the first byte of the input.
+  const auto type = data[0] & 0x0F;
+  const unsigned arg_name_size = (data[0] & 0xF0) >> 4;
+  data++;
+  size--;
+
+  invoke(type, [=](auto arg) {
+    invoke_fmt<decltype(arg)>(data, size, arg_name_size);
+  });
+  return 0;
+}

test/fuzzing/one-arg.cc

@@ -0,0 +1,91 @@
+// Copyright (c) 2019, Paul Dreik
+// For the license information refer to format.h.
+
+#include <cstdint>
+#include <exception>
+#include <fmt/chrono.h>
+
+#include "fuzzer-common.h"
+
+template <typename T, typename Repr>
+const T* from_repr(const Repr& r) { return &r; }
+
+template <>
+const std::tm* from_repr<std::tm>(const std::time_t& t) {
+  return std::localtime(&t);
+}
+
+template <typename T, typename Repr = T>
+void invoke_fmt(const uint8_t* data, size_t size) {
+  static_assert(sizeof(Repr) <= fixed_size, "Nfixed is too small");
+  if (size <= fixed_size) return;
+  auto repr = assign_from_buf<Repr>(data);
+  const T* value = from_repr<T>(repr);
+  if (!value) return;
+  data += fixed_size;
+  size -= fixed_size;
+  data_to_string format_str(data, size);
+  try {
+#if FMT_FUZZ_FORMAT_TO_STRING
+    std::string message = fmt::format(format_str.get(), *value);
+#else
+    fmt::memory_buffer message;
+    fmt::format_to(message, format_str.get(), *value);
+#endif
+  } catch (std::exception&) {
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  if (size <= 3) return 0;
+
+  const auto first = data[0];
+  data++;
+  size--;
+
+  switch (first) {
+  case 0:
+    invoke_fmt<bool>(data, size);
+    break;
+  case 1:
+    invoke_fmt<char>(data, size);
+    break;
+  case 2:
+    invoke_fmt<unsigned char>(data, size);
+    break;
+  case 3:
+    invoke_fmt<signed char>(data, size);
+    break;
+  case 4:
+    invoke_fmt<short>(data, size);
+    break;
+  case 5:
+    invoke_fmt<unsigned short>(data, size);
+    break;
+  case 6:
+    invoke_fmt<int>(data, size);
+    break;
+  case 7:
+    invoke_fmt<unsigned int>(data, size);
+    break;
+  case 8:
+    invoke_fmt<long>(data, size);
+    break;
+  case 9:
+    invoke_fmt<unsigned long>(data, size);
+    break;
+  case 10:
+    invoke_fmt<float>(data, size);
+    break;
+  case 11:
+    invoke_fmt<double>(data, size);
+    break;
+  case 12:
+    invoke_fmt<long double>(data, size);
+    break;
+  case 13:
+    invoke_fmt<std::tm, std::time_t>(data, size);
+    break;
+  }
+  return 0;
+}

test/fuzzing/two-args.cc

@@ -0,0 +1,105 @@
+// Copyright (c) 2019, Paul Dreik
+// For the license information refer to format.h.
+
+#include <cstdint>
+#include <exception>
+#include <string>
+#include <fmt/format.h>
+
+#include "fuzzer-common.h"
+
+template <typename Item1, typename Item2>
+void invoke_fmt(const uint8_t* data, size_t size) {
+  static_assert(sizeof(Item1) <= fixed_size, "size1 exceeded");
+  static_assert(sizeof(Item2) <= fixed_size, "size2 exceeded");
+  if (size <= fixed_size + fixed_size) return;
+
+  const Item1 item1 = assign_from_buf<Item1>(data);
+  data += fixed_size;
+  size -= fixed_size;
+
+  const Item2 item2 = assign_from_buf<Item2>(data);
+  data += fixed_size;
+  size -= fixed_size;
+
+  auto format_str = fmt::string_view(as_chars(data), size);
+#if FMT_FUZZ_FORMAT_TO_STRING
+  std::string message = fmt::format(format_str, item1, item2);
+#else
+  fmt::memory_buffer message;
+  fmt::format_to(message, format_str, item1, item2);
+#endif
+}
+
+// For dynamic dispatching to an explicit instantiation.
+template <typename Callback> void invoke(int index, Callback callback) {
+  switch (index) {
+  case 0:
+    callback(bool());
+    break;
+  case 1:
+    callback(char());
+    break;
+  case 2:
+    using sc = signed char;
+    callback(sc());
+    break;
+  case 3:
+    using uc = unsigned char;
+    callback(uc());
+    break;
+  case 4:
+    callback(short());
+    break;
+  case 5:
+    using us = unsigned short;
+    callback(us());
+    break;
+  case 6:
+    callback(int());
+    break;
+  case 7:
+    callback(unsigned());
+    break;
+  case 8:
+    callback(long());
+    break;
+  case 9:
+    using ul = unsigned long;
+    callback(ul());
+    break;
+  case 10:
+    callback(float());
+    break;
+  case 11:
+    callback(double());
+    break;
+  case 12:
+    using LD = long double;
+    callback(LD());
+    break;
+  case 13:
+    using ptr = void*;
+    callback(ptr());
+    break;
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  if (size <= 3) return 0;
+
+  // Switch types depending on the first byte of the input.
+  const auto type1 = data[0] & 0x0F;
+  const auto type2 = (data[0] & 0xF0) >> 4;
+  data++;
+  size--;
+  try {
+    invoke(type1, [=](auto param1) {
+      invoke(type2, [=](auto param2) {
+        invoke_fmt<decltype(param1), decltype(param2)>(data, size);
+      });
+    });
+  } catch (std::exception&) {
+  }
+  return 0;
+}

test/gtest-extra-test.cc

@@ -7,23 +7,23 @@
 
 #include "gtest-extra.h"
 
-#include <cstring>
-#include <algorithm>
-#include <stdexcept>
 #include <gtest/gtest-spi.h>
 
+#include <algorithm>
+#include <cstring>
+#include <memory>
+#include <stdexcept>
+
 #if defined(_WIN32) && !defined(__MINGW32__)
-# include <crtdbg.h>  // for _CrtSetReportMode
-#endif  // _WIN32
+#  include <crtdbg.h>  // for _CrtSetReportMode
+#endif                 // _WIN32
 
 #include "util.h"
 
-using testing::internal::scoped_ptr;
-
 namespace {
 
 // This is used to suppress coverity warnings about untrusted values.
-std::string sanitize(const std::string &s) {
+std::string sanitize(const std::string& s) {
   std::string result;
   for (std::string::const_iterator i = s.begin(), end = s.end(); i != end; ++i)
     result.push_back(static_cast<char>(*i & 0xff));
@@ -53,11 +53,9 @@ int SingleEvaluationTest::b_;
 
 void do_nothing() {}
 
-void throw_exception() {
-  throw std::runtime_error("test");
-}
+FMT_NORETURN void throw_exception() { throw std::runtime_error("test"); }
 
-void throw_system_error() {
+FMT_NORETURN void throw_system_error() {
   throw fmt::system_error(EDOM, "test");
 }
 
@@ -72,43 +70,42 @@ TEST_F(SingleEvaluationTest, FailedEXPECT_THROW_MSG) {
 // Tests that when EXPECT_SYSTEM_ERROR fails, it evaluates its message argument
 // exactly once.
 TEST_F(SingleEvaluationTest, FailedEXPECT_SYSTEM_ERROR) {
-  EXPECT_NONFATAL_FAILURE(
-      EXPECT_SYSTEM_ERROR(throw_system_error(), EDOM, p_++), "01234");
-  EXPECT_EQ(s_ + 1, p_);
-}
-
-// Tests that when EXPECT_WRITE fails, it evaluates its message argument
-// exactly once.
-TEST_F(SingleEvaluationTest, FailedEXPECT_WRITE) {
-  EXPECT_NONFATAL_FAILURE(
-      EXPECT_WRITE(stdout, std::printf("test"), p_++), "01234");
+  EXPECT_NONFATAL_FAILURE(EXPECT_SYSTEM_ERROR(throw_system_error(), EDOM, p_++),
+                          "01234");
   EXPECT_EQ(s_ + 1, p_);
 }
 
 // Tests that assertion arguments are evaluated exactly once.
 TEST_F(SingleEvaluationTest, ExceptionTests) {
   // successful EXPECT_THROW_MSG
-  EXPECT_THROW_MSG({  // NOLINT
-    a_++;
-    throw_exception();
-  }, std::exception, (b_++, "test"));
+  EXPECT_THROW_MSG(
+      {  // NOLINT
+        a_++;
+        throw_exception();
+      },
+      std::exception, (b_++, "test"));
   EXPECT_EQ(1, a_);
   EXPECT_EQ(1, b_);
 
   // failed EXPECT_THROW_MSG, throws different type
-  EXPECT_NONFATAL_FAILURE(EXPECT_THROW_MSG({  // NOLINT
-    a_++;
-    throw_exception();
-  }, std::logic_error, (b_++, "test")), "throws a different type");
+  EXPECT_NONFATAL_FAILURE(EXPECT_THROW_MSG(
+                              {  // NOLINT
+                                a_++;
+                                throw_exception();
+                              },
+                              std::logic_error, (b_++, "test")),
+                          "throws a different type");
   EXPECT_EQ(2, a_);
   EXPECT_EQ(2, b_);
 
   // failed EXPECT_THROW_MSG, throws an exception with different message
-  EXPECT_NONFATAL_FAILURE(EXPECT_THROW_MSG({  // NOLINT
-    a_++;
-    throw_exception();
-  }, std::exception, (b_++, "other")),
-      "throws an exception with a different message");
+  EXPECT_NONFATAL_FAILURE(EXPECT_THROW_MSG(
+                              {  // NOLINT
+                                a_++;
+                                throw_exception();
+                              },
+                              std::exception, (b_++, "other")),
+                          "throws an exception with a different message");
   EXPECT_EQ(3, a_);
   EXPECT_EQ(3, b_);
 
@@ -121,56 +118,97 @@ TEST_F(SingleEvaluationTest, ExceptionTests) {
 
 TEST_F(SingleEvaluationTest, SystemErrorTests) {
   // successful EXPECT_SYSTEM_ERROR
-  EXPECT_SYSTEM_ERROR({  // NOLINT
-    a_++;
-    throw_system_error();
-  }, EDOM, (b_++, "test"));
+  EXPECT_SYSTEM_ERROR(
+      {  // NOLINT
+        a_++;
+        throw_system_error();
+      },
+      EDOM, (b_++, "test"));
   EXPECT_EQ(1, a_);
   EXPECT_EQ(1, b_);
 
   // failed EXPECT_SYSTEM_ERROR, throws different type
-  EXPECT_NONFATAL_FAILURE(EXPECT_SYSTEM_ERROR({  // NOLINT
-    a_++;
-    throw_exception();
-  }, EDOM, (b_++, "test")), "throws a different type");
+  EXPECT_NONFATAL_FAILURE(EXPECT_SYSTEM_ERROR(
+                              {  // NOLINT
+                                a_++;
+                                throw_exception();
+                              },
+                              EDOM, (b_++, "test")),
+                          "throws a different type");
   EXPECT_EQ(2, a_);
   EXPECT_EQ(2, b_);
 
   // failed EXPECT_SYSTEM_ERROR, throws an exception with different message
-  EXPECT_NONFATAL_FAILURE(EXPECT_SYSTEM_ERROR({  // NOLINT
-    a_++;
-    throw_system_error();
-  }, EDOM, (b_++, "other")),
-      "throws an exception with a different message");
+  EXPECT_NONFATAL_FAILURE(EXPECT_SYSTEM_ERROR(
+                              {  // NOLINT
+                                a_++;
+                                throw_system_error();
+                              },
+                              EDOM, (b_++, "other")),
+                          "throws an exception with a different message");
   EXPECT_EQ(3, a_);
   EXPECT_EQ(3, b_);
 
   // failed EXPECT_SYSTEM_ERROR, throws nothing
-  EXPECT_NONFATAL_FAILURE(
-      EXPECT_SYSTEM_ERROR(a_++, EDOM, (b_++, "test")), "throws nothing");
+  EXPECT_NONFATAL_FAILURE(EXPECT_SYSTEM_ERROR(a_++, EDOM, (b_++, "test")),
+                          "throws nothing");
   EXPECT_EQ(4, a_);
   EXPECT_EQ(4, b_);
 }
 
+#if FMT_USE_FCNTL
+// Tests that when EXPECT_WRITE fails, it evaluates its message argument
+// exactly once.
+TEST_F(SingleEvaluationTest, FailedEXPECT_WRITE) {
+  EXPECT_NONFATAL_FAILURE(EXPECT_WRITE(stdout, std::printf("test"), p_++),
+                          "01234");
+  EXPECT_EQ(s_ + 1, p_);
+}
+
 // Tests that assertion arguments are evaluated exactly once.
 TEST_F(SingleEvaluationTest, WriteTests) {
   // successful EXPECT_WRITE
-  EXPECT_WRITE(stdout, {  // NOLINT
-    a_++;
-    std::printf("test");
-  }, (b_++, "test"));
+  EXPECT_WRITE(
+      stdout,
+      {  // NOLINT
+        a_++;
+        std::printf("test");
+      },
+      (b_++, "test"));
   EXPECT_EQ(1, a_);
   EXPECT_EQ(1, b_);
 
   // failed EXPECT_WRITE
-  EXPECT_NONFATAL_FAILURE(EXPECT_WRITE(stdout, {  // NOLINT
-    a_++;
-    std::printf("test");
-  }, (b_++, "other")), "Actual: test");
+  EXPECT_NONFATAL_FAILURE(EXPECT_WRITE(
+                              stdout,
+                              {  // NOLINT
+                                a_++;
+                                std::printf("test");
+                              },
+                              (b_++, "other")),
+                          "Actual: test");
   EXPECT_EQ(2, a_);
   EXPECT_EQ(2, b_);
 }
 
+// Tests EXPECT_WRITE.
+TEST(ExpectTest, EXPECT_WRITE) {
+  EXPECT_WRITE(stdout, do_nothing(), "");
+  EXPECT_WRITE(stdout, std::printf("test"), "test");
+  EXPECT_WRITE(stderr, std::fprintf(stderr, "test"), "test");
+  EXPECT_NONFATAL_FAILURE(EXPECT_WRITE(stdout, std::printf("that"), "this"),
+                          "Expected: this\n"
+                          "  Actual: that");
+}
+
+TEST(StreamingAssertionsTest, EXPECT_WRITE) {
+  EXPECT_WRITE(stdout, std::printf("test"), "test") << "unexpected failure";
+  EXPECT_NONFATAL_FAILURE(EXPECT_WRITE(stdout, std::printf("test"), "other")
+                              << "expected failure",
+                          "expected failure");
+}
+#endif  // FMT_USE_FCNTL
+
 // Tests that the compiler will not complain about unreachable code in the
 // EXPECT_THROW_MSG macro.
 TEST(ExpectThrowTest, DoesNotGenerateUnreachableCodeWarning) {
@@ -179,8 +217,8 @@ TEST(ExpectThrowTest, DoesNotGenerateUnreachableCodeWarning) {
   EXPECT_THROW_MSG(throw runtime_error(""), runtime_error, "");
   EXPECT_NONFATAL_FAILURE(EXPECT_THROW_MSG(n++, runtime_error, ""), "");
   EXPECT_NONFATAL_FAILURE(EXPECT_THROW_MSG(throw 1, runtime_error, ""), "");
-  EXPECT_NONFATAL_FAILURE(EXPECT_THROW_MSG(
-      throw runtime_error("a"), runtime_error, "b"), "");
+  EXPECT_NONFATAL_FAILURE(
+      EXPECT_THROW_MSG(throw runtime_error("a"), runtime_error, "b"), "");
 }
 
 // Tests that the compiler will not complain about unreachable code in the
@@ -190,8 +228,9 @@ TEST(ExpectSystemErrorTest, DoesNotGenerateUnreachableCodeWarning) {
   EXPECT_SYSTEM_ERROR(throw fmt::system_error(EDOM, "test"), EDOM, "test");
   EXPECT_NONFATAL_FAILURE(EXPECT_SYSTEM_ERROR(n++, EDOM, ""), "");
   EXPECT_NONFATAL_FAILURE(EXPECT_SYSTEM_ERROR(throw 1, EDOM, ""), "");
-  EXPECT_NONFATAL_FAILURE(EXPECT_SYSTEM_ERROR(
-      throw fmt::system_error(EDOM, "aaa"), EDOM, "bbb"), "");
+  EXPECT_NONFATAL_FAILURE(
+      EXPECT_SYSTEM_ERROR(throw fmt::system_error(EDOM, "aaa"), EDOM, "bbb"),
+      "");
 }
 
 TEST(AssertionSyntaxTest, ExceptionAssertionBehavesLikeSingleStatement) {
@@ -263,23 +302,13 @@ TEST(ExpectTest, EXPECT_SYSTEM_ERROR) {
           format_system_error(EDOM, "test")));
 }
 
-// Tests EXPECT_WRITE.
-TEST(ExpectTest, EXPECT_WRITE) {
-  EXPECT_WRITE(stdout, do_nothing(), "");
-  EXPECT_WRITE(stdout, std::printf("test"), "test");
-  EXPECT_WRITE(stderr, std::fprintf(stderr, "test"), "test");
-  EXPECT_NONFATAL_FAILURE(
-      EXPECT_WRITE(stdout, std::printf("that"), "this"),
-      "Expected: this\n"
-      "  Actual: that");
-}
-
 TEST(StreamingAssertionsTest, EXPECT_THROW_MSG) {
   EXPECT_THROW_MSG(throw_exception(), std::exception, "test")
       << "unexpected failure";
   EXPECT_NONFATAL_FAILURE(
       EXPECT_THROW_MSG(throw_exception(), std::exception, "other")
-      << "expected failure", "expected failure");
+          << "expected failure",
+      "expected failure");
 }
 
 TEST(StreamingAssertionsTest, EXPECT_SYSTEM_ERROR) {
@@ -287,15 +316,8 @@ TEST(StreamingAssertionsTest, EXPECT_SYSTEM_ERROR) {
       << "unexpected failure";
   EXPECT_NONFATAL_FAILURE(
       EXPECT_SYSTEM_ERROR(throw_system_error(), EDOM, "other")
-      << "expected failure", "expected failure");
-}
-
-TEST(StreamingAssertionsTest, EXPECT_WRITE) {
-  EXPECT_WRITE(stdout, std::printf("test"), "test")
-      << "unexpected failure";
-  EXPECT_NONFATAL_FAILURE(
-      EXPECT_WRITE(stdout, std::printf("test"), "other")
-      << "expected failure", "expected failure");
+          << "expected failure",
+      "expected failure");
 }
 
 TEST(UtilTest, FormatSystemError) {
@@ -304,7 +326,7 @@ TEST(UtilTest, FormatSystemError) {
   EXPECT_EQ(to_string(out), format_system_error(EDOM, "test message"));
 }
 
-#if FMT_USE_FILE_DESCRIPTORS
+#if FMT_USE_FCNTL
 
 using fmt::buffered_file;
 using fmt::error_code;
@@ -340,10 +362,10 @@ TEST(OutputRedirectTest, FlushErrorInCtor) {
   // Put a character in a file buffer.
   EXPECT_EQ('x', fputc('x', f.get()));
   FMT_POSIX(close(write_fd));
-  scoped_ptr<OutputRedirect> redir{FMT_NULL};
-  EXPECT_SYSTEM_ERROR_NOASSERT(redir.reset(new OutputRedirect(f.get())),
-      EBADF, "cannot flush stream");
-  redir.reset(FMT_NULL);
+  std::unique_ptr<OutputRedirect> redir{nullptr};
+  EXPECT_SYSTEM_ERROR_NOASSERT(redir.reset(new OutputRedirect(f.get())), EBADF,
+                               "cannot flush stream");
+  redir.reset(nullptr);
   write_copy.dup2(write_fd);  // "undo" close or dtor will fail
 }
 
@@ -352,9 +374,10 @@ TEST(OutputRedirectTest, DupErrorInCtor) {
   int fd = (f.fileno)();
   file copy = file::dup(fd);
   FMT_POSIX(close(fd));
-  scoped_ptr<OutputRedirect> redir{FMT_NULL};
-  EXPECT_SYSTEM_ERROR_NOASSERT(redir.reset(new OutputRedirect(f.get())),
-      EBADF, fmt::format("cannot duplicate file descriptor {}", fd));
+  std::unique_ptr<OutputRedirect> redir{nullptr};
+  EXPECT_SYSTEM_ERROR_NOASSERT(
+      redir.reset(new OutputRedirect(f.get())), EBADF,
+      fmt::format("cannot duplicate file descriptor {}", fd));
   copy.dup2(fd);  // "undo" close or dtor will fail
 }
 
@@ -383,8 +406,8 @@ TEST(OutputRedirectTest, FlushErrorInRestoreAndRead) {
   // Put a character in a file buffer.
   EXPECT_EQ('x', fputc('x', f.get()));
   FMT_POSIX(close(write_fd));
-  EXPECT_SYSTEM_ERROR_NOASSERT(redir.restore_and_read(),
-      EBADF, "cannot flush stream");
+  EXPECT_SYSTEM_ERROR_NOASSERT(redir.restore_and_read(), EBADF,
+                               "cannot flush stream");
   write_copy.dup2(write_fd);  // "undo" close or dtor will fail
 }
 
@@ -394,18 +417,21 @@ TEST(OutputRedirectTest, ErrorInDtor) {
   int write_fd = write_end.descriptor();
   file write_copy = write_end.dup(write_fd);
   buffered_file f = write_end.fdopen("w");
-  scoped_ptr<OutputRedirect> redir(new OutputRedirect(f.get()));
+  std::unique_ptr<OutputRedirect> redir(new OutputRedirect(f.get()));
   // Put a character in a file buffer.
   EXPECT_EQ('x', fputc('x', f.get()));
-  EXPECT_WRITE(stderr, {
-      // The close function must be called inside EXPECT_WRITE, otherwise
-      // the system may recycle closed file descriptor when redirecting the
-      // output in EXPECT_STDERR and the second close will break output
-      // redirection.
-      FMT_POSIX(close(write_fd));
-      SUPPRESS_ASSERT(redir.reset(FMT_NULL));
-  }, format_system_error(EBADF, "cannot flush stream"));
-  write_copy.dup2(write_fd); // "undo" close or dtor of buffered_file will fail
+  EXPECT_WRITE(
+      stderr,
+      {
+        // The close function must be called inside EXPECT_WRITE,
+        // otherwise the system may recycle closed file descriptor when
+        // redirecting the output in EXPECT_STDERR and the second close
+        // will break output redirection.
+        FMT_POSIX(close(write_fd));
+        SUPPRESS_ASSERT(redir.reset(nullptr));
+      },
+      format_system_error(EBADF, "cannot flush stream"));
+  write_copy.dup2(write_fd);  // "undo" close or dtor of buffered_file will fail
 }
 
 #endif  // FMT_USE_FILE_DESCRIPTORS

test/gtest-extra.cc

@@ -7,30 +7,28 @@
 
 #include "gtest-extra.h"
 
-#if FMT_USE_FILE_DESCRIPTORS
+#if FMT_USE_FCNTL
 
 using fmt::file;
 
 void OutputRedirect::flush() {
-#if EOF != -1
-# error "FMT_RETRY assumes return value of -1 indicating failure"
-#endif
+#  if EOF != -1
+#    error "FMT_RETRY assumes return value of -1 indicating failure"
+#  endif
   int result = 0;
   FMT_RETRY(result, fflush(file_));
-  if (result != 0)
-    throw fmt::system_error(errno, "cannot flush stream");
+  if (result != 0) throw fmt::system_error(errno, "cannot flush stream");
 }
 
 void OutputRedirect::restore() {
-  if (original_.descriptor() == -1)
-    return;  // Already restored.
+  if (original_.descriptor() == -1) return;  // Already restored.
   flush();
   // Restore the original file.
   original_.dup2(FMT_POSIX(fileno(file_)));
   original_.close();
 }
 
-OutputRedirect::OutputRedirect(FILE *f) : file_(f) {
+OutputRedirect::OutputRedirect(FILE* f) : file_(f) {
   flush();
   int fd = FMT_POSIX(fileno(f));
   // Create a file object referring to the original file.
@@ -45,7 +43,7 @@ OutputRedirect::OutputRedirect(FILE *f) : file_(f) {
 OutputRedirect::~OutputRedirect() FMT_NOEXCEPT {
   try {
     restore();
-  } catch (const std::exception &e) {
+  } catch (const std::exception& e) {
     std::fputs(e.what(), stderr);
   }
 }
@@ -56,11 +54,10 @@ std::string OutputRedirect::restore_and_read() {
 
   // Read everything from the pipe.
   std::string content;
-  if (read_end_.descriptor() == -1)
-    return content;  // Already read.
+  if (read_end_.descriptor() == -1) return content;  // Already read.
   enum { BUFFER_SIZE = 4096 };
   char buffer[BUFFER_SIZE];
-  std::size_t count = 0;
+  size_t count = 0;
   do {
     count = read_end_.read(buffer, BUFFER_SIZE);
     content.append(buffer, count);
@@ -69,9 +66,9 @@ std::string OutputRedirect::restore_and_read() {
   return content;
 }
 
-std::string read(file &f, std::size_t count) {
+std::string read(file& f, size_t count) {
   std::string buffer(count, '\0');
-  std::size_t n = 0, offset = 0;
+  size_t n = 0, offset = 0;
   do {
     n = f.read(&buffer[offset], count - offset);
     // We can't read more than size_t bytes since count has type size_t.
@@ -81,7 +78,7 @@ std::string read(file &f, std::size_t count) {
   return buffer;
 }
 
-#endif  // FMT_USE_FILE_DESCRIPTORS
+#endif  // FMT_USE_FCNTL
 
 std::string format_system_error(int error_code, fmt::string_view message) {
   fmt::memory_buffer out;

test/gtest-extra.h

@@ -9,71 +9,61 @@
 #define FMT_GTEST_EXTRA_H_
 
 #include <string>
+
+#include "fmt/os.h"
 #include "gmock.h"
 
-#include "fmt/core.h"
-
-#ifndef FMT_USE_FILE_DESCRIPTORS
-# define FMT_USE_FILE_DESCRIPTORS 0
-#endif
-
-#if FMT_USE_FILE_DESCRIPTORS
-# include "fmt/posix.h"
-#endif
-
 #define FMT_TEST_THROW_(statement, expected_exception, expected_message, fail) \
-  GTEST_AMBIGUOUS_ELSE_BLOCKER_ \
-  if (::testing::AssertionResult gtest_ar = ::testing::AssertionSuccess()) { \
-    std::string gtest_expected_message = expected_message; \
-    bool gtest_caught_expected = false; \
-    try { \
-      GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement); \
-    } \
-    catch (expected_exception const& e) { \
-      if (gtest_expected_message != e.what()) { \
-        gtest_ar \
-          << #statement " throws an exception with a different message.\n" \
-          << "Expected: " << gtest_expected_message << "\n" \
-          << "  Actual: " << e.what(); \
-        goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__); \
-      } \
-      gtest_caught_expected = true; \
-    } \
-    catch (...) { \
-      gtest_ar << \
-          "Expected: " #statement " throws an exception of type " \
-          #expected_exception ".\n  Actual: it throws a different type."; \
-      goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__); \
-    } \
-    if (!gtest_caught_expected) { \
-      gtest_ar << \
-          "Expected: " #statement " throws an exception of type " \
-          #expected_exception ".\n  Actual: it throws nothing."; \
-      goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__); \
-    } \
-  } else \
-    GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__): \
-      fail(gtest_ar.failure_message())
+  GTEST_AMBIGUOUS_ELSE_BLOCKER_                                                \
+  if (::testing::AssertionResult gtest_ar = ::testing::AssertionSuccess()) {   \
+    std::string gtest_expected_message = expected_message;                     \
+    bool gtest_caught_expected = false;                                        \
+    try {                                                                      \
+      GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement);               \
+    } catch (expected_exception const& e) {                                    \
+      if (gtest_expected_message != e.what()) {                                \
+        gtest_ar << #statement                                                 \
+            " throws an exception with a different message.\n"                 \
+                 << "Expected: " << gtest_expected_message << "\n"             \
+                 << "  Actual: " << e.what();                                  \
+        goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__);            \
+      }                                                                        \
+      gtest_caught_expected = true;                                            \
+    } catch (...) {                                                            \
+      gtest_ar << "Expected: " #statement                                      \
+                  " throws an exception of type " #expected_exception          \
+                  ".\n  Actual: it throws a different type.";                  \
+      goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__);              \
+    }                                                                          \
+    if (!gtest_caught_expected) {                                              \
+      gtest_ar << "Expected: " #statement                                      \
+                  " throws an exception of type " #expected_exception          \
+                  ".\n  Actual: it throws nothing.";                           \
+      goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__);              \
+    }                                                                          \
+  } else                                                                       \
+    GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__)                      \
+        : fail(gtest_ar.failure_message())
 
 // Tests that the statement throws the expected exception and the exception's
 // what() method returns expected message.
 #define EXPECT_THROW_MSG(statement, expected_exception, expected_message) \
-  FMT_TEST_THROW_(statement, expected_exception, \
-      expected_message, GTEST_NONFATAL_FAILURE_)
+  FMT_TEST_THROW_(statement, expected_exception, expected_message,        \
+                  GTEST_NONFATAL_FAILURE_)
 
 std::string format_system_error(int error_code, fmt::string_view message);
 
 #define EXPECT_SYSTEM_ERROR(statement, error_code, message) \
-  EXPECT_THROW_MSG(statement, fmt::system_error, \
-      format_system_error(error_code, message))
+  EXPECT_THROW_MSG(statement, fmt::system_error,            \
+                   format_system_error(error_code, message))
 
-#if FMT_USE_FILE_DESCRIPTORS
+#if FMT_USE_FCNTL
 
 // Captures file output by redirecting it to a pipe.
 // The output it can handle is limited by the pipe capacity.
 class OutputRedirect {
  private:
-  FILE *file_;
+  FILE* file_;
   fmt::file original_;  // Original file passed to redirector.
   fmt::file read_end_;  // Read end of the pipe where the output is redirected.
 
@@ -83,7 +73,7 @@ class OutputRedirect {
   void restore();
 
  public:
-  explicit OutputRedirect(FILE *file);
+  explicit OutputRedirect(FILE* file);
   ~OutputRedirect() FMT_NOEXCEPT;
 
   // Restores the original file, reads output from the pipe into a string
@@ -91,29 +81,28 @@ class OutputRedirect {
   std::string restore_and_read();
 };
 
-#define FMT_TEST_WRITE_(statement, expected_output, file, fail) \
-  GTEST_AMBIGUOUS_ELSE_BLOCKER_ \
-  if (::testing::AssertionResult gtest_ar = ::testing::AssertionSuccess()) { \
-    std::string gtest_expected_output = expected_output; \
-    OutputRedirect gtest_redir(file); \
-    GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement); \
-    std::string gtest_output = gtest_redir.restore_and_read(); \
-    if (gtest_output != gtest_expected_output) { \
-      gtest_ar \
-        << #statement " produces different output.\n" \
-        << "Expected: " << gtest_expected_output << "\n" \
-        << "  Actual: " << gtest_output; \
-      goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__); \
-    } \
-  } else \
-    GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__): \
-      fail(gtest_ar.failure_message())
+#  define FMT_TEST_WRITE_(statement, expected_output, file, fail)              \
+    GTEST_AMBIGUOUS_ELSE_BLOCKER_                                              \
+    if (::testing::AssertionResult gtest_ar = ::testing::AssertionSuccess()) { \
+      std::string gtest_expected_output = expected_output;                     \
+      OutputRedirect gtest_redir(file);                                        \
+      GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement);               \
+      std::string gtest_output = gtest_redir.restore_and_read();               \
+      if (gtest_output != gtest_expected_output) {                             \
+        gtest_ar << #statement " produces different output.\n"                 \
+                 << "Expected: " << gtest_expected_output << "\n"              \
+                 << "  Actual: " << gtest_output;                              \
+        goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__);            \
+      }                                                                        \
+    } else                                                                     \
+      GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__)                    \
+          : fail(gtest_ar.failure_message())
 
 // Tests that the statement writes the expected output to file.
-#define EXPECT_WRITE(file, statement, expected_output) \
+#  define EXPECT_WRITE(file, statement, expected_output) \
     FMT_TEST_WRITE_(statement, expected_output, file, GTEST_NONFATAL_FAILURE_)
 
-#ifdef _MSC_VER
+#  ifdef _MSC_VER
 
 // Suppresses Windows assertions on invalid file descriptors, making
 // POSIX functions return proper error codes instead of crashing on Windows.
@@ -122,40 +111,52 @@ class SuppressAssert {
   _invalid_parameter_handler original_handler_;
   int original_report_mode_;
 
-  static void handle_invalid_parameter(const wchar_t *,
-      const wchar_t *, const wchar_t *, unsigned , uintptr_t) {}
+  static void handle_invalid_parameter(const wchar_t*, const wchar_t*,
+                                       const wchar_t*, unsigned, uintptr_t) {}
 
  public:
   SuppressAssert()
-  : original_handler_(_set_invalid_parameter_handler(handle_invalid_parameter)),
-    original_report_mode_(_CrtSetReportMode(_CRT_ASSERT, 0)) {
-  }
+      : original_handler_(
+            _set_invalid_parameter_handler(handle_invalid_parameter)),
+        original_report_mode_(_CrtSetReportMode(_CRT_ASSERT, 0)) {}
   ~SuppressAssert() {
     _set_invalid_parameter_handler(original_handler_);
     _CrtSetReportMode(_CRT_ASSERT, original_report_mode_);
   }
 };
 
-# define SUPPRESS_ASSERT(statement) { SuppressAssert sa; statement; }
-#else
-# define SUPPRESS_ASSERT(statement) statement
-#endif  // _MSC_VER
+#    define SUPPRESS_ASSERT(statement) \
+      {                                \
+        SuppressAssert sa;             \
+        statement;                     \
+      }
+#  else
+#    define SUPPRESS_ASSERT(statement) statement
+#  endif  // _MSC_VER
 
-#define EXPECT_SYSTEM_ERROR_NOASSERT(statement, error_code, message) \
-  EXPECT_SYSTEM_ERROR(SUPPRESS_ASSERT(statement), error_code, message)
+#  define EXPECT_SYSTEM_ERROR_NOASSERT(statement, error_code, message) \
+    EXPECT_SYSTEM_ERROR(SUPPRESS_ASSERT(statement), error_code, message)
 
 // Attempts to read count characters from a file.
-std::string read(fmt::file &f, std::size_t count);
+std::string read(fmt::file& f, size_t count);
 
-#define EXPECT_READ(file, expected_content) \
-  EXPECT_EQ(expected_content, read(file, std::strlen(expected_content)))
+#  define EXPECT_READ(file, expected_content) \
+    EXPECT_EQ(expected_content, \
+              read(file, fmt::string_view(expected_content).size()))
 
-#endif  // FMT_USE_FILE_DESCRIPTORS
+#else
+#  define EXPECT_WRITE(file, statement, expected_output) \
+    do {                                                 \
+      (void)(file);                                      \
+      (void)(statement);                                 \
+      (void)(expected_output);                           \
+      SUCCEED();                                         \
+    } while (false)
+#endif  // FMT_USE_FCNTL
 
-template <typename Mock>
-struct ScopedMock : testing::StrictMock<Mock> {
+template <typename Mock> struct ScopedMock : testing::StrictMock<Mock> {
   ScopedMock() { Mock::instance = this; }
-  ~ScopedMock() { Mock::instance = FMT_NULL; }
+  ~ScopedMock() { Mock::instance = nullptr; }
 };
 
 #endif  // FMT_GTEST_EXTRA_H_

test/locale-test.cc

@@ -6,29 +6,155 @@
 // For the license information refer to format.h.
 
 #include "fmt/locale.h"
+
+#include <complex>
+
 #include "gmock.h"
 
-template <typename Char>
-struct numpunct : std::numpunct<Char> {
+using fmt::detail::max_value;
+
+#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
+template <typename Char> struct numpunct : std::numpunct<Char> {
  protected:
+  Char do_decimal_point() const FMT_OVERRIDE { return '?'; }
+  std::string do_grouping() const FMT_OVERRIDE { return "\03"; }
   Char do_thousands_sep() const FMT_OVERRIDE { return '~'; }
 };
 
+template <typename Char> struct no_grouping : std::numpunct<Char> {
+ protected:
+  Char do_decimal_point() const FMT_OVERRIDE { return '.'; }
+  std::string do_grouping() const FMT_OVERRIDE { return ""; }
+  Char do_thousands_sep() const FMT_OVERRIDE { return ','; }
+};
+
+template <typename Char> struct special_grouping : std::numpunct<Char> {
+ protected:
+  Char do_decimal_point() const FMT_OVERRIDE { return '.'; }
+  std::string do_grouping() const FMT_OVERRIDE { return "\03\02"; }
+  Char do_thousands_sep() const FMT_OVERRIDE { return ','; }
+};
+
+template <typename Char> struct small_grouping : std::numpunct<Char> {
+ protected:
+  Char do_decimal_point() const FMT_OVERRIDE { return '.'; }
+  std::string do_grouping() const FMT_OVERRIDE { return "\01"; }
+  Char do_thousands_sep() const FMT_OVERRIDE { return ','; }
+};
+
+TEST(LocaleTest, DoubleDecimalPoint) {
+  std::locale loc(std::locale(), new numpunct<char>());
+  EXPECT_EQ("1?23", fmt::format(loc, "{:L}", 1.23));
+}
+
 TEST(LocaleTest, Format) {
   std::locale loc(std::locale(), new numpunct<char>());
-  EXPECT_EQ("1,234,567", fmt::format(std::locale(), "{:n}", 1234567));
-  EXPECT_EQ("1~234~567", fmt::format(loc, "{:n}", 1234567));
+  EXPECT_EQ("1234567", fmt::format(std::locale(), "{:L}", 1234567));
+  EXPECT_EQ("1~234~567", fmt::format(loc, "{:L}", 1234567));
+  EXPECT_EQ("-1~234~567", fmt::format(loc, "{:L}", -1234567));
+  EXPECT_EQ("-256", fmt::format(loc, "{:L}", -256));
   fmt::format_arg_store<fmt::format_context, int> as{1234567};
-  EXPECT_EQ("1~234~567", fmt::vformat(loc, "{:n}", fmt::format_args(as)));
+  EXPECT_EQ("1~234~567", fmt::vformat(loc, "{:L}", fmt::format_args(as)));
   std::string s;
-  fmt::format_to(std::back_inserter(s), loc, "{:n}", 1234567);
+  fmt::format_to(std::back_inserter(s), loc, "{:L}", 1234567);
   EXPECT_EQ("1~234~567", s);
+
+  std::locale no_grouping_loc(std::locale(), new no_grouping<char>());
+  EXPECT_EQ("1234567", fmt::format(no_grouping_loc, "{:L}", 1234567));
+
+  std::locale special_grouping_loc(std::locale(), new special_grouping<char>());
+  EXPECT_EQ("1,23,45,678", fmt::format(special_grouping_loc, "{:L}", 12345678));
+  EXPECT_EQ("12,345", fmt::format(special_grouping_loc, "{:L}", 12345));
+
+  std::locale small_grouping_loc(std::locale(), new small_grouping<char>());
+  EXPECT_EQ("4,2,9,4,9,6,7,2,9,5",
+            fmt::format(small_grouping_loc, "{:L}", max_value<uint32_t>()));
+}
+
+TEST(LocaleTest, FormatDetaultAlign) {
+  std::locale special_grouping_loc(std::locale(), new special_grouping<char>());
+  EXPECT_EQ("  12,345", fmt::format(special_grouping_loc, "{:8L}", 12345));
 }
 
 TEST(LocaleTest, WFormat) {
   std::locale loc(std::locale(), new numpunct<wchar_t>());
-  EXPECT_EQ(L"1,234,567", fmt::format(std::locale(), L"{:n}", 1234567));
-  EXPECT_EQ(L"1~234~567", fmt::format(loc, L"{:n}", 1234567));
+  EXPECT_EQ(L"1234567", fmt::format(std::locale(), L"{:L}", 1234567));
+  EXPECT_EQ(L"1~234~567", fmt::format(loc, L"{:L}", 1234567));
   fmt::format_arg_store<fmt::wformat_context, int> as{1234567};
-  EXPECT_EQ(L"1~234~567", fmt::vformat(loc, L"{:n}", fmt::wformat_args(as)));
+  EXPECT_EQ(L"1~234~567", fmt::vformat(loc, L"{:L}", fmt::wformat_args(as)));
+  EXPECT_EQ(L"1234567", fmt::format(std::locale("C"), L"{:L}", 1234567));
+
+  std::locale no_grouping_loc(std::locale(), new no_grouping<wchar_t>());
+  EXPECT_EQ(L"1234567", fmt::format(no_grouping_loc, L"{:L}", 1234567));
+
+  std::locale special_grouping_loc(std::locale(),
+                                   new special_grouping<wchar_t>());
+  EXPECT_EQ(L"1,23,45,678",
+            fmt::format(special_grouping_loc, L"{:L}", 12345678));
+
+  std::locale small_grouping_loc(std::locale(), new small_grouping<wchar_t>());
+  EXPECT_EQ(L"4,2,9,4,9,6,7,2,9,5",
+            fmt::format(small_grouping_loc, L"{:L}", max_value<uint32_t>()));
 }
+
+TEST(LocaleTest, DoubleFormatter) {
+  auto loc = std::locale(std::locale(), new special_grouping<char>());
+  auto f = fmt::formatter<int>();
+  auto parse_ctx = fmt::format_parse_context("L");
+  f.parse(parse_ctx);
+  char buf[10] = {};
+  fmt::basic_format_context<char*, char> format_ctx(
+      buf, {}, fmt::detail::locale_ref(loc));
+  *f.format(12345, format_ctx) = 0;
+  EXPECT_STREQ("12,345", buf);
+}
+
+FMT_BEGIN_NAMESPACE
+template <class charT> struct formatter<std::complex<double>, charT> {
+ private:
+  detail::dynamic_format_specs<char> specs_;
+
+ public:
+  typename basic_format_parse_context<charT>::iterator parse(
+      basic_format_parse_context<charT>& ctx) {
+    using handler_type =
+        detail::dynamic_specs_handler<basic_format_parse_context<charT>>;
+    detail::specs_checker<handler_type> handler(handler_type(specs_, ctx),
+                                                detail::type::string_type);
+    auto it = parse_format_specs(ctx.begin(), ctx.end(), handler);
+    detail::parse_float_type_spec(specs_, ctx.error_handler());
+    return it;
+  }
+
+  template <class FormatContext>
+  typename FormatContext::iterator format(const std::complex<double>& c,
+                                          FormatContext& ctx) {
+    detail::handle_dynamic_spec<detail::precision_checker>(
+        specs_.precision, specs_.precision_ref, ctx);
+    auto format_specs = std::string();
+    if (specs_.precision > 0)
+      format_specs = fmt::format(".{}", specs_.precision);
+    if (specs_.type)
+      format_specs += specs_.type;
+    auto real = fmt::format(ctx.locale().template get<std::locale>(),
+                            "{:" + format_specs + "}", c.real());
+    auto imag = fmt::format(ctx.locale().template get<std::locale>(),
+                            "{:" + format_specs + "}", c.imag());
+    auto fill_align_width = std::string();
+    if (specs_.width > 0)
+      fill_align_width = fmt::format(">{}", specs_.width);
+    return format_to(
+        ctx.out(), "{:" + fill_align_width + "}",
+        fmt::format(c.real() != 0 ? "({0}+{1}i)" : "{1}i", real, imag));
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(FormatTest, Complex) {
+  std::string s = fmt::format("{}", std::complex<double>(1, 2));
+  EXPECT_EQ(s, "(1+2i)");
+  EXPECT_EQ(fmt::format("{:.2f}", std::complex<double>(1, 2)), "(1.00+2.00i)");
+  EXPECT_EQ(fmt::format("{:8}", std::complex<double>(1, 2)), "  (1+2i)");
+}
+
+#endif  // FMT_STATIC_THOUSANDS_SEPARATOR

test/mock-allocator.h

@@ -8,55 +8,53 @@
 #ifndef FMT_MOCK_ALLOCATOR_H_
 #define FMT_MOCK_ALLOCATOR_H_
 
-#include "gmock.h"
 #include "fmt/format.h"
+#include "gmock.h"
 
-template <typename T>
-class mock_allocator {
+template <typename T> class mock_allocator {
  public:
   mock_allocator() {}
-  mock_allocator(const mock_allocator &) {}
+  mock_allocator(const mock_allocator&) {}
   typedef T value_type;
-  MOCK_METHOD1_T(allocate, T* (std::size_t n));
-  MOCK_METHOD2_T(deallocate, void (T* p, std::size_t n));
+  MOCK_METHOD1_T(allocate, T*(size_t n));
+  MOCK_METHOD2_T(deallocate, void(T* p, size_t n));
 };
 
-template <typename Allocator>
-class allocator_ref {
+template <typename Allocator> class allocator_ref {
  private:
-  Allocator *alloc_;
+  Allocator* alloc_;
 
-  void move(allocator_ref &other) {
+  void move(allocator_ref& other) {
     alloc_ = other.alloc_;
-    other.alloc_ = FMT_NULL;
+    other.alloc_ = nullptr;
   }
 
  public:
   typedef typename Allocator::value_type value_type;
 
-  explicit allocator_ref(Allocator *alloc = FMT_NULL) : alloc_(alloc) {}
+  explicit allocator_ref(Allocator* alloc = nullptr) : alloc_(alloc) {}
 
-  allocator_ref(const allocator_ref &other) : alloc_(other.alloc_) {}
-  allocator_ref(allocator_ref &&other) { move(other); }
+  allocator_ref(const allocator_ref& other) : alloc_(other.alloc_) {}
+  allocator_ref(allocator_ref&& other) { move(other); }
 
-  allocator_ref& operator=(allocator_ref &&other) {
+  allocator_ref& operator=(allocator_ref&& other) {
     assert(this != &other);
     move(other);
     return *this;
   }
 
-  allocator_ref& operator=(const allocator_ref &other) {
+  allocator_ref& operator=(const allocator_ref& other) {
     alloc_ = other.alloc_;
     return *this;
   }
 
  public:
-  Allocator *get() const { return alloc_; }
+  Allocator* get() const { return alloc_; }
 
-  value_type* allocate(std::size_t n) {
-    return fmt::internal::allocate(*alloc_, n);
+  value_type* allocate(size_t n) {
+    return std::allocator_traits<Allocator>::allocate(*alloc_, n);
   }
-  void deallocate(value_type* p, std::size_t n) { alloc_->deallocate(p, n); }
+  void deallocate(value_type* p, size_t n) { alloc_->deallocate(p, n); }
 };
 
 #endif  // FMT_MOCK_ALLOCATOR_H_

test/os-test.cc

@@ -0,0 +1,532 @@
+// Formatting library for C++ - tests of the OS-specific functionality
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include "fmt/os.h"
+
+#include <cstdlib>  // std::exit
+#include <cstring>
+#include <memory>
+
+#include "gtest-extra.h"
+#include "util.h"
+
+#ifdef fileno
+#  undef fileno
+#endif
+
+using fmt::buffered_file;
+using fmt::error_code;
+
+#ifdef _WIN32
+
+#  include <windows.h>
+
+TEST(UtilTest, UTF16ToUTF8) {
+  std::string s = "ёжик";
+  fmt::detail::utf16_to_utf8 u(L"\x0451\x0436\x0438\x043A");
+  EXPECT_EQ(s, u.str());
+  EXPECT_EQ(s.size(), u.size());
+}
+
+TEST(UtilTest, UTF16ToUTF8EmptyString) {
+  std::string s = "";
+  fmt::detail::utf16_to_utf8 u(L"");
+  EXPECT_EQ(s, u.str());
+  EXPECT_EQ(s.size(), u.size());
+}
+
+template <typename Converter, typename Char>
+void check_utf_conversion_error(
+    const char* message,
+    fmt::basic_string_view<Char> str = fmt::basic_string_view<Char>(0, 1)) {
+  fmt::memory_buffer out;
+  fmt::detail::format_windows_error(out, ERROR_INVALID_PARAMETER, message);
+  fmt::system_error error(0, "");
+  try {
+    (Converter)(str);
+  } catch (const fmt::system_error& e) {
+    error = e;
+  }
+  EXPECT_EQ(ERROR_INVALID_PARAMETER, error.error_code());
+  EXPECT_EQ(fmt::to_string(out), error.what());
+}
+
+TEST(UtilTest, UTF16ToUTF8Error) {
+  check_utf_conversion_error<fmt::detail::utf16_to_utf8, wchar_t>(
+      "cannot convert string from UTF-16 to UTF-8");
+}
+
+TEST(UtilTest, UTF16ToUTF8Convert) {
+  fmt::detail::utf16_to_utf8 u;
+  EXPECT_EQ(ERROR_INVALID_PARAMETER, u.convert(fmt::wstring_view(0, 1)));
+  EXPECT_EQ(ERROR_INVALID_PARAMETER,
+            u.convert(fmt::wstring_view(L"foo", INT_MAX + 1u)));
+}
+
+TEST(UtilTest, FormatWindowsError) {
+  LPWSTR message = 0;
+  FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM |
+                     FORMAT_MESSAGE_IGNORE_INSERTS,
+                 0, ERROR_FILE_EXISTS,
+                 MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+                 reinterpret_cast<LPWSTR>(&message), 0, 0);
+  fmt::detail::utf16_to_utf8 utf8_message(message);
+  LocalFree(message);
+  fmt::memory_buffer actual_message;
+  fmt::detail::format_windows_error(actual_message, ERROR_FILE_EXISTS, "test");
+  EXPECT_EQ(fmt::format("test: {}", utf8_message.str()),
+            fmt::to_string(actual_message));
+  actual_message.resize(0);
+  auto max_size = fmt::detail::max_value<size_t>() / 2;
+  fmt::detail::format_windows_error(actual_message, ERROR_FILE_EXISTS,
+                                    fmt::string_view(nullptr, max_size));
+  EXPECT_EQ(fmt::format("error {}", ERROR_FILE_EXISTS),
+            fmt::to_string(actual_message));
+}
+
+TEST(UtilTest, FormatLongWindowsError) {
+  LPWSTR message = 0;
+  // this error code is not available on all Windows platforms and
+  // Windows SDKs, so do not fail the test if the error string cannot
+  // be retrieved.
+  const int provisioning_not_allowed =
+      0x80284013L /*TBS_E_PROVISIONING_NOT_ALLOWED*/;
+  if (FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+                         FORMAT_MESSAGE_FROM_SYSTEM |
+                         FORMAT_MESSAGE_IGNORE_INSERTS,
+                     0, static_cast<DWORD>(provisioning_not_allowed),
+                     MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+                     reinterpret_cast<LPWSTR>(&message), 0, 0) == 0) {
+    return;
+  }
+  fmt::detail::utf16_to_utf8 utf8_message(message);
+  LocalFree(message);
+  fmt::memory_buffer actual_message;
+  fmt::detail::format_windows_error(actual_message, provisioning_not_allowed,
+                                    "test");
+  EXPECT_EQ(fmt::format("test: {}", utf8_message.str()),
+            fmt::to_string(actual_message));
+}
+
+TEST(UtilTest, WindowsError) {
+  fmt::system_error error(0, "");
+  try {
+    throw fmt::windows_error(ERROR_FILE_EXISTS, "test {}", "error");
+  } catch (const fmt::system_error& e) {
+    error = e;
+  }
+  fmt::memory_buffer message;
+  fmt::detail::format_windows_error(message, ERROR_FILE_EXISTS, "test error");
+  EXPECT_EQ(to_string(message), error.what());
+  EXPECT_EQ(ERROR_FILE_EXISTS, error.error_code());
+}
+
+TEST(UtilTest, ReportWindowsError) {
+  fmt::memory_buffer out;
+  fmt::detail::format_windows_error(out, ERROR_FILE_EXISTS, "test error");
+  out.push_back('\n');
+  EXPECT_WRITE(stderr,
+               fmt::report_windows_error(ERROR_FILE_EXISTS, "test error"),
+               fmt::to_string(out));
+}
+
+#endif  // _WIN32
+
+#if FMT_USE_FCNTL
+
+using fmt::file;
+
+// Checks if the file is open by reading one character from it.
+static bool isopen(int fd) {
+  char buffer;
+  return FMT_POSIX(read(fd, &buffer, 1)) == 1;
+}
+
+static bool isclosed(int fd) {
+  char buffer;
+  std::streamsize result = 0;
+  SUPPRESS_ASSERT(result = FMT_POSIX(read(fd, &buffer, 1)));
+  return result == -1 && errno == EBADF;
+}
+
+// Opens a file for reading.
+static file open_file() {
+  file read_end, write_end;
+  file::pipe(read_end, write_end);
+  write_end.write(FILE_CONTENT, std::strlen(FILE_CONTENT));
+  write_end.close();
+  return read_end;
+}
+
+// Attempts to write a string to a file.
+static void write(file& f, fmt::string_view s) {
+  size_t num_chars_left = s.size();
+  const char* ptr = s.data();
+  do {
+    size_t count = f.write(ptr, num_chars_left);
+    ptr += count;
+    // We can't write more than size_t bytes since num_chars_left
+    // has type size_t.
+    num_chars_left -= count;
+  } while (num_chars_left != 0);
+}
+
+TEST(BufferedFileTest, DefaultCtor) {
+  buffered_file f;
+  EXPECT_TRUE(f.get() == nullptr);
+}
+
+TEST(BufferedFileTest, MoveCtor) {
+  buffered_file bf = open_buffered_file();
+  FILE* fp = bf.get();
+  EXPECT_TRUE(fp != nullptr);
+  buffered_file bf2(std::move(bf));
+  EXPECT_EQ(fp, bf2.get());
+  EXPECT_TRUE(bf.get() == nullptr);
+}
+
+TEST(BufferedFileTest, MoveAssignment) {
+  buffered_file bf = open_buffered_file();
+  FILE* fp = bf.get();
+  EXPECT_TRUE(fp != nullptr);
+  buffered_file bf2;
+  bf2 = std::move(bf);
+  EXPECT_EQ(fp, bf2.get());
+  EXPECT_TRUE(bf.get() == nullptr);
+}
+
+TEST(BufferedFileTest, MoveAssignmentClosesFile) {
+  buffered_file bf = open_buffered_file();
+  buffered_file bf2 = open_buffered_file();
+  int old_fd = bf2.fileno();
+  bf2 = std::move(bf);
+  EXPECT_TRUE(isclosed(old_fd));
+}
+
+TEST(BufferedFileTest, MoveFromTemporaryInCtor) {
+  FILE* fp = nullptr;
+  buffered_file f(open_buffered_file(&fp));
+  EXPECT_EQ(fp, f.get());
+}
+
+TEST(BufferedFileTest, MoveFromTemporaryInAssignment) {
+  FILE* fp = nullptr;
+  buffered_file f;
+  f = open_buffered_file(&fp);
+  EXPECT_EQ(fp, f.get());
+}
+
+TEST(BufferedFileTest, MoveFromTemporaryInAssignmentClosesFile) {
+  buffered_file f = open_buffered_file();
+  int old_fd = f.fileno();
+  f = open_buffered_file();
+  EXPECT_TRUE(isclosed(old_fd));
+}
+
+TEST(BufferedFileTest, CloseFileInDtor) {
+  int fd = 0;
+  {
+    buffered_file f = open_buffered_file();
+    fd = f.fileno();
+  }
+  EXPECT_TRUE(isclosed(fd));
+}
+
+TEST(BufferedFileTest, CloseErrorInDtor) {
+  std::unique_ptr<buffered_file> f(new buffered_file(open_buffered_file()));
+  EXPECT_WRITE(
+      stderr,
+      {
+        // The close function must be called inside EXPECT_WRITE,
+        // otherwise the system may recycle closed file descriptor when
+        // redirecting the output in EXPECT_STDERR and the second close
+        // will break output redirection.
+        FMT_POSIX(close(f->fileno()));
+        SUPPRESS_ASSERT(f.reset(nullptr));
+      },
+      format_system_error(EBADF, "cannot close file") + "\n");
+}
+
+TEST(BufferedFileTest, Close) {
+  buffered_file f = open_buffered_file();
+  int fd = f.fileno();
+  f.close();
+  EXPECT_TRUE(f.get() == nullptr);
+  EXPECT_TRUE(isclosed(fd));
+}
+
+TEST(BufferedFileTest, CloseError) {
+  buffered_file f = open_buffered_file();
+  FMT_POSIX(close(f.fileno()));
+  EXPECT_SYSTEM_ERROR_NOASSERT(f.close(), EBADF, "cannot close file");
+  EXPECT_TRUE(f.get() == nullptr);
+}
+
+TEST(BufferedFileTest, Fileno) {
+  buffered_file f;
+#  ifndef __COVERITY__
+  // fileno on a null FILE pointer either crashes or returns an error.
+  // Disable Coverity because this is intentional.
+  EXPECT_DEATH_IF_SUPPORTED(
+      {
+        try {
+          f.fileno();
+        } catch (const fmt::system_error&) {
+          std::exit(1);
+        }
+      },
+      "");
+#  endif
+  f = open_buffered_file();
+  EXPECT_TRUE(f.fileno() != -1);
+  file copy = file::dup(f.fileno());
+  EXPECT_READ(copy, FILE_CONTENT);
+}
+
+TEST(OStreamTest, Move) {
+  fmt::ostream out = fmt::output_file("test-file");
+  fmt::ostream moved(std::move(out));
+  moved.print("hello");
+}
+
+TEST(OStreamTest, Print) {
+  fmt::ostream out = fmt::output_file("test-file");
+  out.print("The answer is {}.\n", 42);
+  out.close();
+  file in("test-file", file::RDONLY);
+  EXPECT_READ(in, "The answer is 42.\n");
+}
+
+TEST(OStreamTest, BufferBoundary) {
+  auto str = std::string(4096, 'x');
+  fmt::ostream out = fmt::output_file("test-file");
+  out.print("{}", str);
+  out.print("{}", str);
+  out.close();
+  file in("test-file", file::RDONLY);
+  EXPECT_READ(in, str + str);
+}
+
+TEST(OStreamTest, BufferSize) {
+  fmt::ostream out = fmt::output_file("test-file", fmt::buffer_size=1);
+  out.print("{}", "foo");
+  out.close();
+  file in("test-file", file::RDONLY);
+  EXPECT_READ(in, "foo");
+}
+
+TEST(FileTest, DefaultCtor) {
+  file f;
+  EXPECT_EQ(-1, f.descriptor());
+}
+
+TEST(FileTest, OpenBufferedFileInCtor) {
+  FILE* fp = safe_fopen("test-file", "w");
+  std::fputs(FILE_CONTENT, fp);
+  std::fclose(fp);
+  file f("test-file", file::RDONLY);
+  ASSERT_TRUE(isopen(f.descriptor()));
+}
+
+TEST(FileTest, OpenBufferedFileError) {
+  EXPECT_SYSTEM_ERROR(file("nonexistent", file::RDONLY), ENOENT,
+                      "cannot open file nonexistent");
+}
+
+TEST(FileTest, MoveCtor) {
+  file f = open_file();
+  int fd = f.descriptor();
+  EXPECT_NE(-1, fd);
+  file f2(std::move(f));
+  EXPECT_EQ(fd, f2.descriptor());
+  EXPECT_EQ(-1, f.descriptor());
+}
+
+TEST(FileTest, MoveAssignment) {
+  file f = open_file();
+  int fd = f.descriptor();
+  EXPECT_NE(-1, fd);
+  file f2;
+  f2 = std::move(f);
+  EXPECT_EQ(fd, f2.descriptor());
+  EXPECT_EQ(-1, f.descriptor());
+}
+
+TEST(FileTest, MoveAssignmentClosesFile) {
+  file f = open_file();
+  file f2 = open_file();
+  int old_fd = f2.descriptor();
+  f2 = std::move(f);
+  EXPECT_TRUE(isclosed(old_fd));
+}
+
+static file OpenBufferedFile(int& fd) {
+  file f = open_file();
+  fd = f.descriptor();
+  return f;
+}
+
+TEST(FileTest, MoveFromTemporaryInCtor) {
+  int fd = 0xdead;
+  file f(OpenBufferedFile(fd));
+  EXPECT_EQ(fd, f.descriptor());
+}
+
+TEST(FileTest, MoveFromTemporaryInAssignment) {
+  int fd = 0xdead;
+  file f;
+  f = OpenBufferedFile(fd);
+  EXPECT_EQ(fd, f.descriptor());
+}
+
+TEST(FileTest, MoveFromTemporaryInAssignmentClosesFile) {
+  int fd = 0xdead;
+  file f = open_file();
+  int old_fd = f.descriptor();
+  f = OpenBufferedFile(fd);
+  EXPECT_TRUE(isclosed(old_fd));
+}
+
+TEST(FileTest, CloseFileInDtor) {
+  int fd = 0;
+  {
+    file f = open_file();
+    fd = f.descriptor();
+  }
+  EXPECT_TRUE(isclosed(fd));
+}
+
+TEST(FileTest, CloseErrorInDtor) {
+  std::unique_ptr<file> f(new file(open_file()));
+  EXPECT_WRITE(
+      stderr,
+      {
+        // The close function must be called inside EXPECT_WRITE,
+        // otherwise the system may recycle closed file descriptor when
+        // redirecting the output in EXPECT_STDERR and the second close
+        // will break output redirection.
+        FMT_POSIX(close(f->descriptor()));
+        SUPPRESS_ASSERT(f.reset(nullptr));
+      },
+      format_system_error(EBADF, "cannot close file") + "\n");
+}
+
+TEST(FileTest, Close) {
+  file f = open_file();
+  int fd = f.descriptor();
+  f.close();
+  EXPECT_EQ(-1, f.descriptor());
+  EXPECT_TRUE(isclosed(fd));
+}
+
+TEST(FileTest, CloseError) {
+  file f = open_file();
+  FMT_POSIX(close(f.descriptor()));
+  EXPECT_SYSTEM_ERROR_NOASSERT(f.close(), EBADF, "cannot close file");
+  EXPECT_EQ(-1, f.descriptor());
+}
+
+TEST(FileTest, Read) {
+  file f = open_file();
+  EXPECT_READ(f, FILE_CONTENT);
+}
+
+TEST(FileTest, ReadError) {
+  file f("test-file", file::WRONLY);
+  char buf;
+  // We intentionally read from a file opened in the write-only mode to
+  // cause error.
+  EXPECT_SYSTEM_ERROR(f.read(&buf, 1), EBADF, "cannot read from file");
+}
+
+TEST(FileTest, Write) {
+  file read_end, write_end;
+  file::pipe(read_end, write_end);
+  write(write_end, "test");
+  write_end.close();
+  EXPECT_READ(read_end, "test");
+}
+
+TEST(FileTest, WriteError) {
+  file f("test-file", file::RDONLY);
+  // We intentionally write to a file opened in the read-only mode to
+  // cause error.
+  EXPECT_SYSTEM_ERROR(f.write(" ", 1), EBADF, "cannot write to file");
+}
+
+TEST(FileTest, Dup) {
+  file f = open_file();
+  file copy = file::dup(f.descriptor());
+  EXPECT_NE(f.descriptor(), copy.descriptor());
+  EXPECT_EQ(FILE_CONTENT, read(copy, std::strlen(FILE_CONTENT)));
+}
+
+#  ifndef __COVERITY__
+TEST(FileTest, DupError) {
+  int value = -1;
+  EXPECT_SYSTEM_ERROR_NOASSERT(file::dup(value), EBADF,
+                               "cannot duplicate file descriptor -1");
+}
+#  endif
+
+TEST(FileTest, Dup2) {
+  file f = open_file();
+  file copy = open_file();
+  f.dup2(copy.descriptor());
+  EXPECT_NE(f.descriptor(), copy.descriptor());
+  EXPECT_READ(copy, FILE_CONTENT);
+}
+
+TEST(FileTest, Dup2Error) {
+  file f = open_file();
+  EXPECT_SYSTEM_ERROR_NOASSERT(
+      f.dup2(-1), EBADF,
+      fmt::format("cannot duplicate file descriptor {} to -1", f.descriptor()));
+}
+
+TEST(FileTest, Dup2NoExcept) {
+  file f = open_file();
+  file copy = open_file();
+  error_code ec;
+  f.dup2(copy.descriptor(), ec);
+  EXPECT_EQ(ec.get(), 0);
+  EXPECT_NE(f.descriptor(), copy.descriptor());
+  EXPECT_READ(copy, FILE_CONTENT);
+}
+
+TEST(FileTest, Dup2NoExceptError) {
+  file f = open_file();
+  error_code ec;
+  SUPPRESS_ASSERT(f.dup2(-1, ec));
+  EXPECT_EQ(EBADF, ec.get());
+}
+
+TEST(FileTest, Pipe) {
+  file read_end, write_end;
+  file::pipe(read_end, write_end);
+  EXPECT_NE(-1, read_end.descriptor());
+  EXPECT_NE(-1, write_end.descriptor());
+  write(write_end, "test");
+  EXPECT_READ(read_end, "test");
+}
+
+TEST(FileTest, Fdopen) {
+  file read_end, write_end;
+  file::pipe(read_end, write_end);
+  int read_fd = read_end.descriptor();
+  EXPECT_EQ(read_fd, FMT_POSIX(fileno(read_end.fdopen("r").get())));
+}
+
+#  ifdef FMT_LOCALE
+TEST(LocaleTest, Strtod) {
+  fmt::locale loc;
+  const char *start = "4.2", *ptr = start;
+  EXPECT_EQ(4.2, loc.strtod(ptr));
+  EXPECT_EQ(start + 3, ptr);
+}
+#  endif
+#endif  // FMT_USE_FCNTL

test/ostream-test.cc

@@ -6,9 +6,24 @@
 // For the license information refer to format.h.
 
 #define FMT_STRING_ALIAS 1
-#include "fmt/ostream.h"
+#include "fmt/format.h"
+
+struct test {};
+
+// Test that there is no issues with specializations when fmt/ostream.h is
+// included after fmt/format.h.
+namespace fmt {
+template <> struct formatter<test> : formatter<int> {
+  template <typename FormatContext>
+  typename FormatContext::iterator format(const test&, FormatContext& ctx) {
+    return formatter<int>::format(42, ctx);
+  }
+};
+}  // namespace fmt
 
 #include <sstream>
+
+#include "fmt/ostream.h"
 #include "gmock.h"
 #include "gtest-extra.h"
 #include "util.h"
@@ -16,51 +31,57 @@
 using fmt::format;
 using fmt::format_error;
 
-static std::ostream &operator<<(std::ostream &os, const Date &d) {
+static std::ostream& operator<<(std::ostream& os, const Date& d) {
   os << d.year() << '-' << d.month() << '-' << d.day();
   return os;
 }
 
-static std::wostream &operator<<(std::wostream &os, const Date &d) {
+static std::wostream& operator<<(std::wostream& os, const Date& d) {
   os << d.year() << L'-' << d.month() << L'-' << d.day();
   return os;
 }
 
-enum TestEnum {};
-static std::ostream &operator<<(std::ostream &os, TestEnum) {
-  return os << "TestEnum";
+// Make sure that overloaded comma operators do no harm to is_streamable.
+struct type_with_comma_op {};
+template <typename T> void operator,(type_with_comma_op, const T&);
+template <typename T> type_with_comma_op operator<<(T&, const Date&);
+
+enum streamable_enum {};
+static std::ostream& operator<<(std::ostream& os, streamable_enum) {
+  return os << "streamable_enum";
 }
 
-static std::wostream &operator<<(std::wostream &os, TestEnum) {
-  return os << L"TestEnum";
+static std::wostream& operator<<(std::wostream& os, streamable_enum) {
+  return os << L"streamable_enum";
 }
 
-enum TestEnum2 {A};
+enum unstreamable_enum {};
 
 TEST(OStreamTest, Enum) {
-  EXPECT_FALSE((fmt::convert_to_int<TestEnum, char>::value));
-  EXPECT_EQ("TestEnum", fmt::format("{}", TestEnum()));
-  EXPECT_EQ("0", fmt::format("{}", A));
-  EXPECT_FALSE((fmt::convert_to_int<TestEnum, wchar_t>::value));
-  EXPECT_EQ(L"TestEnum", fmt::format(L"{}", TestEnum()));
-  EXPECT_EQ(L"0", fmt::format(L"{}", A));
+  EXPECT_EQ("streamable_enum", fmt::format("{}", streamable_enum()));
+  EXPECT_EQ("0", fmt::format("{}", unstreamable_enum()));
+  EXPECT_EQ(L"streamable_enum", fmt::format(L"{}", streamable_enum()));
+  EXPECT_EQ(L"0", fmt::format(L"{}", unstreamable_enum()));
 }
 
-typedef fmt::back_insert_range<fmt::internal::buffer> range;
-
-struct test_arg_formatter: fmt::arg_formatter<range> {
-  test_arg_formatter(fmt::format_context &ctx, fmt::format_specs &s)
-    : fmt::arg_formatter<range>(ctx, &s) {}
+struct test_arg_formatter
+    : fmt::detail::arg_formatter<fmt::format_context::iterator, char> {
+  fmt::format_parse_context parse_ctx;
+  test_arg_formatter(fmt::format_context& ctx, fmt::format_specs& s)
+      : fmt::detail::arg_formatter<fmt::format_context::iterator, char>(
+            ctx, &parse_ctx, &s),
+        parse_ctx("") {}
 };
 
 TEST(OStreamTest, CustomArg) {
   fmt::memory_buffer buffer;
-  fmt::internal::buffer &base = buffer;
-  fmt::format_context ctx(std::back_inserter(base), "", fmt::format_args());
+  fmt::format_context ctx(fmt::detail::buffer_appender<char>{buffer},
+                          fmt::format_args());
   fmt::format_specs spec;
   test_arg_formatter af(ctx, spec);
-  visit(af, fmt::internal::make_arg<fmt::format_context>(TestEnum()));
-  EXPECT_EQ("TestEnum", std::string(buffer.data(), buffer.size()));
+  fmt::visit_format_arg(
+      af, fmt::detail::make_arg<fmt::format_context>(streamable_enum()));
+  EXPECT_EQ("streamable_enum", std::string(buffer.data(), buffer.size()));
 }
 
 TEST(OStreamTest, Format) {
@@ -75,20 +96,22 @@ TEST(OStreamTest, Format) {
 TEST(OStreamTest, FormatSpecs) {
   EXPECT_EQ("def  ", format("{0:<5}", TestString("def")));
   EXPECT_EQ("  def", format("{0:>5}", TestString("def")));
-  EXPECT_THROW_MSG(format("{0:=5}", TestString("def")),
-      format_error, "format specifier requires numeric argument");
+#if FMT_DEPRECATED_NUMERIC_ALIGN
+  EXPECT_THROW_MSG(format("{0:=5}", TestString("def")), format_error,
+                   "format specifier requires numeric argument");
+#endif
   EXPECT_EQ(" def ", format("{0:^5}", TestString("def")));
   EXPECT_EQ("def**", format("{0:*<5}", TestString("def")));
-  EXPECT_THROW_MSG(format("{0:+}", TestString()),
-      format_error, "format specifier requires numeric argument");
-  EXPECT_THROW_MSG(format("{0:-}", TestString()),
-      format_error, "format specifier requires numeric argument");
-  EXPECT_THROW_MSG(format("{0: }", TestString()),
-      format_error, "format specifier requires numeric argument");
-  EXPECT_THROW_MSG(format("{0:#}", TestString()),
-      format_error, "format specifier requires numeric argument");
-  EXPECT_THROW_MSG(format("{0:05}", TestString()),
-      format_error, "format specifier requires numeric argument");
+  EXPECT_THROW_MSG(format("{0:+}", TestString()), format_error,
+                   "format specifier requires numeric argument");
+  EXPECT_THROW_MSG(format("{0:-}", TestString()), format_error,
+                   "format specifier requires numeric argument");
+  EXPECT_THROW_MSG(format("{0: }", TestString()), format_error,
+                   "format specifier requires numeric argument");
+  EXPECT_THROW_MSG(format("{0:#}", TestString()), format_error,
+                   "format specifier requires numeric argument");
+  EXPECT_THROW_MSG(format("{0:05}", TestString()), format_error,
+                   "format specifier requires numeric argument");
   EXPECT_EQ("test         ", format("{0:13}", TestString("test")));
   EXPECT_EQ("test         ", format("{0:{1}}", TestString("test"), 13));
   EXPECT_EQ("te", format("{0:.2}", TestString("test")));
@@ -96,7 +119,7 @@ TEST(OStreamTest, FormatSpecs) {
 }
 
 struct EmptyTest {};
-static std::ostream &operator<<(std::ostream &os, EmptyTest) {
+static std::ostream& operator<<(std::ostream& os, EmptyTest) {
   return os << "";
 }
 
@@ -116,47 +139,47 @@ TEST(OStreamTest, Print) {
 TEST(OStreamTest, WriteToOStream) {
   std::ostringstream os;
   fmt::memory_buffer buffer;
-  const char *foo = "foo";
+  const char* foo = "foo";
   buffer.append(foo, foo + std::strlen(foo));
-  fmt::internal::write(os, buffer);
+  fmt::detail::write_buffer(os, buffer);
   EXPECT_EQ("foo", os.str());
 }
 
 TEST(OStreamTest, WriteToOStreamMaxSize) {
-  std::size_t max_size = std::numeric_limits<std::size_t>::max();
-  std::streamsize max_streamsize = std::numeric_limits<std::streamsize>::max();
-  if (max_size <= fmt::internal::to_unsigned(max_streamsize))
-    return;
+  size_t max_size = fmt::detail::max_value<size_t>();
+  std::streamsize max_streamsize = fmt::detail::max_value<std::streamsize>();
+  if (max_size <= fmt::detail::to_unsigned(max_streamsize)) return;
 
-  struct test_buffer : fmt::internal::buffer {
-    explicit test_buffer(std::size_t size) { resize(size); }
-    void grow(std::size_t) {}
+  struct test_buffer final : fmt::detail::buffer<char> {
+    explicit test_buffer(size_t size)
+      : fmt::detail::buffer<char>(nullptr, size, size) {}
+    void grow(size_t) {}
   } buffer(max_size);
 
   struct mock_streambuf : std::streambuf {
-    MOCK_METHOD2(xsputn, std::streamsize (const void *s, std::streamsize n));
-    std::streamsize xsputn(const char *s, std::streamsize n) {
-      const void *v = s;
+    MOCK_METHOD2(xsputn, std::streamsize(const void* s, std::streamsize n));
+    std::streamsize xsputn(const char* s, std::streamsize n) {
+      const void* v = s;
       return xsputn(v, n);
     }
   } streambuf;
 
   struct test_ostream : std::ostream {
-    explicit test_ostream(mock_streambuf &buffer) : std::ostream(&buffer) {}
+    explicit test_ostream(mock_streambuf& buffer) : std::ostream(&buffer) {}
   } os(streambuf);
 
   testing::InSequence sequence;
-  const char *data = FMT_NULL;
+  const char* data = nullptr;
   typedef std::make_unsigned<std::streamsize>::type ustreamsize;
   ustreamsize size = max_size;
   do {
-    auto n = std::min(size, fmt::internal::to_unsigned(max_streamsize));
+    auto n = std::min(size, fmt::detail::to_unsigned(max_streamsize));
     EXPECT_CALL(streambuf, xsputn(data, static_cast<std::streamsize>(n)))
         .WillOnce(testing::Return(max_streamsize));
     data += n;
     size -= n;
   } while (size != 0);
-  fmt::internal::write(os, buffer);
+  fmt::detail::write_buffer(os, buffer);
 }
 
 TEST(OStreamTest, Join) {
@@ -166,18 +189,40 @@ TEST(OStreamTest, Join) {
 
 #if FMT_USE_CONSTEXPR
 TEST(OStreamTest, ConstexprString) {
-  EXPECT_EQ("42", format(fmt("{}"), std::string("42")));
+  EXPECT_EQ("42", format(FMT_STRING("{}"), std::string("42")));
+  EXPECT_EQ("a string", format(FMT_STRING("{0}"), TestString("a string")));
 }
 #endif
 
 namespace fmt_test {
 struct ABC {};
 
-template <typename Output> Output &operator<<(Output &out, ABC) {
+template <typename Output> Output& operator<<(Output& out, ABC) {
   out << "ABC";
   return out;
 }
-} // namespace fmt_test
+}  // namespace fmt_test
+
+template <typename T> struct TestTemplate {};
+
+template <typename T>
+std::ostream& operator<<(std::ostream& os, TestTemplate<T>) {
+  return os << 1;
+}
+
+namespace fmt {
+template <typename T> struct formatter<TestTemplate<T>> : formatter<int> {
+  template <typename FormatContext>
+  typename FormatContext::iterator format(TestTemplate<T>, FormatContext& ctx) {
+    return formatter<int>::format(2, ctx);
+  }
+};
+}  // namespace fmt
+
+#if !FMT_GCC_VERSION || FMT_GCC_VERSION >= 407
+TEST(OStreamTest, Template) {
+  EXPECT_EQ("2", fmt::format("{}", TestTemplate<int>()));
+}
 
 TEST(FormatTest, FormatToN) {
   char buffer[4];
@@ -191,6 +236,7 @@ TEST(FormatTest, FormatToN) {
   EXPECT_EQ(buffer + 3, result.out);
   EXPECT_EQ("xABx", fmt::string_view(buffer, 4));
 }
+#endif
 
 #if FMT_USE_USER_DEFINED_LITERALS
 TEST(FormatTest, UDL) {
@@ -198,3 +244,82 @@ TEST(FormatTest, UDL) {
   EXPECT_EQ("{}"_format("test"), "test");
 }
 #endif
+
+template <typename T> struct convertible {
+  T value;
+  explicit convertible(const T& val) : value(val) {}
+  operator T() const { return value; }
+};
+
+TEST(OStreamTest, DisableBuiltinOStreamOperators) {
+  EXPECT_EQ("42", fmt::format("{:d}", convertible<unsigned short>(42)));
+  EXPECT_EQ(L"42", fmt::format(L"{:d}", convertible<unsigned short>(42)));
+  EXPECT_EQ("foo", fmt::format("{}", convertible<const char*>("foo")));
+}
+
+struct explicitly_convertible_to_string_like {
+  template <typename String,
+            typename = typename std::enable_if<std::is_constructible<
+                String, const char*, size_t>::value>::type>
+  explicit operator String() const {
+    return String("foo", 3u);
+  }
+};
+
+std::ostream& operator<<(std::ostream& os,
+                         explicitly_convertible_to_string_like) {
+  return os << "bar";
+}
+
+TEST(OStreamTest, FormatExplicitlyConvertibleToStringLike) {
+  EXPECT_EQ("bar", fmt::format("{}", explicitly_convertible_to_string_like()));
+}
+
+#ifdef FMT_USE_STRING_VIEW
+struct explicitly_convertible_to_std_string_view {
+  explicit operator fmt::detail::std_string_view<char>() const {
+    return {"foo", 3u};
+  }
+};
+
+std::ostream& operator<<(std::ostream& os,
+                         explicitly_convertible_to_std_string_view) {
+  return os << "bar";
+}
+
+TEST(OStreamTest, FormatExplicitlyConvertibleToStdStringView) {
+  EXPECT_EQ("bar", fmt::format("{}", explicitly_convertible_to_string_like()));
+}
+#endif  // FMT_USE_STRING_VIEW
+
+struct streamable_and_convertible_to_bool {
+  operator bool() const { return true; }
+};
+
+std::ostream& operator<<(std::ostream& os, streamable_and_convertible_to_bool) {
+  return os << "foo";
+}
+
+TEST(OStreamTest, FormatConvertibleToBool) {
+  EXPECT_EQ("foo", fmt::format("{}", streamable_and_convertible_to_bool()));
+}
+
+struct copyfmt_test {};
+
+std::ostream& operator<<(std::ostream& os, copyfmt_test) {
+  std::ios ios(nullptr);
+  ios.copyfmt(os);
+  return os << "foo";
+}
+
+TEST(OStreamTest, CopyFmt) {
+  EXPECT_EQ("foo", fmt::format("{}", copyfmt_test()));
+}
+
+TEST(OStreamTest, CompileTimeString) {
+  EXPECT_EQ("42", fmt::format(FMT_STRING("{}"), 42));
+}
+
+TEST(OStreamTest, ToString) {
+  EXPECT_EQ("ABC", fmt::to_string(fmt_test::ABC()));
+}

test/posix-mock-test.cc

@@ -6,21 +6,24 @@
 // For the license information refer to format.h.
 
 // Disable bogus MSVC warnings.
-#ifdef _MSC_VER
-# define _CRT_SECURE_NO_WARNINGS
+#ifndef _CRT_SECURE_NO_WARNINGS
+#  define _CRT_SECURE_NO_WARNINGS
 #endif
 
 #include "posix-mock.h"
-#include "../src/posix.cc"
 
 #include <errno.h>
 #include <fcntl.h>
+
 #include <climits>
+#include <memory>
+
+#include "../src/os.cc"
 
 #ifdef _WIN32
-# include <io.h>
-# undef max
-# undef ERROR
+#  include <io.h>
+#  undef max
+#  undef ERROR
 #endif
 
 #include "gmock.h"
@@ -29,12 +32,10 @@
 
 using fmt::buffered_file;
 using fmt::error_code;
-using fmt::file;
 
-using testing::internal::scoped_ptr;
 using testing::_;
-using testing::StrEq;
 using testing::Return;
+using testing::StrEq;
 
 namespace {
 int open_count;
@@ -48,29 +49,29 @@ int pipe_count;
 int fopen_count;
 int fclose_count;
 int fileno_count;
-std::size_t read_nbyte;
-std::size_t write_nbyte;
+size_t read_nbyte;
+size_t write_nbyte;
 bool sysconf_error;
 
-enum FStatSimulation { NONE, MAX_SIZE, ERROR } fstat_sim;
-}
+enum { NONE, MAX_SIZE, ERROR } fstat_sim;
+}  // namespace
 
 #define EMULATE_EINTR(func, error_result) \
-  if (func##_count != 0) { \
-    if (func##_count++ != 3) { \
-      errno = EINTR; \
-      return error_result; \
-    } \
+  if (func##_count != 0) {                \
+    if (func##_count++ != 3) {            \
+      errno = EINTR;                      \
+      return error_result;                \
+    }                                     \
   }
 
 #ifndef _MSC_VER
-int test::open(const char *path, int oflag, int mode) {
+int test::open(const char* path, int oflag, int mode) {
   EMULATE_EINTR(open, -1);
   return ::open(path, oflag, mode);
 }
 #else
-errno_t test::sopen_s(
-    int* pfh, const char *filename, int oflag, int shflag, int pmode) {
+errno_t test::sopen_s(int* pfh, const char* filename, int oflag, int shflag,
+                      int pmode) {
   EMULATE_EINTR(open, EINTR);
   return _sopen_s(pfh, filename, oflag, shflag, pmode);
 }
@@ -80,8 +81,7 @@ errno_t test::sopen_s(
 
 long test::sysconf(int name) {
   long result = ::sysconf(name);
-  if (!sysconf_error)
-    return result;
+  if (!sysconf_error) return result;
   // Simulate an error.
   errno = EINVAL;
   return -1;
@@ -89,10 +89,9 @@ long test::sysconf(int name) {
 
 static off_t max_file_size() { return std::numeric_limits<off_t>::max(); }
 
-int test::fstat(int fd, struct stat *buf) {
+int test::fstat(int fd, struct stat* buf) {
   int result = ::fstat(fd, buf);
-  if (fstat_sim == MAX_SIZE)
-    buf->st_size = max_file_size();
+  if (fstat_sim == MAX_SIZE) buf->st_size = max_file_size();
   return result;
 }
 
@@ -132,18 +131,18 @@ int test::dup2(int fildes, int fildes2) {
   return ::FMT_POSIX(dup2(fildes, fildes2));
 }
 
-FILE *test::fdopen(int fildes, const char *mode) {
-  EMULATE_EINTR(fdopen, FMT_NULL);
+FILE* test::fdopen(int fildes, const char* mode) {
+  EMULATE_EINTR(fdopen, nullptr);
   return ::FMT_POSIX(fdopen(fildes, mode));
 }
 
-test::ssize_t test::read(int fildes, void *buf, test::size_t nbyte) {
+test::ssize_t test::read(int fildes, void* buf, test::size_t nbyte) {
   read_nbyte = nbyte;
   EMULATE_EINTR(read, -1);
   return ::FMT_POSIX(read(fildes, buf, nbyte));
 }
 
-test::ssize_t test::write(int fildes, const void *buf, test::size_t nbyte) {
+test::ssize_t test::write(int fildes, const void* buf, test::size_t nbyte) {
   write_nbyte = nbyte;
   EMULATE_EINTR(write, -1);
   return ::FMT_POSIX(write(fildes, buf, nbyte));
@@ -155,23 +154,23 @@ int test::pipe(int fildes[2]) {
   return ::pipe(fildes);
 }
 #else
-int test::pipe(int *pfds, unsigned psize, int textmode) {
+int test::pipe(int* pfds, unsigned psize, int textmode) {
   EMULATE_EINTR(pipe, -1);
   return _pipe(pfds, psize, textmode);
 }
 #endif
 
-FILE *test::fopen(const char *filename, const char *mode) {
-  EMULATE_EINTR(fopen, FMT_NULL);
+FILE* test::fopen(const char* filename, const char* mode) {
+  EMULATE_EINTR(fopen, nullptr);
   return ::fopen(filename, mode);
 }
 
-int test::fclose(FILE *stream) {
+int test::fclose(FILE* stream) {
   EMULATE_EINTR(fclose, EOF);
   return ::fclose(stream);
 }
 
-int (test::fileno)(FILE *stream) {
+int(test::fileno)(FILE* stream) {
   EMULATE_EINTR(fileno, -1);
 #ifdef fileno
   return FMT_POSIX(fileno(stream));
@@ -181,18 +180,18 @@ int (test::fileno)(FILE *stream) {
 }
 
 #ifndef _WIN32
-# define EXPECT_RETRY(statement, func, message) \
-    func##_count = 1; \
-    statement; \
-    EXPECT_EQ(4, func##_count); \
+#  define EXPECT_RETRY(statement, func, message) \
+    func##_count = 1;                            \
+    statement;                                   \
+    EXPECT_EQ(4, func##_count);                  \
     func##_count = 0;
-# define EXPECT_EQ_POSIX(expected, actual) EXPECT_EQ(expected, actual)
+#  define EXPECT_EQ_POSIX(expected, actual) EXPECT_EQ(expected, actual)
 #else
-# define EXPECT_RETRY(statement, func, message) \
-    func##_count = 1; \
+#  define EXPECT_RETRY(statement, func, message)    \
+    func##_count = 1;                               \
     EXPECT_SYSTEM_ERROR(statement, EINTR, message); \
     func##_count = 0;
-# define EXPECT_EQ_POSIX(expected, actual)
+#  define EXPECT_EQ_POSIX(expected, actual)
 #endif
 
 static void write_file(fmt::cstring_view filename, fmt::string_view content) {
@@ -200,42 +199,48 @@ static void write_file(fmt::cstring_view filename, fmt::string_view content) {
   f.print("{}", content);
 }
 
+#if FMT_USE_FCNTL
+using fmt::file;
+
 TEST(UtilTest, GetPageSize) {
-#ifdef _WIN32
+#  ifdef _WIN32
   SYSTEM_INFO si = {};
   GetSystemInfo(&si);
   EXPECT_EQ(si.dwPageSize, fmt::getpagesize());
-#else
+#  else
   EXPECT_EQ(sysconf(_SC_PAGESIZE), fmt::getpagesize());
   sysconf_error = true;
-  EXPECT_SYSTEM_ERROR(
-      fmt::getpagesize(), EINVAL, "cannot get memory page size");
+  EXPECT_SYSTEM_ERROR(fmt::getpagesize(), EINVAL,
+                      "cannot get memory page size");
   sysconf_error = false;
-#endif
+#  endif
 }
 
 TEST(FileTest, OpenRetry) {
-  write_file("test", "there must be something here");
-  scoped_ptr<file> f{FMT_NULL};
-  EXPECT_RETRY(f.reset(new file("test", file::RDONLY)),
-               open, "cannot open file test");
-#ifndef _WIN32
+  write_file("temp", "there must be something here");
+  std::unique_ptr<file> f{nullptr};
+  EXPECT_RETRY(f.reset(new file("temp", file::RDONLY)), open,
+               "cannot open file temp");
+#  ifndef _WIN32
   char c = 0;
   f->read(&c, 1);
-#endif
+#  endif
 }
 
 TEST(FileTest, CloseNoRetryInDtor) {
   file read_end, write_end;
   file::pipe(read_end, write_end);
-  scoped_ptr<file> f(new file(std::move(read_end)));
+  std::unique_ptr<file> f(new file(std::move(read_end)));
   int saved_close_count = 0;
-  EXPECT_WRITE(stderr, {
-    close_count = 1;
-    f.reset(FMT_NULL);
-    saved_close_count = close_count;
-    close_count = 0;
-  }, format_system_error(EINTR, "cannot close file") + "\n");
+  EXPECT_WRITE(
+      stderr,
+      {
+        close_count = 1;
+        f.reset(nullptr);
+        saved_close_count = close_count;
+        close_count = 0;
+      },
+      format_system_error(EINTR, "cannot close file") + "\n");
   EXPECT_EQ(2, saved_close_count);
 }
 
@@ -250,26 +255,26 @@ TEST(FileTest, CloseNoRetry) {
 
 TEST(FileTest, Size) {
   std::string content = "top secret, destroy before reading";
-  write_file("test", content);
-  file f("test", file::RDONLY);
+  write_file("temp", content);
+  file f("temp", file::RDONLY);
   EXPECT_GE(f.size(), 0);
   EXPECT_EQ(content.size(), static_cast<unsigned long long>(f.size()));
-#ifdef _WIN32
+#  ifdef _WIN32
   fmt::memory_buffer message;
-  fmt::internal::format_windows_error(
-      message, ERROR_ACCESS_DENIED, "cannot get file size");
+  fmt::detail::format_windows_error(message, ERROR_ACCESS_DENIED,
+                                    "cannot get file size");
   fstat_sim = ERROR;
   EXPECT_THROW_MSG(f.size(), fmt::windows_error, fmt::to_string(message));
   fstat_sim = NONE;
-#else
+#  else
   f.close();
   EXPECT_SYSTEM_ERROR(f.size(), EBADF, "cannot get file attributes");
-#endif
+#  endif
 }
 
 TEST(FileTest, MaxSize) {
-  write_file("test", "");
-  file f("test", file::RDONLY);
+  write_file("temp", "");
+  file f("temp", file::RDONLY);
   fstat_sim = MAX_SIZE;
   EXPECT_GE(f.size(), 0);
   EXPECT_EQ(max_file_size(), f.size());
@@ -283,9 +288,9 @@ TEST(FileTest, ReadRetry) {
   write_end.write("test", SIZE);
   write_end.close();
   char buffer[SIZE];
-  std::size_t count = 0;
-  EXPECT_RETRY(count = read_end.read(buffer, SIZE),
-      read, "cannot read from file");
+  size_t count = 0;
+  EXPECT_RETRY(count = read_end.read(buffer, SIZE), read,
+               "cannot read from file");
   EXPECT_EQ_POSIX(static_cast<std::streamsize>(SIZE), count);
 }
 
@@ -293,27 +298,26 @@ TEST(FileTest, WriteRetry) {
   file read_end, write_end;
   file::pipe(read_end, write_end);
   enum { SIZE = 4 };
-  std::size_t count = 0;
-  EXPECT_RETRY(count = write_end.write("test", SIZE),
-      write, "cannot write to file");
+  size_t count = 0;
+  EXPECT_RETRY(count = write_end.write("test", SIZE), write,
+               "cannot write to file");
   write_end.close();
-#ifndef _WIN32
+#  ifndef _WIN32
   EXPECT_EQ(static_cast<std::streamsize>(SIZE), count);
   char buffer[SIZE + 1];
   read_end.read(buffer, SIZE);
   buffer[SIZE] = '\0';
   EXPECT_STREQ("test", buffer);
-#endif
+#  endif
 }
 
-#ifdef _WIN32
+#  ifdef _WIN32
 TEST(FileTest, ConvertReadCount) {
   file read_end, write_end;
   file::pipe(read_end, write_end);
   char c;
-  std::size_t size = UINT_MAX;
-  if (sizeof(unsigned) != sizeof(std::size_t))
-    ++size;
+  size_t size = UINT_MAX;
+  if (sizeof(unsigned) != sizeof(size_t)) ++size;
   read_count = 1;
   read_nbyte = 0;
   EXPECT_THROW(read_end.read(&c, size), fmt::system_error);
@@ -325,21 +329,21 @@ TEST(FileTest, ConvertWriteCount) {
   file read_end, write_end;
   file::pipe(read_end, write_end);
   char c;
-  std::size_t size = UINT_MAX;
-  if (sizeof(unsigned) != sizeof(std::size_t))
-    ++size;
+  size_t size = UINT_MAX;
+  if (sizeof(unsigned) != sizeof(size_t)) ++size;
   write_count = 1;
   write_nbyte = 0;
   EXPECT_THROW(write_end.write(&c, size), fmt::system_error);
   write_count = 0;
   EXPECT_EQ(UINT_MAX, write_nbyte);
 }
-#endif
+#  endif
 
 TEST(FileTest, DupNoRetry) {
   int stdout_fd = FMT_POSIX(fileno(stdout));
   dup_count = 1;
-  EXPECT_SYSTEM_ERROR(file::dup(stdout_fd), EINTR,
+  EXPECT_SYSTEM_ERROR(
+      file::dup(stdout_fd), EINTR,
       fmt::format("cannot duplicate file descriptor {}", stdout_fd));
   dup_count = 0;
 }
@@ -348,8 +352,8 @@ TEST(FileTest, Dup2Retry) {
   int stdout_fd = FMT_POSIX(fileno(stdout));
   file f1 = file::dup(stdout_fd), f2 = file::dup(stdout_fd);
   EXPECT_RETRY(f1.dup2(f2.descriptor()), dup2,
-      fmt::format("cannot duplicate file descriptor {} to {}",
-      f1.descriptor(), f2.descriptor()));
+               fmt::format("cannot duplicate file descriptor {} to {}",
+                           f1.descriptor(), f2.descriptor()));
 }
 
 TEST(FileTest, Dup2NoExceptRetry) {
@@ -358,19 +362,19 @@ TEST(FileTest, Dup2NoExceptRetry) {
   error_code ec;
   dup2_count = 1;
   f1.dup2(f2.descriptor(), ec);
-#ifndef _WIN32
+#  ifndef _WIN32
   EXPECT_EQ(4, dup2_count);
-#else
+#  else
   EXPECT_EQ(EINTR, ec.get());
-#endif
+#  endif
   dup2_count = 0;
 }
 
 TEST(FileTest, PipeNoRetry) {
   file read_end, write_end;
   pipe_count = 1;
-  EXPECT_SYSTEM_ERROR(
-      file::pipe(read_end, write_end), EINTR, "cannot create pipe");
+  EXPECT_SYSTEM_ERROR(file::pipe(read_end, write_end), EINTR,
+                      "cannot create pipe");
   pipe_count = 0;
 }
 
@@ -378,34 +382,37 @@ TEST(FileTest, FdopenNoRetry) {
   file read_end, write_end;
   file::pipe(read_end, write_end);
   fdopen_count = 1;
-  EXPECT_SYSTEM_ERROR(read_end.fdopen("r"),
-      EINTR, "cannot associate stream with file descriptor");
+  EXPECT_SYSTEM_ERROR(read_end.fdopen("r"), EINTR,
+                      "cannot associate stream with file descriptor");
   fdopen_count = 0;
 }
 
 TEST(BufferedFileTest, OpenRetry) {
-  write_file("test", "there must be something here");
-  scoped_ptr<buffered_file> f{FMT_NULL};
-  EXPECT_RETRY(f.reset(new buffered_file("test", "r")),
-               fopen, "cannot open file test");
-#ifndef _WIN32
+  write_file("temp", "there must be something here");
+  std::unique_ptr<buffered_file> f{nullptr};
+  EXPECT_RETRY(f.reset(new buffered_file("temp", "r")), fopen,
+               "cannot open file temp");
+#  ifndef _WIN32
   char c = 0;
   if (fread(&c, 1, 1, f->get()) < 1)
     throw fmt::system_error(errno, "fread failed");
-#endif
+#  endif
 }
 
 TEST(BufferedFileTest, CloseNoRetryInDtor) {
   file read_end, write_end;
   file::pipe(read_end, write_end);
-  scoped_ptr<buffered_file> f(new buffered_file(read_end.fdopen("r")));
+  std::unique_ptr<buffered_file> f(new buffered_file(read_end.fdopen("r")));
   int saved_fclose_count = 0;
-  EXPECT_WRITE(stderr, {
-    fclose_count = 1;
-    f.reset(FMT_NULL);
-    saved_fclose_count = fclose_count;
-    fclose_count = 0;
-  }, format_system_error(EINTR, "cannot close file") + "\n");
+  EXPECT_WRITE(
+      stderr,
+      {
+        fclose_count = 1;
+        f.reset(nullptr);
+        saved_fclose_count = fclose_count;
+        fclose_count = 0;
+      },
+      format_system_error(EINTR, "cannot close file") + "\n");
   EXPECT_EQ(2, saved_fclose_count);
 }
 
@@ -428,111 +435,123 @@ TEST(BufferedFileTest, FilenoNoRetry) {
   EXPECT_EQ(2, fileno_count);
   fileno_count = 0;
 }
+#endif  // FMT_USE_FCNTL
 
-struct TestMock {
-  static TestMock *instance;
-} *TestMock::instance;
+struct test_mock {
+  static test_mock* instance;
+} * test_mock::instance;
 
 TEST(ScopedMock, Scope) {
   {
-    ScopedMock<TestMock> mock;
-    EXPECT_EQ(&mock, TestMock::instance);
-    TestMock &copy = mock;
+    ScopedMock<test_mock> mock;
+    EXPECT_EQ(&mock, test_mock::instance);
+    test_mock& copy = mock;
     static_cast<void>(copy);
   }
-  EXPECT_EQ(FMT_NULL, TestMock::instance);
+  EXPECT_EQ(nullptr, test_mock::instance);
 }
 
 #ifdef FMT_LOCALE
 
-typedef fmt::Locale::Type LocaleType;
+typedef fmt::locale::type locale_type;
 
-struct LocaleMock {
-  static LocaleMock *instance;
-  MOCK_METHOD3(newlocale, LocaleType (int category_mask, const char *locale,
-                                      LocaleType base));
-  MOCK_METHOD1(freelocale, void (LocaleType locale));
+struct locale_mock {
+  static locale_mock* instance;
+  MOCK_METHOD3(newlocale, locale_type(int category_mask, const char* locale,
+                                      locale_type base));
+  MOCK_METHOD1(freelocale, void(locale_type locale));
 
-  MOCK_METHOD3(strtod_l, double (const char *nptr, char **endptr,
-                                 LocaleType locale));
-} *LocaleMock::instance;
+  MOCK_METHOD3(strtod_l,
+               double(const char* nptr, char** endptr, locale_type locale));
+} * locale_mock::instance;
 
-#ifdef _MSC_VER
-# pragma warning(push)
-# pragma warning(disable: 4273)
+#  ifdef _MSC_VER
+#    pragma warning(push)
+#    pragma warning(disable : 4273)
+#    ifdef __clang__
+#      pragma clang diagnostic push
+#      pragma clang diagnostic ignored "-Winconsistent-dllimport"
+#    endif
 
-_locale_t _create_locale(int category, const char *locale) {
-  return LocaleMock::instance->newlocale(category, locale, 0);
+_locale_t _create_locale(int category, const char* locale) {
+  return locale_mock::instance->newlocale(category, locale, 0);
 }
 
 void _free_locale(_locale_t locale) {
-  LocaleMock::instance->freelocale(locale);
+  locale_mock::instance->freelocale(locale);
 }
 
-double _strtod_l(const char *nptr, char **endptr, _locale_t locale) {
-  return LocaleMock::instance->strtod_l(nptr, endptr, locale);
+double _strtod_l(const char* nptr, char** endptr, _locale_t locale) {
+  return locale_mock::instance->strtod_l(nptr, endptr, locale);
 }
-# pragma warning(pop)
-#endif
+#    ifdef __clang__
+#      pragma clang diagnostic pop
+#    endif
+#    pragma warning(pop)
+#  endif
 
-#if defined(__THROW) && FMT_GCC_VERSION > 0 && FMT_GCC_VERSION <= 408
-#define FMT_LOCALE_THROW __THROW
-#else
-#define FMT_LOCALE_THROW
-#endif
+#  if defined(__THROW) && FMT_GCC_VERSION > 0 && FMT_GCC_VERSION <= 408
+#    define FMT_LOCALE_THROW __THROW
+#  else
+#    define FMT_LOCALE_THROW
+#  endif
 
-LocaleType newlocale(int category_mask, const char *locale, LocaleType base) FMT_LOCALE_THROW {
-  return LocaleMock::instance->newlocale(category_mask, locale, base);
-}
-
-#if defined(__APPLE__) || (defined(__FreeBSD__) && __FreeBSD_version < 1200002)
+#  if defined(__APPLE__) || \
+      (defined(__FreeBSD__) && __FreeBSD_version < 1200002)
 typedef int FreeLocaleResult;
-#else
+#  else
 typedef void FreeLocaleResult;
-#endif
+#  endif
 
-FreeLocaleResult freelocale(LocaleType locale) FMT_LOCALE_THROW {
-  LocaleMock::instance->freelocale(locale);
+FreeLocaleResult freelocale(locale_type locale) FMT_LOCALE_THROW {
+  locale_mock::instance->freelocale(locale);
   return FreeLocaleResult();
 }
 
-double strtod_l(const char *nptr, char **endptr, LocaleType locale) FMT_LOCALE_THROW {
-  return LocaleMock::instance->strtod_l(nptr, endptr, locale);
+double strtod_l(const char* nptr, char** endptr,
+                locale_type locale) FMT_LOCALE_THROW {
+  return locale_mock::instance->strtod_l(nptr, endptr, locale);
 }
 
-#undef FMT_LOCALE_THROW
+#  undef FMT_LOCALE_THROW
+
+#  ifndef _WIN32
+locale_t test::newlocale(int category_mask, const char* locale, locale_t base) {
+  return locale_mock::instance->newlocale(category_mask, locale, base);
+}
 
 TEST(LocaleTest, LocaleMock) {
-  ScopedMock<LocaleMock> mock;
-  LocaleType locale = reinterpret_cast<LocaleType>(11);
+  ScopedMock<locale_mock> mock;
+  locale_type locale = reinterpret_cast<locale_type>(11);
   EXPECT_CALL(mock, newlocale(222, StrEq("foo"), locale));
-  newlocale(222, "foo", locale);
+  FMT_SYSTEM(newlocale(222, "foo", locale));
 }
+#  endif
 
 TEST(LocaleTest, Locale) {
-#ifndef LC_NUMERIC_MASK
+#  ifndef LC_NUMERIC_MASK
   enum { LC_NUMERIC_MASK = LC_NUMERIC };
-#endif
-  ScopedMock<LocaleMock> mock;
-  LocaleType impl = reinterpret_cast<LocaleType>(42);
-  EXPECT_CALL(mock, newlocale(LC_NUMERIC_MASK, StrEq("C"), FMT_NULL))
+#  endif
+  ScopedMock<locale_mock> mock;
+  locale_type impl = reinterpret_cast<locale_type>(42);
+  EXPECT_CALL(mock, newlocale(LC_NUMERIC_MASK, StrEq("C"), nullptr))
       .WillOnce(Return(impl));
   EXPECT_CALL(mock, freelocale(impl));
-  fmt::Locale locale;
-  EXPECT_EQ(impl, locale.get());
+  fmt::locale loc;
+  EXPECT_EQ(impl, loc.get());
 }
 
 TEST(LocaleTest, Strtod) {
-  ScopedMock<LocaleMock> mock;
+  ScopedMock<locale_mock> mock;
   EXPECT_CALL(mock, newlocale(_, _, _))
-      .WillOnce(Return(reinterpret_cast<LocaleType>(42)));
+      .WillOnce(Return(reinterpret_cast<locale_type>(42)));
   EXPECT_CALL(mock, freelocale(_));
-  fmt::Locale locale;
-  const char *str = "4.2";
+  fmt::locale loc;
+  const char* str = "4.2";
   char end = 'x';
-  EXPECT_CALL(mock, strtod_l(str, _, locale.get()))
+  EXPECT_CALL(mock, strtod_l(str, _, loc.get()))
       .WillOnce(testing::DoAll(testing::SetArgPointee<1>(&end), Return(777)));
-  EXPECT_EQ(777, locale.strtod(str));
+  EXPECT_EQ(777, loc.strtod(str));
   EXPECT_EQ(&end, str);
 }
 

test/posix-mock.h

@@ -9,13 +9,17 @@
 #define FMT_POSIX_TEST_H
 
 #include <errno.h>
+#include <locale.h>
 #include <stdio.h>
+#ifdef __APPLE__
+#  include <xlocale.h>
+#endif
 
 #ifdef _WIN32
-# include <windows.h>
+#  include <windows.h>
 #else
-# include <sys/param.h>  // for FreeBSD version
-# include <sys/types.h>  // for ssize_t
+#  include <sys/param.h>  // for FreeBSD version
+#  include <sys/types.h>  // for ssize_t
 #endif
 
 #ifndef _MSC_VER
@@ -28,13 +32,13 @@ namespace test {
 // Size type for read and write.
 typedef size_t size_t;
 typedef ssize_t ssize_t;
-int open(const char *path, int oflag, int mode);
-int fstat(int fd, struct stat *buf);
+int open(const char* path, int oflag, int mode);
+int fstat(int fd, struct stat* buf);
 #else
 typedef unsigned size_t;
 typedef int ssize_t;
-errno_t sopen_s(
-    int* pfh, const char *filename, int oflag, int shflag, int pmode);
+errno_t sopen_s(int* pfh, const char* filename, int oflag, int shflag,
+                int pmode);
 #endif
 
 #ifndef _WIN32
@@ -48,20 +52,24 @@ int close(int fildes);
 int dup(int fildes);
 int dup2(int fildes, int fildes2);
 
-FILE *fdopen(int fildes, const char *mode);
+FILE* fdopen(int fildes, const char* mode);
 
-ssize_t read(int fildes, void *buf, size_t nbyte);
-ssize_t write(int fildes, const void *buf, size_t nbyte);
+ssize_t read(int fildes, void* buf, size_t nbyte);
+ssize_t write(int fildes, const void* buf, size_t nbyte);
 
 #ifndef _WIN32
 int pipe(int fildes[2]);
 #else
-int pipe(int *pfds, unsigned psize, int textmode);
+int pipe(int* pfds, unsigned psize, int textmode);
 #endif
 
-FILE *fopen(const char *filename, const char *mode);
-int fclose(FILE *stream);
-int (fileno)(FILE *stream);
+FILE* fopen(const char* filename, const char* mode);
+int fclose(FILE* stream);
+int(fileno)(FILE* stream);
+
+#if defined(FMT_LOCALE) && !defined(_WIN32)
+locale_t newlocale(int category_mask, const char* locale, locale_t base);
+#endif
 }  // namespace test
 
 #define FMT_SYSTEM(call) test::call

test/posix-test.cc

@@ -1,378 +0,0 @@
-// Formatting library for C++ - tests of the C++ interface to POSIX functions
-//
-// Copyright (c) 2012 - present, Victor Zverovich
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-#include <cstdlib>  // std::exit
-#include <cstring>
-
-#include "fmt/posix.h"
-#include "gtest-extra.h"
-#include "util.h"
-
-#ifdef fileno
-# undef fileno
-#endif
-
-using fmt::buffered_file;
-using fmt::error_code;
-using fmt::file;
-
-using testing::internal::scoped_ptr;
-
-// Checks if the file is open by reading one character from it.
-static bool isopen(int fd) {
-  char buffer;
-  return FMT_POSIX(read(fd, &buffer, 1)) == 1;
-}
-
-static bool isclosed(int fd) {
-  char buffer;
-  std::streamsize result = 0;
-  SUPPRESS_ASSERT(result = FMT_POSIX(read(fd, &buffer, 1)));
-  return result == -1 && errno == EBADF;
-}
-
-// Opens a file for reading.
-static file open_file() {
-  file read_end, write_end;
-  file::pipe(read_end, write_end);
-  write_end.write(FILE_CONTENT, std::strlen(FILE_CONTENT));
-  write_end.close();
-  return read_end;
-}
-
-// Attempts to write a string to a file.
-static void write(file &f, fmt::string_view s) {
-  std::size_t num_chars_left = s.size();
-  const char *ptr = s.data();
-  do {
-    std::size_t count = f.write(ptr, num_chars_left);
-    ptr += count;
-    // We can't write more than size_t bytes since num_chars_left
-    // has type size_t.
-    num_chars_left -= count;
-  } while (num_chars_left != 0);
-}
-
-TEST(BufferedFileTest, DefaultCtor) {
-  buffered_file f;
-  EXPECT_TRUE(f.get() == FMT_NULL);
-}
-
-TEST(BufferedFileTest, MoveCtor) {
-  buffered_file bf = open_buffered_file();
-  FILE *fp = bf.get();
-  EXPECT_TRUE(fp != FMT_NULL);
-  buffered_file bf2(std::move(bf));
-  EXPECT_EQ(fp, bf2.get());
-  EXPECT_TRUE(bf.get() == FMT_NULL);
-}
-
-TEST(BufferedFileTest, MoveAssignment) {
-  buffered_file bf = open_buffered_file();
-  FILE *fp = bf.get();
-  EXPECT_TRUE(fp != FMT_NULL);
-  buffered_file bf2;
-  bf2 = std::move(bf);
-  EXPECT_EQ(fp, bf2.get());
-  EXPECT_TRUE(bf.get() == FMT_NULL);
-}
-
-TEST(BufferedFileTest, MoveAssignmentClosesFile) {
-  buffered_file bf = open_buffered_file();
-  buffered_file bf2 = open_buffered_file();
-  int old_fd = bf2.fileno();
-  bf2 = std::move(bf);
-  EXPECT_TRUE(isclosed(old_fd));
-}
-
-TEST(BufferedFileTest, MoveFromTemporaryInCtor) {
-  FILE *fp = FMT_NULL;
-  buffered_file f(open_buffered_file(&fp));
-  EXPECT_EQ(fp, f.get());
-}
-
-TEST(BufferedFileTest, MoveFromTemporaryInAssignment) {
-  FILE *fp = FMT_NULL;
-  buffered_file f;
-  f = open_buffered_file(&fp);
-  EXPECT_EQ(fp, f.get());
-}
-
-TEST(BufferedFileTest, MoveFromTemporaryInAssignmentClosesFile) {
-  buffered_file f = open_buffered_file();
-  int old_fd = f.fileno();
-  f = open_buffered_file();
-  EXPECT_TRUE(isclosed(old_fd));
-}
-
-TEST(BufferedFileTest, CloseFileInDtor) {
-  int fd = 0;
-  {
-    buffered_file f = open_buffered_file();
-    fd = f.fileno();
-  }
-  EXPECT_TRUE(isclosed(fd));
-}
-
-TEST(BufferedFileTest, CloseErrorInDtor) {
-  scoped_ptr<buffered_file> f(new buffered_file(open_buffered_file()));
-  EXPECT_WRITE(stderr, {
-      // The close function must be called inside EXPECT_WRITE, otherwise
-      // the system may recycle closed file descriptor when redirecting the
-      // output in EXPECT_STDERR and the second close will break output
-      // redirection.
-      FMT_POSIX(close(f->fileno()));
-      SUPPRESS_ASSERT(f.reset(FMT_NULL));
-  }, format_system_error(EBADF, "cannot close file") + "\n");
-}
-
-TEST(BufferedFileTest, Close) {
-  buffered_file f = open_buffered_file();
-  int fd = f.fileno();
-  f.close();
-  EXPECT_TRUE(f.get() == FMT_NULL);
-  EXPECT_TRUE(isclosed(fd));
-}
-
-TEST(BufferedFileTest, CloseError) {
-  buffered_file f = open_buffered_file();
-  FMT_POSIX(close(f.fileno()));
-  EXPECT_SYSTEM_ERROR_NOASSERT(f.close(), EBADF, "cannot close file");
-  EXPECT_TRUE(f.get() == FMT_NULL);
-}
-
-TEST(BufferedFileTest, Fileno) {
-  buffered_file f;
-#ifndef __COVERITY__
-  // fileno on a null FILE pointer either crashes or returns an error.
-  // Disable Coverity because this is intentional.
-  EXPECT_DEATH_IF_SUPPORTED({
-    try {
-      f.fileno();
-    } catch (const fmt::system_error&) {
-      std::exit(1);
-    }
-  }, "");
-#endif
-  f = open_buffered_file();
-  EXPECT_TRUE(f.fileno() != -1);
-  file copy = file::dup(f.fileno());
-  EXPECT_READ(copy, FILE_CONTENT);
-}
-
-TEST(FileTest, DefaultCtor) {
-  file f;
-  EXPECT_EQ(-1, f.descriptor());
-}
-
-TEST(FileTest, OpenBufferedFileInCtor) {
-  FILE *fp = safe_fopen("test-file", "w");
-  std::fputs(FILE_CONTENT, fp);
-  std::fclose(fp);
-  file f("test-file", file::RDONLY);
-  ASSERT_TRUE(isopen(f.descriptor()));
-}
-
-TEST(FileTest, OpenBufferedFileError) {
-  EXPECT_SYSTEM_ERROR(file("nonexistent", file::RDONLY),
-      ENOENT, "cannot open file nonexistent");
-}
-
-TEST(FileTest, MoveCtor) {
-  file f = open_file();
-  int fd = f.descriptor();
-  EXPECT_NE(-1, fd);
-  file f2(std::move(f));
-  EXPECT_EQ(fd, f2.descriptor());
-  EXPECT_EQ(-1, f.descriptor());
-}
-
-TEST(FileTest, MoveAssignment) {
-  file f = open_file();
-  int fd = f.descriptor();
-  EXPECT_NE(-1, fd);
-  file f2;
-  f2 = std::move(f);
-  EXPECT_EQ(fd, f2.descriptor());
-  EXPECT_EQ(-1, f.descriptor());
-}
-
-TEST(FileTest, MoveAssignmentClosesFile) {
-  file f = open_file();
-  file f2 = open_file();
-  int old_fd = f2.descriptor();
-  f2 = std::move(f);
-  EXPECT_TRUE(isclosed(old_fd));
-}
-
-static file OpenBufferedFile(int &fd) {
-  file f = open_file();
-  fd = f.descriptor();
-  return f;
-}
-
-TEST(FileTest, MoveFromTemporaryInCtor) {
-  int fd = 0xdead;
-  file f(OpenBufferedFile(fd));
-  EXPECT_EQ(fd, f.descriptor());
-}
-
-TEST(FileTest, MoveFromTemporaryInAssignment) {
-  int fd = 0xdead;
-  file f;
-  f = OpenBufferedFile(fd);
-  EXPECT_EQ(fd, f.descriptor());
-}
-
-TEST(FileTest, MoveFromTemporaryInAssignmentClosesFile) {
-  int fd = 0xdead;
-  file f = open_file();
-  int old_fd = f.descriptor();
-  f = OpenBufferedFile(fd);
-  EXPECT_TRUE(isclosed(old_fd));
-}
-
-TEST(FileTest, CloseFileInDtor) {
-  int fd = 0;
-  {
-    file f = open_file();
-    fd = f.descriptor();
-  }
-  EXPECT_TRUE(isclosed(fd));
-}
-
-TEST(FileTest, CloseErrorInDtor) {
-  scoped_ptr<file> f(new file(open_file()));
-  EXPECT_WRITE(stderr, {
-      // The close function must be called inside EXPECT_WRITE, otherwise
-      // the system may recycle closed file descriptor when redirecting the
-      // output in EXPECT_STDERR and the second close will break output
-      // redirection.
-      FMT_POSIX(close(f->descriptor()));
-      SUPPRESS_ASSERT(f.reset(FMT_NULL));
-  }, format_system_error(EBADF, "cannot close file") + "\n");
-}
-
-TEST(FileTest, Close) {
-  file f = open_file();
-  int fd = f.descriptor();
-  f.close();
-  EXPECT_EQ(-1, f.descriptor());
-  EXPECT_TRUE(isclosed(fd));
-}
-
-TEST(FileTest, CloseError) {
-  file f = open_file();
-  FMT_POSIX(close(f.descriptor()));
-  EXPECT_SYSTEM_ERROR_NOASSERT(f.close(), EBADF, "cannot close file");
-  EXPECT_EQ(-1, f.descriptor());
-}
-
-TEST(FileTest, Read) {
-  file f = open_file();
-  EXPECT_READ(f, FILE_CONTENT);
-}
-
-TEST(FileTest, ReadError) {
-  file f("test-file", file::WRONLY);
-  char buf;
-  // We intentionally read from a file opened in the write-only mode to
-  // cause error.
-  EXPECT_SYSTEM_ERROR(f.read(&buf, 1), EBADF, "cannot read from file");
-}
-
-TEST(FileTest, Write) {
-  file read_end, write_end;
-  file::pipe(read_end, write_end);
-  write(write_end, "test");
-  write_end.close();
-  EXPECT_READ(read_end, "test");
-}
-
-TEST(FileTest, WriteError) {
-  file f("test-file", file::RDONLY);
-  // We intentionally write to a file opened in the read-only mode to
-  // cause error.
-  EXPECT_SYSTEM_ERROR(f.write(" ", 1), EBADF, "cannot write to file");
-}
-
-TEST(FileTest, Dup) {
-  file f = open_file();
-  file copy = file::dup(f.descriptor());
-  EXPECT_NE(f.descriptor(), copy.descriptor());
-  EXPECT_EQ(FILE_CONTENT, read(copy, std::strlen(FILE_CONTENT)));
-}
-
-#ifndef __COVERITY__
-TEST(FileTest, DupError) {
-  int value = -1;
-  EXPECT_SYSTEM_ERROR_NOASSERT(file::dup(value),
-      EBADF, "cannot duplicate file descriptor -1");
-}
-#endif
-
-TEST(FileTest, Dup2) {
-  file f = open_file();
-  file copy = open_file();
-  f.dup2(copy.descriptor());
-  EXPECT_NE(f.descriptor(), copy.descriptor());
-  EXPECT_READ(copy, FILE_CONTENT);
-}
-
-TEST(FileTest, Dup2Error) {
-  file f = open_file();
-  EXPECT_SYSTEM_ERROR_NOASSERT(f.dup2(-1), EBADF,
-    fmt::format("cannot duplicate file descriptor {} to -1", f.descriptor()));
-}
-
-TEST(FileTest, Dup2NoExcept) {
-  file f = open_file();
-  file copy = open_file();
-  error_code ec;
-  f.dup2(copy.descriptor(), ec);
-  EXPECT_EQ(ec.get(), 0);
-  EXPECT_NE(f.descriptor(), copy.descriptor());
-  EXPECT_READ(copy, FILE_CONTENT);
-}
-
-TEST(FileTest, Dup2NoExceptError) {
-  file f = open_file();
-  error_code ec;
-  SUPPRESS_ASSERT(f.dup2(-1, ec));
-  EXPECT_EQ(EBADF, ec.get());
-}
-
-TEST(FileTest, Pipe) {
-  file read_end, write_end;
-  file::pipe(read_end, write_end);
-  EXPECT_NE(-1, read_end.descriptor());
-  EXPECT_NE(-1, write_end.descriptor());
-  write(write_end, "test");
-  EXPECT_READ(read_end, "test");
-}
-
-TEST(FileTest, Fdopen) {
-  file read_end, write_end;
-  file::pipe(read_end, write_end);
-  int read_fd = read_end.descriptor();
-  EXPECT_EQ(read_fd, FMT_POSIX(fileno(read_end.fdopen("r").get())));
-}
-
-TEST(FileTest, FdopenError) {
-  file f;
-  EXPECT_SYSTEM_ERROR_NOASSERT(
-      f.fdopen("r"), EBADF, "cannot associate stream with file descriptor");
-}
-
-#ifdef FMT_LOCALE
-TEST(LocaleTest, Strtod) {
-  fmt::Locale locale;
-  const char *start = "4.2", *ptr = start;
-  EXPECT_EQ(4.2, locale.strtod(ptr));
-  EXPECT_EQ(start + 3, ptr);
-}
-#endif

test/printf-test.cc

@@ -5,17 +5,19 @@
 //
 // For the license information refer to format.h.
 
+#include "fmt/printf.h"
+
 #include <cctype>
 #include <climits>
 #include <cstring>
 
 #include "fmt/core.h"
-#include "fmt/printf.h"
 #include "gtest-extra.h"
 #include "util.h"
 
 using fmt::format;
 using fmt::format_error;
+using fmt::detail::max_value;
 
 const unsigned BIG_NUM = INT_MAX + 1u;
 
@@ -35,17 +37,17 @@ static std::wstring make_positional(fmt::wstring_view format) {
 // A wrapper around fmt::sprintf to workaround bogus warnings about invalid
 // format strings in MSVC.
 template <typename... Args>
-std::string test_sprintf(fmt::string_view format, const Args &... args) {
+std::string test_sprintf(fmt::string_view format, const Args&... args) {
   return fmt::sprintf(format, args...);
 }
 template <typename... Args>
-std::wstring test_sprintf(fmt::wstring_view format, const Args &... args) {
+std::wstring test_sprintf(fmt::wstring_view format, const Args&... args) {
   return fmt::sprintf(format, args...);
 }
 
-#define EXPECT_PRINTF(expected_output, format, arg) \
+#define EXPECT_PRINTF(expected_output, format, arg)     \
   EXPECT_EQ(expected_output, test_sprintf(format, arg)) \
-    << "format: " << format; \
+      << "format: " << format;                          \
   EXPECT_EQ(expected_output, fmt::sprintf(make_positional(format), arg))
 
 TEST(PrintfTest, NoArgs) {
@@ -69,11 +71,10 @@ TEST(PrintfTest, Escape) {
 TEST(PrintfTest, PositionalArgs) {
   EXPECT_EQ("42", test_sprintf("%1$d", 42));
   EXPECT_EQ("before 42", test_sprintf("before %1$d", 42));
-  EXPECT_EQ("42 after", test_sprintf("%1$d after",42));
+  EXPECT_EQ("42 after", test_sprintf("%1$d after", 42));
   EXPECT_EQ("before 42 after", test_sprintf("before %1$d after", 42));
   EXPECT_EQ("answer = 42", test_sprintf("%1$s = %2$d", "answer", 42));
-  EXPECT_EQ("42 is the answer",
-      test_sprintf("%2$d is the %1$s", "answer", 42));
+  EXPECT_EQ("42 is the answer", test_sprintf("%2$d is the %1$s", "answer", 42));
   EXPECT_EQ("abracadabra", test_sprintf("%1$s%2$s%1$s", "abra", "cad"));
 }
 
@@ -82,46 +83,45 @@ TEST(PrintfTest, AutomaticArgIndexing) {
 }
 
 TEST(PrintfTest, NumberIsTooBigInArgIndex) {
-  EXPECT_THROW_MSG(test_sprintf(format("%{}$", BIG_NUM)),
-      format_error, "number is too big");
-  EXPECT_THROW_MSG(test_sprintf(format("%{}$d", BIG_NUM)),
-      format_error, "number is too big");
+  EXPECT_THROW_MSG(test_sprintf(format("%{}$", BIG_NUM)), format_error,
+                   "number is too big");
+  EXPECT_THROW_MSG(test_sprintf(format("%{}$d", BIG_NUM)), format_error,
+                   "number is too big");
 }
 
 TEST(PrintfTest, SwitchArgIndexing) {
-  EXPECT_THROW_MSG(test_sprintf("%1$d%", 1, 2),
-      format_error, "cannot switch from manual to automatic argument indexing");
+  EXPECT_THROW_MSG(test_sprintf("%1$d%", 1, 2), format_error,
+                   "cannot switch from manual to automatic argument indexing");
   EXPECT_THROW_MSG(test_sprintf(format("%1$d%{}d", BIG_NUM), 1, 2),
-      format_error, "number is too big");
-  EXPECT_THROW_MSG(test_sprintf("%1$d%d", 1, 2),
-      format_error, "cannot switch from manual to automatic argument indexing");
+                   format_error, "number is too big");
+  EXPECT_THROW_MSG(test_sprintf("%1$d%d", 1, 2), format_error,
+                   "cannot switch from manual to automatic argument indexing");
 
-  EXPECT_THROW_MSG(test_sprintf("%d%1$", 1, 2),
-      format_error, "cannot switch from automatic to manual argument indexing");
-  EXPECT_THROW_MSG(test_sprintf(format("%d%{}$d", BIG_NUM), 1, 2),
-      format_error, "number is too big");
-  EXPECT_THROW_MSG(test_sprintf("%d%1$d", 1, 2),
-      format_error, "cannot switch from automatic to manual argument indexing");
+  EXPECT_THROW_MSG(test_sprintf("%d%1$", 1, 2), format_error,
+                   "cannot switch from automatic to manual argument indexing");
+  EXPECT_THROW_MSG(test_sprintf(format("%d%{}$d", BIG_NUM), 1, 2), format_error,
+                   "number is too big");
+  EXPECT_THROW_MSG(test_sprintf("%d%1$d", 1, 2), format_error,
+                   "cannot switch from automatic to manual argument indexing");
 
   // Indexing errors override width errors.
   EXPECT_THROW_MSG(test_sprintf(format("%d%1${}d", BIG_NUM), 1, 2),
-      format_error, "number is too big");
+                   format_error, "number is too big");
   EXPECT_THROW_MSG(test_sprintf(format("%1$d%{}d", BIG_NUM), 1, 2),
-      format_error, "number is too big");
+                   format_error, "number is too big");
 }
 
 TEST(PrintfTest, InvalidArgIndex) {
   EXPECT_THROW_MSG(test_sprintf("%0$d", 42), format_error,
-      "argument index out of range");
+                   "argument not found");
   EXPECT_THROW_MSG(test_sprintf("%2$d", 42), format_error,
-      "argument index out of range");
-  EXPECT_THROW_MSG(test_sprintf(format("%{}$d", INT_MAX), 42),
-      format_error, "argument index out of range");
+                   "argument not found");
+  EXPECT_THROW_MSG(test_sprintf(format("%{}$d", INT_MAX), 42), format_error,
+                   "argument not found");
 
-  EXPECT_THROW_MSG(test_sprintf("%2$", 42),
-      format_error, "argument index out of range");
-  EXPECT_THROW_MSG(test_sprintf(format("%{}$d", BIG_NUM), 42),
-      format_error, "number is too big");
+  EXPECT_THROW_MSG(test_sprintf("%2$", 42), format_error, "argument not found");
+  EXPECT_THROW_MSG(test_sprintf(format("%{}$d", BIG_NUM), 42), format_error,
+                   "number is too big");
 }
 
 TEST(PrintfTest, DefaultAlignRight) {
@@ -139,8 +139,11 @@ TEST(PrintfTest, ZeroFlag) {
 
   EXPECT_PRINTF("+00042", "%00+6d", 42);
 
+  EXPECT_PRINTF("   42", "%05.d", 42);
+  EXPECT_PRINTF(" 0042", "%05.4d", 42);
+
   // '0' flag is ignored for non-numeric types.
-  EXPECT_PRINTF("0000x", "%05c", 'x');
+  EXPECT_PRINTF("    x", "%05c", 'x');
 }
 
 TEST(PrintfTest, PlusFlag) {
@@ -151,11 +154,38 @@ TEST(PrintfTest, PlusFlag) {
 
   // '+' flag is ignored for non-numeric types.
   EXPECT_PRINTF("x", "%+c", 'x');
+
+  // '+' flag wins over space flag
+  EXPECT_PRINTF("+42", "%+ d", 42);
+  EXPECT_PRINTF("-42", "%+ d", -42);
+  EXPECT_PRINTF("+42", "% +d", 42);
+  EXPECT_PRINTF("-42", "% +d", -42);
+  EXPECT_PRINTF("+0042", "% +05d", 42);
+  EXPECT_PRINTF("+0042", "%0+ 5d", 42);
+
+  // '+' flag and space flag are both ignored for non-numeric types.
+  EXPECT_PRINTF("x", "%+ c", 'x');
+  EXPECT_PRINTF("x", "% +c", 'x');
 }
 
 TEST(PrintfTest, MinusFlag) {
   EXPECT_PRINTF("abc  ", "%-5s", "abc");
   EXPECT_PRINTF("abc  ", "%0--5s", "abc");
+
+  EXPECT_PRINTF("7    ", "%-5d", 7);
+  EXPECT_PRINTF("97   ", "%-5hhi", 'a');
+  EXPECT_PRINTF("a    ", "%-5c", 'a');
+
+  // '0' flag is ignored if '-' flag is given
+  EXPECT_PRINTF("7    ", "%-05d", 7);
+  EXPECT_PRINTF("7    ", "%0-5d", 7);
+  EXPECT_PRINTF("a    ", "%-05c", 'a');
+  EXPECT_PRINTF("a    ", "%0-5c", 'a');
+  EXPECT_PRINTF("97   ", "%-05hhi", 'a');
+  EXPECT_PRINTF("97   ", "%0-5hhi", 'a');
+
+  // '-' and space flag don't interfere
+  EXPECT_PRINTF(" 42", "%- d", 42);
 }
 
 TEST(PrintfTest, SpaceFlag) {
@@ -175,8 +205,8 @@ TEST(PrintfTest, HashFlag) {
 
   EXPECT_PRINTF("0x42", "%#x", 0x42);
   EXPECT_PRINTF("0X42", "%#X", 0x42);
-  EXPECT_PRINTF(
-        fmt::format("0x{:x}", static_cast<unsigned>(-0x42)), "%#x", -0x42);
+  EXPECT_PRINTF(fmt::format("0x{:x}", static_cast<unsigned>(-0x42)), "%#x",
+                -0x42);
   EXPECT_PRINTF("0", "%#x", 0);
 
   EXPECT_PRINTF("0x0042", "%#06x", 0x42);
@@ -208,23 +238,22 @@ TEST(PrintfTest, Width) {
 
   // Width cannot be specified twice.
   EXPECT_THROW_MSG(test_sprintf("%5-5d", 42), format_error,
-      "invalid type specifier");
+                   "invalid type specifier");
 
-  EXPECT_THROW_MSG(test_sprintf(format("%{}d", BIG_NUM), 42),
-      format_error, "number is too big");
-  EXPECT_THROW_MSG(test_sprintf(format("%1${}d", BIG_NUM), 42),
-      format_error, "number is too big");
+  EXPECT_THROW_MSG(test_sprintf(format("%{}d", BIG_NUM), 42), format_error,
+                   "number is too big");
+  EXPECT_THROW_MSG(test_sprintf(format("%1${}d", BIG_NUM), 42), format_error,
+                   "number is too big");
 }
 
 TEST(PrintfTest, DynamicWidth) {
   EXPECT_EQ("   42", test_sprintf("%*d", 5, 42));
   EXPECT_EQ("42   ", test_sprintf("%*d", -5, 42));
   EXPECT_THROW_MSG(test_sprintf("%*d", 5.0, 42), format_error,
-      "width is not integer");
-  EXPECT_THROW_MSG(test_sprintf("%*d"), format_error,
-      "argument index out of range");
+                   "width is not integer");
+  EXPECT_THROW_MSG(test_sprintf("%*d"), format_error, "argument not found");
   EXPECT_THROW_MSG(test_sprintf("%*d", BIG_NUM, 42), format_error,
-      "number is too big");
+                   "number is too big");
 }
 
 TEST(PrintfTest, IntPrecision) {
@@ -253,12 +282,16 @@ TEST(PrintfTest, FloatPrecision) {
   safe_sprintf(buffer, "%.3e", 1234.5678);
   EXPECT_PRINTF(buffer, "%.3e", 1234.5678);
   EXPECT_PRINTF("1234.568", "%.3f", 1234.5678);
-  safe_sprintf(buffer, "%.3g", 1234.5678);
-  EXPECT_PRINTF(buffer, "%.3g", 1234.5678);
+  EXPECT_PRINTF("1.23e+03", "%.3g", 1234.5678);
   safe_sprintf(buffer, "%.3a", 1234.5678);
   EXPECT_PRINTF(buffer, "%.3a", 1234.5678);
 }
 
+TEST(PrintfTest, StringPrecision) {
+  char test[] = {'H', 'e', 'l', 'l', 'o'};
+  EXPECT_EQ(fmt::sprintf("%.4s", test), "Hell");
+}
+
 TEST(PrintfTest, IgnorePrecisionForNonNumericArg) {
   EXPECT_PRINTF("abc", "%.5s", "abc");
 }
@@ -267,24 +300,21 @@ TEST(PrintfTest, DynamicPrecision) {
   EXPECT_EQ("00042", test_sprintf("%.*d", 5, 42));
   EXPECT_EQ("42", test_sprintf("%.*d", -5, 42));
   EXPECT_THROW_MSG(test_sprintf("%.*d", 5.0, 42), format_error,
-      "precision is not integer");
-  EXPECT_THROW_MSG(test_sprintf("%.*d"), format_error,
-      "argument index out of range");
+                   "precision is not integer");
+  EXPECT_THROW_MSG(test_sprintf("%.*d"), format_error, "argument not found");
   EXPECT_THROW_MSG(test_sprintf("%.*d", BIG_NUM, 42), format_error,
-      "number is too big");
+                   "number is too big");
   if (sizeof(long long) != sizeof(int)) {
     long long prec = static_cast<long long>(INT_MIN) - 1;
     EXPECT_THROW_MSG(test_sprintf("%.*d", prec, 42), format_error,
-        "number is too big");
- }
+                     "number is too big");
+  }
 }
 
-template <typename T>
-struct make_signed { typedef T type; };
+template <typename T> struct make_signed { typedef T type; };
 
 #define SPECIALIZE_MAKE_SIGNED(T, S) \
-  template <> \
-  struct make_signed<T> { typedef S type; }
+  template <> struct make_signed<T> { typedef S type; }
 
 SPECIALIZE_MAKE_SIGNED(char, signed char);
 SPECIALIZE_MAKE_SIGNED(unsigned char, signed char);
@@ -295,24 +325,23 @@ SPECIALIZE_MAKE_SIGNED(unsigned long long, long long);
 
 // Test length format specifier ``length_spec``.
 template <typename T, typename U>
-void TestLength(const char *length_spec, U value) {
+void TestLength(const char* length_spec, U value) {
   long long signed_value = 0;
   unsigned long long unsigned_value = 0;
   // Apply integer promotion to the argument.
-  using std::numeric_limits;
-  unsigned long long max = numeric_limits<U>::max();
-  using fmt::internal::const_check;
-  if (const_check(max <= static_cast<unsigned>(numeric_limits<int>::max()))) {
+  unsigned long long max = max_value<U>();
+  using fmt::detail::const_check;
+  if (const_check(max <= static_cast<unsigned>(max_value<int>()))) {
     signed_value = static_cast<int>(value);
-    unsigned_value = static_cast<unsigned>(value);
-  } else if (const_check(max <= numeric_limits<unsigned>::max())) {
+    unsigned_value = static_cast<unsigned long long>(value);
+  } else if (const_check(max <= max_value<unsigned>())) {
     signed_value = static_cast<unsigned>(value);
-    unsigned_value = static_cast<unsigned>(value);
+    unsigned_value = static_cast<unsigned long long>(value);
   }
   if (sizeof(U) <= sizeof(int) && sizeof(int) < sizeof(T)) {
     signed_value = static_cast<long long>(value);
-    unsigned_value =
-        static_cast<typename std::make_unsigned<unsigned>::type>(value);
+    unsigned_value = static_cast<unsigned long long>(
+        static_cast<typename std::make_unsigned<unsigned>::type>(value));
   } else {
     signed_value = static_cast<typename make_signed<T>::type>(value);
     unsigned_value = static_cast<typename std::make_unsigned<T>::type>(value);
@@ -335,27 +364,28 @@ void TestLength(const char *length_spec, U value) {
   EXPECT_PRINTF(os.str(), fmt::format("%{}X", length_spec), value);
 }
 
-template <typename T>
-void TestLength(const char *length_spec) {
-  T min = std::numeric_limits<T>::min(), max = std::numeric_limits<T>::max();
+template <typename T> void TestLength(const char* length_spec) {
+  T min = std::numeric_limits<T>::min(), max = max_value<T>();
   TestLength<T>(length_spec, 42);
   TestLength<T>(length_spec, -42);
   TestLength<T>(length_spec, min);
   TestLength<T>(length_spec, max);
-  TestLength<T>(length_spec, static_cast<long long>(min) - 1);
-  unsigned long long long_long_max = std::numeric_limits<long long>::max();
+  long long long_long_min = std::numeric_limits<long long>::min();
+  if (static_cast<long long>(min) > long_long_min)
+    TestLength<T>(length_spec, static_cast<long long>(min) - 1);
+  unsigned long long long_long_max = max_value<long long>();
   if (static_cast<unsigned long long>(max) < long_long_max)
     TestLength<T>(length_spec, static_cast<long long>(max) + 1);
   TestLength<T>(length_spec, std::numeric_limits<short>::min());
-  TestLength<T>(length_spec, std::numeric_limits<unsigned short>::max());
+  TestLength<T>(length_spec, max_value<unsigned short>());
   TestLength<T>(length_spec, std::numeric_limits<int>::min());
-  TestLength<T>(length_spec, std::numeric_limits<int>::max());
+  TestLength<T>(length_spec, max_value<int>());
   TestLength<T>(length_spec, std::numeric_limits<unsigned>::min());
-  TestLength<T>(length_spec, std::numeric_limits<unsigned>::max());
+  TestLength<T>(length_spec, max_value<unsigned>());
   TestLength<T>(length_spec, std::numeric_limits<long long>::min());
-  TestLength<T>(length_spec, std::numeric_limits<long long>::max());
+  TestLength<T>(length_spec, max_value<long long>());
   TestLength<T>(length_spec, std::numeric_limits<unsigned long long>::min());
-  TestLength<T>(length_spec, std::numeric_limits<unsigned long long>::max());
+  TestLength<T>(length_spec, max_value<unsigned long long>());
 }
 
 TEST(PrintfTest, Length) {
@@ -369,11 +399,11 @@ TEST(PrintfTest, Length) {
   TestLength<long long>("ll");
   TestLength<unsigned long long>("ll");
   TestLength<intmax_t>("j");
-  TestLength<std::size_t>("z");
+  TestLength<size_t>("z");
   TestLength<std::ptrdiff_t>("t");
-  long double max = std::numeric_limits<long double>::max();
-  EXPECT_PRINTF(fmt::format("{}", max), "%g", max);
-  EXPECT_PRINTF(fmt::format("{}", max), "%Lg", max);
+  long double max = max_value<long double>();
+  EXPECT_PRINTF(fmt::format("{:.6}", max), "%g", max);
+  EXPECT_PRINTF(fmt::format("{:.6}", max), "%Lg", max);
 }
 
 TEST(PrintfTest, Bool) {
@@ -394,7 +424,7 @@ TEST(PrintfTest, Int) {
 TEST(PrintfTest, long_long) {
   // fmt::printf allows passing long long arguments to %d without length
   // specifiers.
-  long long max = std::numeric_limits<long long>::max();
+  long long max = max_value<long long>();
   EXPECT_PRINTF(fmt::format("{}", max), "%d", max);
 }
 
@@ -411,6 +441,9 @@ TEST(PrintfTest, Float) {
   EXPECT_PRINTF(buffer, "%E", 392.65);
   EXPECT_PRINTF("392.65", "%g", 392.65);
   EXPECT_PRINTF("392.65", "%G", 392.65);
+  EXPECT_PRINTF("392", "%g", 392.0);
+  EXPECT_PRINTF("392", "%G", 392.0);
+  EXPECT_PRINTF("4.56e-07", "%g", 0.000000456);
   safe_sprintf(buffer, "%a", -392.65);
   EXPECT_EQ(buffer, format("{:a}", -392.65));
   safe_sprintf(buffer, "%A", -392.65);
@@ -428,44 +461,50 @@ TEST(PrintfTest, Inf) {
 
 TEST(PrintfTest, Char) {
   EXPECT_PRINTF("x", "%c", 'x');
-  int max = std::numeric_limits<int>::max();
+  int max = max_value<int>();
   EXPECT_PRINTF(fmt::format("{}", static_cast<char>(max)), "%c", max);
-  //EXPECT_PRINTF("x", "%lc", L'x');
+  // EXPECT_PRINTF("x", "%lc", L'x');
   EXPECT_PRINTF(L"x", L"%c", L'x');
   EXPECT_PRINTF(fmt::format(L"{}", static_cast<wchar_t>(max)), L"%c", max);
 }
 
 TEST(PrintfTest, String) {
   EXPECT_PRINTF("abc", "%s", "abc");
-  const char *null_str = FMT_NULL;
+  const char* null_str = nullptr;
   EXPECT_PRINTF("(null)", "%s", null_str);
   EXPECT_PRINTF("    (null)", "%10s", null_str);
   EXPECT_PRINTF(L"abc", L"%s", L"abc");
-  const wchar_t *null_wstr = FMT_NULL;
+  const wchar_t* null_wstr = nullptr;
   EXPECT_PRINTF(L"(null)", L"%s", null_wstr);
   EXPECT_PRINTF(L"    (null)", L"%10s", null_wstr);
 }
 
+TEST(PrintfTest, UCharString) {
+  unsigned char str[] = "test";
+  unsigned char* pstr = str;
+  EXPECT_EQ("test", fmt::sprintf("%s", pstr));
+}
+
 TEST(PrintfTest, Pointer) {
   int n;
-  void *p = &n;
+  void* p = &n;
   EXPECT_PRINTF(fmt::format("{}", p), "%p", p);
-  p = FMT_NULL;
+  p = nullptr;
   EXPECT_PRINTF("(nil)", "%p", p);
   EXPECT_PRINTF("     (nil)", "%10p", p);
-  const char *s = "test";
+  const char* s = "test";
   EXPECT_PRINTF(fmt::format("{:p}", s), "%p", s);
-  const char *null_str = FMT_NULL;
+  const char* null_str = nullptr;
   EXPECT_PRINTF("(nil)", "%p", null_str);
 
   p = &n;
   EXPECT_PRINTF(fmt::format(L"{}", p), L"%p", p);
-  p = FMT_NULL;
+  p = nullptr;
   EXPECT_PRINTF(L"(nil)", L"%p", p);
   EXPECT_PRINTF(L"     (nil)", L"%10p", p);
-  const wchar_t *w = L"test";
+  const wchar_t* w = L"test";
   EXPECT_PRINTF(fmt::format(L"{:p}", w), L"%p", w);
-  const wchar_t *null_wstr = FMT_NULL;
+  const wchar_t* null_wstr = nullptr;
   EXPECT_PRINTF(L"(nil)", L"%p", null_wstr);
 }
 
@@ -473,16 +512,18 @@ TEST(PrintfTest, Location) {
   // TODO: test %n
 }
 
-enum E { A = 42 };
+enum test_enum { answer = 42 };
 
 TEST(PrintfTest, Enum) {
-  EXPECT_PRINTF("42", "%d", A);
+  EXPECT_PRINTF("42", "%d", answer);
+  volatile test_enum volatile_enum = answer;
+  EXPECT_PRINTF("42", "%d", volatile_enum);
 }
 
-#if FMT_USE_FILE_DESCRIPTORS
+#if FMT_USE_FCNTL
 TEST(PrintfTest, Examples) {
-  const char *weekday = "Thursday";
-  const char *month = "August";
+  const char* weekday = "Thursday";
+  const char* month = "August";
   int day = 21;
   EXPECT_WRITE(stdout, fmt::printf("%1$s, %3$d %2$s", weekday, month, day),
                "Thursday, 21 August");
@@ -496,9 +537,7 @@ TEST(PrintfTest, PrintfError) {
 }
 #endif
 
-TEST(PrintfTest, WideString) {
-  EXPECT_EQ(L"abc", fmt::sprintf(L"%s", L"abc"));
-}
+TEST(PrintfTest, WideString) { EXPECT_EQ(L"abc", fmt::sprintf(L"%s", L"abc")); }
 
 TEST(PrintfTest, PrintfCustom) {
   EXPECT_EQ("abc", test_sprintf("%s", TestString("abc")));
@@ -520,7 +559,7 @@ TEST(PrintfTest, VPrintf) {
   EXPECT_WRITE(stdout, fmt::vfprintf(std::cout, "%d", args), "42");
 }
 
-template<typename... Args>
+template <typename... Args>
 void check_format_string_regression(fmt::string_view s, const Args&... args) {
   fmt::sprintf(s, args...);
 }
@@ -529,41 +568,61 @@ TEST(PrintfTest, CheckFormatStringRegression) {
   check_format_string_regression("%c%s", 'x', "");
 }
 
+TEST(PrintfTest, FixedLargeExponent) {
+  EXPECT_EQ("1000000000000000000000", fmt::sprintf("%.*f", -13, 1e21));
+}
+
 TEST(PrintfTest, VSPrintfMakeArgsExample) {
-  fmt::format_arg_store<fmt::printf_context, int, const char *> as{
-      42, "something"};
+  fmt::format_arg_store<fmt::printf_context, int, const char*> as{42,
+                                                                  "something"};
   fmt::basic_format_args<fmt::printf_context> args(as);
-  EXPECT_EQ(
-      "[42] something happened", fmt::vsprintf("[%d] %s happened", args));
+  EXPECT_EQ("[42] something happened", fmt::vsprintf("[%d] %s happened", args));
   auto as2 = fmt::make_printf_args(42, "something");
   fmt::basic_format_args<fmt::printf_context> args2(as2);
-  EXPECT_EQ(
-      "[42] something happened", fmt::vsprintf("[%d] %s happened", args2));
-  //the older gcc versions can't cast the return value
-#if !defined(__GNUC__) || (__GNUC__ > 4) 
-  EXPECT_EQ(
-      "[42] something happened",
-      fmt::vsprintf(
-          "[%d] %s happened", fmt::make_printf_args(42, "something")));
+  EXPECT_EQ("[42] something happened",
+            fmt::vsprintf("[%d] %s happened", args2));
+  // The older gcc versions can't cast the return value.
+#if !defined(__GNUC__) || (__GNUC__ > 4)
+  EXPECT_EQ("[42] something happened",
+            fmt::vsprintf("[%d] %s happened",
+                          {fmt::make_printf_args(42, "something")}));
 #endif
 }
 
 TEST(PrintfTest, VSPrintfMakeWArgsExample) {
-  fmt::format_arg_store<fmt::wprintf_context, int, const wchar_t *> as{
-     42, L"something"};
+  fmt::format_arg_store<fmt::wprintf_context, int, const wchar_t*> as{
+      42, L"something"};
   fmt::basic_format_args<fmt::wprintf_context> args(as);
-  EXPECT_EQ(
-     L"[42] something happened",
-     fmt::vsprintf(L"[%d] %s happened", args));
-  auto  as2 = fmt::make_wprintf_args(42, L"something");
+  EXPECT_EQ(L"[42] something happened",
+            fmt::vsprintf(L"[%d] %s happened", args));
+  auto as2 = fmt::make_wprintf_args(42, L"something");
   fmt::basic_format_args<fmt::wprintf_context> args2(as2);
-  EXPECT_EQ(
-      L"[42] something happened", fmt::vsprintf(L"[%d] %s happened", args2));
+  EXPECT_EQ(L"[42] something happened",
+            fmt::vsprintf(L"[%d] %s happened", args2));
   // the older gcc versions can't cast the return value
 #if !defined(__GNUC__) || (__GNUC__ > 4)
-  EXPECT_EQ(
-      L"[42] something happened",
-      fmt::vsprintf(
-          L"[%d] %s happened", fmt::make_wprintf_args(42, L"something")));
+  EXPECT_EQ(L"[42] something happened",
+            fmt::vsprintf(L"[%d] %s happened",
+                          {fmt::make_wprintf_args(42, L"something")}));
 #endif
 }
+
+TEST(PrintfTest, PrintfDetermineOutputSize) {
+  using backit = std::back_insert_iterator<std::vector<char>>;
+  using truncated_printf_context =
+      fmt::basic_printf_context<fmt::detail::truncating_iterator<backit>, char>;
+
+  auto v = std::vector<char>{};
+  auto it = std::back_inserter(v);
+
+  const auto format_string = "%s";
+  const auto format_arg = "Hello";
+  const auto expected_size = fmt::sprintf(format_string, format_arg).size();
+
+  EXPECT_EQ((truncated_printf_context(
+                 fmt::detail::truncating_iterator<backit>(it, 0), format_string,
+                 fmt::make_format_args<truncated_printf_context>(format_arg))
+                 .format()
+                 .count()),
+            expected_size);
+}

test/ranges-test.cc

@@ -9,17 +9,18 @@
 // All Rights Reserved
 // {fmt} support for ranges, containers and types tuple interface.
 
-/// Check if  'if constexpr' is supported.
+#include "fmt/ranges.h"
+
+#include "gtest.h"
+
+// Check if  'if constexpr' is supported.
 #if (__cplusplus > 201402L) || \
     (defined(_MSVC_LANG) && _MSVC_LANG > 201402L && _MSC_VER >= 1910)
 
-#include "fmt/ranges.h"
-#include "gtest.h"
-
-#include <vector>
-#include <array>
-#include <map>
-#include <string>
+#  include <array>
+#  include <map>
+#  include <string>
+#  include <vector>
 
 TEST(RangesTest, FormatVector) {
   std::vector<int32_t> iv{1, 2, 3, 5, 7, 11};
@@ -39,21 +40,46 @@ TEST(RangesTest, FormatMap) {
 }
 
 TEST(RangesTest, FormatPair) {
-  std::pair<int64_t, float> pa1{42, 3.14159265358979f};
-  EXPECT_EQ("(42, 3.14159)", fmt::format("{}", pa1));
+  std::pair<int64_t, float> pa1{42, 1.5f};
+  EXPECT_EQ("(42, 1.5)", fmt::format("{}", pa1));
 }
 
 TEST(RangesTest, FormatTuple) {
-  std::tuple<int64_t, float, std::string, char> tu1{42, 3.14159265358979f,
-                                              "this is tuple", 'i'};
-  EXPECT_EQ("(42, 3.14159, \"this is tuple\", 'i')", fmt::format("{}", tu1));
+  std::tuple<int64_t, float, std::string, char> t{42, 1.5f, "this is tuple",
+                                                  'i'};
+  EXPECT_EQ("(42, 1.5, \"this is tuple\", 'i')", fmt::format("{}", t));
+  EXPECT_EQ("()", fmt::format("{}", std::tuple<>()));
+}
+
+TEST(RangesTest, JoinTuple) {
+  // Value tuple args
+  std::tuple<char, int, float> t1 = std::make_tuple('a', 1, 2.0f);
+  EXPECT_EQ("(a, 1, 2)", fmt::format("({})", fmt::join(t1, ", ")));
+
+  // Testing lvalue tuple args
+  int x = 4;
+  std::tuple<char, int&> t2{'b', x};
+  EXPECT_EQ("b + 4", fmt::format("{}", fmt::join(t2, " + ")));
+
+  // Empty tuple
+  std::tuple<> t3;
+  EXPECT_EQ("", fmt::format("{}", fmt::join(t3, "|")));
+
+  // Single element tuple
+  std::tuple<float> t4{4.0f};
+  EXPECT_EQ("4", fmt::format("{}", fmt::join(t4, "/")));
+}
+
+TEST(RangesTest, JoinInitializerList) {
+  EXPECT_EQ("1, 2, 3", fmt::format("{}", fmt::join({1, 2, 3}, ", ")));
+  EXPECT_EQ("fmt rocks !",
+            fmt::format("{}", fmt::join({"fmt", "rocks", "!"}, " ")));
 }
 
 struct my_struct {
   int32_t i;
   std::string str;  // can throw
-  template <std::size_t N>
-  decltype(auto) get() const noexcept {
+  template <size_t N> decltype(auto) get() const noexcept {
     if constexpr (N == 0)
       return i;
     else if constexpr (N == 1)
@@ -61,18 +87,15 @@ struct my_struct {
   }
 };
 
-template <std::size_t N>
-decltype(auto) get(const my_struct& s) noexcept {
+template <size_t N> decltype(auto) get(const my_struct& s) noexcept {
   return s.get<N>();
 }
 
 namespace std {
 
-template <>
-struct tuple_size<my_struct> : std::integral_constant<std::size_t, 2> {};
+template <> struct tuple_size<my_struct> : std::integral_constant<size_t, 2> {};
 
-template <std::size_t N>
-struct tuple_element<N, my_struct> {
+template <size_t N> struct tuple_element<N, my_struct> {
   using type = decltype(std::declval<my_struct>().get<N>());
 };
 
@@ -83,5 +106,98 @@ TEST(RangesTest, FormatStruct) {
   EXPECT_EQ("(13, \"my struct\")", fmt::format("{}", mst));
 }
 
+TEST(RangesTest, FormatTo) {
+  char buf[10];
+  auto end = fmt::format_to(buf, "{}", std::vector{1, 2, 3});
+  *end = '\0';
+  EXPECT_STREQ(buf, "{1, 2, 3}");
+}
+
+struct path_like {
+  const path_like* begin() const;
+  const path_like* end() const;
+
+  operator std::string() const;
+};
+
+TEST(RangesTest, PathLike) {
+  EXPECT_FALSE((fmt::is_range<path_like, char>::value));
+}
+
 #endif  // (__cplusplus > 201402L) || (defined(_MSVC_LANG) && _MSVC_LANG >
         // 201402L && _MSC_VER >= 1910)
+
+#ifdef FMT_USE_STRING_VIEW
+struct string_like {
+  const char* begin();
+  const char* end();
+  explicit operator fmt::string_view() const { return "foo"; }
+  explicit operator std::string_view() const { return "foo"; }
+};
+
+TEST(RangesTest, FormatStringLike) {
+  EXPECT_EQ("foo", fmt::format("{}", string_like()));
+}
+#endif  // FMT_USE_STRING_VIEW
+
+struct zstring_sentinel {};
+
+bool operator==(const char* p, zstring_sentinel) { return *p == '\0'; }
+bool operator!=(const char* p, zstring_sentinel) { return *p != '\0'; }
+
+struct zstring {
+  const char* p;
+  const char* begin() const { return p; }
+  zstring_sentinel end() const { return {}; }
+};
+
+TEST(RangesTest, JoinSentinel) {
+  zstring hello{"hello"};
+  EXPECT_EQ("{'h', 'e', 'l', 'l', 'o'}", fmt::format("{}", hello));
+  EXPECT_EQ("h_e_l_l_o", fmt::format("{}", fmt::join(hello, "_")));
+}
+
+// A range that provides non-const only begin()/end() to test fmt::join handles
+// that
+//
+// Some ranges (eg those produced by range-v3's views::filter()) can cache
+// information during iteration so they only provide non-const begin()/end().
+template <typename T> class non_const_only_range {
+ private:
+  std::vector<T> vec;
+
+ public:
+  using const_iterator = typename ::std::vector<T>::const_iterator;
+
+  template <typename... Args>
+  explicit non_const_only_range(Args&&... args)
+      : vec(::std::forward<Args>(args)...) {}
+
+  const_iterator begin() { return vec.begin(); }
+  const_iterator end() { return vec.end(); }
+};
+
+TEST(RangesTest, JoinRange) {
+  non_const_only_range<int> x(3u, 0);
+  EXPECT_EQ("0,0,0", fmt::format("{}", fmt::join(x, ",")));
+  EXPECT_EQ(
+      "0,0,0",
+      fmt::format("{}", fmt::join(non_const_only_range<int>(3u, 0), ",")));
+
+  std::vector<int> y(3u, 0);
+  EXPECT_EQ("0,0,0", fmt::format("{}", fmt::join(y, ",")));
+  EXPECT_EQ("0,0,0",
+            fmt::format("{}", fmt::join(std::vector<int>(3u, 0), ",")));
+
+  const std::vector<int> z(3u, 0);
+  EXPECT_EQ("0,0,0", fmt::format("{}", fmt::join(z, ",")));
+}
+
+#if !FMT_MSC_VER || FMT_MSC_VER >= 1927
+struct unformattable {};
+
+TEST(RangesTest, UnformattableRange) {
+  EXPECT_FALSE((fmt::has_formatter<std::vector<unformattable>,
+                                   fmt::format_context>::value));
+}
+#endif

test/scan-test.cc

@@ -0,0 +1,116 @@
+// Formatting library for C++ - scanning API test
+//
+// Copyright (c) 2019 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include "scan.h"
+
+#include <time.h>
+
+#include <climits>
+
+#include "gmock.h"
+#include "gtest-extra.h"
+
+TEST(ScanTest, ReadText) {
+  fmt::string_view s = "foo";
+  auto end = fmt::scan(s, "foo");
+  EXPECT_EQ(end, s.end());
+  EXPECT_THROW_MSG(fmt::scan("fob", "foo"), fmt::format_error, "invalid input");
+}
+
+TEST(ScanTest, ReadInt) {
+  int n = 0;
+  fmt::scan("42", "{}", n);
+  EXPECT_EQ(n, 42);
+  fmt::scan("-42", "{}", n);
+  EXPECT_EQ(n, -42);
+}
+
+TEST(ScanTest, ReadLongLong) {
+  long long n = 0;
+  fmt::scan("42", "{}", n);
+  EXPECT_EQ(n, 42);
+  fmt::scan("-42", "{}", n);
+  EXPECT_EQ(n, -42);
+}
+
+TEST(ScanTest, ReadUInt) {
+  unsigned n = 0;
+  fmt::scan("42", "{}", n);
+  EXPECT_EQ(n, 42);
+  EXPECT_THROW_MSG(fmt::scan("-42", "{}", n), fmt::format_error,
+                   "invalid input");
+}
+
+TEST(ScanTest, ReadULongLong) {
+  unsigned long long n = 0;
+  fmt::scan("42", "{}", n);
+  EXPECT_EQ(n, 42);
+  EXPECT_THROW_MSG(fmt::scan("-42", "{}", n), fmt::format_error,
+                   "invalid input");
+}
+
+TEST(ScanTest, ReadString) {
+  std::string s;
+  fmt::scan("foo", "{}", s);
+  EXPECT_EQ(s, "foo");
+}
+
+TEST(ScanTest, ReadStringView) {
+  fmt::string_view s;
+  fmt::scan("foo", "{}", s);
+  EXPECT_EQ(s, "foo");
+}
+
+#ifndef _WIN32
+namespace fmt {
+template <> struct scanner<tm> {
+  std::string format;
+
+  scan_parse_context::iterator parse(scan_parse_context& ctx) {
+    auto it = ctx.begin();
+    if (it != ctx.end() && *it == ':') ++it;
+    auto end = it;
+    while (end != ctx.end() && *end != '}') ++end;
+    format.reserve(detail::to_unsigned(end - it + 1));
+    format.append(it, end);
+    format.push_back('\0');
+    return end;
+  }
+
+  template <class ScanContext>
+  typename ScanContext::iterator scan(tm& t, ScanContext& ctx) {
+    auto result = strptime(ctx.begin(), format.c_str(), &t);
+    if (!result) throw format_error("failed to parse time");
+    return result;
+  }
+};
+}  // namespace fmt
+
+TEST(ScanTest, ReadCustom) {
+  const char* input = "Date: 1985-10-25";
+  auto t = tm();
+  fmt::scan(input, "Date: {0:%Y-%m-%d}", t);
+  EXPECT_EQ(t.tm_year, 85);
+  EXPECT_EQ(t.tm_mon, 9);
+  EXPECT_EQ(t.tm_mday, 25);
+}
+#endif
+
+TEST(ScanTest, InvalidFormat) {
+  EXPECT_THROW_MSG(fmt::scan("", "{}"), fmt::format_error,
+                   "argument index out of range");
+  EXPECT_THROW_MSG(fmt::scan("", "{"), fmt::format_error,
+                   "invalid format string");
+}
+
+TEST(ScanTest, Example) {
+  std::string key;
+  int value;
+  fmt::scan("answer = 42", "{} = {}", key, value);
+  EXPECT_EQ(key, "answer");
+  EXPECT_EQ(value, 42);
+}

test/scan.h

@@ -0,0 +1,238 @@
+// Formatting library for C++ - scanning API proof of concept
+//
+// Copyright (c) 2019 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include <array>
+#include <cassert>
+#include <climits>
+
+#include "fmt/format.h"
+
+FMT_BEGIN_NAMESPACE
+template <typename T, typename Char = char> struct scanner {
+  // A deleted default constructor indicates a disabled scanner.
+  scanner() = delete;
+};
+
+class scan_parse_context {
+ private:
+  string_view format_;
+
+ public:
+  using iterator = string_view::iterator;
+
+  explicit FMT_CONSTEXPR scan_parse_context(string_view format)
+      : format_(format) {}
+
+  FMT_CONSTEXPR iterator begin() const { return format_.begin(); }
+  FMT_CONSTEXPR iterator end() const { return format_.end(); }
+
+  void advance_to(iterator it) {
+    format_.remove_prefix(detail::to_unsigned(it - begin()));
+  }
+};
+
+struct scan_context {
+ private:
+  string_view input_;
+
+ public:
+  using iterator = const char*;
+
+  explicit scan_context(string_view input) : input_(input) {}
+
+  iterator begin() const { return input_.data(); }
+  iterator end() const { return begin() + input_.size(); }
+
+  void advance_to(iterator it) {
+    input_.remove_prefix(detail::to_unsigned(it - begin()));
+  }
+};
+
+namespace detail {
+enum class scan_type {
+  none_type,
+  int_type,
+  uint_type,
+  long_long_type,
+  ulong_long_type,
+  string_type,
+  string_view_type,
+  custom_type
+};
+
+struct custom_scan_arg {
+  void* value;
+  void (*scan)(void* arg, scan_parse_context& parse_ctx, scan_context& ctx);
+};
+
+class scan_arg {
+ public:
+  scan_type type;
+  union {
+    int* int_value;
+    unsigned* uint_value;
+    long long* long_long_value;
+    unsigned long long* ulong_long_value;
+    std::string* string;
+    fmt::string_view* string_view;
+    custom_scan_arg custom;
+    // TODO: more types
+  };
+
+  scan_arg() : type(scan_type::none_type) {}
+  scan_arg(int& value) : type(scan_type::int_type), int_value(&value) {}
+  scan_arg(unsigned& value) : type(scan_type::uint_type), uint_value(&value) {}
+  scan_arg(long long& value)
+      : type(scan_type::long_long_type), long_long_value(&value) {}
+  scan_arg(unsigned long long& value)
+      : type(scan_type::ulong_long_type), ulong_long_value(&value) {}
+  scan_arg(std::string& value) : type(scan_type::string_type), string(&value) {}
+  scan_arg(fmt::string_view& value)
+      : type(scan_type::string_view_type), string_view(&value) {}
+  template <typename T> scan_arg(T& value) : type(scan_type::custom_type) {
+    custom.value = &value;
+    custom.scan = scan_custom_arg<T>;
+  }
+
+ private:
+  template <typename T>
+  static void scan_custom_arg(void* arg, scan_parse_context& parse_ctx,
+                              scan_context& ctx) {
+    scanner<T> s;
+    parse_ctx.advance_to(s.parse(parse_ctx));
+    ctx.advance_to(s.scan(*static_cast<T*>(arg), ctx));
+  }
+};
+}  // namespace detail
+
+struct scan_args {
+  int size;
+  const detail::scan_arg* data;
+
+  template <size_t N>
+  scan_args(const std::array<detail::scan_arg, N>& store)
+      : size(N), data(store.data()) {
+    static_assert(N < INT_MAX, "too many arguments");
+  }
+};
+
+namespace detail {
+
+struct scan_handler : error_handler {
+ private:
+  scan_parse_context parse_ctx_;
+  scan_context scan_ctx_;
+  scan_args args_;
+  int next_arg_id_;
+  scan_arg arg_;
+
+  template <typename T = unsigned> T read_uint() {
+    T value = 0;
+    auto it = scan_ctx_.begin(), end = scan_ctx_.end();
+    while (it != end) {
+      char c = *it++;
+      if (c < '0' || c > '9') on_error("invalid input");
+      // TODO: check overflow
+      value = value * 10 + static_cast<unsigned>(c - '0');
+    }
+    scan_ctx_.advance_to(it);
+    return value;
+  }
+
+  template <typename T = int> T read_int() {
+    auto it = scan_ctx_.begin(), end = scan_ctx_.end();
+    bool negative = it != end && *it == '-';
+    if (negative) ++it;
+    scan_ctx_.advance_to(it);
+    const auto value = read_uint<typename std::make_unsigned<T>::type>();
+    if (negative) return -static_cast<T>(value);
+    return static_cast<T>(value);
+  }
+
+ public:
+  scan_handler(string_view format, string_view input, scan_args args)
+      : parse_ctx_(format), scan_ctx_(input), args_(args), next_arg_id_(0) {}
+
+  const char* pos() const { return scan_ctx_.begin(); }
+
+  void on_text(const char* begin, const char* end) {
+    auto size = to_unsigned(end - begin);
+    auto it = scan_ctx_.begin();
+    if (it + size > scan_ctx_.end() ||
+        !std::equal(begin, end, make_checked(it, size))) {
+      on_error("invalid input");
+    }
+    scan_ctx_.advance_to(it + size);
+  }
+
+  int on_arg_id() { return on_arg_id(next_arg_id_++); }
+  int on_arg_id(int id) {
+    if (id >= args_.size) on_error("argument index out of range");
+    arg_ = args_.data[id];
+    return id;
+  }
+  int on_arg_id(string_view) { return on_error("invalid format"), 0; }
+
+  void on_replacement_field(int, const char*) {
+    auto it = scan_ctx_.begin(), end = scan_ctx_.end();
+    switch (arg_.type) {
+    case scan_type::int_type:
+      *arg_.int_value = read_int();
+      break;
+    case scan_type::uint_type:
+      *arg_.uint_value = read_uint();
+      break;
+    case scan_type::long_long_type:
+      *arg_.long_long_value = read_int<long long>();
+      break;
+    case scan_type::ulong_long_type:
+      *arg_.ulong_long_value = read_uint<unsigned long long>();
+      break;
+    case scan_type::string_type:
+      while (it != end && *it != ' ') arg_.string->push_back(*it++);
+      scan_ctx_.advance_to(it);
+      break;
+    case scan_type::string_view_type: {
+      auto s = it;
+      while (it != end && *it != ' ') ++it;
+      *arg_.string_view = fmt::string_view(s, to_unsigned(it - s));
+      scan_ctx_.advance_to(it);
+      break;
+    }
+    case scan_type::none_type:
+    case scan_type::custom_type:
+      assert(false);
+    }
+  }
+
+  const char* on_format_specs(int, const char* begin, const char*) {
+    if (arg_.type != scan_type::custom_type) return begin;
+    parse_ctx_.advance_to(begin);
+    arg_.custom.scan(arg_.custom.value, parse_ctx_, scan_ctx_);
+    return parse_ctx_.begin();
+  }
+};
+}  // namespace detail
+
+template <typename... Args>
+std::array<detail::scan_arg, sizeof...(Args)> make_scan_args(Args&... args) {
+  return {{args...}};
+}
+
+string_view::iterator vscan(string_view input, string_view format_str,
+                            scan_args args) {
+  detail::scan_handler h(format_str, input, args);
+  detail::parse_format_string<false>(format_str, h);
+  return input.begin() + (h.pos() - &*input.begin());
+}
+
+template <typename... Args>
+string_view::iterator scan(string_view input, string_view format_str,
+                           Args&... args) {
+  return vscan(input, format_str, make_scan_args(args...));
+}
+FMT_END_NAMESPACE

test/std-format-test.cc

@@ -0,0 +1,157 @@
+#include <format>
+
+#include "gtest.h"
+
+TEST(StdFormatTest, Escaping) {
+  using namespace std;
+  string s = format("{0}-{{", 8);  // s == "8-{"
+  EXPECT_EQ(s, "8-{");
+}
+
+TEST(StdFormatTest, Indexing) {
+  using namespace std;
+  string s0 = format("{} to {}", "a", "b");    // OK: automatic indexing
+  string s1 = format("{1} to {0}", "a", "b");  // OK: manual indexing
+  EXPECT_EQ(s0, "a to b");
+  EXPECT_EQ(s1, "b to a");
+  // Error: mixing automatic and manual indexing
+  EXPECT_THROW(string s2 = format("{0} to {}", "a", "b"), std::format_error);
+  // Error: mixing automatic and manual indexing
+  EXPECT_THROW(string s3 = format("{} to {1}", "a", "b"), std::format_error);
+}
+
+TEST(StdFormatTest, Alignment) {
+  using namespace std;
+  char c = 120;
+  string s0 = format("{:6}", 42);     // s0 == "    42"
+  string s1 = format("{:6}", 'x');    // s1 == "x     "
+  string s2 = format("{:*<6}", 'x');  // s2 == "x*****"
+  string s3 = format("{:*>6}", 'x');  // s3 == "*****x"
+  string s4 = format("{:*^6}", 'x');  // s4 == "**x***"
+  // Error: '=' with charT and no integer presentation type
+  EXPECT_THROW(string s5 = format("{:=6}", 'x'), std::format_error);
+  string s6 = format("{:6d}", c);    // s6 == "   120"
+  string s7 = format("{:6}", true);  // s9 == "true  "
+  EXPECT_EQ(s0, "    42");
+  EXPECT_EQ(s1, "x     ");
+  EXPECT_EQ(s2, "x*****");
+  EXPECT_EQ(s3, "*****x");
+  EXPECT_EQ(s4, "**x***");
+  EXPECT_EQ(s6, "   120");
+  EXPECT_EQ(s7, "true  ");
+}
+
+TEST(StdFormatTest, Float) {
+  using namespace std;
+  double inf = numeric_limits<double>::infinity();
+  double nan = numeric_limits<double>::quiet_NaN();
+  string s0 = format("{0:} {0:+} {0:-} {0: }", 1);   // s0 == "1 +1 1  1"
+  string s1 = format("{0:} {0:+} {0:-} {0: }", -1);  // s1 == "-1 -1 -1 -1"
+  string s2 =
+      format("{0:} {0:+} {0:-} {0: }", inf);  // s2 == "inf +inf inf  inf"
+  string s3 =
+      format("{0:} {0:+} {0:-} {0: }", nan);  // s3 == "nan +nan nan  nan"
+  EXPECT_EQ(s0, "1 +1 1  1");
+  EXPECT_EQ(s1, "-1 -1 -1 -1");
+  EXPECT_EQ(s2, "inf +inf inf  inf");
+  EXPECT_EQ(s3, "nan +nan nan  nan");
+}
+
+TEST(StdFormatTest, Int) {
+  using namespace std;
+  string s0 = format("{}", 42);                       // s0 == "42"
+  string s1 = format("{0:b} {0:d} {0:o} {0:x}", 42);  // s1 == "101010 42 52 2a"
+  string s2 = format("{0:#x} {0:#X}", 42);            // s2 == "0x2a 0X2A"
+  string s3 = format("{:L}", 1234);  // s3 == "1234" (depends on the locale)
+  EXPECT_EQ(s0, "42");
+  EXPECT_EQ(s1, "101010 42 52 2a");
+  EXPECT_EQ(s2, "0x2a 0X2A");
+  EXPECT_EQ(s3, "1234");
+}
+
+#include <format>
+
+enum color { red, green, blue };
+
+const char* color_names[] = {"red", "green", "blue"};
+
+template <> struct std::formatter<color> : std::formatter<const char*> {
+  auto format(color c, format_context& ctx) {
+    return formatter<const char*>::format(color_names[c], ctx);
+  }
+};
+
+struct err {};
+
+TEST(StdFormatTest, Formatter) {
+  std::string s0 = std::format("{}", 42);  // OK: library-provided formatter
+  // std::string s1 = std::format("{}", L"foo"); // Ill-formed: disabled
+  // formatter
+  std::string s2 = std::format("{}", red);  // OK: user-provided formatter
+  // std::string s3 = std::format("{}", err{});  // Ill-formed: disabled
+  // formatter
+  EXPECT_EQ(s0, "42");
+  EXPECT_EQ(s2, "red");
+}
+
+struct S {
+  int value;
+};
+
+template <> struct std::formatter<S> {
+  size_t width_arg_id = 0;
+
+  // Parses a width argument id in the format { <digit> }.
+  constexpr auto parse(format_parse_context& ctx) {
+    auto iter = ctx.begin();
+    // auto get_char = [&]() { return iter != ctx.end() ? *iter : 0; };
+    auto get_char = [&]() { return iter != ctx.end() ? *iter : '\0'; };
+    if (get_char() != '{') return iter;
+    ++iter;
+    char c = get_char();
+    if (!isdigit(c) || (++iter, get_char()) != '}')
+      throw format_error("invalid format");
+    width_arg_id = c - '0';
+    ctx.check_arg_id(width_arg_id);
+    return ++iter;
+  }
+
+  // Formats S with width given by the argument width_arg_id.
+  auto format(S s, format_context& ctx) {
+    int width = visit_format_arg(
+        [](auto value) -> int {
+          using type = decltype(value);
+          if constexpr (!is_integral_v<type> || is_same_v<type, bool>)
+            throw format_error("width is not integral");
+          // else if (value < 0 || value > numeric_limits<int>::max())
+          else if (fmt::detail::is_negative(value) ||
+                   value > numeric_limits<int>::max())
+            throw format_error("invalid width");
+          else
+            return static_cast<int>(value);
+        },
+        ctx.arg(width_arg_id));
+    return format_to(ctx.out(), "{0:{1}}", s.value, width);
+  }
+};
+
+TEST(StdFormatTest, Parsing) {
+  std::string s = std::format("{0:{1}}", S{42}, 10);  // s == "        42"
+  EXPECT_EQ(s, "        42");
+}
+
+#if FMT_USE_INT128
+template <> struct std::formatter<__int128_t> : std::formatter<long long> {
+  auto format(__int128_t n, format_context& ctx) {
+    // Format as a long long since we only want to check if it is possible to
+    // specialize formatter for __int128_t.
+    return formatter<long long>::format(static_cast<long long>(n), ctx);
+  }
+};
+
+TEST(StdFormatTest, Int128) {
+  __int128_t n = 42;
+  auto s = std::format("{}", n);
+  EXPECT_EQ(s, "42");
+}
+#endif  // FMT_USE_INT128

test/test-assert.h

@@ -9,13 +9,19 @@
 #define FMT_TEST_ASSERT_H_
 
 #include <stdexcept>
+
 #include "gtest.h"
 
 class assertion_failure : public std::logic_error {
  public:
-  explicit assertion_failure(const char *message) : std::logic_error(message) {}
+  explicit assertion_failure(const char* message) : std::logic_error(message) {}
+
+ private:
+  virtual void avoid_weak_vtable();
 };
 
+void assertion_failure::avoid_weak_vtable() {}
+
 #define FMT_ASSERT(condition, message) \
   if (!(condition)) throw assertion_failure(message);
 

test/test-main.cc

@@ -6,26 +6,27 @@
 // For the license information refer to format.h.
 
 #include <cstdlib>
+
 #include "gtest.h"
 
 #ifdef _WIN32
-# include <windows.h>
+#  include <windows.h>
 #endif
 
 #ifdef _MSC_VER
-# include <crtdbg.h>
+#  include <crtdbg.h>
 #else
-# define _CrtSetReportFile(a, b)
-# define _CrtSetReportMode(a, b)
+#  define _CrtSetReportFile(a, b)
+#  define _CrtSetReportMode(a, b)
 #endif
 
-int main(int argc, char **argv) {
+int main(int argc, char** argv) {
 #ifdef _WIN32
   // Don't display any error dialogs. This also suppresses message boxes
   // on assertion failures in MinGW where _set_error_mode/CrtSetReportMode
   // doesn't help.
   SetErrorMode(SEM_FAILCRITICALERRORS | SEM_NOGPFAULTERRORBOX |
-    SEM_NOOPENFILEERRORBOX);
+               SEM_NOOPENFILEERRORBOX);
 #endif
   // Disable message boxes on assertion failures.
   _CrtSetReportMode(_CRT_ERROR, _CRTDBG_MODE_FILE | _CRTDBG_MODE_DEBUG);

test/time-test.cc

@@ -1,68 +0,0 @@
-// Formatting library for C++ - time formatting tests
-//
-// Copyright (c) 2012 - present, Victor Zverovich
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-#ifdef WIN32
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-
-#include "gmock.h"
-#include "fmt/locale.h"
-#include "fmt/time.h"
-
-TEST(TimeTest, Format) {
-  std::tm tm = std::tm();
-  tm.tm_year = 116;
-  tm.tm_mon  = 3;
-  tm.tm_mday = 25;
-  EXPECT_EQ("The date is 2016-04-25.",
-            fmt::format("The date is {:%Y-%m-%d}.", tm));
-}
-
-TEST(TimeTest, GrowBuffer) {
-  std::string s = "{:";
-  for (int i = 0; i < 30; ++i)
-    s += "%c";
-  s += "}\n";
-  std::time_t t = std::time(FMT_NULL);
-  fmt::format(s, *std::localtime(&t));
-}
-
-TEST(TimeTest, FormatToEmptyContainer) {
-  std::string s;
-  auto time = std::tm();
-  time.tm_sec = 42;
-  fmt::format_to(std::back_inserter(s), "{:%S}", time);
-  EXPECT_EQ(s, "42");
-}
-
-TEST(TimeTest, EmptyResult) {
-  EXPECT_EQ("", fmt::format("{}", std::tm()));
-}
-
-static bool EqualTime(const std::tm &lhs, const std::tm &rhs) {
-  return lhs.tm_sec == rhs.tm_sec &&
-         lhs.tm_min == rhs.tm_min &&
-         lhs.tm_hour == rhs.tm_hour &&
-         lhs.tm_mday == rhs.tm_mday &&
-         lhs.tm_mon == rhs.tm_mon &&
-         lhs.tm_year == rhs.tm_year &&
-         lhs.tm_wday == rhs.tm_wday &&
-         lhs.tm_yday == rhs.tm_yday &&
-         lhs.tm_isdst == rhs.tm_isdst;
-}
-
-TEST(TimeTest, LocalTime) {
-  std::time_t t = std::time(FMT_NULL);
-  std::tm tm = *std::localtime(&t);
-  EXPECT_TRUE(EqualTime(tm, fmt::localtime(t)));
-}
-
-TEST(TimeTest, GMTime) {
-  std::time_t t = std::time(FMT_NULL);
-  std::tm tm = *std::gmtime(&t);
-  EXPECT_TRUE(EqualTime(tm, fmt::gmtime(t)));
-}

test/util.cc

@@ -6,9 +6,10 @@
 // For the license information refer to format.h.
 
 #include "util.h"
+
 #include <cstring>
 
-void increment(char *s) {
+void increment(char* s) {
   for (int i = static_cast<int>(std::strlen(s)) - 1; i >= 0; --i) {
     if (s[i] != '9') {
       ++s[i];
@@ -30,15 +31,20 @@ std::string get_system_error(int error_code) {
 #endif
 }
 
-const char *const FILE_CONTENT = "Don't panic!";
+const char* const FILE_CONTENT = "Don't panic!";
 
-fmt::buffered_file open_buffered_file(FILE **fp) {
+fmt::buffered_file open_buffered_file(FILE** fp) {
+#if FMT_USE_FCNTL
   fmt::file read_end, write_end;
   fmt::file::pipe(read_end, write_end);
   write_end.write(FILE_CONTENT, std::strlen(FILE_CONTENT));
   write_end.close();
   fmt::buffered_file f = read_end.fdopen("r");
-  if (fp)
-    *fp = f.get();
+  if (fp) *fp = f.get();
+#else
+  fmt::buffered_file f("test-file", "w");
+  fputs(FILE_CONTENT, f.get());
+  if (fp) *fp = f.get();
+#endif
   return f;
 }

test/util.h

@@ -9,18 +9,18 @@
 #include <cstdio>
 #include <string>
 
-#include "fmt/posix.h"
+#include "fmt/os.h"
 
-enum {BUFFER_SIZE = 256};
+enum { BUFFER_SIZE = 256 };
 
 #ifdef _MSC_VER
-# define FMT_VSNPRINTF vsprintf_s
+#  define FMT_VSNPRINTF vsprintf_s
 #else
-# define FMT_VSNPRINTF vsnprintf
+#  define FMT_VSNPRINTF vsnprintf
 #endif
 
-template <std::size_t SIZE>
-void safe_sprintf(char (&buffer)[SIZE], const char *format, ...) {
+template <size_t SIZE>
+void safe_sprintf(char (&buffer)[SIZE], const char* format, ...) {
   std::va_list args;
   va_start(args, format);
   FMT_VSNPRINTF(buffer, SIZE, format, args);
@@ -28,19 +28,19 @@ void safe_sprintf(char (&buffer)[SIZE], const char *format, ...) {
 }
 
 // Increment a number in a string.
-void increment(char *s);
+void increment(char* s);
 
 std::string get_system_error(int error_code);
 
-extern const char *const FILE_CONTENT;
+extern const char* const FILE_CONTENT;
 
 // Opens a buffered file for reading.
-fmt::buffered_file open_buffered_file(FILE **fp = FMT_NULL);
+fmt::buffered_file open_buffered_file(FILE** fp = nullptr);
 
-inline FILE *safe_fopen(const char *filename, const char *mode) {
+inline FILE* safe_fopen(const char* filename, const char* mode) {
 #if defined(_WIN32) && !defined(__MINGW32__)
   // Fix MSVC warning about "unsafe" fopen.
-  FILE *f = 0;
+  FILE* f = 0;
   errno = fopen_s(&f, filename, mode);
   return f;
 #else
@@ -48,34 +48,33 @@ inline FILE *safe_fopen(const char *filename, const char *mode) {
 #endif
 }
 
-template <typename Char>
-class BasicTestString {
+template <typename Char> class BasicTestString {
  private:
   std::basic_string<Char> value_;
 
   static const Char EMPTY[];
 
  public:
-  explicit BasicTestString(const Char *value = EMPTY) : value_(value) {}
+  explicit BasicTestString(const Char* value = EMPTY) : value_(value) {}
 
-  const std::basic_string<Char> &value() const { return value_; }
+  const std::basic_string<Char>& value() const { return value_; }
 };
 
-template <typename Char>
-const Char BasicTestString<Char>::EMPTY[] = {0};
+template <typename Char> const Char BasicTestString<Char>::EMPTY[] = {0};
 
 typedef BasicTestString<char> TestString;
 typedef BasicTestString<wchar_t> TestWString;
 
 template <typename Char>
-std::basic_ostream<Char> &operator<<(
-    std::basic_ostream<Char> &os, const BasicTestString<Char> &s) {
+std::basic_ostream<Char>& operator<<(std::basic_ostream<Char>& os,
+                                     const BasicTestString<Char>& s) {
   os << s.value();
   return os;
 }
 
 class Date {
   int year_, month_, day_;
+
  public:
   Date(int year, int month, int day) : year_(year), month_(month), day_(day) {}