Remove unneeded stuff

Address enhancement request #1322.

The overload is provided in `ranges` (original `fmt::join` exists
currently in `format.h` for historical reasons.

Tests for prvalue and lvalue tuple arguments as well as the empty
tuple are provided in `ranges-test.cc`.

.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

.github/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.

.gitignore

@@ -31,3 +31,4 @@ CMakeFiles
 FMT.build
 Makefile
 run-msbuild.bat
+fmt.pc

.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:
@@ -73,53 +92,45 @@ 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
+    - name: Android NDK (Gradle)
+      language: android
       addons:
         apt:
           update: true
-          packages:
-            - g++-4.4
           sources:
             - ubuntu-toolchain-r-test
-      # Android
-    - language: android
+          packages:
+            - ninja-build
+            - curl
+            - tree
       android:
-      addons:
-        apt:
-          update: true
-      components:
-        - tools
-        - platform-tools
-        - android-21
-        - sys-img-armeabi-v7a-android-21
-      env:
-        - ANDROID=true
+        components:
+          - tools
+          - platform-tools
+          - android-25 # 7.0
+          - android-27 # 8.1
+          - android-28 # 9.0
+          - build-tools-28.0.3
       before_install:
-        - git submodule update --init --recursive
-        - sudo apt-get install wget unzip tree
+        # Install Gradle from https://sdkman.io/
+        - curl -s "https://get.sdkman.io" | bash > /dev/null
+        - source "$HOME/.sdkman/bin/sdkman-init.sh"
+        - sdk version
+        - sdk install gradle
+        - sdk use gradle
+        - gradle --version
       install:
         # Accept SDK Licenses + Install NDK
         - yes | sdkmanager --update > /dev/null 2>&1
         - sdkmanager ndk-bundle > /dev/null 2>&1
-        # Download Gradle 4.3.1 
-        - wget https://services.gradle.org/distributions/gradle-4.3.1-bin.zip
-        - mkdir -p gradle
-        - unzip -q -d ./gradle gradle-4.3.1-bin.zip
-        - export GRADLE=${TRAVIS_BUILD_DIR}/gradle/gradle-4.3.1/bin/gradle
       before_script:
-        - bash $GRADLE --version
-        - cd ./support
+        - pushd ./support
       script:
-        - bash $GRADLE clean assemble
+        - gradle clean
+        - gradle assemble
       after_success:
-        - cd ${TRAVIS_BUILD_DIR}
+        - popd;
         - tree ./libs
-  allow_failures:
-      # Errors
-    - env: COMPILER=g++-4.4 BUILD=Debug STANDARD=11
-      compiler: gcc
 
 before_script:
   - if [[ "${TRAVIS_OS_NAME}" == "linux" ]]; then export CXX=${COMPILER}; fi

CMakeLists.txt

@@ -1,12 +1,18 @@
-message(STATUS "CMake version: ${CMAKE_VERSION}")
-
 cmake_minimum_required(VERSION 3.1.0)
 
+# Use newer policies if available, up to most recent tested version of CMake.
+if(${CMAKE_VERSION} VERSION_LESS 3.11)
+  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)
 # or if it is the master project.
 set(MASTER_PROJECT OFF)
 if (CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
   set(MASTER_PROJECT ON)
+  message(STATUS "CMake version: ${CMAKE_VERSION}")
 endif ()
 
 # Joins arguments and places the results in ${result_var}.
@@ -21,21 +27,25 @@ 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)
+if (MASTER_PROJECT AND 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})
 endif ()
 
+option(FMT_USE_TEXT "Use the text library." OFF)
+
 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})
+option(FMT_FUZZ "Generate the fuzz target." OFF)
 
-project(FMT)
+project(FMT CXX)
 
 # Get version from core.h
 file(READ include/fmt/core.h core_h)
@@ -60,18 +70,21 @@ set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH}
 include(cxx14)
 include(CheckCXXCompilerFlag)
 
+set(FMT_REQUIRED_FEATURES cxx_auto_type cxx_variadic_templates)
+
 if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
   set(PEDANTIC_COMPILE_FLAGS -pedantic-errors -Wall -Wextra -pedantic
-      -Wold-style-cast -Wfloat-equal -Wlogical-op -Wundef
-      -Wredundant-decls -Wshadow -Wwrite-strings -Wpointer-arith
+      -Wold-style-cast -Wundef
+      -Wredundant-decls -Wwrite-strings -Wpointer-arith
       -Wcast-qual -Wformat=2 -Wmissing-include-dirs
       -Wcast-align -Wnon-virtual-dtor
       -Wctor-dtor-privacy -Wdisabled-optimization
-      -Winvalid-pch -Wmissing-declarations -Woverloaded-virtual
-      -Wno-ctor-dtor-privacy -Wno-dangling-else -Wno-float-equal
-      -Wno-format-nonliteral -Wno-sign-conversion -Wno-shadow)
+      -Winvalid-pch -Woverloaded-virtual
+      -Wconversion
+      -Wno-ctor-dtor-privacy -Wno-format-nonliteral -Wno-shadow)
   if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.6)
-      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wnoexcept)
+      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wnoexcept
+         -Wno-dangling-else -Wno-unused-local-typedefs)
   endif ()
   if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5.0)
       set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wdouble-promotion
@@ -82,33 +95,18 @@ if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
       set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wshift-overflow=2
           -Wnull-dereference -Wduplicated-cond)
   endif ()
-
   set(WERROR_FLAG -Werror)
 endif ()
 
-if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
-  set(PEDANTIC_COMPILE_FLAGS -Weverything -Wpedantic
-      -Wno-weak-vtables -Wno-padded -Wno-gnu-statement-expression
-      -Wno-c++98-compat -Wno-c++98-compat-pedantic -Wno-reserved-id-macro
-      -Wno-global-constructors -Wno-disabled-macro-expansion
-      -Wno-switch-enum -Wno-documentation-unknown-command
-      -Wno-gnu-string-literal-operator-template -Wno-unused-member-function
-      -Wno-format-nonliteral -Wno-missing-noreturn -Wno-undefined-func-template
-      -Wno-shadow -Wno-sign-conversion -Wno-used-but-marked-unused
-      -Wno-covered-switch-default -Wno-missing-variable-declarations
-      -Wno-double-promotion)
-
-  set(WERROR_FLAG -Werror)
-
-  check_cxx_compiler_flag(-Wno-zero-as-null-pointer-constant HAS_NULLPTR_WARNING)
+if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+  set(PEDANTIC_COMPILE_FLAGS -Wall -Wextra -pedantic -Wconversion
+      -Wno-sign-conversion)
+  check_cxx_compiler_flag(-Wzero-as-null-pointer-constant HAS_NULLPTR_WARNING)
   if (HAS_NULLPTR_WARNING)
-    set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wno-zero-as-null-pointer-constant)
-  endif ()
-
-  check_cxx_compiler_flag(-Wno-gnu-string-literal-operator-template HAS_GNU_UDL_WARNING)
-  if (HAS_GNU_UDL_WARNING)
-    set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wno-gnu-string-literal-operator-template)
+    set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS}
+        -Wzero-as-null-pointer-constant)
   endif ()
+  set(WERROR_FLAG -Werror)
 endif ()
 
 if (MSVC)
@@ -132,11 +130,18 @@ if (MASTER_PROJECT AND CMAKE_GENERATOR MATCHES "Visual Studio")
     ${CMAKE_MAKE_PROGRAM} -p:FrameworkPathOverride=\"${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)
@@ -148,17 +153,26 @@ function(add_headers VAR)
 endfunction()
 
 # Define the fmt library, its includes and the needed defines.
-add_headers(FMT_HEADERS core.h format.h format-inl.h ostream.h printf.h time.h
-                        ranges.h)
+add_headers(FMT_HEADERS chrono.h color.h compile.h core.h format.h format-inl.h
+                        locale.h ostream.h printf.h ranges.h
+                        safe-duration-cast.h)
 set(FMT_SOURCES src/format.cc)
 if (HAVE_OPEN)
   add_headers(FMT_HEADERS posix.h)
   set(FMT_SOURCES ${FMT_SOURCES} src/posix.cc)
 endif ()
 
+if (FMT_USE_TEXT)
+  set(FMT_SOURCES ${FMT_SOURCES} src/text/grapheme_break.cpp)
+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 (FMT_WERROR)
   target_compile_options(fmt PRIVATE ${WERROR_FLAG})
 endif ()
@@ -166,28 +180,40 @@ 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>)
 
+if (FMT_USE_TEXT)
+  target_include_directories(fmt PUBLIC
+    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/src/text>)
+endif ()
+
 set_target_properties(fmt PROPERTIES
   VERSION ${FMT_VERSION} SOVERSION ${CPACK_PACKAGE_VERSION_MAJOR}
   DEBUG_POSTFIX d)
 
 if (BUILD_SHARED_LIBS)
-  if (UNIX AND NOT APPLE)
+  if (UNIX AND NOT APPLE AND NOT ${CMAKE_SYSTEM_NAME} MATCHES "SunOS")
     # 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>)
@@ -197,9 +223,10 @@ 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}.")
+      "Installation directory for cmake files, relative to ${CMAKE_INSTALL_PREFIX}.")
   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)
@@ -213,11 +240,18 @@ if (FMT_INSTALL)
   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_LIBDIR}/pkgconfig CACHE PATH
+      "Installation directory for pkgconfig (.pc) files, relative to ${CMAKE_INSTALL_PREFIX}.")
+
   # Generate the version, config and target files into the build directory.
   write_basic_package_version_file(
     ${version_config}
     VERSION ${FMT_VERSION}
     COMPATIBILITY AnyNewerVersion)
+  configure_file(
+    "${PROJECT_SOURCE_DIR}/support/cmake/fmt.pc.in"
+    "${pkgconfig}"
+    @ONLY)
   configure_package_config_file(
     ${PROJECT_SOURCE_DIR}/support/cmake/fmt-config.cmake.in
     ${project_config}
@@ -237,7 +271,11 @@ if (FMT_INSTALL)
   # Install the library and headers.
   install(TARGETS ${INSTALL_TARGETS} EXPORT ${targets_export_name}
           DESTINATION ${FMT_LIB_DIR})
+
+  install(FILES $<TARGET_PDB_FILE:${INSTALL_TARGETS}>
+          DESTINATION ${FMT_LIB_DIR} OPTIONAL)
   install(FILES ${FMT_HEADERS} DESTINATION ${FMT_INC_DIR})
+  install(FILES "${pkgconfig}" DESTINATION "${FMT_PKGCONFIG_DIR}")
 endif ()
 
 if (FMT_DOC)
@@ -249,6 +287,11 @@ if (FMT_TEST)
   add_subdirectory(test)
 endif ()
 
+# Control fuzzing independent of the unit tests.
+if (FMT_FUZZ)
+  add_subdirectory(test/fuzzing)
+endif ()
+
 set(gitignore ${PROJECT_SOURCE_DIR}/.gitignore)
 if (MASTER_PROJECT AND EXISTS ${gitignore})
   # Get the list of ignored files from .gitignore.

CONTRIBUTING.md

@@ -0,0 +1,17 @@
+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
+
+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!

ChangeLog.rst

@@ -1,3 +1,770 @@
+6.0.0 - 2019-08-26
+------------------
+
+* Switched to the `MIT license
+  <https://github.com/fmtlib/fmt/blob/5a4b24613ba16cc689977c3b5bd8274a3ba1dd1f/LICENSE.rst>`_
+  with an optional exception that allows distributing binary code without
+  attribution.
+
+* Floating-point formatting is now locale-independent by default:
+
+  .. code:: c++
+
+     #include <locale>
+     #include <fmt/core.h>
+
+     int main() {
+       std::locale::global(std::locale("ru_RU.UTF-8"));
+       fmt::print("value = {}", 4.2);
+     }
+
+  prints "value = 4.2" regardless of the locale.
+
+  For locale-specific formatting use the ``n`` specifier:
+
+  .. code:: c++
+
+     std::locale::global(std::locale("ru_RU.UTF-8"));
+     fmt::print("value = {:n}", 4.2);
+
+  prints "value = 4,2".
+
+* Added an experimental Grisu floating-point formatting algorithm
+  implementation (disabled by default). To enable it compile with the
+  ``FMT_USE_GRISU`` macro defined to 1:
+
+  .. code:: c++
+
+     #define FMT_USE_GRISU 1
+     #include <fmt/format.h>
+
+     auto s = fmt::format("{}", 4.2); // formats 4.2 using Grisu
+
+  With Grisu enabled, {fmt} is 13x faster than ``std::ostringstream`` (libc++)
+  and 10x faster than ``sprintf`` on `dtoa-benchmark
+  <https://github.com/fmtlib/dtoa-benchmark>`_ (`full results
+  <https://fmt.dev/unknown_mac64_clang10.0.html>`_):
+
+  .. image:: https://user-images.githubusercontent.com/576385/
+             54883977-9fe8c000-4e28-11e9-8bde-272d122e7c52.jpg
+
+* Separated formatting and parsing contexts for consistency with
+  `C++20 std::format <http://eel.is/c++draft/format>`_, removing the
+  undocumented ``basic_format_context::parse_context()`` function.
+
+* Added `oss-fuzz <https://github.com/google/oss-fuzz>`_ support
+  (`#1199 <https://github.com/fmtlib/fmt/pull/1199>`_).
+  Thanks `@pauldreik (Paul Dreik) <https://github.com/pauldreik>`_.
+
+* ``formatter`` specializations now always take precedence over ``operator<<``
+  (`#952 <https://github.com/fmtlib/fmt/issues/952>`_):
+
+  .. code:: c++
+
+     #include <iostream>
+     #include <fmt/ostream.h>
+
+     struct S {};
+
+     std::ostream& operator<<(std::ostream& os, S) {
+       return os << 1;
+     }
+
+     template <>
+     struct fmt::formatter<S> : fmt::formatter<int> {
+       auto format(S, format_context& ctx) {
+         return formatter<int>::format(2, ctx);
+       }
+     };
+
+     int main() {
+       std::cout << S() << "\n"; // prints 1 using operator<<
+       fmt::print("{}\n", S());  // prints 2 using formatter
+     }
+
+* Introduced the experimental ``fmt::compile`` function that does format string
+  compilation (`#618 <https://github.com/fmtlib/fmt/issues/618>`_,
+  `#1169 <https://github.com/fmtlib/fmt/issues/1169>`_,
+  `#1171 <https://github.com/fmtlib/fmt/pull/1171>`_):
+
+  .. code:: c++
+
+     #include <fmt/compile.h>
+
+     auto f = fmt::compile<int>("{}");
+     std::string s = fmt::format(f, 42); // can be called multiple times to format
+                                         // different values
+     // s == "42"
+
+  It moves the cost of parsing a format string outside of the format function
+  which can be beneficial when identically formatting many objects of the same
+  types. Thanks `@stryku (Mateusz Janek) <https://github.com/stryku>`_.
+
+* Added the ``%`` format specifier that formats floating-point values as
+  percentages (`#1060 <https://github.com/fmtlib/fmt/pull/1060>`_,
+  `#1069 <https://github.com/fmtlib/fmt/pull/1069>`_,
+  `#1071 <https://github.com/fmtlib/fmt/pull/1071>`_):
+
+  .. code:: c++
+
+     auto s = fmt::format("{:.1%}", 0.42); // s == "42.0%"
+
+  Thanks `@gawain-bolton (Gawain Bolton) <https://github.com/gawain-bolton>`_.
+
+* Implemented precision for floating-point durations
+  (`#1004 <https://github.com/fmtlib/fmt/issues/1004>`_,
+  `#1012 <https://github.com/fmtlib/fmt/pull/1012>`_):
+
+  .. code:: c++
+
+     auto s = fmt::format("{:.1}", std::chrono::duration<double>(1.234));
+     // s == 1.2s
+
+  Thanks `@DanielaE (Daniela Engert) <https://github.com/DanielaE>`_.
+
+* Implemented ``chrono`` format specifiers ``%Q`` and ``%q`` that give the value
+  and the unit respectively (`#1019 <https://github.com/fmtlib/fmt/pull/1019>`_):
+
+  .. code:: c++
+
+     auto value = fmt::format("{:%Q}", 42s); // value == "42"
+     auto unit  = fmt::format("{:%q}", 42s); // unit == "s"
+
+  Thanks `@DanielaE (Daniela Engert) <https://github.com/DanielaE>`_.
+
+* Fixed handling of dynamic width in chrono formatter:
+
+  .. code:: c++
+
+     auto s = fmt::format("{0:{1}%H:%M:%S}", std::chrono::seconds(12345), 12);
+     //                        ^ width argument index                     ^ width
+     // s == "03:25:45    "
+
+  Thanks Howard Hinnant.
+
+* Removed deprecated ``fmt/time.h``. Use ``fmt/chrono.h`` instead.
+
+* Added ``fmt::format`` and ``fmt::vformat`` overloads that take ``text_style``
+  (`#993 <https://github.com/fmtlib/fmt/issues/993>`_,
+  `#994 <https://github.com/fmtlib/fmt/pull/994>`_):
+
+  .. code:: c++
+
+     #include <fmt/color.h>
+
+     std::string message = fmt::format(fmt::emphasis::bold | fg(fmt::color::red),
+                                       "The answer is {}.", 42);
+
+  Thanks `@Naios (Denis Blank) <https://github.com/Naios>`_.
+
+* Removed the deprecated color API (``print_colored``). Use the new API, namely
+  ``print`` overloads that take ``text_style`` instead.
+
+* Made ``std::unique_ptr`` and ``std::shared_ptr`` formattable as pointers via
+  ``fmt::ptr`` (`#1121 <https://github.com/fmtlib/fmt/pull/1121>`_):
+
+  .. code:: c++
+
+     std::unique_ptr<int> p = ...;
+     fmt::print("{}", fmt::ptr(p)); // prints p as a pointer
+
+  Thanks `@sighingnow (Tao He) <https://github.com/sighingnow>`_.
+
+* Made ``print`` and ``vprint`` report I/O errors
+  (`#1098 <https://github.com/fmtlib/fmt/issues/1098>`_,
+  `#1099 <https://github.com/fmtlib/fmt/pull/1099>`_).
+  Thanks `@BillyDonahue (Billy Donahue) <https://github.com/BillyDonahue>`_.
+
+* Marked deprecated APIs with the ``[[deprecated]]`` attribute and removed
+  internal uses of deprecated APIs
+  (`#1022 <https://github.com/fmtlib/fmt/pull/1022>`_).
+  Thanks `@eliaskosunen (Elias Kosunen) <https://github.com/eliaskosunen>`_.
+
+* Modernized the codebase using more C++11 features and removing workarounds.
+  Most importantly, ``buffer_context`` is now an alias template, so
+  use ``buffer_context<T>`` instead of ``buffer_context<T>::type``.
+  These features require GCC 4.8 or later.
+
+* ``formatter`` specializations now always take precedence over implicit
+  conversions to ``int`` and the undocumented ``convert_to_int`` trait
+  is now deprecated.
+
+* Moved the undocumented ``basic_writer``, ``writer``, and ``wwriter`` types
+  to the ``internal`` namespace.
+
+* Removed deprecated ``basic_format_context::begin()``. Use ``out()`` instead.
+
+* Disallowed passing the result of ``join`` as an lvalue to prevent misuse.
+
+* Refactored the undocumented structs that represent parsed format specifiers
+  to simplify the API and allow multibyte fill.
+
+* Moved SFINAE to template parameters to reduce symbol sizes.
+
+* Switched to ``fputws`` for writing wide strings so that it's no longer
+  required to call ``_setmode`` on Windows
+  (`#1229 <https://github.com/fmtlib/fmt/issues/1229>`_,
+  `#1243 <https://github.com/fmtlib/fmt/pull/1243>`_).
+  Thanks `@jackoalan (Jack Andersen) <https://github.com/jackoalan>`_.
+
+* Improved literal-based API
+  (`#1254 <https://github.com/fmtlib/fmt/pull/1254>`_).
+  Thanks `@sylveon (Charles Milette) <https://github.com/sylveon>`_.
+
+* Added support for exotic platforms without ``uintptr_t`` such as IBM i
+  (AS/400) which has 128-bit pointers and only 64-bit integers
+  (`#1059 <https://github.com/fmtlib/fmt/issues/1059>`_).
+
+* Added `Sublime Text syntax highlighting config
+  <https://github.com/fmtlib/fmt/blob/master/support/C%2B%2B.sublime-syntax>`_
+  (`#1037 <https://github.com/fmtlib/fmt/issues/1037>`_).
+  Thanks `@Kronuz (Germán Méndez Bravo) <https://github.com/Kronuz>`_.
+
+* Added the ``FMT_ENFORCE_COMPILE_STRING`` macro to enforce the use of
+  compile-time format strings
+  (`#1231 <https://github.com/fmtlib/fmt/pull/1231>`_).
+  Thanks `@jackoalan (Jack Andersen) <https://github.com/jackoalan>`_.
+
+* Stopped setting ``CMAKE_BUILD_TYPE`` if {fmt} is a subproject
+  (`#1081 <https://github.com/fmtlib/fmt/issues/1081>`_).
+
+* Various build improvements
+  (`#1039 <https://github.com/fmtlib/fmt/pull/1039>`_,
+  `#1078 <https://github.com/fmtlib/fmt/pull/1078>`_,
+  `#1091 <https://github.com/fmtlib/fmt/pull/1091>`_,
+  `#1103 <https://github.com/fmtlib/fmt/pull/1103>`_,
+  `#1177 <https://github.com/fmtlib/fmt/pull/1177>`_).
+  Thanks `@luncliff (Park DongHa) <https://github.com/luncliff>`_,
+  `@jasonszang (Jason Shuo Zang) <https://github.com/jasonszang>`_,
+  `@olafhering (Olaf Hering) <https://github.com/olafhering>`_,
+  `@Lecetem <https://github.com/Lectem>`_,
+  `@pauldreik (Paul Dreik) <https://github.com/pauldreik>`_.
+
+* Improved documentation
+  (`#1049 <https://github.com/fmtlib/fmt/issues/1049>`_,
+  `#1051 <https://github.com/fmtlib/fmt/pull/1051>`_,
+  `#1083 <https://github.com/fmtlib/fmt/pull/1083>`_,
+  `#1113 <https://github.com/fmtlib/fmt/pull/1113>`_,
+  `#1114 <https://github.com/fmtlib/fmt/pull/1114>`_,
+  `#1146 <https://github.com/fmtlib/fmt/issues/1146>`_,
+  `#1180 <https://github.com/fmtlib/fmt/issues/1180>`_,
+  `#1250 <https://github.com/fmtlib/fmt/pull/1250>`_,
+  `#1252 <https://github.com/fmtlib/fmt/pull/1252>`_,
+  `#1265 <https://github.com/fmtlib/fmt/pull/1265>`_).
+  Thanks `@mikelui (Michael Lui) <https://github.com/mikelui>`_,
+  `@foonathan (Jonathan Müller) <https://github.com/foonathan>`_,
+  `@BillyDonahue (Billy Donahue) <https://github.com/BillyDonahue>`_,
+  `@jwakely (Jonathan Wakely) <https://github.com/jwakely>`_,
+  `@kaisbe (Kais Ben Salah) <https://github.com/kaisbe>`_,
+  `@sdebionne (Samuel Debionne) <https://github.com/sdebionne>`_.
+
+* Fixed ambiguous formatter specialization in ``fmt/ranges.h``
+  (`#1123 <https://github.com/fmtlib/fmt/issues/1123>`_).
+
+* Fixed formatting of a non-empty ``std::filesystem::path`` which is an
+  infinitely deep range of its components
+  (`#1268 <https://github.com/fmtlib/fmt/issues/1268>`_).
+
+* Fixed handling of general output iterators when formatting characters
+  (`#1056 <https://github.com/fmtlib/fmt/issues/1056>`_,
+  `#1058 <https://github.com/fmtlib/fmt/pull/1058>`_).
+  Thanks `@abolz (Alexander Bolz) <https://github.com/abolz>`_.
+
+* Fixed handling of output iterators in ``formatter`` specialization for
+  ranges (`#1064 <https://github.com/fmtlib/fmt/issues/1064>`_).
+
+* Fixed handling of exotic character types
+  (`#1188 <https://github.com/fmtlib/fmt/issues/1188>`_).
+
+* Made chrono formatting work with exceptions disabled
+  (`#1062 <https://github.com/fmtlib/fmt/issues/1062>`_).
+
+* Fixed DLL visibility issues
+  (`#1134 <https://github.com/fmtlib/fmt/pull/1134>`_,
+  `#1147 <https://github.com/fmtlib/fmt/pull/1147>`_).
+  Thanks `@denchat <https://github.com/denchat>`_.
+
+* Disabled the use of UDL template extension on GCC 9
+  (`#1148 <https://github.com/fmtlib/fmt/issues/1148>`_).
+
+* Removed misplaced ``format`` compile-time checks from ``printf``
+  (`#1173 <https://github.com/fmtlib/fmt/issues/1173>`_).
+
+* Fixed issues in the experimental floating-point formatter
+  (`#1072 <https://github.com/fmtlib/fmt/issues/1072>`_,
+  `#1129 <https://github.com/fmtlib/fmt/issues/1129>`_,
+  `#1153 <https://github.com/fmtlib/fmt/issues/1153>`_,
+  `#1155 <https://github.com/fmtlib/fmt/pull/1155>`_,
+  `#1210 <https://github.com/fmtlib/fmt/issues/1210>`_,
+  `#1222 <https://github.com/fmtlib/fmt/issues/1222>`_).
+  Thanks `@alabuzhev (Alex Alabuzhev) <https://github.com/alabuzhev>`_.
+
+* Fixed bugs discovered by fuzzing or during fuzzing integration
+  (`#1124 <https://github.com/fmtlib/fmt/issues/1124>`_,
+  `#1127 <https://github.com/fmtlib/fmt/issues/1127>`_,
+  `#1132 <https://github.com/fmtlib/fmt/issues/1132>`_,
+  `#1135 <https://github.com/fmtlib/fmt/pull/1135>`_,
+  `#1136 <https://github.com/fmtlib/fmt/issues/1136>`_,
+  `#1141 <https://github.com/fmtlib/fmt/issues/1141>`_,
+  `#1142 <https://github.com/fmtlib/fmt/issues/1142>`_,
+  `#1178 <https://github.com/fmtlib/fmt/issues/1178>`_,
+  `#1179 <https://github.com/fmtlib/fmt/issues/1179>`_,
+  `#1194 <https://github.com/fmtlib/fmt/issues/1194>`_).
+  Thanks `@pauldreik (Paul Dreik) <https://github.com/pauldreik>`_.
+
+* Fixed building tests on FreeBSD and Hurd
+  (`#1043 <https://github.com/fmtlib/fmt/issues/1043>`_).
+  Thanks `@jackyf (Eugene V. Lyubimkin) <https://github.com/jackyf>`_.
+
+* Fixed various warnings and compilation issues
+  (`#998 <https://github.com/fmtlib/fmt/pull/998>`_,
+  `#1006 <https://github.com/fmtlib/fmt/pull/1006>`_,
+  `#1008 <https://github.com/fmtlib/fmt/issues/1008>`_,
+  `#1011 <https://github.com/fmtlib/fmt/issues/1011>`_,
+  `#1025 <https://github.com/fmtlib/fmt/issues/1025>`_,
+  `#1027 <https://github.com/fmtlib/fmt/pull/1027>`_,
+  `#1028 <https://github.com/fmtlib/fmt/pull/1028>`_,
+  `#1029 <https://github.com/fmtlib/fmt/pull/1029>`_,
+  `#1030 <https://github.com/fmtlib/fmt/pull/1030>`_,
+  `#1031 <https://github.com/fmtlib/fmt/pull/1031>`_,
+  `#1054 <https://github.com/fmtlib/fmt/pull/1054>`_,
+  `#1063 <https://github.com/fmtlib/fmt/issues/1063>`_,
+  `#1068 <https://github.com/fmtlib/fmt/pull/1068>`_,
+  `#1074 <https://github.com/fmtlib/fmt/pull/1074>`_,
+  `#1075 <https://github.com/fmtlib/fmt/pull/1075>`_,
+  `#1079 <https://github.com/fmtlib/fmt/pull/1079>`_,
+  `#1086 <https://github.com/fmtlib/fmt/pull/1086>`_,
+  `#1088 <https://github.com/fmtlib/fmt/issues/1088>`_,
+  `#1089 <https://github.com/fmtlib/fmt/pull/1089>`_,
+  `#1094 <https://github.com/fmtlib/fmt/pull/1094>`_,
+  `#1101 <https://github.com/fmtlib/fmt/issues/1101>`_,
+  `#1102 <https://github.com/fmtlib/fmt/pull/1102>`_,
+  `#1105 <https://github.com/fmtlib/fmt/issues/1105>`_,
+  `#1107 <https://github.com/fmtlib/fmt/pull/1107>`_,
+  `#1115 <https://github.com/fmtlib/fmt/issues/1115>`_,
+  `#1117 <https://github.com/fmtlib/fmt/issues/1117>`_,
+  `#1118 <https://github.com/fmtlib/fmt/issues/1118>`_,
+  `#1120 <https://github.com/fmtlib/fmt/issues/1120>`_,
+  `#1123 <https://github.com/fmtlib/fmt/issues/1123>`_,
+  `#1139 <https://github.com/fmtlib/fmt/pull/1139>`_,
+  `#1140 <https://github.com/fmtlib/fmt/issues/1140>`_,
+  `#1143 <https://github.com/fmtlib/fmt/issues/1143>`_,
+  `#1144 <https://github.com/fmtlib/fmt/pull/1144>`_,
+  `#1150 <https://github.com/fmtlib/fmt/pull/1150>`_,
+  `#1151 <https://github.com/fmtlib/fmt/pull/1151>`_,
+  `#1152 <https://github.com/fmtlib/fmt/issues/1152>`_,
+  `#1154 <https://github.com/fmtlib/fmt/issues/1154>`_,
+  `#1156 <https://github.com/fmtlib/fmt/issues/1156>`_,
+  `#1159 <https://github.com/fmtlib/fmt/pull/1159>`_,
+  `#1175 <https://github.com/fmtlib/fmt/issues/1175>`_,
+  `#1181 <https://github.com/fmtlib/fmt/issues/1181>`_,
+  `#1186 <https://github.com/fmtlib/fmt/issues/1186>`_,
+  `#1187 <https://github.com/fmtlib/fmt/pull/1187>`_,
+  `#1191 <https://github.com/fmtlib/fmt/pull/1191>`_,
+  `#1197 <https://github.com/fmtlib/fmt/issues/1197>`_,
+  `#1200 <https://github.com/fmtlib/fmt/issues/1200>`_,
+  `#1203 <https://github.com/fmtlib/fmt/issues/1203>`_,
+  `#1205 <https://github.com/fmtlib/fmt/issues/1205>`_,
+  `#1206 <https://github.com/fmtlib/fmt/pull/1206>`_,
+  `#1213 <https://github.com/fmtlib/fmt/issues/1213>`_,
+  `#1214 <https://github.com/fmtlib/fmt/issues/1214>`_,
+  `#1217 <https://github.com/fmtlib/fmt/pull/1217>`_,
+  `#1228 <https://github.com/fmtlib/fmt/issues/1228>`_,
+  `#1230 <https://github.com/fmtlib/fmt/pull/1230>`_,
+  `#1232 <https://github.com/fmtlib/fmt/issues/1232>`_,
+  `#1235 <https://github.com/fmtlib/fmt/pull/1235>`_,
+  `#1236 <https://github.com/fmtlib/fmt/pull/1236>`_,
+  `#1240 <https://github.com/fmtlib/fmt/issues/1240>`_).
+  Thanks `@DanielaE (Daniela Engert) <https://github.com/DanielaE>`_,
+  `@mwinterb <https://github.com/mwinterb>`_,
+  `@eliaskosunen (Elias Kosunen) <https://github.com/eliaskosunen>`_,
+  `@morinmorin <https://github.com/morinmorin>`_,
+  `@ricco19 (Brian Ricciardelli) <https://github.com/ricco19>`_,
+  `@waywardmonkeys (Bruce Mitchener) <https://github.com/waywardmonkeys>`_,
+  `@chronoxor (Ivan Shynkarenka) <https://github.com/chronoxor>`_,
+  `@remyabel <https://github.com/remyabel>`_,
+  `@pauldreik (Paul Dreik) <https://github.com/pauldreik>`_,
+  `@gsjaardema (Greg Sjaardema) <https://github.com/gsjaardema>`_,
+  `@rcane (Ronny Krüger) <https://github.com/rcane>`_,
+  `@mocabe <https://github.com/mocabe>`_,
+  `@denchat <https://github.com/denchat>`_,
+  `@cjdb (Christopher Di Bella) <https://github.com/cjdb>`_,
+  `@HazardyKnusperkeks (Björn Schäpers) <https://github.com/HazardyKnusperkeks>`_,
+  `@vedranmiletic (Vedran Miletić) <https://github.com/vedranmiletic>`_,
+  `@jackoalan (Jack Andersen) <https://github.com/jackoalan>`_,
+  `@DaanDeMeyer (Daan De Meyer) <https://github.com/DaanDeMeyer>`_,
+  `@starkmapper (Mark Stapper) <https://github.com/starkmapper>`_.
+
+5.3.0 - 2018-12-28
+------------------
+
+* Introduced experimental chrono formatting support:
+
+  .. code:: c++
+
+     #include <fmt/chrono.h>
+
+     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);
+     }
+
+  prints::
+
+     Default format: 42s 100ms
+     strftime-like format: 03:15:30
+
+* Added experimental support for emphasis (bold, italic, underline,
+  strikethrough), colored output to a file stream, and improved colored
+  formatting API
+  (`#961 <https://github.com/fmtlib/fmt/pull/961>`_,
+  `#967 <https://github.com/fmtlib/fmt/pull/967>`_,
+  `#973 <https://github.com/fmtlib/fmt/pull/973>`_):
+
+  .. code:: c++
+
+     #include <fmt/color.h>
+
+     int main() {
+       print(fg(fmt::color::crimson) | fmt::emphasis::bold,
+             "Hello, {}!\n", "world");
+       print(fg(fmt::color::floral_white) | bg(fmt::color::slate_gray) |
+             fmt::emphasis::underline, "Hello, {}!\n", "мир");
+       print(fg(fmt::color::steel_blue) | fmt::emphasis::italic,
+             "Hello, {}!\n", "世界");
+     }
+
+  prints the following on modern terminals with RGB color support:
+
+  .. image:: https://user-images.githubusercontent.com/576385/
+             50405788-b66e7500-076e-11e9-9592-7324d1f951d8.png
+
+  Thanks `@Rakete1111 (Nicolas) <https://github.com/Rakete1111>`_.
+
+* Added support for 4-bit terminal colors
+  (`#968 <https://github.com/fmtlib/fmt/issues/968>`_,
+  `#974 <https://github.com/fmtlib/fmt/pull/974>`_)
+
+  .. code:: c++
+
+     #include <fmt/color.h>
+
+     int main() {
+       print(fg(fmt::terminal_color::red), "stop\n");
+     }
+
+  Note that these colors vary by terminal:
+
+  .. image:: https://user-images.githubusercontent.com/576385/
+             50405925-dbfc7e00-0770-11e9-9b85-333fab0af9ac.png
+
+  Thanks `@Rakete1111 (Nicolas) <https://github.com/Rakete1111>`_.
+
+* Parameterized formatting functions on the type of the format string
+  (`#880 <https://github.com/fmtlib/fmt/issues/880>`_,
+  `#881 <https://github.com/fmtlib/fmt/pull/881>`_,
+  `#883 <https://github.com/fmtlib/fmt/pull/883>`_,
+  `#885 <https://github.com/fmtlib/fmt/pull/885>`_,
+  `#897 <https://github.com/fmtlib/fmt/pull/897>`_,
+  `#920 <https://github.com/fmtlib/fmt/issues/920>`_).
+  Any object of type ``S`` that has an overloaded ``to_string_view(const S&)``
+  returning ``fmt::string_view`` can be used as a format string:
+
+  .. code:: c++
+
+     namespace my_ns {
+     inline string_view to_string_view(const my_string& s) {
+       return {s.data(), s.length()};
+     }
+     }
+
+     std::string message = fmt::format(my_string("The answer is {}."), 42);
+
+  Thanks `@DanielaE (Daniela Engert) <https://github.com/DanielaE>`_.
+
+* Made ``std::string_view`` work as a format string
+  (`#898 <https://github.com/fmtlib/fmt/pull/898>`_):
+
+  .. code:: c++
+
+     auto message = fmt::format(std::string_view("The answer is {}."), 42);
+
+  Thanks `@DanielaE (Daniela Engert) <https://github.com/DanielaE>`_.
+
+* Added wide string support to compile-time format string checks
+  (`#924 <https://github.com/fmtlib/fmt/pull/924>`_):
+
+  .. code:: c++
+
+     print(fmt(L"{:f}"), 42); // compile-time error: invalid type specifier
+
+  Thanks `@XZiar <https://github.com/XZiar>`_.
+
+* Made colored print functions work with wide strings
+  (`#867 <https://github.com/fmtlib/fmt/pull/867>`_):
+
+  .. code:: c++
+
+     #include <fmt/color.h>
+
+     int main() {
+       print(fg(fmt::color::red), L"{}\n", 42);
+     }
+
+  Thanks `@DanielaE (Daniela Engert) <https://github.com/DanielaE>`_.
+
+* Introduced experimental Unicode support
+  (`#628 <https://github.com/fmtlib/fmt/issues/628>`_,
+  `#891 <https://github.com/fmtlib/fmt/pull/891>`_):
+
+  .. code:: c++
+
+     using namespace fmt::literals;
+     auto s = fmt::format("{:*^5}"_u, "🤡"_u); // s == "**🤡**"_u
+
+* Improved locale support:
+
+  .. code:: c++
+
+     #include <fmt/locale.h>
+
+     struct numpunct : std::numpunct<char> {
+      protected:
+       char do_thousands_sep() const override { return '~'; }
+     };
+
+     std::locale loc;
+     auto s = fmt::format(std::locale(loc, new numpunct()), "{:n}", 1234567);
+     // s == "1~234~567"
+
+* Constrained formatting functions on proper iterator types
+  (`#921 <https://github.com/fmtlib/fmt/pull/921>`_).
+  Thanks `@DanielaE (Daniela Engert) <https://github.com/DanielaE>`_.
+
+* Added ``make_printf_args`` and ``make_wprintf_args`` functions
+  (`#934 <https://github.com/fmtlib/fmt/pull/934>`_).
+  Thanks `@tnovotny <https://github.com/tnovotny>`_.
+
+* Deprecated ``fmt::visit``, ``parse_context``, and ``wparse_context``.
+  Use ``fmt::visit_format_arg``, ``format_parse_context``, and
+  ``wformat_parse_context`` instead.
+
+* Removed undocumented ``basic_fixed_buffer`` which has been superseded by the
+  iterator-based API
+  (`#873 <https://github.com/fmtlib/fmt/issues/873>`_,
+  `#902 <https://github.com/fmtlib/fmt/pull/902>`_).
+  Thanks `@superfunc (hollywood programmer) <https://github.com/superfunc>`_.
+
+* Disallowed repeated leading zeros in an argument ID:
+
+  .. code:: c++
+
+     fmt::print("{000}", 42); // error
+
+* Reintroduced support for gcc 4.4.
+
+* Fixed compilation on platforms with exotic ``double``
+  (`#878 <https://github.com/fmtlib/fmt/issues/878>`_).
+
+* Improved documentation
+  (`#164 <https://github.com/fmtlib/fmt/issues/164>`_,
+  `#877 <https://github.com/fmtlib/fmt/issues/877>`_,
+  `#901 <https://github.com/fmtlib/fmt/pull/901>`_,
+  `#906 <https://github.com/fmtlib/fmt/pull/906>`_,
+  `#979 <https://github.com/fmtlib/fmt/pull/979>`_).
+  Thanks `@kookjr (Mathew Cucuzella) <https://github.com/kookjr>`_,
+  `@DarkDimius (Dmitry Petrashko) <https://github.com/DarkDimius>`_,
+  `@HecticSerenity <https://github.com/HecticSerenity>`_.
+
+* Added pkgconfig support which makes it easier to consume the library from
+  meson and other build systems
+  (`#916 <https://github.com/fmtlib/fmt/pull/916>`_).
+  Thanks `@colemickens (Cole Mickens) <https://github.com/colemickens>`_.
+
+* Various build improvements
+  (`#909 <https://github.com/fmtlib/fmt/pull/909>`_,
+  `#926 <https://github.com/fmtlib/fmt/pull/926>`_,
+  `#937 <https://github.com/fmtlib/fmt/pull/937>`_,
+  `#953 <https://github.com/fmtlib/fmt/pull/953>`_,
+  `#959 <https://github.com/fmtlib/fmt/pull/959>`_).
+  Thanks `@tchaikov (Kefu Chai) <https://github.com/tchaikov>`_,
+  `@luncliff (Park DongHa) <https://github.com/luncliff>`_,
+  `@AndreasSchoenle (Andreas Schönle) <https://github.com/AndreasSchoenle>`_,
+  `@hotwatermorning <https://github.com/hotwatermorning>`_,
+  `@Zefz (JohanJansen) <https://github.com/Zefz>`_.
+
+* Improved ``string_view`` construction performance
+  (`#914 <https://github.com/fmtlib/fmt/pull/914>`_).
+  Thanks `@gabime (Gabi Melman) <https://github.com/gabime>`_.
+
+* Fixed non-matching char types
+  (`#895 <https://github.com/fmtlib/fmt/pull/895>`_).
+  Thanks `@DanielaE (Daniela Engert) <https://github.com/DanielaE>`_.
+
+* Fixed ``format_to_n`` with ``std::back_insert_iterator``
+  (`#913 <https://github.com/fmtlib/fmt/pull/913>`_).
+  Thanks `@DanielaE (Daniela Engert) <https://github.com/DanielaE>`_.
+
+* Fixed locale-dependent formatting
+  (`#905 <https://github.com/fmtlib/fmt/issues/905>`_).
+
+* Fixed various compiler warnings and errors
+  (`#882 <https://github.com/fmtlib/fmt/pull/882>`_,
+  `#886 <https://github.com/fmtlib/fmt/pull/886>`_,
+  `#933 <https://github.com/fmtlib/fmt/pull/933>`_,
+  `#941 <https://github.com/fmtlib/fmt/pull/941>`_,
+  `#931 <https://github.com/fmtlib/fmt/issues/931>`_,
+  `#943 <https://github.com/fmtlib/fmt/pull/943>`_,
+  `#954 <https://github.com/fmtlib/fmt/pull/954>`_,
+  `#956 <https://github.com/fmtlib/fmt/pull/956>`_,
+  `#962 <https://github.com/fmtlib/fmt/pull/962>`_,
+  `#965 <https://github.com/fmtlib/fmt/issues/965>`_,
+  `#977 <https://github.com/fmtlib/fmt/issues/977>`_,
+  `#983 <https://github.com/fmtlib/fmt/pull/983>`_,
+  `#989 <https://github.com/fmtlib/fmt/pull/989>`_).
+  Thanks `@Luthaf (Guillaume Fraux) <https://github.com/Luthaf>`_,
+  `@stevenhoving (Steven Hoving) <https://github.com/stevenhoving>`_,
+  `@christinaa (Kristina Brooks) <https://github.com/christinaa>`_,
+  `@lgritz (Larry Gritz) <https://github.com/lgritz>`_,
+  `@DanielaE (Daniela Engert) <https://github.com/DanielaE>`_,
+  `@0x8000-0000 (Sign Bit) <https://github.com/0x8000-0000>`_,
+  `@liuping1997 <https://github.com/liuping1997>`_.
+
+5.2.1 - 2018-09-21
+------------------
+
+* Fixed ``visit`` lookup issues on gcc 7 & 8
+  (`#870 <https://github.com/fmtlib/fmt/pull/870>`_).
+  Thanks `@medithe <https://github.com/medithe>`_.
+
+* Fixed linkage errors on older gcc.
+
+* Prevented ``fmt/range.h`` from specializing ``fmt::basic_string_view``
+  (`#865 <https://github.com/fmtlib/fmt/issues/865>`_,
+  `#868 <https://github.com/fmtlib/fmt/pull/868>`_).
+  Thanks `@hhggit (dual) <https://github.com/hhggit>`_.
+
+* Improved error message when formatting unknown types
+  (`#872 <https://github.com/fmtlib/fmt/pull/872>`_).
+  Thanks `@foonathan (Jonathan Müller) <https://github.com/foonathan>`_,
+
+* Disabled templated user-defined literals when compiled under nvcc
+  (`#875 <https://github.com/fmtlib/fmt/pull/875>`_).
+  Thanks `@CandyGumdrop (Candy Gumdrop) <https://github.com/CandyGumdrop>`_,
+
+* Fixed ``format_to`` formatting to ``wmemory_buffer``
+  (`#874 <https://github.com/fmtlib/fmt/issues/874>`_).
+
+5.2.0 - 2018-09-13
+------------------
+
+* Optimized format string parsing and argument processing which resulted in up
+  to 5x speed up on long format strings and significant performance boost on
+  various benchmarks. For example, version 5.2 is 2.22x faster than 5.1 on
+  decimal integer formatting with ``format_to`` (macOS, clang-902.0.39.2):
+
+  ==================  =======  =======
+  Method              Time, s  Speedup
+  ==================  =======  =======
+  fmt::format 5.1      0.58
+  fmt::format 5.2      0.35     1.66x
+  fmt::format_to 5.1   0.51
+  fmt::format_to 5.2   0.23     2.22x
+  sprintf              0.71
+  std::to_string       1.01
+  std::stringstream    1.73
+  ==================  =======  =======
+
+* Changed the ``fmt`` macro from opt-out to opt-in to prevent name collisions.
+  To enable it define the ``FMT_STRING_ALIAS`` macro to 1 before including
+  ``fmt/format.h``:
+
+  .. code:: c++
+
+     #define FMT_STRING_ALIAS 1
+     #include <fmt/format.h>
+     std::string answer = format(fmt("{}"), 42);
+
+* Added compile-time format string checks to ``format_to`` overload that takes
+  ``fmt::memory_buffer`` (`#783 <https://github.com/fmtlib/fmt/issues/783>`_):
+
+  .. code:: c++
+
+     fmt::memory_buffer buf;
+     // Compile-time error: invalid type specifier.
+     fmt::format_to(buf, fmt("{:d}"), "foo");
+
+* Moved experimental color support to ``fmt/color.h`` and enabled the
+  new API by default. The old API can be enabled by defining the
+  ``FMT_DEPRECATED_COLORS`` macro.
+
+* Added formatting support for types explicitly convertible to
+  ``fmt::string_view``:
+
+  .. code:: c++
+
+     struct foo {
+       explicit operator fmt::string_view() const { return "foo"; }
+     };
+     auto s = format("{}", foo());
+
+  In particular, this makes formatting function work with
+  ``folly::StringPiece``.
+
+* Implemented preliminary support for ``char*_t`` by replacing the ``format``
+  function overloads with a single function template parameterized on the string
+  type.
+
+* Added support for dynamic argument lists
+  (`#814 <https://github.com/fmtlib/fmt/issues/814>`_,
+  `#819 <https://github.com/fmtlib/fmt/pull/819>`_).
+  Thanks `@MikePopoloski (Michael Popoloski)
+  <https://github.com/MikePopoloski>`_.
+
+* Reduced executable size overhead for embedded targets using newlib nano by
+  making locale dependency optional
+  (`#839 <https://github.com/fmtlib/fmt/pull/839>`_).
+  Thanks `@teajay-fr (Thomas Benard) <https://github.com/teajay-fr>`_.
+
+* Keep ``noexcept`` specifier when exceptions are disabled
+  (`#801 <https://github.com/fmtlib/fmt/issues/801>`_,
+  `#810 <https://github.com/fmtlib/fmt/pull/810>`_).
+  Thanks `@qis (Alexej Harm) <https://github.com/qis>`_.
+
+* Fixed formatting of user-defined types providing ``operator<<`` with
+  ``format_to_n``
+  (`#806 <https://github.com/fmtlib/fmt/pull/806>`_).
+  Thanks `@mkurdej (Marek Kurdej) <https://github.com/mkurdej>`_.
+
+* Fixed dynamic linkage of new symbols
+  (`#808 <https://github.com/fmtlib/fmt/issues/808>`_).
+
+* Fixed global initialization issue
+  (`#807 <https://github.com/fmtlib/fmt/issues/807>`_):
+
+  .. code:: c++
+
+     // This works on compilers with constexpr support.
+     static const std::string answer = fmt::format("{}", 42);
+
+* Fixed various compiler warnings and errors
+  (`#804 <https://github.com/fmtlib/fmt/pull/804>`_,
+  `#809 <https://github.com/fmtlib/fmt/issues/809>`_,
+  `#811 <https://github.com/fmtlib/fmt/pull/811>`_,
+  `#822 <https://github.com/fmtlib/fmt/issues/822>`_,
+  `#827 <https://github.com/fmtlib/fmt/pull/827>`_,
+  `#830 <https://github.com/fmtlib/fmt/issues/830>`_,
+  `#838 <https://github.com/fmtlib/fmt/pull/838>`_,
+  `#843 <https://github.com/fmtlib/fmt/issues/843>`_,
+  `#844 <https://github.com/fmtlib/fmt/pull/844>`_,
+  `#851 <https://github.com/fmtlib/fmt/issues/851>`_,
+  `#852 <https://github.com/fmtlib/fmt/pull/852>`_,
+  `#854 <https://github.com/fmtlib/fmt/pull/854>`_).
+  Thanks `@henryiii (Henry Schreiner) <https://github.com/henryiii>`_,
+  `@medithe <https://github.com/medithe>`_, and
+  `@eliasdaler (Elias Daler) <https://github.com/eliasdaler>`_.
+
 5.1.0 - 2018-07-05
 ------------------
 
@@ -16,7 +783,7 @@
   ``color`` enum) is now deprecated.
   (`#762 <https://github.com/fmtlib/fmt/issues/762>`_
   `#767 <https://github.com/fmtlib/fmt/pull/767>`_).
-  Thanks `@Remotion (Remo) <https://github.com/Remotion>`_.
+  thanks `@Remotion (Remo) <https://github.com/Remotion>`_.
 
 * Added quotes to strings in ranges and tuples
   (`#766 <https://github.com/fmtlib/fmt/pull/766>`_).
@@ -97,7 +864,7 @@
 
 * Implemented ``constexpr`` parsing of format strings and `compile-time format
   string checks
-  <http://fmtlib.net/dev/api.html#compile-time-format-string-checks>`_. For
+  <https://fmt.dev/dev/api.html#compile-time-format-string-checks>`_. For
   example
 
   .. code:: c++
@@ -158,7 +925,7 @@
             throw format_error("invalid specifier");
 
 * Added `iterator support
-  <http://fmtlib.net/dev/api.html#output-iterator-support>`_:
+  <https://fmt.dev/dev/api.html#output-iterator-support>`_:
 
   .. code:: c++
 
@@ -169,7 +936,7 @@
      fmt::format_to(std::back_inserter(out), "{}", 42);
 
 * Added the `format_to_n
-  <http://fmtlib.net/dev/api.html#_CPPv2N3fmt11format_to_nE8OutputItNSt6size_tE11string_viewDpRK4Args>`_
+  <https://fmt.dev/dev/api.html#_CPPv2N3fmt11format_to_nE8OutputItNSt6size_tE11string_viewDpRK4Args>`_
   function that restricts the output to the specified number of characters
   (`#298 <https://github.com/fmtlib/fmt/issues/298>`_):
 
@@ -180,7 +947,7 @@
      // out == "1234" (without terminating '\0')
 
 * Added the `formatted_size
-  <http://fmtlib.net/dev/api.html#_CPPv2N3fmt14formatted_sizeE11string_viewDpRK4Args>`_
+  <https://fmt.dev/dev/api.html#_CPPv2N3fmt14formatted_sizeE11string_viewDpRK4Args>`_
   function for computing the output size:
 
   .. code:: c++
@@ -190,7 +957,7 @@
      auto size = fmt::formatted_size("{}", 12345); // size == 5
 
 * Improved compile times by reducing dependencies on standard headers and
-  providing a lightweight `core API <http://fmtlib.net/dev/api.html#core-api>`_:
+  providing a lightweight `core API <https://fmt.dev/dev/api.html#core-api>`_:
 
   .. code:: c++
 
@@ -202,7 +969,7 @@
   <https://github.com/fmtlib/fmt#compile-time-and-code-bloat>`_.
 
 * Added the `make_format_args
-  <http://fmtlib.net/dev/api.html#_CPPv2N3fmt16make_format_argsEDpRK4Args>`_
+  <https://fmt.dev/dev/api.html#_CPPv2N3fmt16make_format_argsEDpRK4Args>`_
   function for capturing formatting arguments:
 
   .. code:: c++
@@ -284,7 +1051,7 @@
      fmt::format("{} {two}", 1, fmt::arg("two", 2));
 
 * Removed the write API in favor of the `format API
-  <http://fmtlib.net/dev/api.html#format-api>`_ with compile-time handling of
+  <https://fmt.dev/dev/api.html#format-api>`_ with compile-time handling of
   format strings.
 
 * Disallowed formatting of multibyte strings into a wide character target
@@ -687,7 +1454,7 @@
 
 3.0.1 - 2016-11-01
 ------------------
-* Fixed handling of thousands seperator
+* Fixed handling of thousands separator
   (`#353 <https://github.com/fmtlib/fmt/issues/353>`_).
 
 * Fixed handling of ``unsigned char`` strings
@@ -745,10 +1512,10 @@
   Including ``format.h`` from the ``cppformat`` directory is deprecated
   but works via a proxy header which will be removed in the next major version.
   
-  The documentation is now available at http://fmtlib.net.
+  The documentation is now available at https://fmt.dev.
 
 * Added support for `strftime <http://en.cppreference.com/w/cpp/chrono/c/strftime>`_-like
-  `date and time formatting <http://fmtlib.net/3.0.0/api.html#date-and-time-formatting>`_
+  `date and time formatting <https://fmt.dev/3.0.0/api.html#date-and-time-formatting>`_
   (`#283 <https://github.com/fmtlib/fmt/issues/283>`_):
 
   .. code:: c++
@@ -780,7 +1547,7 @@
     // s == "The date is 2012-12-9"
 
 * Added support for `custom argument formatters
-  <http://fmtlib.net/3.0.0/api.html#argument-formatters>`_
+  <https://fmt.dev/3.0.0/api.html#argument-formatters>`_
   (`#235 <https://github.com/fmtlib/fmt/issues/235>`_).
 
 * Added support for locale-specific integer formatting with the ``n`` specifier
@@ -1160,7 +1927,7 @@ Documentation
 
 
 * Added `Building the documentation
-  <http://fmtlib.net/2.0.0/usage.html#building-the-documentation>`_
+  <https://fmt.dev/2.0.0/usage.html#building-the-documentation>`_
   section to the documentation.
 
 * Documentation build script is now compatible with Python 3 and newer pip versions.

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

@@ -6,80 +6,82 @@
 
 .. 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
+
+.. image:: https://img.shields.io/badge/stackoverflow-fmt-blue.svg
+   :alt: Ask questions at StackOverflow with the tag fmt
+   :target: http://stackoverflow.com/questions/tagged/fmt
+
+.. image:: https://oss-fuzz-build-logs.storage.googleapis.com/badges/libfmt.svg
+   :alt: fmt is continuously fuzzed att oss-fuzz
+   :target: https://bugs.chromium.org/p/oss-fuzz/issues/list?colspec=ID%20Type%20Component%20Status%20Proj%20Reported%20Owner%20Summary&q=proj%3Dfmt&can=1
 
 **{fmt}** is an open-source formatting library for C++.
-It can be used as a safe and fast alternative to (s)printf and IOStreams.
+It can be used as a safe and fast alternative to (s)printf and iostreams.
 
-`Documentation <http://fmtlib.net/latest/>`__
+`Documentation <https://fmt.dev/latest/>`__
 
-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>`__.
+Q&A: ask questions on `StackOverflow with the tag fmt <http://stackoverflow.com/questions/tagged/fmt>`_.
 
 Features
 --------
 
-* Replacement-based `format API <http://fmtlib.net/dev/api.html>`_ with
+* Replacement-based `format API <https://fmt.dev/dev/api.html>`_ with
   positional arguments for localization.
-* `Format string syntax <http://fmtlib.net/dev/syntax.html>`_ similar to the one
+* `Format string syntax <https://fmt.dev/dev/syntax.html>`_ similar to the one
   of `str.format <https://docs.python.org/2/library/stdtypes.html#str.format>`_
   in Python.
 * Safe `printf implementation
-  <http://fmtlib.net/latest/api.html#printf-formatting-functions>`_ including
+  <https://fmt.dev/latest/api.html#printf-formatting>`_ including
   the POSIX extension for positional arguments.
+* Implementation of `C++20 std::format <https://fmt.dev/Text%20Formatting.html>`__.
 * 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++
+* High performance: faster than common standard library implementations of
+  `printf <http://en.cppreference.com/w/cpp/io/c/fprintf>`_ and
+  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://github.com/fmtlib/fmt/tree/master/test>`_ and is continuously fuzzed.
 * Safety: the library is fully type safe, errors in format strings can be
   reported at compile time, automatic memory management prevents buffer overflow
   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
+* `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
   (``-Wall -Wextra -pedantic``).
 * Support for wide strings.
 * 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/latest/>`_ for more details.
 
 Examples
 --------
 
-This prints ``Hello, world!`` to stdout:
+Print ``Hello, world!`` to ``stdout``:
 
 .. code:: c++
 
-    fmt::print("Hello, {}!", "world");  // uses Python-like format string syntax
-    fmt::printf("Hello, %s!", "world"); // uses printf format string syntax
+    fmt::print("Hello, {}!", "world");  // Python-like format string syntax
+    fmt::printf("Hello, %s!", "world"); // printf format string syntax
 
-Arguments can be accessed by position and arguments' indices can be repeated:
+Format a string and use positional arguments:
 
 .. code:: c++
 
-    std::string s = fmt::format("{0}{1}{0}", "abra", "cad");
-    // s == "abracadabra"
+    std::string s = fmt::format("I'd rather be {1} than {0}.", "right", "happy");
+    // s == "I'd rather be happy than right."
 
-Format strings can be checked at compile time:
+Check a format string at compile time:
 
 .. code:: c++
 
     // test.cc
+    #define FMT_STRING_ALIAS 1
     #include <fmt/format.h>
     std::string s = format(fmt("{2}"), 42);
 
@@ -87,7 +89,7 @@ Format strings can be checked at compile time:
 
     $ c++ -Iinclude -std=c++14 test.cc
     ...
-    test.cc:3:17: note: in instantiation of function template specialization 'fmt::v5::format<S, int>' requested here
+    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
@@ -97,7 +99,7 @@ Format strings can be checked at compile time:
           context_.on_error("argument index out of range");
                    ^
 
-{fmt} can be used as a safe portable replacement for ``itoa``
+Use {fmt} as a safe portable replacement for ``itoa``
 (`godbolt <https://godbolt.org/g/NXmpU4>`_):
 
 .. code:: c++
@@ -105,31 +107,36 @@ Format strings can be checked at compile time:
     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()
+    // access the string with to_string(buf) or buf.data()
 
-An object of any user-defined type for which there is an overloaded
-:code:`std::ostream` insertion operator (``operator<<``) can be formatted:
+Format objects of user-defined types via a simple `extension API
+<https://fmt.dev/latest/api.html#formatting-user-defined-types>`_:
 
 .. code:: c++
 
-    #include "fmt/ostream.h"
+    #include "fmt/format.h"
 
-    class Date {
-      int year_, month_, day_;
-     public:
-      Date(int year, int month, int day) : year_(year), month_(month), day_(day) {}
+    struct date {
+      int year, month, day;
+    };
 
-      friend std::ostream &operator<<(std::ostream &os, const Date &d) {
-        return os << d.year_ << '-' << d.month_ << '-' << d.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));
+    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>`_
+Create your own functions similar to `format
+<https://fmt.dev/latest/api.html#format>`_ and
+`print <https://fmt.dev/latest/api.html#print>`_
 which take arbitrary arguments (`godbolt <https://godbolt.org/g/MHjHVf>`_):
 
 .. code:: c++
@@ -147,19 +154,138 @@ which take arbitrary arguments (`godbolt <https://godbolt.org/g/MHjHVf>`_):
     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.
+improve compile times and reduce code size compared to a fully parameterized
+version.
+
+Benchmarks
+----------
+
+Speed tests
+~~~~~~~~~~~
+
+================= ============= ===========
+Library           Method        Run Time, s
+================= ============= ===========
+libc              printf          1.01
+libc++            std::ostream    3.04
+{fmt} 1632f72     fmt::print      0.86
+tinyformat 2.0.1  tfm::printf     3.23
+Boost Format 1.67 boost::format   7.98
+Folly Format      folly::format   2.23
+================= ============= ===========
+
+{fmt} is the fastest of the benchmarked methods, ~17% faster than ``printf``.
+
+The above results were generated by building ``tinyformat_test.cpp`` on macOS
+10.14.3 with ``clang++ -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 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 10x faster than ``std::ostringstream`` and ``sprintf`` on floating-point
+formatting (`dtoa-benchmark <https://github.com/fmtlib/dtoa-benchmark>`_)
+and as fast as `double-conversion <https://github.com/google/double-conversion>`_:
+
+.. image:: https://user-images.githubusercontent.com/576385/54883977-9fe8c000-4e28-11e9-8bde-272d122e7c52.jpg
+   :target: https://fmt.dev/unknown_mac64_clang10.0.html
+
+Compile time and code bloat
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The script `bloat-test.py
+<https://github.com/fmtlib/format-benchmark/blob/master/bloat-test.py>`_
+from `format-benchmark <https://github.com/fmtlib/format-benchmark>`_
+tests compile time and code bloat for nontrivial projects.
+It generates 100 translation units and uses ``printf()`` or its alternative
+five times in each to simulate a medium sized project.  The resulting
+executable size and compile time (Apple LLVM version 8.1.0 (clang-802.0.42),
+macOS Sierra, best of three) is shown in the following tables.
+
+**Optimized build (-O3)**
+
+============= =============== ==================== ==================
+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
+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
+and Folly Format have the largest overheads.
+
+``printf+string`` is the same as ``printf`` but with extra ``<string>``
+include to measure the overhead of the latter.
+
+**Non-optimized build**
+
+============= =============== ==================== ==================
+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
+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.
+
+Running the tests
+~~~~~~~~~~~~~~~~~
+
+Please refer to `Building the library`__ for the instructions on how to build
+the library and run the unit tests.
+
+__ https://fmt.dev/latest/usage.html#building-the-library
+
+Benchmarks reside in a separate repository,
+`format-benchmarks <https://github.com/fmtlib/format-benchmark>`_,
+so to run the benchmarks you first need to clone this repository and
+generate Makefiles with CMake::
+
+    $ git clone --recursive https://github.com/fmtlib/format-benchmark.git
+    $ cd format-benchmark
+    $ cmake .
+
+Then you can run the speed test::
+
+    $ make speed-test
+
+or the bloat test::
+
+    $ make bloat-test
 
 Projects using this library
 ---------------------------
 
-* `0 A.D. <http://play0ad.com/>`_: A free, open-source, cross-platform real-time strategy game
+* `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
+* `AvioBook <https://www.aviobook.aero/en>`_: A comprehensive aircraft
+  operations suite
+  
+* `Celestia <https://celestia.space/>`_: Real-time 3D visualization of space
 
-* `CUAUV <http://cuauv.org/>`_: Cornell University's autonomous underwater vehicle
+* `Ceph <https://ceph.com/>`_: A scalable distributed storage system
+
+* `ccache <https://ccache.dev/>`_: A compiler cache
+
+* `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
@@ -180,6 +306,8 @@ Projects using this library
 
 * `FiveM <https://fivem.net/>`_: a modification framework for GTA V
 
+* `MongoDB <https://mongodb.com/>`_: Distributed document database
+
 * `MongoDB Smasher <https://github.com/duckie/mongo_smasher>`_: A small tool to
   generate randomized datasets
 
@@ -194,7 +322,11 @@ Projects using this library
 
 * `readpe <https://bitbucket.org/sys_dev/readpe>`_: Read Portable Executable
 
-* `redis-cerberus <https://github.com/HunanTV/redis-cerberus>`_: A Redis cluster proxy
+* `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
@@ -202,11 +334,11 @@ Projects using this library
 * `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
+* `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
+* `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
 
@@ -214,9 +346,10 @@ Projects using this library
 
 * `Touch Surgery <https://www.touchsurgery.com/>`_: Surgery simulator
 
-* `TrinityCore <https://github.com/TrinityCore/TrinityCore>`_: Open-source MMORPG framework
+* `TrinityCore <https://github.com/TrinityCore/TrinityCore>`_: Open-source
+  MMORPG framework
 
-`More... <https://github.com/search?q=cppformat&type=Code>`_
+`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
@@ -228,28 +361,28 @@ 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
+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
+printf
 ~~~~~~
 
-The good thing about printf is that it is pretty fast and readily available
+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, ...))
+doesn't support user-defined types. ``printf`` also has safety issues although
+they are somewhat mitigated 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
+to ``printf`` but it is not a part of C99 and may not be available on some
 platforms.
 
-IOStreams
+iostreams
 ~~~~~~~~~
 
-The main issue with IOStreams is best illustrated with an example:
+The main issue with iostreams is best illustrated with an example:
 
 .. code:: c++
 
@@ -261,21 +394,20 @@ which is a lot of typing compared to printf:
 
     printf("%.2f\n", 1.23456);
 
-Matthew Wilson, the author of FastFormat, referred to this situation with
-IOStreams as "chevron hell". IOStreams doesn't support positional arguments
-by design.
+Matthew Wilson, the author of FastFormat, called this "chevron hell". iostreams
+don't support positional arguments by design.
 
-The good part is that IOStreams supports user-defined types and is safe
-although error reporting is awkward.
+The good part is that iostreams support user-defined types and are safe although
+error handling is awkward.
 
-Boost Format library
-~~~~~~~~~~~~~~~~~~~~
+Boost Format
+~~~~~~~~~~~~
 
-This is a very powerful library which supports both printf-like format
-strings and positional arguments. The main its 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`_).
+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
 ~~~~~~~~~~
@@ -296,147 +428,58 @@ too restrictive for using it in some projects.
 Loki SafeFormat
 ~~~~~~~~~~~~~~~
 
-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.
+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 and
+makes unconventional use of ``operator()`` for passing format arguments.
 
 Tinyformat
 ~~~~~~~~~~
 
-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.
+This library supports ``printf``-like format strings and is very small .
+It doesn't support positional arguments and wrapping it in C++98 is somewhat
+difficult. Tinyformat relies on iostreams which limits its performance.
 
 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::Writer`` on Karma's own benchmark,
+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_int`` 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>`_.
 
-Benchmarks
-----------
+FAQ
+---
 
-Speed tests
-~~~~~~~~~~~
+Q: how can I capture formatting arguments and format them later?
 
-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>`_.
+A: use ``std::tuple``:
 
-================= ============= ===========
-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
-================= ============= ===========
+.. code:: c++
 
-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.
+   template <typename... Args>
+   auto capture(const Args&... args) {
+     return std::make_tuple(args...);
+   }
 
-Compile time and code bloat
-~~~~~~~~~~~~~~~~~~~~~~~~~~~
+   auto print_message = [](const auto&... args) {
+     fmt::print(args...);
+   };
 
-The script `bloat-test.py
-<https://github.com/fmtlib/format-benchmark/blob/master/bloat-test.py>`_
-from `format-benchmark <https://github.com/fmtlib/format-benchmark>`_
-tests compile time and code bloat for nontrivial projects.
-It generates 100 translation units and uses ``printf()`` or its alternative
-five times in each to simulate a medium sized project.  The resulting
-executable size and compile time (Apple LLVM version 8.1.0 (clang-802.0.42),
-macOS Sierra, best of three) is shown in the following tables.
-
-**Optimized build (-O3)**
-
-============= =============== ==================== ==================
-Method        Compile Time, s Executable size, KiB Stripped size, KiB
-============= =============== ==================== ==================
-printf                    2.7                   29                 26
-printf+string            18.4                   29                 26
-IOStreams                34.6                   59                 55
-fmt                      22.0                   37                 34
-tinyformat               51.8                  103                 97
-Boost Format            120.5                  762                739
-Folly Format            158.7                  102                 87
-============= =============== ==================== ==================
-
-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
-has by far the largest overheads.
-
-``printf+string`` is the same as ``printf`` but with extra ``<string>``
-include to measure the overhead of the latter.
-
-**Non-optimized build**
-
-============= =============== ==================== ==================
-Method        Compile Time, s Executable size, KiB Stripped size, KiB
-============= =============== ==================== ==================
-printf                    2.4                   33                 30
-printf+string            18.5                   33                 30
-IOStreams                31.9                   56                 52
-fmt                      20.9                   56                 51
-tinyformat               38.9                   88                 82
-Boost Format             64.8                  366                304
-Folly Format            113.5                  442                428
-============= =============== ==================== ==================
-
-``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.
-
-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
-
-Benchmarks reside in a separate repository,
-`format-benchmarks <https://github.com/fmtlib/format-benchmark>`_,
-so to run the benchmarks you first need to clone this repository and
-generate Makefiles with CMake::
-
-    $ git clone --recursive https://github.com/fmtlib/format-benchmark.git
-    $ cd format-benchmark
-    $ cmake .
-
-Then you can run the speed test::
-
-    $ make speed-test
-
-or the bloat test::
-
-    $ make bloat-test
+   // Capture and store arguments:
+   auto args = capture("{} {}", 42, "foo");
+   // Do formatting:
+   std::apply(print_message, args);
 
 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>`_
+<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
@@ -448,7 +491,7 @@ It only applies if you distribute the documentation of fmt.
 Acknowledgments
 ---------------
 
-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

doc/CMakeLists.txt

@@ -6,7 +6,7 @@ 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)
+  SOURCES api.rst syntax.rst usage.rst build.py conf.py _templates/layout.html)
 
 install(DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/html/
         DESTINATION share/doc/fmt OPTIONAL)

doc/_templates/layout.html

@@ -58,7 +58,7 @@
                 <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>

doc/api.rst

@@ -10,7 +10,9 @@ The {fmt} library API consists of the following parts:
   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
+* :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/ostream.h <ostream-api>`: ``std::ostream`` support
 * :ref:`fmt/printf.h <printf-api>`: ``printf`` formatting
 
@@ -23,41 +25,43 @@ 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>`
-imilar to that of Python's `str.format
+similar to that of Python's `str.format
 <http://docs.python.org/3/library/stdtypes.html#str.format>`_.
 They take *format_str* and *args* as arguments.
 
 *format_str* is a format string that contains literal text and replacement
 fields surrounded by braces ``{}``. The fields are replaced with formatted
-arguments in the resulting string.
+arguments in the resulting string. A function taking *format_str* doesn't
+participate in an overload resolution if the latter is not a string.
 
 *args* is an argument list representing objects to be formatted.
 
 .. _format:
 
-.. doxygenfunction:: format(string_view, const Args&...)
-.. doxygenfunction:: vformat(string_view, format_args)
+.. doxygenfunction:: format(const S&, Args&&...)
+.. doxygenfunction:: vformat(const S&, basic_format_args<buffer_context<Char>>)
 
 .. _print:
 
-.. doxygenfunction:: print(string_view, const Args&...)
+.. doxygenfunction:: print(const S&, Args&&...)
 .. doxygenfunction:: vprint(string_view, format_args)
 
-.. doxygenfunction:: print(std::FILE *, string_view, const Args&...)
+.. doxygenfunction:: print(std::FILE *, const S&, Args&&...)
 .. doxygenfunction:: vprint(std::FILE *, string_view, format_args)
-
-.. doxygenfunction:: print(std::FILE *, wstring_view, const 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
 --------------
 
 .. doxygenfunction:: fmt::make_format_args(const Args&...)
@@ -90,12 +94,13 @@ Format API
 ``fmt/format.h`` defines the full format API providing compile-time format
 string checks, output iterator and user-defined type support.
 
-Compile-time format string checks
+Compile-time Format String Checks
 ---------------------------------
 
+.. doxygendefine:: FMT_STRING
 .. doxygendefine:: fmt
 
-Formatting user-defined types
+Formatting User-defined Types
 -----------------------------
 
 To make a user-defined type formattable, specialize the ``formatter<T>`` struct
@@ -113,7 +118,7 @@ template and implement ``parse`` and ``format`` methods::
 
     template <typename FormatContext>
     auto format(const point &p, FormatContext &ctx) {
-      return format_to(ctx.begin(), "({:.1f}, {:.1f})", p.x, p.y);
+      return format_to(ctx.out(), "({:.1f}, {:.1f})", p.x, p.y);
     }
   };
   }
@@ -127,18 +132,62 @@ Then you can pass objects of type ``point`` to any formatting function::
 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
+:file:`fmt/chrono.h` for an advanced example of how to parse the format string and
 customize the formatted output.
 
-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.
+You can also reuse existing formatters, for example::
 
-Output iterator support
+  enum class color {red, green, blue};
+
+  template <>
+  struct fmt::formatter<color>: formatter<string_view> {
+    // parse is inherited from formatter<string_view>.
+    template <typename FormatContext>
+    auto format(color c, FormatContext &ctx) {
+      string_view name = "unknown";
+      switch (c) {
+      case color::red:   name = "red"; break;
+      case color::green: name = "green"; break;
+      case color::blue:  name = "blue"; break;
+      }
+      return formatter<string_view>::format(name, ctx);
+    }
+  };
+
+You can also write a formatter for a hierarchy of classes::
+
+  #include <type_traits>
+  #include <fmt/format.h>
+
+  struct A {
+    virtual ~A() {}
+    virtual std::string name() const { return "A"; }
+  };
+
+  struct B : A {
+    virtual std::string name() const { return "B"; }
+  };
+
+  template <typename T>
+  struct fmt::formatter<T, std::enable_if_t<std::is_base_of<A, T>::value, char>> :
+      fmt::formatter<std::string> {
+    template <typename FormatCtx>
+    auto format(const A& a, FormatCtx& ctx) {
+      return fmt::formatter<std::string>::format(a.name(), ctx);
+    }
+  };
+
+  int main() {
+    B b;
+    A& a = b;
+    fmt::print("{}", a); // prints "B"
+  }
+
+Output Iterator Support
 -----------------------
 
-.. doxygenfunction:: fmt::format_to(OutputIt, string_view, const Args&...)
-.. doxygenfunction:: fmt::format_to_n(OutputIt, size_t, string_view, const Args&...)
+.. doxygenfunction:: fmt::format_to(OutputIt, const S&, Args&&...)
+.. doxygenfunction:: fmt::format_to_n(OutputIt, std::size_t, string_view, Args&&...)
 .. doxygenstruct:: fmt::format_to_n_result
    :members:
 
@@ -154,17 +203,27 @@ The following user-defined literals are defined in ``fmt/format.h``.
 Utilities
 ---------
 
+.. doxygenstruct:: fmt::is_char
+
+.. doxygentypedef:: fmt::char_t
+
 .. doxygenfunction:: fmt::formatted_size(string_view, const Args&...)
 
 .. doxygenfunction:: fmt::to_string(const T&)
 
 .. doxygenfunction:: fmt::to_wstring(const T&)
 
+.. doxygenfunction:: fmt::to_string_view(const Char *)
+
+.. doxygenfunction:: fmt::join(const Range&, string_view)
+
+.. doxygenfunction:: fmt::join(It, It, string_view)
+
 .. 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
@@ -181,7 +240,7 @@ the value of ``errno`` being preserved by library functions.
 
 .. _formatstrings:
 
-Custom allocators
+Custom Allocators
 -----------------
 
 The {fmt} library supports custom dynamic memory allocators.
@@ -216,29 +275,29 @@ 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.
 
-Custom formatting of built-in types
+Custom Formatting of Built-in Types
 -----------------------------------
 
 It is possible to change the way arguments are formatted by providing a
 custom argument formatter class::
 
-  using arg_formatter =
-    fmt::arg_formatter<fmt::back_insert_range<fmt::internal::buffer>>;
+  using arg_formatter = fmt::arg_formatter<fmt::buffer_range<char>>;
 
   // 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)
-      : arg_formatter(ctx, spec) {}
+    custom_arg_formatter(fmt::format_context& ctx,
+                         fmt::format_parse_context* parse_ctx = nullptr,
+                         fmt::format_specs* spec = nullptr)
+      : arg_formatter(ctx, parse_ctx, spec) {}
 
     using arg_formatter::operator();
 
-    void operator()(int value) {
-      if (spec().type() == 'x')
-        (*this)(static_cast<unsigned>(value)); // convert to unsigned and format
-      else
-        arg_formatter::operator()(value);
+    auto operator()(int value) {
+      if (specs() && specs()->type == 'x')
+        return (*this)(static_cast<unsigned>(value)); // convert to unsigned and format
+      return arg_formatter::operator()(value);
     }
   };
 
@@ -260,16 +319,41 @@ custom argument formatter class::
 .. doxygenclass:: fmt::arg_formatter
    :members:
 
-.. _time-api:
+.. _ranges-api:
 
-Date and time formatting
+Ranges and Tuple Formatting
+===========================
+
+The library also supports convenient formatting of ranges and tuples::
+
+  #include <fmt/ranges.h>
+
+  std::tuple<char, int, float> t{'a', 1, 2.0f};
+  // Prints "('a', 1, 2.0)"
+  fmt::print("{}", t);
+
+
+NOTE: currently, the overload of ``fmt::join`` for iterables exists in the main
+``format.h`` header, but expect this to change in the future.
+
+Using ``fmt::join``, you can separate tuple elements with a custom separator::
+
+  #include <fmt/ranges.h>
+
+  std::tuple<int, char> t = {1, 'a'};
+  // Prints "1, a"
+  fmt::print("{}", fmt::join(t, ", "));
+
+.. _chrono-api:
+
+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)
@@ -280,7 +364,7 @@ The format string syntax is described in the documentation of
 
 .. _ostream-api:
 
-``std::ostream`` support
+``std::ostream`` Support
 ========================
 
 ``fmt/ostream.h`` provides ``std::ostream`` support including formatting of
@@ -301,11 +385,11 @@ 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::ostream&, string_view, 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.
@@ -315,10 +399,10 @@ the POSIX extension for positional arguments. Unlike their standard
 counterparts, the ``fmt`` functions are type-safe and throw an exception if an
 argument type doesn't match its format specification.
 
-.. doxygenfunction:: printf(string_view, const Args&...)
+.. doxygenfunction:: printf(const S&, const Args&...)
 
-.. doxygenfunction:: fprintf(std::FILE *, string_view, const Args&...)
+.. doxygenfunction:: fprintf(std::FILE *, const S&, const Args&...)
 
-.. doxygenfunction:: fprintf(std::ostream&, string_view, const Args&...)
+.. doxygenfunction:: fprintf(std::basic_ostream<Char>&, const S&, const Args&...)
 
-.. doxygenfunction:: sprintf(string_view, const Args&...)
+.. doxygenfunction:: sprintf(const S&, const Args&...)

doc/build.py

@@ -6,7 +6,7 @@ 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']
+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']
 
 def pip_install(package, commit=None, **kwargs):
   "Install package using pip."
@@ -89,9 +89,12 @@ def build_docs(version='dev', **kwargs):
                           FMT_USE_VARIADIC_TEMPLATES=1 \
                           FMT_USE_RVALUE_REFERENCES=1 \
                           FMT_USE_USER_DEFINED_LITERALS=1 \
+                          FMT_USE_ALIAS_TEMPLATES=1 \
                           FMT_API= \
                           "FMT_BEGIN_NAMESPACE=namespace fmt {{" \
-                          "FMT_END_NAMESPACE=}}"
+                          "FMT_END_NAMESPACE=}}" \
+                          "FMT_STRING_ALIAS=1" \
+                          "FMT_ENABLE_IF(B)="
       EXCLUDE_SYMBOLS   = fmt::internal::* StringValue write_str
     '''.format(include_dir, doxyxml_dir).encode('UTF-8'))
   if p.returncode != 0:

doc/index.rst

@@ -1,7 +1,7 @@
 Overview
 ========
 
-**fmt** (formerly cppformat) is an open-source formatting library.
+**fmt** is an open-source formatting library.
 It can be used as a fast and safe alternative to printf and IOStreams.
 
 .. raw:: html
@@ -40,7 +40,7 @@ The ``fmt::format`` function returns a string "The answer is 42.". You can use
   format_to(out, "For a moment, {} happened.", "nothing");
   out.data(); // returns a pointer to the formatted data
 
-The ``fmt::print`` function performs formatting and writes the result to a file:
+The ``fmt::print`` function performs formatting and writes the result to a stream:
 
 .. code:: c++
 
@@ -94,7 +94,7 @@ Safety
 
 The library is fully type safe, automatic memory management prevents buffer
 overflow, errors in format strings are reported using exceptions or at compile
-tim. For example, the code
+time. For example, the code
 
 .. code:: c++
 
@@ -109,7 +109,8 @@ string", because the argument ``"forty-two"`` is a string while the format code
   format(fmt("The answer is {:d}"), "forty-two");
 
 reports a compile-time error for the same reason on compilers that support
-relaxed ``constexpr``.
+relaxed ``constexpr``. See `here <api.html#c.fmt>`_ for how to enable
+compile-time checks.
 
 The following code
 
@@ -129,7 +130,7 @@ 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.
 
-Compact binary code
+Compact Binary Code
 -------------------
 
 The library is designed to produce compact per-call compiled code. For example
@@ -174,8 +175,9 @@ 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
+These are available since GCC 4.8, Clang 3.0 and MSVC 19.0 (2015). 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.

doc/syntax.rst

@@ -76,7 +76,7 @@ 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 '}'>
+   fill: <a character other than '{', '}' or '\0'>
    align: "<" | ">" | "=" | "^"
    sign: "+" | "-" | " "
    width: `integer` | "{" `arg_id` "}"
@@ -84,11 +84,11 @@ The general form of a *standard format specifier* is:
    type: `int_type` | "a" | "A" | "c" | "e" | "E" | "f" | "F" | "g" | "G" | "p" | "s"
    int_type: "b" | "B" | "d" | "n" | "o" | "x" | "X"
 
-The *fill* character can be any character 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 *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 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.                                                   |
 +---------+----------------------------------------------------------+
@@ -154,9 +149,11 @@ conversions, trailing zeros are not removed from the result.
 *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
@@ -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 +261,19 @@ 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'``.                                     |
+| ``'n'`` | Number. This is the same as ``'g'``, except that it uses |
+|         | the current locale setting to insert the appropriate     |
+|         | number separator characters.                             |
++---------+----------------------------------------------------------+
+| ``'%'`` | Fixed point as a percentage. This is similar to ``'f'``, |
+|         | but the argument is multiplied by 100 and a percent sign |
+|         | ``%`` is appended.                                       |
++---------+----------------------------------------------------------+
+| 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 +309,7 @@ The available presentation types for pointers are:
 
 .. _formatexamples:
 
-Format examples
+Format Examples
 ===============
 
 This section contains examples of the format syntax and comparison with
@@ -357,6 +363,13 @@ Replacing ``%+f``, ``%-f``, and ``% f`` and specifying a sign::
    format("{:-f}; {:-f}", 3.14, -3.14);  // show only the minus -- same as '{:f}; {:f}'
    // Result: "3.140000; -3.140000"
 
+As a percentage::
+
+   format("{0:f} or {0:%}", .635);
+   // Result: "0.635000 or 63.500000%"
+   format("{:*^{}.{}%}", 1., 15, 2); // With fill, dynamic width and dynamic precision.
+   // Result: "****100.00%****"
+
 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);
@@ -412,4 +425,3 @@ 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.
 
@@ -45,7 +39,7 @@ You can control generation of the make ``test`` target with the ``FMT_TEST``
 CMake option. This can be useful if you include fmt as a subdirectory in
 your project but don't want to add fmt's tests to your ``test`` target.
 
-If you use Windows and have Visual Studio installed, a :file:`FORMAT.sln`
+If you use Windows and have Visual Studio installed, a :file:`FMT.sln`
 file and several :file:`.vcproj` files will be created. You can then build them
 using Visual Studio or msbuild.
 
@@ -58,8 +52,14 @@ 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
-============================
+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::
@@ -74,11 +74,16 @@ or
 
 to exclude it from ``make``, ``make all``, or ``cmake --build .``.
 
-Settting up your target to use a header-only version of ``fmt`` is equaly easy::
+You can detect and use an installed version of {fmt} as follows::
 
-   target_link_libraries(<your-target> PRIVATE fmt-header-only)
+   find_package(fmt)
+   target_link_libraries(<your-target> fmt::fmt)
 
-Building the documentation
+Setting up your target to use a header-only version of ``fmt`` is equally easy::
+
+   target_link_libraries(<your-target> PRIVATE fmt::fmt-header-only)
+
+Building the Documentation
 ==========================
 
 To build the documentation you need the following software installed on your

include/fmt/chrono.h

@@ -0,0 +1,828 @@
+// Formatting library for C++ - chrono support
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_CHRONO_H_
+#define FMT_CHRONO_H_
+
+#include "format.h"
+#include "locale.h"
+
+#include <chrono>
+#include <ctime>
+#include <locale>
+#include <sstream>
+
+// enable safe chrono durations, unless explicitly disabled
+#ifndef FMT_SAFE_DURATION_CAST
+#  define FMT_SAFE_DURATION_CAST 1
+#endif
+
+#if FMT_SAFE_DURATION_CAST
+#  include "safe-duration-cast.h"
+#endif
+
+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 != nullptr; }
+
+    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 != nullptr;
+    }
+#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 != nullptr; }
+
+    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 != nullptr;
+    }
+#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);
+}
+}  // namespace internal
+
+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;
+};
+
+namespace internal {
+template <typename Period> FMT_CONSTEXPR const char* get_units() {
+  return nullptr;
+}
+template <> FMT_CONSTEXPR const char* get_units<std::atto>() { return "as"; }
+template <> FMT_CONSTEXPR const char* get_units<std::femto>() { return "fs"; }
+template <> FMT_CONSTEXPR const char* get_units<std::pico>() { return "ps"; }
+template <> FMT_CONSTEXPR const char* get_units<std::nano>() { return "ns"; }
+template <> FMT_CONSTEXPR const char* get_units<std::micro>() { return "µs"; }
+template <> FMT_CONSTEXPR const char* get_units<std::milli>() { return "ms"; }
+template <> FMT_CONSTEXPR const char* get_units<std::centi>() { return "cs"; }
+template <> FMT_CONSTEXPR const char* get_units<std::deci>() { return "ds"; }
+template <> FMT_CONSTEXPR const char* get_units<std::ratio<1>>() { return "s"; }
+template <> FMT_CONSTEXPR const char* get_units<std::deca>() { return "das"; }
+template <> FMT_CONSTEXPR const char* get_units<std::hecto>() { return "hs"; }
+template <> FMT_CONSTEXPR const char* get_units<std::kilo>() { return "ks"; }
+template <> FMT_CONSTEXPR const char* get_units<std::mega>() { return "Ms"; }
+template <> FMT_CONSTEXPR const char* get_units<std::giga>() { return "Gs"; }
+template <> FMT_CONSTEXPR const char* get_units<std::tera>() { return "Ts"; }
+template <> FMT_CONSTEXPR const char* get_units<std::peta>() { return "Ps"; }
+template <> FMT_CONSTEXPR const char* get_units<std::exa>() { return "Es"; }
+template <> FMT_CONSTEXPR const char* get_units<std::ratio<60>>() {
+  return "m";
+}
+template <> FMT_CONSTEXPR const char* get_units<std::ratio<3600>>() {
+  return "h";
+}
+
+enum class numeric_system {
+  standard,
+  // Alternative numeric system, e.g. 十二 instead of 12 in ja_JP locale.
+  alternative
+};
+
+// Parses a put_time-like format string and invokes handler actions.
+template <typename Char, typename Handler>
+FMT_CONSTEXPR const Char* parse_chrono_format(const Char* begin,
+                                              const Char* end,
+                                              Handler&& handler) {
+  auto ptr = begin;
+  while (ptr != end) {
+    auto c = *ptr;
+    if (c == '}') break;
+    if (c != '%') {
+      ++ptr;
+      continue;
+    }
+    if (begin != ptr) handler.on_text(begin, ptr);
+    ++ptr;  // consume '%'
+    if (ptr == end) FMT_THROW(format_error("invalid format"));
+    c = *ptr++;
+    switch (c) {
+    case '%':
+      handler.on_text(ptr - 1, ptr);
+      break;
+    case 'n': {
+      const char newline[] = "\n";
+      handler.on_text(newline, newline + 1);
+      break;
+    }
+    case 't': {
+      const char tab[] = "\t";
+      handler.on_text(tab, tab + 1);
+      break;
+    }
+    // Day of the week:
+    case 'a':
+      handler.on_abbr_weekday();
+      break;
+    case 'A':
+      handler.on_full_weekday();
+      break;
+    case 'w':
+      handler.on_dec0_weekday(numeric_system::standard);
+      break;
+    case 'u':
+      handler.on_dec1_weekday(numeric_system::standard);
+      break;
+    // Month:
+    case 'b':
+      handler.on_abbr_month();
+      break;
+    case 'B':
+      handler.on_full_month();
+      break;
+    // Hour, minute, second:
+    case 'H':
+      handler.on_24_hour(numeric_system::standard);
+      break;
+    case 'I':
+      handler.on_12_hour(numeric_system::standard);
+      break;
+    case 'M':
+      handler.on_minute(numeric_system::standard);
+      break;
+    case 'S':
+      handler.on_second(numeric_system::standard);
+      break;
+    // Other:
+    case 'c':
+      handler.on_datetime(numeric_system::standard);
+      break;
+    case 'x':
+      handler.on_loc_date(numeric_system::standard);
+      break;
+    case 'X':
+      handler.on_loc_time(numeric_system::standard);
+      break;
+    case 'D':
+      handler.on_us_date();
+      break;
+    case 'F':
+      handler.on_iso_date();
+      break;
+    case 'r':
+      handler.on_12_hour_time();
+      break;
+    case 'R':
+      handler.on_24_hour_time();
+      break;
+    case 'T':
+      handler.on_iso_time();
+      break;
+    case 'p':
+      handler.on_am_pm();
+      break;
+    case 'Q':
+      handler.on_duration_value();
+      break;
+    case 'q':
+      handler.on_duration_unit();
+      break;
+    case 'z':
+      handler.on_utc_offset();
+      break;
+    case 'Z':
+      handler.on_tz_name();
+      break;
+    // Alternative representation:
+    case 'E': {
+      if (ptr == end) FMT_THROW(format_error("invalid format"));
+      c = *ptr++;
+      switch (c) {
+      case 'c':
+        handler.on_datetime(numeric_system::alternative);
+        break;
+      case 'x':
+        handler.on_loc_date(numeric_system::alternative);
+        break;
+      case 'X':
+        handler.on_loc_time(numeric_system::alternative);
+        break;
+      default:
+        FMT_THROW(format_error("invalid format"));
+      }
+      break;
+    }
+    case 'O':
+      if (ptr == end) FMT_THROW(format_error("invalid format"));
+      c = *ptr++;
+      switch (c) {
+      case 'w':
+        handler.on_dec0_weekday(numeric_system::alternative);
+        break;
+      case 'u':
+        handler.on_dec1_weekday(numeric_system::alternative);
+        break;
+      case 'H':
+        handler.on_24_hour(numeric_system::alternative);
+        break;
+      case 'I':
+        handler.on_12_hour(numeric_system::alternative);
+        break;
+      case 'M':
+        handler.on_minute(numeric_system::alternative);
+        break;
+      case 'S':
+        handler.on_second(numeric_system::alternative);
+        break;
+      default:
+        FMT_THROW(format_error("invalid format"));
+      }
+      break;
+    default:
+      FMT_THROW(format_error("invalid format"));
+    }
+    begin = ptr;
+  }
+  if (begin != ptr) handler.on_text(begin, ptr);
+  return ptr;
+}
+
+struct chrono_format_checker {
+  FMT_NORETURN void report_no_date() { FMT_THROW(format_error("no date")); }
+
+  template <typename Char> void on_text(const Char*, const Char*) {}
+  FMT_NORETURN void on_abbr_weekday() { report_no_date(); }
+  FMT_NORETURN void on_full_weekday() { report_no_date(); }
+  FMT_NORETURN void on_dec0_weekday(numeric_system) { report_no_date(); }
+  FMT_NORETURN void on_dec1_weekday(numeric_system) { report_no_date(); }
+  FMT_NORETURN void on_abbr_month() { report_no_date(); }
+  FMT_NORETURN void on_full_month() { report_no_date(); }
+  void on_24_hour(numeric_system) {}
+  void on_12_hour(numeric_system) {}
+  void on_minute(numeric_system) {}
+  void on_second(numeric_system) {}
+  FMT_NORETURN void on_datetime(numeric_system) { report_no_date(); }
+  FMT_NORETURN void on_loc_date(numeric_system) { report_no_date(); }
+  FMT_NORETURN void on_loc_time(numeric_system) { report_no_date(); }
+  FMT_NORETURN void on_us_date() { report_no_date(); }
+  FMT_NORETURN void on_iso_date() { report_no_date(); }
+  void on_12_hour_time() {}
+  void on_24_hour_time() {}
+  void on_iso_time() {}
+  void on_am_pm() {}
+  void on_duration_value() {}
+  void on_duration_unit() {}
+  FMT_NORETURN void on_utc_offset() { report_no_date(); }
+  FMT_NORETURN void on_tz_name() { report_no_date(); }
+};
+
+template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+inline bool isnan(T) {
+  return false;
+}
+template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
+inline bool isnan(T value) {
+  return std::isnan(value);
+}
+
+template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+inline bool isfinite(T) {
+  return true;
+}
+template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
+inline bool isfinite(T value) {
+  return std::isfinite(value);
+}
+
+// Converts value to int and checks that it's in the range [0, upper).
+template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+inline int to_nonnegative_int(T value, int upper) {
+  FMT_ASSERT(value >= 0 && value <= upper, "invalid value");
+  (void)upper;
+  return static_cast<int>(value);
+}
+template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
+inline int to_nonnegative_int(T value, int upper) {
+  FMT_ASSERT(
+      std::isnan(value) || (value >= 0 && value <= static_cast<T>(upper)),
+      "invalid value");
+  (void)upper;
+  return static_cast<int>(value);
+}
+
+template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+inline T mod(T x, int y) {
+  return x % y;
+}
+template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
+inline T mod(T x, int y) {
+  return std::fmod(x, static_cast<T>(y));
+}
+
+// If T is an integral type, maps T to its unsigned counterpart, otherwise
+// leaves it unchanged (unlike std::make_unsigned).
+template <typename T, bool INTEGRAL = std::is_integral<T>::value>
+struct make_unsigned_or_unchanged {
+  using type = T;
+};
+
+template <typename T> struct make_unsigned_or_unchanged<T, true> {
+  using type = typename std::make_unsigned<T>::type;
+};
+
+#if FMT_SAFE_DURATION_CAST
+// throwing version of safe_duration_cast
+template <typename To, typename FromRep, typename FromPeriod>
+To fmt_safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from) {
+  int ec;
+  To to = safe_duration_cast::safe_duration_cast<To>(from, ec);
+  if (ec) FMT_THROW(format_error("cannot format duration"));
+  return to;
+}
+#endif
+
+template <typename Rep, typename Period,
+          FMT_ENABLE_IF(std::is_integral<Rep>::value)>
+inline std::chrono::duration<Rep, std::milli> get_milliseconds(
+    std::chrono::duration<Rep, Period> d) {
+  // this may overflow and/or the result may not fit in the
+  // target type.
+#if FMT_SAFE_DURATION_CAST
+  using CommonSecondsType =
+      typename std::common_type<decltype(d), std::chrono::seconds>::type;
+  const auto d_as_common = fmt_safe_duration_cast<CommonSecondsType>(d);
+  const auto d_as_whole_seconds =
+      fmt_safe_duration_cast<std::chrono::seconds>(d_as_common);
+  // this conversion should be nonproblematic
+  const auto diff = d_as_common - d_as_whole_seconds;
+  const auto ms =
+      fmt_safe_duration_cast<std::chrono::duration<Rep, std::milli>>(diff);
+  return ms;
+#else
+  auto s = std::chrono::duration_cast<std::chrono::seconds>(d);
+  return std::chrono::duration_cast<std::chrono::milliseconds>(d - s);
+#endif
+}
+
+template <typename Rep, typename Period,
+          FMT_ENABLE_IF(std::is_floating_point<Rep>::value)>
+inline std::chrono::duration<Rep, std::milli> get_milliseconds(
+    std::chrono::duration<Rep, Period> d) {
+  using common_type = typename std::common_type<Rep, std::intmax_t>::type;
+  auto ms = mod(d.count() * static_cast<common_type>(Period::num) /
+                    static_cast<common_type>(Period::den) * 1000,
+                1000);
+  return std::chrono::duration<Rep, std::milli>(static_cast<Rep>(ms));
+}
+
+template <typename Rep, typename OutputIt>
+OutputIt format_chrono_duration_value(OutputIt out, Rep val, int precision) {
+  if (precision >= 0) return format_to(out, "{:.{}f}", val, precision);
+  return format_to(out, std::is_floating_point<Rep>::value ? "{:g}" : "{}",
+                   val);
+}
+
+template <typename Period, typename OutputIt>
+static OutputIt format_chrono_duration_unit(OutputIt out) {
+  if (const char* unit = get_units<Period>()) return format_to(out, "{}", unit);
+  if (Period::den == 1) return format_to(out, "[{}]s", Period::num);
+  return format_to(out, "[{}/{}]s", Period::num, Period::den);
+}
+
+template <typename FormatContext, typename OutputIt, typename Rep,
+          typename Period>
+struct chrono_formatter {
+  FormatContext& context;
+  OutputIt out;
+  int precision;
+  // rep is unsigned to avoid overflow.
+  using rep =
+      conditional_t<std::is_integral<Rep>::value && sizeof(Rep) < sizeof(int),
+                    unsigned, typename make_unsigned_or_unchanged<Rep>::type>;
+  rep val;
+  using seconds = std::chrono::duration<rep>;
+  seconds s;
+  using milliseconds = std::chrono::duration<rep, std::milli>;
+  bool negative;
+
+  using char_type = typename FormatContext::char_type;
+
+  explicit chrono_formatter(FormatContext& ctx, OutputIt o,
+                            std::chrono::duration<Rep, Period> d)
+      : context(ctx), out(o), val(d.count()), negative(false) {
+    if (d.count() < 0) {
+      val = 0 - val;
+      negative = true;
+    }
+
+    // this may overflow and/or the result may not fit in the
+    // target type.
+#if FMT_SAFE_DURATION_CAST
+    // might need checked conversion (rep!=Rep)
+    auto tmpval = std::chrono::duration<rep, Period>(val);
+    s = fmt_safe_duration_cast<seconds>(tmpval);
+#else
+    s = std::chrono::duration_cast<seconds>(
+        std::chrono::duration<rep, Period>(val));
+#endif
+  }
+
+  // returns true if nan or inf, writes to out.
+  bool handle_nan_inf() {
+    if (isfinite(val)) {
+      return false;
+    }
+    if (isnan(val)) {
+      write_nan();
+      return true;
+    }
+    // must be +-inf
+    if (val > 0) {
+      write_pinf();
+    } else {
+      write_ninf();
+    }
+    return true;
+  }
+
+  Rep hour() const { return static_cast<Rep>(mod((s.count() / 3600), 24)); }
+
+  Rep hour12() const {
+    Rep hour = static_cast<Rep>(mod((s.count() / 3600), 12));
+    return hour <= 0 ? 12 : hour;
+  }
+
+  Rep minute() const { return static_cast<Rep>(mod((s.count() / 60), 60)); }
+  Rep second() const { return static_cast<Rep>(mod(s.count(), 60)); }
+
+  std::tm time() const {
+    auto time = std::tm();
+    time.tm_hour = to_nonnegative_int(hour(), 24);
+    time.tm_min = to_nonnegative_int(minute(), 60);
+    time.tm_sec = to_nonnegative_int(second(), 60);
+    return time;
+  }
+
+  void write_sign() {
+    if (negative) {
+      *out++ = '-';
+      negative = false;
+    }
+  }
+
+  void write(Rep value, int width) {
+    write_sign();
+    if (isnan(value)) return write_nan();
+    uint32_or_64_or_128_t<int> n = to_unsigned(
+        to_nonnegative_int(value, max_value<int>()));
+    int num_digits = internal::count_digits(n);
+    if (width > num_digits) out = std::fill_n(out, width - num_digits, '0');
+    out = format_decimal<char_type>(out, n, num_digits);
+  }
+
+  void write_nan() { std::copy_n("nan", 3, out); }
+  void write_pinf() { std::copy_n("inf", 3, out); }
+  void write_ninf() { std::copy_n("-inf", 4, out); }
+
+  void format_localized(const tm& time, const char* format) {
+    if (isnan(val)) return write_nan();
+    auto locale = context.locale().template get<std::locale>();
+    auto& facet = std::use_facet<std::time_put<char_type>>(locale);
+    std::basic_ostringstream<char_type> os;
+    os.imbue(locale);
+    facet.put(os, os, ' ', &time, format, format + std::strlen(format));
+    auto str = os.str();
+    std::copy(str.begin(), str.end(), out);
+  }
+
+  void on_text(const char_type* begin, const char_type* end) {
+    std::copy(begin, end, out);
+  }
+
+  // These are not implemented because durations don't have date information.
+  void on_abbr_weekday() {}
+  void on_full_weekday() {}
+  void on_dec0_weekday(numeric_system) {}
+  void on_dec1_weekday(numeric_system) {}
+  void on_abbr_month() {}
+  void on_full_month() {}
+  void on_datetime(numeric_system) {}
+  void on_loc_date(numeric_system) {}
+  void on_loc_time(numeric_system) {}
+  void on_us_date() {}
+  void on_iso_date() {}
+  void on_utc_offset() {}
+  void on_tz_name() {}
+
+  void on_24_hour(numeric_system ns) {
+    if (handle_nan_inf()) return;
+
+    if (ns == numeric_system::standard) return write(hour(), 2);
+    auto time = tm();
+    time.tm_hour = to_nonnegative_int(hour(), 24);
+    format_localized(time, "%OH");
+  }
+
+  void on_12_hour(numeric_system ns) {
+    if (handle_nan_inf()) return;
+
+    if (ns == numeric_system::standard) return write(hour12(), 2);
+    auto time = tm();
+    time.tm_hour = to_nonnegative_int(hour12(), 12);
+    format_localized(time, "%OI");
+  }
+
+  void on_minute(numeric_system ns) {
+    if (handle_nan_inf()) return;
+
+    if (ns == numeric_system::standard) return write(minute(), 2);
+    auto time = tm();
+    time.tm_min = to_nonnegative_int(minute(), 60);
+    format_localized(time, "%OM");
+  }
+
+  void on_second(numeric_system ns) {
+    if (handle_nan_inf()) return;
+
+    if (ns == numeric_system::standard) {
+      write(second(), 2);
+#if FMT_SAFE_DURATION_CAST
+      // convert rep->Rep
+      using duration_rep = std::chrono::duration<rep, Period>;
+      using duration_Rep = std::chrono::duration<Rep, Period>;
+      auto tmpval = fmt_safe_duration_cast<duration_Rep>(duration_rep{val});
+#else
+      auto tmpval = std::chrono::duration<Rep, Period>(val);
+#endif
+      auto ms = get_milliseconds(tmpval);
+      if (ms != std::chrono::milliseconds(0)) {
+        *out++ = '.';
+        write(ms.count(), 3);
+      }
+      return;
+    }
+    auto time = tm();
+    time.tm_sec = to_nonnegative_int(second(), 60);
+    format_localized(time, "%OS");
+  }
+
+  void on_12_hour_time() {
+    if (handle_nan_inf()) return;
+
+    format_localized(time(), "%r");
+  }
+
+  void on_24_hour_time() {
+    if (handle_nan_inf()) {
+      *out++ = ':';
+      handle_nan_inf();
+      return;
+    }
+
+    write(hour(), 2);
+    *out++ = ':';
+    write(minute(), 2);
+  }
+
+  void on_iso_time() {
+    on_24_hour_time();
+    *out++ = ':';
+    if (handle_nan_inf()) return;
+    write(second(), 2);
+  }
+
+  void on_am_pm() {
+    if (handle_nan_inf()) return;
+    format_localized(time(), "%p");
+  }
+
+  void on_duration_value() {
+    if (handle_nan_inf()) return;
+    write_sign();
+    out = format_chrono_duration_value(out, val, precision);
+  }
+
+  void on_duration_unit() { out = format_chrono_duration_unit<Period>(out); }
+};
+}  // namespace internal
+
+template <typename Rep, typename Period, typename Char>
+struct formatter<std::chrono::duration<Rep, Period>, Char> {
+ private:
+  basic_format_specs<Char> specs;
+  int precision;
+  using arg_ref_type = internal::arg_ref<Char>;
+  arg_ref_type width_ref;
+  arg_ref_type precision_ref;
+  mutable basic_string_view<Char> format_str;
+  using duration = std::chrono::duration<Rep, Period>;
+
+  struct spec_handler {
+    formatter& f;
+    basic_parse_context<Char>& context;
+    basic_string_view<Char> format_str;
+
+    template <typename Id> FMT_CONSTEXPR arg_ref_type make_arg_ref(Id arg_id) {
+      context.check_arg_id(arg_id);
+      return arg_ref_type(arg_id);
+    }
+
+    FMT_CONSTEXPR arg_ref_type make_arg_ref(basic_string_view<Char> arg_id) {
+      context.check_arg_id(arg_id);
+      return arg_ref_type(arg_id);
+    }
+
+    FMT_CONSTEXPR arg_ref_type make_arg_ref(internal::auto_id) {
+      return arg_ref_type(context.next_arg_id());
+    }
+
+    void on_error(const char* msg) { FMT_THROW(format_error(msg)); }
+    void on_fill(Char fill) { f.specs.fill[0] = fill; }
+    void on_align(align_t align) { f.specs.align = align; }
+    void on_width(unsigned width) { f.specs.width = width; }
+    void on_precision(unsigned _precision) { f.precision = _precision; }
+    void end_precision() {}
+
+    template <typename Id> void on_dynamic_width(Id arg_id) {
+      f.width_ref = make_arg_ref(arg_id);
+    }
+
+    template <typename Id> void on_dynamic_precision(Id arg_id) {
+      f.precision_ref = make_arg_ref(arg_id);
+    }
+  };
+
+  using iterator = typename basic_parse_context<Char>::iterator;
+  struct parse_range {
+    iterator begin;
+    iterator end;
+  };
+
+  FMT_CONSTEXPR parse_range do_parse(basic_parse_context<Char>& ctx) {
+    auto begin = ctx.begin(), end = ctx.end();
+    if (begin == end || *begin == '}') return {begin, begin};
+    spec_handler handler{*this, ctx, format_str};
+    begin = internal::parse_align(begin, end, handler);
+    if (begin == end) return {begin, begin};
+    begin = internal::parse_width(begin, end, handler);
+    if (begin == end) return {begin, begin};
+    if (*begin == '.') {
+      if (std::is_floating_point<Rep>::value)
+        begin = internal::parse_precision(begin, end, handler);
+      else
+        handler.on_error("precision not allowed for this argument type");
+    }
+    end = parse_chrono_format(begin, end, internal::chrono_format_checker());
+    return {begin, end};
+  }
+
+ public:
+  formatter() : precision(-1) {}
+
+  FMT_CONSTEXPR auto parse(basic_parse_context<Char>& ctx)
+      -> decltype(ctx.begin()) {
+    auto range = do_parse(ctx);
+    format_str = basic_string_view<Char>(
+        &*range.begin, internal::to_unsigned(range.end - range.begin));
+    return range.end;
+  }
+
+  template <typename FormatContext>
+  auto format(const duration& d, FormatContext& ctx) -> decltype(ctx.out()) {
+    auto begin = format_str.begin(), end = format_str.end();
+    // As a possible future optimization, we could avoid extra copying if width
+    // is not specified.
+    basic_memory_buffer<Char> buf;
+    auto out = std::back_inserter(buf);
+    using range = internal::output_range<decltype(ctx.out()), Char>;
+    internal::basic_writer<range> w(range(ctx.out()));
+    internal::handle_dynamic_spec<internal::width_checker>(specs.width,
+                                                           width_ref, ctx);
+    internal::handle_dynamic_spec<internal::precision_checker>(
+        precision, precision_ref, ctx);
+    if (begin == end || *begin == '}') {
+      out = internal::format_chrono_duration_value(out, d.count(), precision);
+      internal::format_chrono_duration_unit<Period>(out);
+    } else {
+      internal::chrono_formatter<FormatContext, decltype(out), Rep, Period> f(
+          ctx, out, d);
+      f.precision = precision;
+      parse_chrono_format(begin, end, f);
+    }
+    w.write(buf.data(), buf.size(), specs);
+    return w.out();
+  }
+};
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_CHRONO_H_

include/fmt/color.h

@@ -0,0 +1,586 @@
+// Formatting library for C++ - color support
+//
+// Copyright (c) 2018 - present, Victor Zverovich and fmt contributors
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_COLOR_H_
+#define FMT_COLOR_H_
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+
+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
+
+enum class terminal_color : uint8_t {
+  black = 30,
+  red,
+  green,
+  yellow,
+  blue,
+  magenta,
+  cyan,
+  white,
+  bright_black = 90,
+  bright_red,
+  bright_green,
+  bright_yellow,
+  bright_blue,
+  bright_magenta,
+  bright_cyan,
+  bright_white
+};
+
+enum class emphasis : uint8_t {
+  bold = 1,
+  italic = 1 << 1,
+  underline = 1 << 2,
+  strikethrough = 1 << 3
+};
+
+// rgb is a struct for red, green and blue colors.
+// Using the name "rgb" makes some editors show the color in a tooltip.
+struct rgb {
+  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 {
+
+// 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{} {
+    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(terminal_color term_color) FMT_NOEXCEPT : is_rgb(),
+                                                                     value{} {
+    value.term_color = static_cast<uint8_t>(term_color);
+  }
+  bool is_rgb;
+  union color_union {
+    uint8_t term_color;
+    uint32_t rgb_color;
+  } value;
+};
+}  // namespace internal
+
+// 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) {}
+
+  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)
+        FMT_THROW(format_error("can't OR a terminal color"));
+      foreground_color.value.rgb_color |= rhs.foreground_color.value.rgb_color;
+    }
+
+    if (!set_background_color) {
+      set_background_color = rhs.set_background_color;
+      background_color = rhs.background_color;
+    } else if (rhs.set_background_color) {
+      if (!background_color.is_rgb || !rhs.background_color.is_rgb)
+        FMT_THROW(format_error("can't OR a terminal color"));
+      background_color.value.rgb_color |= rhs.background_color.value.rgb_color;
+    }
+
+    ems = static_cast<emphasis>(static_cast<uint8_t>(ems) |
+                                static_cast<uint8_t>(rhs.ems));
+    return *this;
+  }
+
+  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) {
+    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)
+        FMT_THROW(format_error("can't AND a terminal color"));
+      foreground_color.value.rgb_color &= rhs.foreground_color.value.rgb_color;
+    }
+
+    if (!set_background_color) {
+      set_background_color = rhs.set_background_color;
+      background_color = rhs.background_color;
+    } else if (rhs.set_background_color) {
+      if (!background_color.is_rgb || !rhs.background_color.is_rgb)
+        FMT_THROW(format_error("can't AND a terminal color"));
+      background_color.value.rgb_color &= rhs.background_color.value.rgb_color;
+    }
+
+    ems = static_cast<emphasis>(static_cast<uint8_t>(ems) &
+                                static_cast<uint8_t>(rhs.ems));
+    return *this;
+  }
+
+  friend FMT_CONSTEXPR text_style operator&(text_style lhs,
+                                            const text_style& rhs) {
+    return lhs &= rhs;
+  }
+
+  FMT_CONSTEXPR bool has_foreground() const FMT_NOEXCEPT {
+    return set_foreground_color;
+  }
+  FMT_CONSTEXPR bool has_background() const FMT_NOEXCEPT {
+    return set_background_color;
+  }
+  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");
+    return foreground_color;
+  }
+  FMT_CONSTEXPR internal::color_type get_background() const FMT_NOEXCEPT {
+    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");
+    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;
+    }
+  }
+
+  friend FMT_CONSTEXPR_DECL text_style fg(internal::color_type foreground)
+      FMT_NOEXCEPT;
+  friend FMT_CONSTEXPR_DECL text_style bg(internal::color_type background)
+      FMT_NOEXCEPT;
+
+  internal::color_type foreground_color;
+  internal::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 {
+  return text_style(/*is_foreground=*/true, foreground);
+}
+
+FMT_CONSTEXPR text_style bg(internal::color_type background) FMT_NOEXCEPT {
+  return text_style(/*is_foreground=*/false, background);
+}
+
+FMT_CONSTEXPR text_style operator|(emphasis lhs, emphasis rhs) FMT_NOEXCEPT {
+  return text_style(lhs) | rhs;
+}
+
+namespace internal {
+
+template <typename Char> struct ansi_color_escape {
+  FMT_CONSTEXPR ansi_color_escape(internal::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;
+      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;
+
+      std::size_t index = 0;
+      buffer[index++] = static_cast<Char>('\x1b');
+      buffer[index++] = static_cast<Char>('[');
+
+      if (value >= 100u) {
+        buffer[index++] = static_cast<Char>('1');
+        value %= 100u;
+      }
+      buffer[index++] = static_cast<Char>('0' + value / 10u);
+      buffer[index++] = static_cast<Char>('0' + value % 10u);
+
+      buffer[index++] = static_cast<Char>('m');
+      buffer[index++] = static_cast<Char>('\0');
+      return;
+    }
+
+    for (int i = 0; i < 7; i++) {
+      buffer[i] = static_cast<Char>(esc[i]);
+    }
+    rgb color(text_color.value.rgb_color);
+    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);
+  }
+  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::strikethrough))
+      em_codes[3] = 9;
+
+    std::size_t index = 0;
+    for (int i = 0; i < 4; ++i) {
+      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]);
+      buffer[index++] = static_cast<Char>('m');
+    }
+    buffer[index++] = static_cast<Char>(0);
+  }
+  FMT_CONSTEXPR operator const Char*() const FMT_NOEXCEPT { return buffer; }
+
+  FMT_CONSTEXPR const Char* begin() const FMT_NOEXCEPT { return buffer; }
+  FMT_CONSTEXPR const Char* end() const FMT_NOEXCEPT {
+    return buffer + std::strlen(buffer);
+  }
+
+ private:
+  Char buffer[7u + 3u * 4u + 1u];
+
+  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);
+    out[2] = static_cast<Char>('0' + c % 10);
+    out[3] = static_cast<Char>(delimiter);
+  }
+};
+
+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);
+}
+
+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);
+}
+
+template <typename Char>
+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 {
+  std::fputs(chars, stream);
+}
+
+template <>
+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(internal::data::reset_color, stream);
+}
+
+template <> inline void reset_color<wchar_t>(FILE* stream) FMT_NOEXCEPT {
+  fputs(internal::data::wreset_color, stream);
+}
+
+template <typename Char>
+inline void reset_color(basic_memory_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 <typename Char>
+std::basic_string<Char> vformat(const text_style& ts,
+                                basic_string_view<Char> format_str,
+                                basic_format_args<buffer_context<Char> > args) {
+  basic_memory_buffer<Char> buffer;
+  bool has_style = false;
+  if (ts.has_emphasis()) {
+    has_style = true;
+    ansi_color_escape<Char> escape = make_emphasis<Char>(ts.get_emphasis());
+    buffer.append(escape.begin(), escape.end());
+  }
+  if (ts.has_foreground()) {
+    has_style = true;
+    ansi_color_escape<Char> escape =
+        make_foreground_color<Char>(ts.get_foreground());
+    buffer.append(escape.begin(), escape.end());
+  }
+  if (ts.has_background()) {
+    has_style = true;
+    ansi_color_escape<Char> escape =
+        make_background_color<Char>(ts.get_background());
+    buffer.append(escape.begin(), escape.end());
+  }
+  internal::vformat_to(buffer, format_str, args);
+  if (has_style) {
+    reset_color<Char>(buffer);
+  }
+  return fmt::to_string(buffer);
+}
+}  // namespace internal
+
+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<Char> > args) {
+  bool has_style = false;
+  if (ts.has_emphasis()) {
+    has_style = true;
+    internal::fputs<Char>(internal::make_emphasis<Char>(ts.get_emphasis()), f);
+  }
+  if (ts.has_foreground()) {
+    has_style = true;
+    internal::fputs<Char>(
+        internal::make_foreground_color<Char>(ts.get_foreground()), f);
+  }
+  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);
+  }
+}
+
+/**
+  Formats a string and prints it to the specified file stream using ANSI
+  escape sequences to specify text formatting.
+  Example:
+    fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
+               "Elapsed time: {0:.2f} seconds", 1.23);
+ */
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(internal::is_string<S>::value)>
+void print(std::FILE* f, const text_style& ts, const S& format_str,
+           const Args&... args) {
+  internal::check_format_string<Args...>(format_str);
+  using context = buffer_context<char_t<S> >;
+  format_arg_store<context, Args...> as{args...};
+  vprint(f, ts, format_str, basic_format_args<context>(as));
+}
+
+/**
+  Formats a string and prints it to stdout using ANSI escape sequences to
+  specify text formatting.
+  Example:
+    fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
+               "Elapsed time: {0:.2f} seconds", 1.23);
+ */
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(internal::is_string<S>::value)>
+void print(const text_style& ts, const S& format_str, const Args&... args) {
+  return print(stdout, ts, format_str, args...);
+}
+
+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<Char> > args) {
+  return internal::vformat(ts, to_string_view(format_str), args);
+}
+
+/**
+  \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 internal::vformat(
+      ts, to_string_view(format_str),
+      {internal::make_args_checked<Args...>(format_str, args...)});
+}
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_COLOR_H_

include/fmt/compile.h

@@ -0,0 +1,581 @@
+// 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 internal {
+
+// 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 {
+    unsigned arg_index;
+    basic_string_view<Char> str;
+    replacement repl;
+
+    FMT_CONSTEXPR value(unsigned 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(unsigned 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 void on_arg_id() { ++num_parts; }
+  FMT_CONSTEXPR void on_arg_id(unsigned) { ++num_parts; }
+  FMT_CONSTEXPR void on_arg_id(basic_string_view<Char>) { ++num_parts; }
+
+  FMT_CONSTEXPR void on_replacement_field(const Char*) {}
+
+  FMT_CONSTEXPR const Char* on_format_specs(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_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 void on_arg_id() {
+    part_ = part::make_arg_index(parse_context_.next_arg_id());
+  }
+
+  FMT_CONSTEXPR void on_arg_id(unsigned id) {
+    parse_context_.check_arg_id(id);
+    part_ = part::make_arg_index(id);
+  }
+
+  FMT_CONSTEXPR void on_arg_id(basic_string_view<Char> id) {
+    part_ = part::make_arg_name(id);
+  }
+
+  FMT_CONSTEXPR void on_replacement_field(const Char* ptr) {
+    part_.arg_id_end = ptr;
+    handler_(part_);
+  }
+
+  FMT_CONSTEXPR const Char* on_format_specs(const Char* begin,
+                                            const Char* end) {
+    auto repl = typename part::replacement();
+    dynamic_specs_handler<basic_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 Range, typename Context, typename Id>
+void format_arg(basic_parse_context<typename Range::value_type>& parse_ctx,
+                Context& ctx, Id arg_id) {
+  ctx.advance_to(
+      visit_format_arg(arg_formatter<Range>(ctx, &parse_ctx), ctx.arg(arg_id)));
+}
+
+// vformat_to is defined in a subnamespace to prevent ADL.
+namespace cf {
+template <typename Context, typename Range, typename CompiledFormat>
+auto vformat_to(Range out, CompiledFormat& cf, basic_format_args<Context> args)
+    -> typename Context::iterator {
+  using char_type = typename Context::char_type;
+  basic_parse_context<char_type> parse_ctx(to_string_view(cf.format_str_));
+  Context ctx(out.begin(), 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);
+      internal::format_arg<Range>(parse_ctx, ctx, value.arg_index);
+      break;
+
+    case format_part_t::kind::arg_name:
+      advance_to(parse_ctx, part.arg_id_end);
+      internal::format_arg<Range>(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<Range>(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<internal::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>(
+            internal::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 Range, typename CompiledFormat>
+  friend auto cf::vformat_to(Range 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(const T& first, 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 Char> struct text {
+  basic_string_view<Char> data;
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  OutputIt format(OutputIt out, const Args&...) const {
+    // TODO: reserve
+    return copy_str<Char>(data.begin(), data.end(), out);
+  }
+};
+
+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, typename OutputIt, typename T,
+          std::enable_if_t<std::is_integral_v<T>, int> = 0>
+OutputIt format_default(OutputIt out, T value) {
+  // TODO: reserve
+  format_int fi(value);
+  return std::copy(fi.data(), fi.data() + fi.size(), out);
+}
+
+template <typename Char, typename OutputIt>
+OutputIt format_default(OutputIt out, Char value) {
+  *out++ = value;
+  return out;
+}
+
+template <typename Char, typename OutputIt>
+OutputIt format_default(OutputIt out, const Char* value) {
+  auto length = std::char_traits<Char>::length(value);
+  return copy_str<Char>(value, value + length, out);
+}
+
+// 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 format_default<Char>(out, arg);
+  }
+};
+
+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>
+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 != to_string_view(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;
+  }
+}
+
+// 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>;
+      if constexpr (std::is_same<type, int>::value) {
+        return parse_tail<Args, POS + 2, ID + 1>(field<char_type, type, ID>(),
+                                                 format_str);
+      } else {
+        return unknown_format();
+      }
+    } 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);
+    return parse_tail<Args, end, ID>(make_text(str, POS, end - POS),
+                                     format_str);
+  }
+}
+#endif  // __cpp_if_constexpr
+}  // namespace internal
+
+#if FMT_USE_CONSTEXPR
+#  ifdef __cpp_if_constexpr
+template <typename... Args, typename S,
+          FMT_ENABLE_IF(is_compile_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 internal::make_text(str, 0, 0);
+  } else {
+    constexpr auto result =
+        internal::compile_format_string<internal::type_list<Args...>, 0, 0>(
+            format_str);
+    if constexpr (std::is_same<remove_cvref_t<decltype(result)>,
+                               internal::unknown_format>()) {
+      return internal::compiled_format<S, Args...>(to_string_view(format_str));
+    } else {
+      return result;
+    }
+  }
+}
+
+template <typename CompiledFormat, typename... Args,
+          typename Char = typename CompiledFormat::char_type,
+          FMT_ENABLE_IF(!std::is_base_of<internal::basic_compiled_format,
+                                         CompiledFormat>::value)>
+std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
+  basic_memory_buffer<Char> buffer;
+  using range = buffer_range<Char>;
+  using context = buffer_context<Char>;
+  cf.format(std::back_inserter(buffer), args...);
+  return to_string(buffer);
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(!std::is_base_of<internal::basic_compiled_format,
+                                         CompiledFormat>::value)>
+OutputIt format_to(OutputIt out, const CompiledFormat& cf,
+                   const Args&... args) {
+  return cf.format(out, args...);
+}
+#  else
+template <typename... Args, typename S,
+          FMT_ENABLE_IF(is_compile_string<S>::value)>
+constexpr auto compile(S format_str) -> internal::compiled_format<S, Args...> {
+  return internal::compiled_format<S, Args...>(to_string_view(format_str));
+}
+#  endif  // __cpp_if_constexpr
+#endif    // FMT_USE_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])
+    -> internal::compiled_format<const Char*, Args...> {
+  return internal::compiled_format<const Char*, Args...>(
+      basic_string_view<Char>(format_str, N - 1));
+}
+
+template <typename CompiledFormat, typename... Args,
+          typename Char = typename CompiledFormat::char_type,
+          FMT_ENABLE_IF(std::is_base_of<internal::basic_compiled_format,
+                                        CompiledFormat>::value)>
+std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
+  basic_memory_buffer<Char> buffer;
+  using range = buffer_range<Char>;
+  using context = buffer_context<Char>;
+  internal::cf::vformat_to<context>(range(buffer), cf,
+                                    {make_format_args<context>(args...)});
+  return to_string(buffer);
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(std::is_base_of<internal::basic_compiled_format,
+                                        CompiledFormat>::value)>
+OutputIt format_to(OutputIt out, const CompiledFormat& cf,
+                   const Args&... args) {
+  using char_type = typename CompiledFormat::char_type;
+  using range = internal::output_range<OutputIt, char_type>;
+  using context = format_context_t<OutputIt, char_type>;
+  return internal::cf::vformat_to<context>(
+      range(out), cf, {make_format_args<context>(args...)});
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(internal::is_output_iterator<OutputIt>::value)>
+format_to_n_result<OutputIt> format_to_n(OutputIt out, size_t n,
+                                         const CompiledFormat& cf,
+                                         const Args&... args) {
+  auto it =
+      format_to(internal::truncating_iterator<OutputIt>(out, n), cf, args...);
+  return {it.base(), it.count()};
+}
+
+template <typename CompiledFormat, typename... Args>
+std::size_t formatted_size(const CompiledFormat& cf, const Args&... args) {
+  return format_to(
+             internal::counting_iterator<typename CompiledFormat::char_type>(),
+             cf, args...)
+      .count();
+}
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_COMPILE_H_

include/fmt/locale.h

@@ -0,0 +1,77 @@
+// Formatting library for C++ - std::locale support
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_LOCALE_H_
+#define FMT_LOCALE_H_
+
+#include <locale>
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+
+namespace internal {
+template <typename Char>
+typename buffer_context<Char>::iterator vformat_to(
+    const std::locale& loc, buffer<Char>& buf,
+    basic_string_view<Char> format_str,
+    basic_format_args<buffer_context<Char>> args) {
+  using range = buffer_range<Char>;
+  return vformat_to<arg_formatter<range>>(buf, to_string_view(format_str), args,
+                                          internal::locale_ref(loc));
+}
+
+template <typename Char>
+std::basic_string<Char> vformat(const std::locale& loc,
+                                basic_string_view<Char> format_str,
+                                basic_format_args<buffer_context<Char>> args) {
+  basic_memory_buffer<Char> buffer;
+  internal::vformat_to(loc, buffer, format_str, args);
+  return fmt::to_string(buffer);
+}
+}  // namespace internal
+
+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<buffer_context<Char>> args) {
+  return internal::vformat(loc, to_string_view(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 internal::vformat(
+      loc, to_string_view(format_str),
+      {internal::make_args_checked<Args...>(format_str, args...)});
+}
+
+template <typename S, typename OutputIt, typename... Args,
+          typename Char = enable_if_t<
+              internal::is_output_iterator<OutputIt>::value, char_t<S>>>
+inline OutputIt vformat_to(OutputIt out, const std::locale& loc,
+                           const S& format_str,
+                           format_args_t<OutputIt, Char> args) {
+  using range = internal::output_range<OutputIt, Char>;
+  return vformat_to<arg_formatter<range>>(
+      range(out), to_string_view(format_str), args, internal::locale_ref(loc));
+}
+
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(internal::is_output_iterator<OutputIt>::value&&
+                            internal::is_string<S>::value)>
+inline OutputIt format_to(OutputIt out, const std::locale& loc,
+                          const S& format_str, Args&&... args) {
+  internal::check_format_string<Args...>(format_str);
+  using context = format_context_t<OutputIt, char_t<S>>;
+  format_arg_store<context, Args...> as{args...};
+  return vformat_to(out, loc, to_string_view(format_str),
+                    basic_format_args<context>(as));
+}
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_LOCALE_H_

include/fmt/ostream.h

@@ -1,6 +1,6 @@
 // Formatting library for C++ - std::ostream support
 //
-// Copyright (c) 2012 - 2016, Victor Zverovich
+// Copyright (c) 2012 - present, Victor Zverovich
 // All rights reserved.
 //
 // For the license information refer to format.h.
@@ -8,22 +8,21 @@
 #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 <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
@@ -39,104 +38,87 @@ 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> {
+template <typename Char> struct test_stream : std::basic_ostream<Char> {
  private:
-  struct null;
   // Hide all operator<< from std::basic_ostream<Char>.
-  void operator<<(null);
+  void_t<> operator<<(null<>);
+  void_t<> operator<<(const Char*);
+
+  template <typename T, FMT_ENABLE_IF(std::is_convertible<T, int>::value &&
+                                      !std::is_enum<T>::value)>
+  void_t<> operator<<(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 {
+// 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:
-  // std::string operator<< is not considered user-defined because we handle strings
-  // specially.
-  static const bool value = result::value && !std::is_same<T, std::string>::value;
-};
-
-// 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>
-class convert_to_int<T, Char, true> {
- public:
-  static const bool value =
-    convert_to_int<T, Char, false>::value && !is_streamable<T, Char>::value;
+  static const bool value = result::value;
 };
 
 // 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(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) {
+  formatbuf<Char> format_buf(buf);
   std::basic_ostream<Char> output(&format_buf);
   output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
   output << value;
-  buffer.resize(buffer.size());
+  buf.resize(buf.size());
 }
 
-// Disable builtin formatting of enums and use operator<< instead.
-template <typename T>
-struct format_enum<T,
-    typename std::enable_if<std::is_enum<T>::value>::type> : std::false_type {};
-}  // namespace internal
-
 // 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>::type>
+struct fallback_formatter<T, Char, enable_if_t<is_streamable<T, Char>::value>>
     : formatter<basic_string_view<Char>, Char> {
-
   template <typename Context>
-  auto format(const T &value, Context &ctx) -> decltype(ctx.out()) {
+  auto format(const T& value, Context& ctx) -> decltype(ctx.out()) {
     basic_memory_buffer<Char> buffer;
-    internal::format_value(buffer, value);
+    format_value(buffer, value);
     basic_string_view<Char> str(buffer.data(), buffer.size());
-    formatter<basic_string_view<Char>, Char>::format(str, ctx);
-    return ctx.out();
+    return formatter<basic_string_view<Char>, Char>::format(str, ctx);
   }
 };
+}  // namespace internal
 
 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<Char>> args) {
   basic_memory_buffer<Char> buffer;
-  vformat_to(buffer, format_str, args);
+  internal::vformat_to(buffer, format_str, args);
   internal::write(os, buffer);
 }
+
 /**
   \rst
   Prints formatted data to the stream *os*.
@@ -146,16 +128,11 @@ inline void vprint(std::basic_ostream<Char> &os,
     fmt::print(cerr, "Don't {}!", "panic");
   \endrst
  */
-template <typename... Args>
-inline void print(std::ostream &os, string_view format_str,
-                  const Args & ... args) {
-  vprint<char>(os, format_str, make_format_args<format_context>(args...));
-}
-
-template <typename... Args>
-inline void print(std::wostream &os, wstring_view format_str,
-                  const Args & ... args) {
-  vprint<wchar_t>(os, format_str, make_format_args<wformat_context>(args...));
+template <typename S, typename... Args,
+          typename Char = enable_if_t<internal::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),
+         {internal::make_args_checked<Args...>(format_str, args...)});
 }
 FMT_END_NAMESPACE
 

include/fmt/posix.h

@@ -10,7 +10,7 @@
 
 #if defined(__MINGW32__) || defined(__CYGWIN__)
 // Workaround MinGW bug https://sourceforge.net/p/mingw/bugs/2024/.
-# undef __STRICT_ANSI__
+#  undef __STRICT_ANSI__
 #endif
 
 #include <errno.h>
@@ -22,42 +22,42 @@
 #include <cstddef>
 
 #if defined __APPLE__ || defined(__FreeBSD__)
-# include <xlocale.h>  // for LC_NUMERIC_MASK on OS X
+#  include <xlocale.h>  // for LC_NUMERIC_MASK on OS X
 #endif
 
 #include "format.h"
 
 #ifndef FMT_POSIX
-# if defined(_WIN32) && !defined(__MINGW32__)
+#  if defined(_WIN32) && !defined(__MINGW32__)
 // Fix warnings about deprecated symbols.
-#  define FMT_POSIX(call) _##call
-# else
-#  define FMT_POSIX(call) call
-# endif
+#    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)
+#  define FMT_POSIX_CALL(call) FMT_SYSTEM(call)
 #else
-# define FMT_SYSTEM(call) call
-# ifdef _WIN32
+#  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
+#    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)
+#  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)
+#  define FMT_RETRY_VAL(result, expression, error_result) result = (expression)
 #endif
 
 #define FMT_RETRY(result, expression) FMT_RETRY_VAL(result, expression, -1)
@@ -69,7 +69,7 @@ FMT_BEGIN_NAMESPACE
   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:
+  You can use one of the following type aliases for common character types:
 
   +---------------+-----------------------------+
   | Type          | Definition                  |
@@ -89,28 +89,27 @@ FMT_BEGIN_NAMESPACE
     format(std::string("{}"), 42);
   \endrst
  */
-template <typename Char>
-class basic_cstring_view {
+template <typename Char> class basic_cstring_view {
  private:
-  const Char *data_;
+  const Char* data_;
 
  public:
   /** Constructs a string reference object from a C string. */
-  basic_cstring_view(const Char *s) : data_(s) {}
+  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()) {}
+  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_; }
+  const Char* c_str() const { return data_; }
 };
 
-typedef basic_cstring_view<char> cstring_view;
-typedef basic_cstring_view<wchar_t> wcstring_view;
+using cstring_view = basic_cstring_view<char>;
+using wcstring_view = basic_cstring_view<wchar_t>;
 
 // An error code.
 class error_code {
@@ -126,78 +125,34 @@ class error_code {
 // A buffered file.
 class buffered_file {
  private:
-  FILE *file_;
+  FILE* file_;
 
   friend class file;
 
-  explicit buffered_file(FILE *f) : file_(f) {}
+  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) {}
+  buffered_file() FMT_NOEXCEPT : file_(nullptr) {}
 
   // Destroys the object closing the file it represents if any.
-  FMT_API ~buffered_file() FMT_DTOR_NOEXCEPT;
-
-#if !FMT_USE_RVALUE_REFERENCES
-  // Emulate a move constructor and a move assignment operator if rvalue
-  // references are not supported.
+  FMT_API ~buffered_file() FMT_NOEXCEPT;
 
  private:
-  // A proxy object to emulate a move constructor.
-  // It is private to make it impossible call operator Proxy directly.
-  struct Proxy {
-    FILE *file;
-  };
-
-public:
-  // A "move constructor" for moving from a temporary.
-  buffered_file(Proxy p) FMT_NOEXCEPT : file_(p.file) {}
-
-  // A "move constructor" for moving from an lvalue.
-  buffered_file(buffered_file &f) FMT_NOEXCEPT : file_(f.file_) {
-    f.file_ = FMT_NULL;
-  }
-
-  // A "move assignment operator" for moving from a temporary.
-  buffered_file &operator=(Proxy p) {
-    close();
-    file_ = p.file;
-    return *this;
-  }
-
-  // A "move assignment operator" for moving from an lvalue.
-  buffered_file &operator=(buffered_file &other) {
-    close();
-    file_ = other.file_;
-    other.file_ = FMT_NULL;
-    return *this;
-  }
-
-  // Returns a proxy object for moving from a temporary:
-  //   buffered_file file = buffered_file(...);
-  operator Proxy() FMT_NOEXCEPT {
-    Proxy p = {file_};
-    file_ = FMT_NULL;
-    return p;
-  }
-
-#else
- private:
-  FMT_DISALLOW_COPY_AND_ASSIGN(buffered_file);
+  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(buffered_file&& other) FMT_NOEXCEPT : file_(other.file_) {
+    other.file_ = nullptr;
   }
 
-  buffered_file& operator=(buffered_file &&other) {
+  buffered_file& operator=(buffered_file&& other) {
     close();
     file_ = other.file_;
-    other.file_ = FMT_NULL;
+    other.file_ = nullptr;
     return *this;
   }
-#endif
 
   // Opens a file.
   FMT_API buffered_file(cstring_view filename, cstring_view mode);
@@ -206,18 +161,18 @@ public:
   FMT_API void close();
 
   // Returns the pointer to a FILE object representing this file.
-  FILE *get() const FMT_NOEXCEPT { return 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;
+  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) {
+  inline void print(string_view format_str, const Args&... args) {
     vprint(format_str, make_format_args(args...));
   }
 };
@@ -238,9 +193,9 @@ class file {
  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.
+    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.
@@ -249,68 +204,22 @@ class file {
   // Opens a file and constructs a file object representing this file.
   FMT_API file(cstring_view path, int oflag);
 
-#if !FMT_USE_RVALUE_REFERENCES
-  // Emulate a move constructor and a move assignment operator if rvalue
-  // references are not supported.
-
  private:
-  // A proxy object to emulate a move constructor.
-  // It is private to make it impossible call operator Proxy directly.
-  struct Proxy {
-    int fd;
-  };
+  file(const file&) = delete;
+  void operator=(const file&) = delete;
 
  public:
-  // A "move constructor" for moving from a temporary.
-  file(Proxy p) FMT_NOEXCEPT : fd_(p.fd) {}
+  file(file&& other) FMT_NOEXCEPT : fd_(other.fd_) { other.fd_ = -1; }
 
-  // A "move constructor" for moving from an lvalue.
-  file(file &other) FMT_NOEXCEPT : fd_(other.fd_) {
-    other.fd_ = -1;
-  }
-
-  // A "move assignment operator" for moving from a temporary.
-  file &operator=(Proxy p) {
-    close();
-    fd_ = p.fd;
-    return *this;
-  }
-
-  // A "move assignment operator" for moving from an lvalue.
-  file &operator=(file &other) {
+  file& operator=(file&& other) {
     close();
     fd_ = other.fd_;
     other.fd_ = -1;
     return *this;
   }
 
-  // Returns a proxy object for moving from a temporary:
-  //   file f = file(...);
-  operator Proxy() FMT_NOEXCEPT {
-    Proxy p = {fd_};
-    fd_ = -1;
-    return p;
-  }
-
-#else
- private:
-  FMT_DISALLOW_COPY_AND_ASSIGN(file);
-
- 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;
-  }
-#endif
-
   // Destroys the object closing the file it represents if any.
-  FMT_API ~file() FMT_DTOR_NOEXCEPT;
+  FMT_API ~file() FMT_NOEXCEPT;
 
   // Returns the file descriptor.
   int descriptor() const FMT_NOEXCEPT { return fd_; }
@@ -323,10 +232,10 @@ class file {
   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);
+  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);
+  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.
@@ -338,66 +247,59 @@ class file {
 
   // 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;
+  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);
+  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);
+  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__)
-# define FMT_LOCALE
-#endif
-
 #ifdef FMT_LOCALE
 // A "C" numeric locale.
 class Locale {
  private:
-# ifdef _MSC_VER
-  typedef _locale_t locale_t;
+#  ifdef _WIN32
+  using locale_t = _locale_t;
 
   enum { LC_NUMERIC_MASK = LC_NUMERIC };
 
-  static locale_t newlocale(int category_mask, const char *locale, locale_t) {
+  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 void freelocale(locale_t locale) { _free_locale(locale); }
 
-  static double strtod_l(const char *nptr, char **endptr, _locale_t locale) {
+  static double strtod_l(const char* nptr, char** endptr, _locale_t locale) {
     return _strtod_l(nptr, endptr, locale);
   }
-# endif
+#  endif
 
   locale_t locale_;
 
-  FMT_DISALLOW_COPY_AND_ASSIGN(Locale);
+  Locale(const Locale&) = delete;
+  void operator=(const Locale&) = delete;
 
  public:
-  typedef locale_t Type;
+  using type = locale_t;
 
-  Locale() : locale_(newlocale(LC_NUMERIC_MASK, "C", FMT_NULL)) {
-    if (!locale_)
-      FMT_THROW(system_error(errno, "cannot create locale"));
+  Locale() : locale_(newlocale(LC_NUMERIC_MASK, "C", nullptr)) {
+    if (!locale_) FMT_THROW(system_error(errno, "cannot create locale"));
   }
   ~Locale() { freelocale(locale_); }
 
-  Type get() const { return 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 strtod(const char*& str) const {
+    char* end = nullptr;
     double result = strtod_l(str, &end, locale_);
     str = end;
     return result;
@@ -406,12 +308,4 @@ class Locale {
 #endif  // FMT_LOCALE
 FMT_END_NAMESPACE
 
-#if !FMT_USE_RVALUE_REFERENCES
-namespace std {
-// For compatibility with C++98.
-inline fmt::buffered_file &move(fmt::buffered_file &f) { return f; }
-inline fmt::file &move(fmt::file &f) { return f; }
-}
-#endif
-
 #endif  // FMT_POSIX_H_

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.
@@ -12,20 +12,19 @@
 #ifndef FMT_RANGES_H_
 #define FMT_RANGES_H_
 
-#include "format.h"
 #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();
   }
 };
@@ -33,7 +32,8 @@ struct formatting_base {
 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.
+      FMT_RANGE_OUTPUT_LENGTH_LIMIT;  // output only up to N items from the
+                                      // range.
   Char prefix;
   Char delimiter;
   Char postfix;
@@ -55,84 +55,78 @@ struct formatting_tuple : formatting_base<Char> {
 namespace internal {
 
 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... Ts>
-struct conditional_helper {};
+template <typename Char>
+struct is_like_std_string<fmt::basic_string_view<Char>> : std::true_type {};
 
-template <typename T, typename _ = void>
-struct is_range_ : std::false_type {};
+template <typename... Ts> struct conditional_helper {};
+
+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,
+                  (void)std::declval<typename std::tuple_element<0, U>::type>(),
+                  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 index_sequence = std::index_sequence<N...>;
 template <std::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 std::size_t size() { return sizeof...(N); }
 };
 
 template <std::size_t... N>
@@ -148,7 +142,7 @@ using make_index_sequence = make_integer_sequence<std::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)...};
@@ -156,26 +150,25 @@ 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 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 ? " \"{}\"" : "\"{}\"";
 }
 
@@ -183,61 +176,58 @@ 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 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;
+      internal::is_tuple_like_<T>::value && !internal::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 = internal::copy(formatting.delimiter, out);
       }
-      format_to(out,
-                internal::format_str_quoted(
-                    (formatting.add_delimiter_spaces && i > 0), v),
-                v);
+      out = format_to(out,
+                      internal::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;
+    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);
@@ -252,54 +242,124 @@ public:
   }
 };
 
-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;
+      internal::is_range_<T>::value &&
+      !internal::is_like_std_string<T>::value &&
+      !std::is_convertible<T, std::basic_string<Char>>::value &&
+      !std::is_constructible<internal::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> {
-
+                 enable_if_t<fmt::is_range<RangeT, Char>::value>> {
   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);
+  typename FormatContext::iterator format(const RangeT& values,
+                                          FormatContext& ctx) {
+    auto out = internal::copy(formatting.prefix, ctx.out());
     std::size_t i = 0;
     for (auto it = values.begin(), end = values.end(); it != end; ++it) {
       if (i > 0) {
-        if (formatting.add_prepostfix_space) {
-          *out++ = ' ';
-        }
-        internal::copy(formatting.delimiter, out);
+        if (formatting.add_prepostfix_space) *out++ = ' ';
+        out = internal::copy(formatting.delimiter, out);
       }
-      format_to(out,
-                internal::format_str_quoted(
-                    (formatting.add_delimiter_spaces && i > 0), *it),
-                *it);
+      out = format_to(out,
+                      internal::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 internal::copy(formatting.postfix, out);
   }
 };
 
+template <typename Char, typename... T> struct tuple_arg_join : internal::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, internal::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,
+      internal::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};
+}
+
 FMT_END_NAMESPACE
 
-#endif // FMT_RANGES_H_
-
+#endif  // FMT_RANGES_H_

include/fmt/safe-duration-cast.h

@@ -0,0 +1,293 @@
+/*
+ * For conversion between std::chrono::durations without undefined
+ * behaviour or erroneous results.
+ * This is a stripped down version of duration_cast, for inclusion in fmt.
+ * See https://github.com/pauldreik/safe_duration_cast
+ *
+ * Copyright Paul Dreik 2019
+ *
+ * This file is licensed under the fmt license, see format.h
+ */
+
+#include <chrono>
+#include <cmath>
+#include <limits>
+#include <type_traits>
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+
+namespace safe_duration_cast {
+
+template <typename To, typename From,
+          FMT_ENABLE_IF(!std::is_same<From, To>::value &&
+                        std::numeric_limits<From>::is_signed ==
+                            std::numeric_limits<To>::is_signed)>
+FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
+  ec = 0;
+  using F = std::numeric_limits<From>;
+  using T = std::numeric_limits<To>;
+  static_assert(F::is_integer, "From must be integral");
+  static_assert(T::is_integer, "To must be integral");
+
+  // A and B are both signed, or both unsigned.
+  if (F::digits <= T::digits) {
+    // From fits in To without any problem.
+  } else {
+    // From does not always fit in To, resort to a dynamic check.
+    if (from < T::min() || from > T::max()) {
+      // outside range.
+      ec = 1;
+      return {};
+    }
+  }
+  return static_cast<To>(from);
+}
+
+/**
+ * converts From to To, without loss. If the dynamic value of from
+ * can't be converted to To without loss, ec is set.
+ */
+template <typename To, typename From,
+          FMT_ENABLE_IF(!std::is_same<From, To>::value &&
+                        std::numeric_limits<From>::is_signed !=
+                            std::numeric_limits<To>::is_signed)>
+FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
+  ec = 0;
+  using F = std::numeric_limits<From>;
+  using T = std::numeric_limits<To>;
+  static_assert(F::is_integer, "From must be integral");
+  static_assert(T::is_integer, "To must be integral");
+
+  if (F::is_signed && !T::is_signed) {
+    // From may be negative, not allowed!
+    if (fmt::internal::is_negative(from)) {
+      ec = 1;
+      return {};
+    }
+
+    // From is positive. Can it always fit in To?
+    if (F::digits <= T::digits) {
+      // yes, From always fits in To.
+    } else {
+      // from may not fit in To, we have to do a dynamic check
+      if (from > static_cast<From>(T::max())) {
+        ec = 1;
+        return {};
+      }
+    }
+  }
+
+  if (!F::is_signed && T::is_signed) {
+    // can from be held in To?
+    if (F::digits < T::digits) {
+      // yes, From always fits in To.
+    } else {
+      // from may not fit in To, we have to do a dynamic check
+      if (from > static_cast<From>(T::max())) {
+        // outside range.
+        ec = 1;
+        return {};
+      }
+    }
+  }
+
+  // reaching here means all is ok for lossless conversion.
+  return static_cast<To>(from);
+
+}  // function
+
+template <typename To, typename From,
+          FMT_ENABLE_IF(std::is_same<From, To>::value)>
+FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
+  ec = 0;
+  return from;
+}  // function
+
+// clang-format off
+/**
+ * converts From to To if possible, otherwise ec is set.
+ *
+ * input                            |    output
+ * ---------------------------------|---------------
+ * NaN                              | NaN
+ * Inf                              | Inf
+ * normal, fits in output           | converted (possibly lossy)
+ * normal, does not fit in output   | ec is set
+ * subnormal                        | best effort
+ * -Inf                             | -Inf
+ */
+// clang-format on
+template <typename To, typename From,
+          FMT_ENABLE_IF(!std::is_same<From, To>::value)>
+FMT_CONSTEXPR To safe_float_conversion(const From from, int& ec) {
+  ec = 0;
+  using T = std::numeric_limits<To>;
+  static_assert(std::is_floating_point<From>::value, "From must be floating");
+  static_assert(std::is_floating_point<To>::value, "To must be floating");
+
+  // catch the only happy case
+  if (std::isfinite(from)) {
+    if (from >= T::lowest() && from <= T::max()) {
+      return static_cast<To>(from);
+    }
+    // not within range.
+    ec = 1;
+    return {};
+  }
+
+  // nan and inf will be preserved
+  return static_cast<To>(from);
+}  // function
+
+template <typename To, typename From,
+          FMT_ENABLE_IF(std::is_same<From, To>::value)>
+FMT_CONSTEXPR To safe_float_conversion(const From from, int& ec) {
+  ec = 0;
+  static_assert(std::is_floating_point<From>::value, "From must be floating");
+  return from;
+}
+
+/**
+ * safe duration cast between integral durations
+ */
+template <typename To, typename FromRep, typename FromPeriod,
+          FMT_ENABLE_IF(std::is_integral<FromRep>::value),
+          FMT_ENABLE_IF(std::is_integral<typename To::rep>::value)>
+To safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from,
+                      int& ec) {
+  using From = std::chrono::duration<FromRep, FromPeriod>;
+  ec = 0;
+  // the basic idea is that we need to convert from count() in the from type
+  // to count() in the To type, by multiplying it with this:
+  struct Factor
+      : std::ratio_divide<typename From::period, typename To::period> {};
+
+  static_assert(Factor::num > 0, "num must be positive");
+  static_assert(Factor::den > 0, "den must be positive");
+
+  // the conversion is like this: multiply from.count() with Factor::num
+  // /Factor::den and convert it to To::rep, all this without
+  // overflow/underflow. let's start by finding a suitable type that can hold
+  // both To, From and Factor::num
+  using IntermediateRep =
+      typename std::common_type<typename From::rep, typename To::rep,
+                                decltype(Factor::num)>::type;
+
+  // safe conversion to IntermediateRep
+  IntermediateRep count =
+      lossless_integral_conversion<IntermediateRep>(from.count(), ec);
+  if (ec) {
+    return {};
+  }
+  // multiply with Factor::num without overflow or underflow
+  if (Factor::num != 1) {
+    const auto max1 = internal::max_value<IntermediateRep>() / Factor::num;
+    if (count > max1) {
+      ec = 1;
+      return {};
+    }
+    const auto min1 = std::numeric_limits<IntermediateRep>::min() / Factor::num;
+    if (count < min1) {
+      ec = 1;
+      return {};
+    }
+    count *= Factor::num;
+  }
+
+  // this can't go wrong, right? den>0 is checked earlier.
+  if (Factor::den != 1) {
+    count /= Factor::den;
+  }
+  // convert to the to type, safely
+  using ToRep = typename To::rep;
+  const ToRep tocount = lossless_integral_conversion<ToRep>(count, ec);
+  if (ec) {
+    return {};
+  }
+  return To{tocount};
+}
+
+/**
+ * safe duration_cast between floating point durations
+ */
+template <typename To, typename FromRep, typename FromPeriod,
+          FMT_ENABLE_IF(std::is_floating_point<FromRep>::value),
+          FMT_ENABLE_IF(std::is_floating_point<typename To::rep>::value)>
+To safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from,
+                      int& ec) {
+  using From = std::chrono::duration<FromRep, FromPeriod>;
+  ec = 0;
+  if (std::isnan(from.count())) {
+    // nan in, gives nan out. easy.
+    return To{std::numeric_limits<typename To::rep>::quiet_NaN()};
+  }
+  // maybe we should also check if from is denormal, and decide what to do about
+  // it.
+
+  // +-inf should be preserved.
+  if (std::isinf(from.count())) {
+    return To{from.count()};
+  }
+
+  // the basic idea is that we need to convert from count() in the from type
+  // to count() in the To type, by multiplying it with this:
+  struct Factor
+      : std::ratio_divide<typename From::period, typename To::period> {};
+
+  static_assert(Factor::num > 0, "num must be positive");
+  static_assert(Factor::den > 0, "den must be positive");
+
+  // the conversion is like this: multiply from.count() with Factor::num
+  // /Factor::den and convert it to To::rep, all this without
+  // overflow/underflow. let's start by finding a suitable type that can hold
+  // both To, From and Factor::num
+  using IntermediateRep =
+      typename std::common_type<typename From::rep, typename To::rep,
+                                decltype(Factor::num)>::type;
+
+  // force conversion of From::rep -> IntermediateRep to be safe,
+  // even if it will never happen be narrowing in this context.
+  IntermediateRep count =
+      safe_float_conversion<IntermediateRep>(from.count(), ec);
+  if (ec) {
+    return {};
+  }
+
+  // multiply with Factor::num without overflow or underflow
+  if (Factor::num != 1) {
+    constexpr auto max1 = internal::max_value<IntermediateRep>() /
+                          static_cast<IntermediateRep>(Factor::num);
+    if (count > max1) {
+      ec = 1;
+      return {};
+    }
+    constexpr auto min1 = std::numeric_limits<IntermediateRep>::lowest() /
+                          static_cast<IntermediateRep>(Factor::num);
+    if (count < min1) {
+      ec = 1;
+      return {};
+    }
+    count *= static_cast<IntermediateRep>(Factor::num);
+  }
+
+  // this can't go wrong, right? den>0 is checked earlier.
+  if (Factor::den != 1) {
+    using common_t = typename std::common_type<IntermediateRep, intmax_t>::type;
+    count /= static_cast<common_t>(Factor::den);
+  }
+
+  // convert to the to type, safely
+  using ToRep = typename To::rep;
+
+  const ToRep tocount = safe_float_conversion<ToRep>(count, ec);
+  if (ec) {
+    return {};
+  }
+  return To{tocount};
+}
+
+}  // namespace safe_duration_cast
+
+FMT_END_NAMESPACE

include/fmt/time.h

@@ -1,152 +0,0 @@
-// Formatting library for C++ - time formatting
-//
-// Copyright (c) 2012 - 2016, 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>
-
-FMT_BEGIN_NAMESPACE
-
-namespace internal{
-inline null<> localtime_r(...) { return null<>(); }
-inline null<> localtime_s(...) { return null<>(); }
-inline null<> gmtime_r(...) { return null<>(); }
-inline null<> gmtime_s(...) { return null<>(); }
-}
-
-// 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; }
-
-    bool fallback(internal::null<>) {
-      using namespace fmt::internal;
-      std::tm *tm = std::localtime(&time_);
-      if (tm) tm_ = *tm;
-      return tm != FMT_NULL;
-    }
-  };
-  dispatcher lt(time);
-  if (lt.run())
-    return lt.tm_;
-  // Too big time values may be unsupported.
-  FMT_THROW(format_error("time_t value out of range"));
-}
-
-// 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; }
-
-    bool fallback(internal::null<>) {
-      std::tm *tm = std::gmtime(&time_);
-      if (tm) tm_ = *tm;
-      return tm != FMT_NULL;
-    }
-  };
-  dispatcher gt(time);
-  if (gt.run())
-    return gt.tm_;
-  // Too big time values may be unsupported.
-  FMT_THROW(format_error("time_t value out of range"));
-}
-
-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 = internal::null_terminating_iterator<Char>(ctx);
-    if (*it == ':')
-      ++it;
-    auto end = it;
-    while (*end && *end != '}')
-      ++end;
-    tm_format.reserve(end - it + 1);
-    using internal::pointer_from;
-    tm_format.append(pointer_from(it), pointer_from(end));
-    tm_format.push_back('\0');
-    return pointer_from(end);
-  }
-
-  template <typename FormatContext>
-  auto format(const std::tm &tm, FormatContext &ctx) -> decltype(ctx.out()) {
-    internal::basic_buffer<Char> &buf = internal::get_container(ctx.out());
-    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 ctx.out();
-  }
-
-  basic_memory_buffer<Char> tm_format;
-};
-FMT_END_NAMESPACE
-
-#endif  // FMT_TIME_H_

src/format.cc

@@ -8,45 +8,50 @@
 #include "fmt/format-inl.h"
 
 FMT_BEGIN_NAMESPACE
-namespace internal {
-// Force linking of inline functions into the library.
-std::string (*vformat_ref)(string_view, format_args) = vformat;
-std::wstring (*vformat_wref)(wstring_view, wformat_args) = vformat;
-}
+template struct FMT_API internal::basic_data<void>;
 
-template struct internal::basic_data<void>;
+// Workaround a bug in MSVC2013 that prevents instantiation of grisu_format.
+bool (*instantiate_grisu_format)(double, internal::buffer<char>&, int, unsigned,
+                                 int&) = internal::grisu_format;
+
+#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
+template FMT_API internal::locale_ref::locale_ref(const std::locale& loc);
+template FMT_API std::locale internal::locale_ref::get<std::locale>() const;
+#endif
 
 // Explicit instantiations for char.
 
-template FMT_API char internal::thousands_sep(locale_provider *lp);
+template FMT_API char internal::thousands_sep_impl(locale_ref);
+template FMT_API char internal::decimal_point_impl(locale_ref);
 
-template void basic_fixed_buffer<char>::grow(std::size_t);
+template FMT_API void internal::buffer<char>::append(const char*, const char*);
 
-template void internal::arg_map<format_context>::init(
-    const basic_format_args<format_context> &args);
+template FMT_API void internal::arg_map<format_context>::init(
+    const basic_format_args<format_context>& args);
 
-template FMT_API int internal::char_traits<char>::format_float(
-    char *buffer, std::size_t size, const char *format, int precision,
-    double value);
+template FMT_API std::string internal::vformat<char>(
+    string_view, basic_format_args<format_context>);
 
-template FMT_API int internal::char_traits<char>::format_float(
-    char *buffer, std::size_t size, const char *format, int precision,
-    long double value);
+template FMT_API format_context::iterator internal::vformat_to(
+    internal::buffer<char>&, string_view, basic_format_args<format_context>);
+
+template FMT_API char* internal::sprintf_format(double, internal::buffer<char>&,
+                                                sprintf_specs);
+template FMT_API char* internal::sprintf_format(long double,
+                                                internal::buffer<char>&,
+                                                sprintf_specs);
 
 // Explicit instantiations for wchar_t.
 
-template FMT_API wchar_t internal::thousands_sep(locale_provider *lp);
+template FMT_API wchar_t internal::thousands_sep_impl(locale_ref);
+template FMT_API wchar_t internal::decimal_point_impl(locale_ref);
 
-template void basic_fixed_buffer<wchar_t>::grow(std::size_t);
+template FMT_API void internal::buffer<wchar_t>::append(const wchar_t*,
+                                                        const wchar_t*);
 
-template void internal::arg_map<wformat_context>::init(
-    const basic_format_args<wformat_context> &args);
+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 *buffer, std::size_t size, const wchar_t *format,
-    int precision, double value);
-
-template FMT_API int internal::char_traits<wchar_t>::format_float(
-    wchar_t *buffer, std::size_t size, const wchar_t *format,
-    int precision, long double value);
+template FMT_API std::wstring internal::vformat<wchar_t>(
+    wstring_view, basic_format_args<wformat_context>);
 FMT_END_NAMESPACE

src/posix.cc

@@ -7,49 +7,49 @@
 
 // Disable bogus MSVC warnings.
 #if !defined(_CRT_SECURE_NO_WARNINGS) && defined(_MSC_VER)
-# define _CRT_SECURE_NO_WARNINGS
+#  define _CRT_SECURE_NO_WARNINGS
 #endif
 
 #include "fmt/posix.h"
 
-#include <limits.h>
-#include <sys/types.h>
+#include <climits>
 #include <sys/stat.h>
+#include <sys/types.h>
 
 #ifndef _WIN32
-# include <unistd.h>
+#  include <unistd.h>
 #else
-# ifndef WIN32_LEAN_AND_MEAN
-#  define WIN32_LEAN_AND_MEAN
-# endif
-# include <windows.h>
-# include <io.h>
+#  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
+#  define O_CREAT _O_CREAT
+#  define O_TRUNC _O_TRUNC
 
-# ifndef S_IRUSR
-#  define S_IRUSR _S_IREAD
-# endif
+#  ifndef S_IRUSR
+#    define S_IRUSR _S_IREAD
+#  endif
 
-# ifndef S_IWUSR
-#  define S_IWUSR _S_IWRITE
-# endif
+#  ifndef S_IWUSR
+#    define S_IWUSR _S_IWRITE
+#  endif
 
-# ifdef __MINGW32__
-#  define _SH_DENYNO 0x40
-# endif
+#  ifdef __MINGW32__
+#    define _SH_DENYNO 0x40
+#  endif
 
 #endif  // _WIN32
 
 #ifdef fileno
-# undef fileno
+#  undef fileno
 #endif
 
 namespace {
 #ifdef _WIN32
 // Return type of read and write functions.
-typedef int RWResult;
+using RWResult = int;
 
 // On Windows the count argument to read and write is unsigned, so convert
 // it from size_t preventing integer overflow.
@@ -58,11 +58,11 @@ inline unsigned convert_rwcount(std::size_t count) {
 }
 #else
 // Return type of read and write functions.
-typedef ssize_t RWResult;
+using RWResult = ssize_t;
 
 inline std::size_t convert_rwcount(std::size_t count) { return count; }
 #endif
-}
+}  // namespace
 
 FMT_BEGIN_NAMESPACE
 
@@ -72,19 +72,17 @@ buffered_file::~buffered_file() FMT_NOEXCEPT {
 }
 
 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);
+  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;
+  if (!file_) return;
   int result = FMT_SYSTEM(fclose(file_));
-  file_ = FMT_NULL;
-  if (result != 0)
-    FMT_THROW(system_error(errno, "cannot close 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.
@@ -92,8 +90,7 @@ void buffered_file::close() {
 
 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"));
+  if (fd == -1) FMT_THROW(system_error(errno, "cannot get file descriptor"));
   return fd;
 }
 
@@ -117,14 +114,12 @@ file::~file() FMT_NOEXCEPT {
 }
 
 void file::close() {
-  if (fd_ == -1)
-    return;
+  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"));
+  if (result != 0) FMT_THROW(system_error(errno, "cannot close file"));
 }
 
 long long file::size() const {
@@ -143,29 +138,27 @@ long long file::size() const {
   unsigned long long long_size = size_upper;
   return (long_size << sizeof(DWORD) * CHAR_BIT) | size_lower;
 #else
-  typedef struct stat Stat;
+  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 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) {
+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"));
+  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) {
+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"));
+  if (result < 0) FMT_THROW(system_error(errno, "cannot write to file"));
   return internal::to_unsigned(result);
 }
 
@@ -182,19 +175,18 @@ 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));
+    FMT_THROW(system_error(errno, "cannot duplicate file descriptor {} to {}",
+                           fd_, fd));
   }
 }
 
-void file::dup2(int fd, error_code &ec) FMT_NOEXCEPT {
+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);
+  if (result == -1) ec = error_code(errno);
 }
 
-void file::pipe(file &read_end, file &write_end) {
+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();
@@ -209,20 +201,19 @@ void file::pipe(file &read_end, file &write_end) {
   // 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"));
+  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) {
+buffered_file file::fdopen(const char* mode) {
   // Don't retry as fdopen doesn't return EINTR.
-  FILE *f = FMT_POSIX_CALL(fdopen(fd_, mode));
+  FILE* f = FMT_POSIX_CALL(fdopen(fd_, mode));
   if (!f)
-    FMT_THROW(system_error(errno,
-                           "cannot associate stream with file descriptor"));
+    FMT_THROW(
+        system_error(errno, "cannot associate stream with file descriptor"));
   buffered_file bf(f);
   fd_ = -1;
   return bf;
@@ -235,10 +226,8 @@ long getpagesize() {
   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"));
+  if (size < 0) FMT_THROW(system_error(errno, "cannot get memory page size"));
   return size;
 #endif
 }
 FMT_END_NAMESPACE
-

src/text/boost/assert.hpp

@@ -0,0 +1,4 @@
+#ifndef BOOST_ASSERT
+#include <assert.h>
+# define BOOST_ASSERT(condition) assert(condition)
+#endif

src/text/boost/container/small_vector.hpp

@@ -0,0 +1,13 @@
+#ifndef TEXT_BOOST_CONTAINER_SMALL_VECTOR_HPP
+#define TEXT_BOOST_CONTAINER_SMALL_VECTOR_HPP
+
+#include <vector>
+
+namespace boost {
+namespace container {
+template <typename T, size_t>
+using small_vector = std::vector<T>;
+}
+}
+
+#endif  // TEXT_BOOST_CONTAINER_SMALL_VECTOR_HPP

src/text/boost/text/config.hpp

@@ -0,0 +1,102 @@
+#ifndef BOOST_TEXT_CONFIG_HPP
+#define BOOST_TEXT_CONFIG_HPP
+
+
+/** There are ICU-based implementations of many operations, but those are only
+    defined when BOOST_TEXT_HAS_ICU is nonzero.  If you define this, you must
+    make sure the the ICU headers are in your path, and that your build
+    properly links in ICU. */
+#ifndef BOOST_TEXT_HAS_ICU
+#    define BOOST_TEXT_HAS_ICU 0
+#endif
+
+/** There are ICU-based implementations of many operations, but those are only
+    used when BOOST_TEXT_HAS_ICU and BOOST_TEXT_USE_ICU are both nonzero. */
+#ifndef BOOST_TEXT_USE_ICU
+#    define BOOST_TEXT_USE_ICU 0
+#endif
+
+/** When you insert into a rope, the incoming sequence may be inserted as a
+    new segment, or if it falls within an existing string-segment, it may be
+    inserted into the string object used to represent that segment.  This only
+    happens if the incoming sequence will fit within the existing segment's
+    capacity, or if the segment is smaller than a certain limit.
+    BOOST_TEXT_STRING_INSERT_MAX is that limit. */
+#ifndef BOOST_TEXT_STRING_INSERT_MAX
+#    define BOOST_TEXT_STRING_INSERT_MAX 4096
+#endif
+
+#ifndef BOOST_TEXT_DOXYGEN
+
+// Nothing before GCC 6 has proper C++14 constexpr support.
+#if defined(__GNUC__) && __GNUC__ < 6 && !defined(__clang__)
+#    define BOOST_TEXT_CXX14_CONSTEXPR
+#    define BOOST_TEXT_NO_CXX14_CONSTEXPR
+#elif defined(_MSC_VER) && _MSC_VER <= 1915
+#    define BOOST_TEXT_CXX14_CONSTEXPR
+#    define BOOST_TEXT_NO_CXX14_CONSTEXPR
+#else
+#    define BOOST_TEXT_CXX14_CONSTEXPR
+#    if defined(BOOST_NO_CXX14_CONSTEXPR)
+#        define BOOST_TEXT_NO_CXX14_CONSTEXPR
+#    endif
+#endif
+
+// Implements separate compilation features as described in
+// http://www.boost.org/more/separate_compilation.html
+
+//  normalize macros
+
+#if !defined(BOOST_TEXT_DYN_LINK) && !defined(BOOST_TEXT_STATIC_LINK) &&       \
+    !defined(BOOST_ALL_DYN_LINK) && !defined(BOOST_ALL_STATIC_LINK)
+#    define BOOST_TEXT_STATIC_LINK
+#endif
+
+#if defined(BOOST_ALL_DYN_LINK) && !defined(BOOST_TEXT_DYN_LINK)
+#    define BOOST_TEXT_DYN_LINK
+#elif defined(BOOST_ALL_STATIC_LINK) && !defined(BOOST_TEXT_STATIC_LINK)
+#    define BOOST_TEXT_STATIC_LINK
+#endif
+
+#if defined(BOOST_TEXT_DYN_LINK) && defined(BOOST_TEXT_STATIC_LINK)
+#    error Must not define both BOOST_TEXT_DYN_LINK and BOOST_TEXT_STATIC_LINK
+#endif
+
+//  enable dynamic or static linking as requested
+
+#if defined(BOOST_ALL_DYN_LINK) || defined(BOOST_TEXT_DYN_LINK)
+#    if defined(BOOST_TEXT_SOURCE)
+#        define BOOST_TEXT_DECL BOOST_SYMBOL_EXPORT
+#    else
+#        define BOOST_TEXT_DECL BOOST_SYMBOL_IMPORT
+#    endif
+#else
+#    define BOOST_TEXT_DECL
+#endif
+
+#if 0 // TODO: Disabled for now.
+//  enable automatic library variant selection
+
+#if !defined(BOOST_TEXT_SOURCE) && !defined(BOOST_ALL_NO_LIB) &&               \
+    !defined(BOOST_TEXT_NO_LIB)
+//
+// Set the name of our library, this will get undef'ed by auto_link.hpp
+// once it's done with it:
+//
+#define BOOST_LIB_NAME boost_text
+//
+// If we're importing code from a dll, then tell auto_link.hpp about it:
+//
+#if defined(BOOST_ALL_DYN_LINK) || defined(BOOST_TEXT_DYN_LINK)
+#    define BOOST_DYN_LINK
+#endif
+//
+// And include the header that does the work:
+//
+#include <boost/config/auto_link.hpp>
+#endif  // auto-linking disabled
+#endif
+
+#endif // doxygen
+
+#endif

src/text/boost/text/detail/break_prop_iter.hpp

@@ -0,0 +1,51 @@
+#ifndef BOOST_TEXT_DETAIL_BREAK_PROP_ITER_HPP
+#define BOOST_TEXT_DETAIL_BREAK_PROP_ITER_HPP
+
+#include <boost/text/detail/lzw.hpp>
+
+#include <unordered_map>
+
+
+namespace boost { namespace text { namespace detail {
+
+    template<typename Enum>
+    struct lzw_to_break_prop_iter
+    {
+        using value_type = std::pair<uint32_t, Enum>;
+        using difference_type = int;
+        using pointer = unsigned char *;
+        using reference = unsigned char &;
+        using iterator_category = std::output_iterator_tag;
+        using buffer_t = container::small_vector<unsigned char, 256>;
+
+        lzw_to_break_prop_iter(
+            std::unordered_map<uint32_t, Enum> & map, buffer_t & buf) :
+            map_(&map),
+            buf_(&buf)
+        {}
+
+        lzw_to_break_prop_iter & operator=(unsigned char c)
+        {
+            buf_->push_back(c);
+            auto const element_bytes = 4;
+            auto it = buf_->begin();
+            for (auto end = buf_->end() - buf_->size() % element_bytes;
+                 it != end;
+                 it += element_bytes) {
+                (*map_)[bytes_to_cp(&*it)] = Enum(*(it + 3));
+            }
+            buf_->erase(buf_->begin(), it);
+            return *this;
+        }
+        lzw_to_break_prop_iter & operator*() { return *this; }
+        lzw_to_break_prop_iter & operator++() { return *this; }
+        lzw_to_break_prop_iter & operator++(int) { return *this; }
+
+    private:
+        std::unordered_map<uint32_t, Enum> * map_;
+        buffer_t * buf_;
+    };
+
+}}}
+
+#endif

src/text/boost/text/detail/lzw.hpp

@@ -0,0 +1,104 @@
+#ifndef BOOST_TEXT_DETAIL_LZW_HPP
+#define BOOST_TEXT_DETAIL_LZW_HPP
+
+#include <boost/assert.hpp>
+#include <boost/container/small_vector.hpp>
+
+#include <vector>
+
+
+namespace boost { namespace text { namespace detail {
+
+    inline uint32_t bytes_to_uint32_t(unsigned char const * chars)
+    {
+        return chars[0] << 24 | chars[1] << 16 | chars[2] << 8 | chars[3] << 0;
+    }
+
+    inline uint32_t bytes_to_cp(unsigned char const * chars)
+    {
+        return chars[0] << 16 | chars[1] << 8 | chars[2] << 0;
+    }
+
+    inline uint32_t bytes_to_uint16_t(unsigned char const * chars)
+    {
+        return chars[0] << 8 | chars[1] << 0;
+    }
+
+    enum : uint16_t { no_predecessor = 0xffff, no_value = 0xffff };
+
+    struct lzw_reverse_table_element
+    {
+        lzw_reverse_table_element(
+            uint16_t pred = no_predecessor, uint16_t value = no_value) :
+            pred_(pred),
+            value_(value)
+        {}
+        uint16_t pred_;
+        uint16_t value_;
+    };
+
+    using lzw_reverse_table = std::vector<lzw_reverse_table_element>;
+
+    template<typename OutIter>
+    OutIter
+    copy_table_entry(lzw_reverse_table const & table, uint16_t i, OutIter out)
+    {
+        *out++ = table[i].value_;
+        while (table[i].pred_ != no_predecessor) {
+            i = table[i].pred_;
+            *out++ = table[i].value_;
+        }
+        return out;
+    }
+
+    // Hardcoded to 16 bits.  Takes unsigned 16-bit LZW-compressed values as
+    // input and writes the decompressed unsigned char values to out.
+    template<typename Iter, typename OutIter>
+    OutIter lzw_decompress(Iter first, Iter last, OutIter out)
+    {
+        lzw_reverse_table reverse_table(1 << 16);
+        for (uint16_t i = 0; i < 256u; ++i) {
+            reverse_table[i].value_ = i;
+        }
+
+        container::small_vector<unsigned char, 256> table_entry;
+
+        uint32_t next_table_value = 256;
+        uint32_t const end_table_value = 1 << 16;
+
+        uint16_t prev_code = *first++;
+        BOOST_ASSERT(prev_code < 256);
+        unsigned char c = (unsigned char)prev_code;
+        table_entry.push_back(c);
+        *out++ = table_entry;
+
+        while (first != last) {
+            uint16_t const code = *first++;
+
+            table_entry.clear();
+            if (reverse_table[code].value_ == no_value) {
+                table_entry.push_back(c);
+                copy_table_entry(
+                    reverse_table, prev_code, std::back_inserter(table_entry));
+            } else {
+                copy_table_entry(
+                    reverse_table, code, std::back_inserter(table_entry));
+            }
+
+            *out++ = table_entry;
+            c = table_entry.back();
+
+            if (next_table_value < end_table_value) {
+                reverse_table[next_table_value++] =
+                    lzw_reverse_table_element{prev_code, c};
+            }
+
+            prev_code = code;
+        }
+
+        return out;
+    }
+
+}}}
+
+#endif

src/text/boost/text/grapheme_break.hpp

@@ -0,0 +1,224 @@
+#ifndef BOOST_TEXT_GRAPHEME_BREAK_HPP
+#define BOOST_TEXT_GRAPHEME_BREAK_HPP
+
+#include <array>
+#include <unordered_map>
+
+#include <stdint.h>
+
+#define BOOST_TEXT_DECL
+
+namespace boost { namespace text {
+
+    /** Analogue of `std::find()` that finds the last value `v` in `[first,
+        last)` for which `p(v)` is true. */
+    template<typename BidiIter, typename Pred>
+    BidiIter find_if_backward(BidiIter first, BidiIter last, Pred p)
+    {
+        auto it = last;
+        while (it != first) {
+            if (p(*--it))
+                return it;
+        }
+        return last;
+    }
+
+    /** The grapheme properties defined by Unicode. */
+    enum class grapheme_property {
+        Other,
+        CR,
+        LF,
+        Control,
+        Extend,
+        Regional_Indicator,
+        Prepend,
+        SpacingMark,
+        L,
+        V,
+        T,
+        LV,
+        LVT,
+        ExtPict,
+        ZWJ
+    };
+
+    namespace detail {
+        struct grapheme_prop_interval
+        {
+            uint32_t lo_;
+            uint32_t hi_;
+            grapheme_property prop_;
+        };
+
+        inline bool operator<(
+            grapheme_prop_interval lhs, grapheme_prop_interval rhs) noexcept
+        {
+            return lhs.hi_ <= rhs.lo_;
+        }
+
+        BOOST_TEXT_DECL std::array<grapheme_prop_interval, 6> const &
+        make_grapheme_prop_intervals();
+        BOOST_TEXT_DECL std::unordered_map<uint32_t, grapheme_property>
+        make_grapheme_prop_map();
+    }
+
+    /** Returns the grapheme property associated with code point `cp`. */
+    inline grapheme_property grapheme_prop(uint32_t cp) noexcept
+    {
+        static auto const map = detail::make_grapheme_prop_map();
+        static auto const intervals = detail::make_grapheme_prop_intervals();
+
+        auto const it = map.find(cp);
+        if (it == map.end()) {
+            auto const it2 = std::lower_bound(
+                intervals.begin(),
+                intervals.end(),
+                detail::grapheme_prop_interval{cp, cp + 1});
+            if (it2 == intervals.end() || cp < it2->lo_ || it2->hi_ <= cp)
+                return grapheme_property::Other;
+            return it2->prop_;
+        }
+        return it->second;
+    }
+
+    namespace detail {
+        inline bool skippable(grapheme_property prop) noexcept
+        {
+            return prop == grapheme_property::Extend;
+        }
+
+        enum class grapheme_break_emoji_state_t {
+            none,
+            first_emoji, // Indicates that prop points to an odd-count
+                         // emoji.
+            second_emoji // Indicates that prop points to an even-count
+                         // emoji.
+        };
+
+        template<typename CPIter>
+        struct grapheme_break_state
+        {
+            CPIter it;
+
+            grapheme_property prev_prop;
+            grapheme_property prop;
+
+            grapheme_break_emoji_state_t emoji_state;
+        };
+
+        template<typename CPIter>
+        grapheme_break_state<CPIter> next(grapheme_break_state<CPIter> state)
+        {
+            ++state.it;
+            state.prev_prop = state.prop;
+            return state;
+        }
+
+        template<typename CPIter>
+        grapheme_break_state<CPIter> prev(grapheme_break_state<CPIter> state)
+        {
+            --state.it;
+            state.prop = state.prev_prop;
+            return state;
+        }
+
+        template<typename CPIter>
+        bool gb11_prefix(CPIter first, CPIter prev_it)
+        {
+            auto final_prop = grapheme_property::Other;
+            find_if_backward(first, prev_it, [&final_prop](uint32_t cp) {
+                final_prop = grapheme_prop(cp);
+                return final_prop != grapheme_property::Extend;
+            });
+            return final_prop == grapheme_property::ExtPict;
+        }
+
+        inline bool table_grapheme_break(
+            grapheme_property lhs, grapheme_property rhs) noexcept
+        {
+            // Note that RI.RI was changed to '1' since that case is handled
+            // in the grapheme break FSM.
+
+            // clang-format off
+// See chart at https://unicode.org/Public/11.0.0/ucd/auxiliary/GraphemeBreakTest.html .
+constexpr std::array<std::array<bool, 15>, 15> grapheme_breaks = {{
+//   Other CR LF Ctrl Ext RI Pre SpcMk L  V  T  LV LVT ExtPict ZWJ
+    {{1,   1, 1, 1,   0,  1, 1,  0,    1, 1, 1, 1, 1,  1,      0}}, // Other
+    {{1,   1, 0, 1,   1,  1, 1,  1,    1, 1, 1, 1, 1,  1,      1}}, // CR
+    {{1,   1, 1, 1,   1,  1, 1,  1,    1, 1, 1, 1, 1,  1,      1}}, // LF
+    {{1,   1, 1, 1,   1,  1, 1,  1,    1, 1, 1, 1, 1,  1,      1}}, // Control
+    {{1,   1, 1, 1,   0,  1, 1,  0,    1, 1, 1, 1, 1,  1,      0}}, // Extend
+    {{1,   1, 1, 1,   0,  1, 1,  0,    1, 1, 1, 1, 1,  1,      0}}, // RI
+    {{0,   1, 1, 1,   0,  0, 0,  0,    0, 0, 0, 0, 0,  0,      0}}, // Prepend
+    {{1,   1, 1, 1,   0,  1, 1,  0,    1, 1, 1, 1, 1,  1,      0}}, // SpacingMark
+    {{1,   1, 1, 1,   0,  1, 1,  0,    0, 0, 1, 0, 0,  1,      0}}, // L
+    {{1,   1, 1, 1,   0,  1, 1,  0,    1, 0, 0, 1, 1,  1,      0}}, // V
+    {{1,   1, 1, 1,   0,  1, 1,  0,    1, 1, 0, 1, 1,  1,      0}}, // T
+    {{1,   1, 1, 1,   0,  1, 1,  0,    1, 0, 0, 1, 1,  1,      0}}, // LV
+    {{1,   1, 1, 1,   0,  1, 1,  0,    1, 1, 0, 1, 1,  1,      0}}, // LVT
+    {{1,   1, 1, 1,   0,  1, 1,  0,    1, 1, 1, 1, 1,  1,      0}}, // ExtPict
+    {{1,   1, 1, 1,   0,  1, 1,  0,    1, 1, 1, 1, 1,  1,      0}}, // ZWJ
+
+}};
+            // clang-format on
+            auto const lhs_int = static_cast<int>(lhs);
+            auto const rhs_int = static_cast<int>(rhs);
+            return grapheme_breaks[lhs_int][rhs_int];
+        }
+    }
+
+    template<typename CPIter, typename Sentinel>
+    CPIter next_grapheme_break(CPIter first, Sentinel last) noexcept
+    {
+        if (first == last)
+            return first;
+
+        detail::grapheme_break_state<CPIter> state;
+        state.it = first;
+
+        if (++state.it == last)
+            return state.it;
+
+        state.prev_prop = grapheme_prop(*std::prev(state.it));
+        state.prop = grapheme_prop(*state.it);
+
+        state.emoji_state =
+            state.prev_prop == grapheme_property::Regional_Indicator
+                ? detail::grapheme_break_emoji_state_t::first_emoji
+                : detail::grapheme_break_emoji_state_t::none;
+
+        for (; state.it != last; state = next(state)) {
+            state.prop = grapheme_prop(*state.it);
+
+            // GB11
+            if (state.prev_prop == grapheme_property::ZWJ &&
+                state.prop == grapheme_property::ExtPict &&
+                detail::gb11_prefix(first, std::prev(state.it))) {
+                continue;
+            }
+
+            if (state.emoji_state ==
+                detail::grapheme_break_emoji_state_t::first_emoji) {
+                if (state.prop == grapheme_property::Regional_Indicator) {
+                    state.emoji_state =
+                        detail::grapheme_break_emoji_state_t::none;
+                    continue;
+                } else {
+                    state.emoji_state =
+                        detail::grapheme_break_emoji_state_t::none;
+                }
+            } else if (state.prop == grapheme_property::Regional_Indicator) {
+                state.emoji_state =
+                    detail::grapheme_break_emoji_state_t::first_emoji;
+            }
+
+            if (detail::table_grapheme_break(state.prev_prop, state.prop))
+                return state.it;
+        }
+
+        return state.it;
+    }
+
+}}
+
+#endif

src/text/boost/throw_exception.hpp

@@ -0,0 +1,9 @@
+#ifndef TEXT_BOOST_THROW_EXCEPTION_HPP
+#define TEXT_BOOST_THROW_EXCEPTION_HPP
+
+namespace boost {
+template <typename E>
+void throw_exception(const E& e) { throw e; }
+}
+
+#endif  // TEXT_BOOST_THROW_EXCEPTION_HPP

support/AndroidManifest.xml

@@ -1 +1 @@
-<manifest package="fmt" />
+<manifest package="net.fmtlib" />

support/Vagrantfile

@@ -0,0 +1,19 @@
+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+# A vagrant config for testing against gcc-4.8.
+Vagrant.configure("2") do |config|
+  config.vm.box = "ubuntu/trusty64"
+
+  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

@@ -1,15 +1,27 @@
+
 // General gradle arguments for root project
 buildscript {    
     repositories {
         google()
         jcenter()
     }
-
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.0.1'
+        //
+        // https://developer.android.com/studio/releases/gradle-plugin
+        //
+        // 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
+        //
+        // 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 {
+    google()
+    jcenter()
+}
+    
 // Output: Shared library (.so) for Android 
 apply plugin: 'com.android.library'
 
@@ -24,20 +36,17 @@ android {
     splits {
         abi {
             enable true
-            // Be general, as much as possible ...
-            // universalApk true 
-
             // Specify platforms for Application
             reset()
-            include "x86", "x86_64", "armeabi-v7a", "arm64-v8a"
+            include  "arm64-v8a", "armeabi-v7a", "x86_64"
         }
     }
 
     defaultConfig {
         minSdkVersion 21    // Android 5.0+
         targetSdkVersion 25 // Follow Compile SDK
-        versionCode 16      // Follow release count
-        versionName "4.1.0" // Follow Official version
+        versionCode 21      // Follow release count
+        versionName "5.3.0" // Follow Official version
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         
         externalNativeBuild {
@@ -46,7 +55,7 @@ android {
                 arguments "-DBUILD_SHARED_LIBS=true"    // Build shared object
                 arguments "-DFMT_TEST=false"            // Skip test
                 arguments "-DFMT_DOC=false"             // Skip document
-                cppFlags  "-std=c++14"
+                cppFlags  "-std=c++17"
             }
         }
         println("Gradle CMake Plugin: ")

support/cmake/cxx14.cmake

@@ -50,6 +50,7 @@ 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
+# Can be removed once gcc 4.4 support is dropped.
 check_cxx_source_compiles("
   template <class T, class ...Types>
   struct S { typedef typename S<Types...>::type type; };
@@ -58,33 +59,6 @@ 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 +68,14 @@ 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

@@ -0,0 +1,11 @@
+prefix=@CMAKE_INSTALL_PREFIX@
+exec_prefix=@CMAKE_INSTALL_PREFIX@
+libdir=${exec_prefix}/@CMAKE_INSTALL_LIBDIR@
+includedir=${prefix}/@CMAKE_INSTALL_INCLUDEDIR@
+
+Name: fmt
+Description: A modern formatting library
+Version: @FMT_VERSION@
+Libs: -L${libdir} -lfmt
+Cflags: -I${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/compute-powers.py

@@ -39,7 +39,7 @@ for i, exp in enumerate(range(min_exponent, max_exponent + 1, step)):
 
 print('Significands:', end='')
 for i, fp in enumerate(powers):
-    if i % 4 == 0:
+    if i % 3 == 0:
         print(end='\n ')
     print(' {:0<#16x}'.format(fp.f, ), end=',')
 

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
@@ -142,6 +145,7 @@ def update_site(env):
                 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(', size_t', ', std::size_t')
         # Fix a broken link in index.rst.
         index = os.path.join(target_doc_dir, 'index.rst')
         with rewrite(index) as b:
@@ -247,7 +251,8 @@ def release(args):
     package = 'fmt-{}.zip'.format(version)
     r = requests.post(
         '{}/{}/assets?name={}'.format(uploads_url, id, package),
-        params=params, files={package: open('build/fmt/' + package, 'rb')})
+        headers={'Content-Type': 'application/zip'},
+        params=params, data=open('build/fmt/' + package, 'rb'))
     if r.status_code != 201:
         raise Exception('Failed to upload an asset ' + str(r))
 

support/rst2md.py

@@ -1,6 +1,7 @@
+#!/usr/bin/env python
 # reStructuredText (RST) to GitHub-flavored Markdown converter
 
-import re
+import re, sys
 from docutils import core, nodes, writers
 
 
@@ -35,6 +36,9 @@ class Translator(nodes.NodeVisitor):
         self.version = re.match(r'(\d+\.\d+\.\d+).*', node.children[0]).group(1)
         raise nodes.SkipChildren
 
+    def visit_title_reference(self, node):
+        raise Exception(node)
+
     def depart_title(self, node):
         pass
 
@@ -109,6 +113,30 @@ class Translator(nodes.NodeVisitor):
     def depart_image(self, node):
         pass
 
+    def write_row(self, row, widths):
+        for i, entry in enumerate(row):
+            text = entry[0][0] if len(entry) > 0 else ''
+            if i != 0:
+                self.write('|')
+            self.write('{:{}}'.format(text, widths[i]))
+        self.write('\n')
+
+    def visit_table(self, node):
+        table = node.children[0]
+        colspecs = table[:-2]
+        thead = table[-2]
+        tbody = table[-1]
+        widths = [int(cs['colwidth']) for cs in colspecs]
+        sep = '|'.join(['-' * w for w in widths]) + '\n'
+        self.write('\n\n')
+        self.write_row(thead[0], widths)
+        self.write(sep)
+        for row in tbody:
+            self.write_row(row, widths)
+        raise nodes.SkipChildren
+
+    def depart_table(self, node):
+        pass
 
 class MDWriter(writers.Writer):
     """GitHub-flavored markdown writer"""
@@ -125,3 +153,7 @@ class MDWriter(writers.Writer):
 def convert(rst_path):
     """Converts RST file to Markdown."""
     return core.publish_file(source_path=rst_path, writer=MDWriter())
+
+
+if __name__ == '__main__':
+    convert(sys.argv[1])

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.

test/CMakeLists.txt

@@ -17,13 +17,20 @@ else ()
   target_compile_definitions(gmock PUBLIC GTEST_HAS_PTHREAD=0)
 endif ()
 
-if (NOT SUPPORTS_VARIADIC_TEMPLATES OR NOT SUPPORTS_INITIALIZER_LIST)
+if (NOT SUPPORTS_VARIADIC_TEMPLATES)
   target_compile_definitions(gmock PUBLIC GTEST_LANG_CXX11=0)
 endif ()
 
-# 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.
@@ -33,7 +40,7 @@ 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
@@ -74,28 +81,39 @@ 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(grisu-test)
+target_compile_definitions(grisu-test PRIVATE FMT_USE_GRISU=1)
 add_fmt_test(gtest-extra-test)
-add_fmt_test(format-test)
-add_fmt_test(format-impl-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(util-test mock-allocator.h)
 add_fmt_test(custom-formatter-test)
 add_fmt_test(ranges-test)
+add_fmt_test(scan-test)
 
-if (HAVE_OPEN)
+if (HAVE_OPEN AND NOT MSVC_BUILD_STATIC)
   add_fmt_executable(posix-mock-test
     posix-mock-test.cc ../src/format.cc ${TEST_MAIN_SRC})
   target_include_directories(
@@ -106,6 +124,9 @@ if (HAVE_OPEN)
   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)
 endif ()
@@ -122,22 +143,37 @@ else ()
   target_compile_definitions(header-only-test PRIVATE FMT_HEADER_ONLY=1)
 endif ()
 
-# Test that the library can be compiled with exceptions disabled.
-check_cxx_compiler_flag(-fno-exceptions HAVE_FNO_EXCEPTIONS_FLAG)
-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)
+  # 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 ()
+
+  # 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)
+
   # Test that the library compiles without windows.h.
   if (CMAKE_SYSTEM_NAME STREQUAL "Windows")
     add_library(no-windows-h-test ../src/format.cc)
@@ -150,10 +186,10 @@ if (FMT_PEDANTIC)
     target_include_directories(no-windows-h-test SYSTEM PUBLIC gtest gmock)
   endif ()
 
-  add_test(compile-test ${CMAKE_CTEST_COMMAND}
+  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 ${CMAKE_MAKE_PROGRAM}
     --build-options
@@ -162,8 +198,11 @@ if (FMT_PEDANTIC)
     "-DCXX_STANDARD_FLAG=${CXX_STANDARD_FLAG}"
     "-DPEDANTIC_COMPILE_FLAGS=${PEDANTIC_COMPILE_FLAGS}"
     "-DSUPPORTS_USER_DEFINED_LITERALS=${SUPPORTS_USER_DEFINED_LITERALS}")
+endif ()
 
-  # test if the targets are findable from the build directory
+# These tests are disabled on Windows because they take too long.
+if (FMT_PEDANTIC AND NOT WIN32)
+  # Test if the targets are found from the build directory.
   add_test(find-package-test ${CMAKE_CTEST_COMMAND}
     -C ${CMAKE_BUILD_TYPE}
     --build-and-test
@@ -178,7 +217,7 @@ if (FMT_PEDANTIC)
     "-DPEDANTIC_COMPILE_FLAGS=${PEDANTIC_COMPILE_FLAGS}"
     "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}")
 
-  # test if the targets are findable when add_subdirectory is used
+  # Test if the targets are found when add_subdirectory is used.
   add_test(add-subdirectory-test ${CMAKE_CTEST_COMMAND}
     -C ${CMAKE_BUILD_TYPE}
     --build-and-test
@@ -192,3 +231,21 @@ if (FMT_PEDANTIC)
     "-DPEDANTIC_COMPILE_FLAGS=${PEDANTIC_COMPILE_FLAGS}"
     "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}")
 endif ()
+
+# Activate optional CUDA tests if CUDA is found. For version selection, see
+# https://docs.nvidia.com/cuda/cuda-c-programming-guide/index.html#cpp14-language-features
+if (${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 ()

test/assert-test.cc

@@ -9,14 +9,14 @@
 #include "gtest.h"
 
 #if GTEST_HAS_DEATH_TEST
-# define EXPECT_DEBUG_DEATH_IF_SUPPORTED(statement, regex) \
+#  define EXPECT_DEBUG_DEATH_IF_SUPPORTED(statement, regex) \
     EXPECT_DEBUG_DEATH(statement, regex)
 #else
-# define EXPECT_DEBUG_DEATH_IF_SUPPORTED(statement, regex) \
+#  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!");
+  EXPECT_DEBUG_DEATH_IF_SUPPORTED(FMT_ASSERT(false, "don't panic!"),
+                                  "don't panic!");
 }

test/chrono-test.cc

@@ -0,0 +1,344 @@
+// 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 "fmt/chrono.h"
+#include "gtest-extra.h"
+
+#include <iomanip>
+
+std::tm make_tm() {
+  auto time = std::tm();
+  time.tm_mday = 1;
+  return time;
+}
+
+std::tm make_hour(int h) {
+  auto time = make_tm();
+  time.tm_hour = h;
+  return time;
+}
+
+std::tm make_minute(int m) {
+  auto time = make_tm();
+  time.tm_min = m;
+  return time;
+}
+
+std::tm make_second(int s) {
+  auto time = make_tm();
+  time.tm_sec = 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::ostringstream os;
+  os.imbue(loc);
+  facet.put(os, os, ' ', &time, spec, spec + std::strlen(spec));
+  return os.str();
+}
+
+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)));
+}
+
+#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",
+            fmt::format("{}", std::chrono::duration<int, std::atto>(42)));
+  EXPECT_EQ("42fs",
+            fmt::format("{}", std::chrono::duration<int, std::femto>(42)));
+  EXPECT_EQ("42ps",
+            fmt::format("{}", std::chrono::duration<int, std::pico>(42)));
+  EXPECT_EQ("42ns", fmt::format("{}", std::chrono::nanoseconds(42)));
+  EXPECT_EQ("42µs", fmt::format("{}", std::chrono::microseconds(42)));
+  EXPECT_EQ("42ms", fmt::format("{}", std::chrono::milliseconds(42)));
+  EXPECT_EQ("42cs",
+            fmt::format("{}", std::chrono::duration<int, std::centi>(42)));
+  EXPECT_EQ("42ds",
+            fmt::format("{}", std::chrono::duration<int, std::deci>(42)));
+  EXPECT_EQ("42s", fmt::format("{}", std::chrono::seconds(42)));
+  EXPECT_EQ("42das",
+            fmt::format("{}", std::chrono::duration<int, std::deca>(42)));
+  EXPECT_EQ("42hs",
+            fmt::format("{}", std::chrono::duration<int, std::hecto>(42)));
+  EXPECT_EQ("42ks",
+            fmt::format("{}", std::chrono::duration<int, std::kilo>(42)));
+  EXPECT_EQ("42Ms",
+            fmt::format("{}", std::chrono::duration<int, std::mega>(42)));
+  EXPECT_EQ("42Gs",
+            fmt::format("{}", std::chrono::duration<int, std::giga>(42)));
+  EXPECT_EQ("42Ts",
+            fmt::format("{}", std::chrono::duration<int, std::tera>(42)));
+  EXPECT_EQ("42Ps",
+            fmt::format("{}", std::chrono::duration<int, std::peta>(42)));
+  EXPECT_EQ("42Es",
+            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)));
+}
+
+TEST(ChronoTest, Align) {
+  auto s = std::chrono::seconds(42);
+  EXPECT_EQ("42s  ", fmt::format("{:5}", s));
+  EXPECT_EQ("42s  ", fmt::format("{:{}}", s, 5));
+  EXPECT_EQ("  42s", fmt::format("{:>5}", s));
+  EXPECT_EQ("**42s**", fmt::format("{:*^7}", s));
+  EXPECT_EQ("03:25:45    ",
+            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("{:~^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) {
+  EXPECT_EQ("%", fmt::format("{:%%}", std::chrono::seconds(0)));
+  EXPECT_EQ("\n", fmt::format("{:%n}", std::chrono::seconds(0)));
+  EXPECT_EQ("\t", fmt::format("{:%t}", std::chrono::seconds(0)));
+  EXPECT_EQ("00", fmt::format("{:%S}", std::chrono::seconds(0)));
+  EXPECT_EQ("00", fmt::format("{:%S}", std::chrono::seconds(60)));
+  EXPECT_EQ("42", fmt::format("{:%S}", std::chrono::seconds(42)));
+  EXPECT_EQ("01.234", fmt::format("{:%S}", std::chrono::milliseconds(1234)));
+  EXPECT_EQ("00", fmt::format("{:%M}", std::chrono::minutes(0)));
+  EXPECT_EQ("00", fmt::format("{:%M}", std::chrono::minutes(60)));
+  EXPECT_EQ("42", fmt::format("{:%M}", std::chrono::minutes(42)));
+  EXPECT_EQ("01", fmt::format("{:%M}", std::chrono::seconds(61)));
+  EXPECT_EQ("00", fmt::format("{:%H}", std::chrono::hours(0)));
+  EXPECT_EQ("00", fmt::format("{:%H}", std::chrono::hours(24)));
+  EXPECT_EQ("14", fmt::format("{:%H}", std::chrono::hours(14)));
+  EXPECT_EQ("01", fmt::format("{:%H}", std::chrono::minutes(61)));
+  EXPECT_EQ("12", fmt::format("{:%I}", std::chrono::hours(0)));
+  EXPECT_EQ("12", fmt::format("{:%I}", std::chrono::hours(12)));
+  EXPECT_EQ("12", fmt::format("{:%I}", std::chrono::hours(24)));
+  EXPECT_EQ("04", fmt::format("{:%I}", std::chrono::hours(4)));
+  EXPECT_EQ("02", fmt::format("{:%I}", std::chrono::hours(14)));
+  EXPECT_EQ("03:25:45",
+            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) {
+  auto sec = std::chrono::seconds(0);
+  EXPECT_THROW_MSG(fmt::format("{:%a}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%A}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%c}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%x}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%Ex}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%X}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%EX}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%D}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%F}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%Ec}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%w}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%u}", sec), fmt::format_error, "no date");
+  EXPECT_THROW_MSG(fmt::format("{:%b}", sec), fmt::format_error, "no date");
+  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("{:%Eq}", sec), fmt::format_error,
+                   "invalid format");
+  EXPECT_THROW_MSG(fmt::format("{:%Oq}", sec), fmt::format_error,
+                   "invalid format");
+}
+
+TEST(ChronoTest, Locale) {
+  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&) {
+  }
+  if (!has_locale) {
+    fmt::print("{} locale is missing.\n", loc_name);
+    return;
+  }
+  EXPECT_TIME("%OH", make_hour(14), std::chrono::hours(14));
+  EXPECT_TIME("%OI", make_hour(14), std::chrono::hours(14));
+  EXPECT_TIME("%OM", make_minute(42), std::chrono::minutes(42));
+  EXPECT_TIME("%OS", make_second(42), std::chrono::seconds(42));
+  auto time = make_tm();
+  time.tm_hour = 3;
+  time.tm_min = 25;
+  time.tm_sec = 45;
+  auto sec = std::chrono::seconds(12345);
+  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 +1,83 @@
+// 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 "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::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/compile-test.cc

@@ -0,0 +1,143 @@
+// 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 <stdint.h>
+#include <cctype>
+#include <cfloat>
+#include <climits>
+#include <cmath>
+#include <cstring>
+#include <deque>
+#include <list>
+#include <memory>
+#include <string>
+
+// Check if 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 "mock-allocator.h"
+#include "util.h"
+
+#undef ERROR
+#undef min
+#undef max
+
+using testing::Return;
+using testing::StrictMock;
+
+// 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::internal::compiled_format_base<decltype(format)> provider;
+  typedef fmt::internal::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::compile<int>("test {}");
+  EXPECT_EQ("test 42", fmt::format(prepared, 42));
+  const auto wprepared = fmt::compile<int>(L"test {}");
+  EXPECT_EQ(L"test 42", fmt::format(wprepared, 42));
+}
+
+#if FMT_USE_CONSTEXPR
+TEST(CompileTest, PassCompileString) {
+  const auto prepared = fmt::compile<int>(FMT_STRING("test {}"));
+  EXPECT_EQ("test 42", fmt::format(prepared, 42));
+  const auto wprepared = fmt::compile<int>(FMT_STRING(L"test {}"));
+  EXPECT_EQ(L"test 42", fmt::format(wprepared, 42));
+}
+#endif
+
+TEST(CompileTest, FormatToArrayOfChars) {
+  char buffer[32] = {0};
+  const auto prepared = fmt::compile<int>("4{}");
+  fmt::format_to(fmt::internal::make_checked(buffer, 32), prepared, 2);
+  EXPECT_EQ(std::string("42"), buffer);
+  wchar_t wbuffer[32] = {0};
+  const auto wprepared = fmt::compile<int>(L"4{}");
+  fmt::format_to(fmt::internal::make_checked(wbuffer, 32), wprepared, 2);
+  EXPECT_EQ(std::wstring(L"42"), wbuffer);
+}
+
+TEST(CompileTest, FormatToIterator) {
+  std::string s(2, ' ');
+  const auto prepared = fmt::compile<int>("4{}");
+  fmt::format_to(s.begin(), prepared, 2);
+  EXPECT_EQ("42", s);
+  std::wstring ws(2, L' ');
+  const auto wprepared = fmt::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::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::compile<int>("{:10}");
+  EXPECT_EQ(fmt::formatted_size(f, 42), 10);
+}
+
+TEST(CompileTest, MultipleTypes) {
+  auto f = fmt::compile<int, int>("{} {}");
+  EXPECT_EQ(fmt::format(f, 42, 42), "42 42");
+}
+
+struct formattable {};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<formattable> : formatter<const char*> {
+  auto format(formattable, format_context& ctx) -> decltype(ctx.out()) {
+    return formatter<const char*>::format("foo", ctx);
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(CompileTest, FormatUserDefinedType) {
+  auto f = fmt::compile<formattable>("{}");
+  EXPECT_EQ(fmt::format(f, formattable()), "foo");
+}
+
+TEST(CompileTest, EmptyFormatString) {
+  auto f = fmt::compile<>("");
+  EXPECT_EQ(fmt::format(f), "");
+}

test/core-test.cc

@@ -0,0 +1,637 @@
+// Formatting library for C++ - core tests
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include <algorithm>
+#include <climits>
+#include <cstring>
+#include <functional>
+#include <iterator>
+#include <limits>
+#include <memory>
+#include <string>
+#include <type_traits>
+
+#include "test-assert.h"
+
+#include "gmock.h"
+
+// Check if fmt/core.h compiles with windows.h included before it.
+#ifdef _WIN32
+#  include <windows.h>
+#endif
+
+#include "fmt/core.h"
+
+#undef min
+#undef max
+
+using fmt::basic_format_arg;
+using fmt::string_view;
+using fmt::internal::buffer;
+using fmt::internal::value;
+
+using testing::_;
+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 ParseContext>
+  auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  typedef std::back_insert_iterator<buffer<Char>> iterator;
+
+  auto format(test_struct, basic_format_context<iterator, char>& ctx)
+      -> decltype(ctx.out()) {
+    const Char* test = "test";
+    return std::copy_n(test, std::strlen(test), ctx.out());
+  }
+};
+FMT_END_NAMESPACE
+
+#if !FMT_GCC_VERSION || FMT_GCC_VERSION >= 470
+TEST(BufferTest, Noncopyable) {
+  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<buffer<char>>::value);
+#  endif
+}
+
+TEST(BufferTest, Nonmoveable) {
+  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<buffer<char>>::value);
+#  endif
+}
+#endif
+
+// A test buffer with a dummy grow method.
+template <typename T> struct test_buffer : buffer<T> {
+  void grow(std::size_t capacity) { this->set(nullptr, capacity); }
+};
+
+template <typename T> struct mock_buffer : buffer<T> {
+  MOCK_METHOD1(do_grow, void(std::size_t capacity));
+
+  void grow(std::size_t capacity) {
+    this->set(this->data(), capacity);
+    do_grow(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(nullptr, &buffer[0]);
+    EXPECT_EQ(static_cast<size_t>(0), buffer.size());
+    EXPECT_EQ(static_cast<size_t>(0), buffer.capacity());
+  }
+  {
+    int dummy;
+    mock_buffer<int> buffer(&dummy);
+    EXPECT_EQ(&dummy, &buffer[0]);
+    EXPECT_EQ(static_cast<size_t>(0), buffer.size());
+    EXPECT_EQ(static_cast<size_t>(0), buffer.capacity());
+  }
+  {
+    int dummy;
+    std::size_t capacity = std::numeric_limits<std::size_t>::max();
+    mock_buffer<int> buffer(&dummy, capacity);
+    EXPECT_EQ(&dummy, &buffer[0]);
+    EXPECT_EQ(static_cast<size_t>(0), buffer.size());
+    EXPECT_EQ(capacity, buffer.capacity());
+  }
+}
+
+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());
+  buffer<int>* buffer = mock_buffer;
+  delete buffer;
+}
+
+TEST(BufferTest, Access) {
+  char data[10];
+  mock_buffer<char> buffer(data, sizeof(data));
+  buffer[0] = 11;
+  EXPECT_EQ(11, buffer[0]);
+  buffer[3] = 42;
+  EXPECT_EQ(42, *(&buffer[0] + 3));
+  const fmt::internal::buffer<char>& const_buffer = buffer;
+  EXPECT_EQ(42, const_buffer[3]);
+}
+
+TEST(BufferTest, Resize) {
+  char data[123];
+  mock_buffer<char> buffer(data, sizeof(data));
+  buffer[10] = 42;
+  EXPECT_EQ(42, buffer[10]);
+  buffer.resize(20);
+  EXPECT_EQ(20u, buffer.size());
+  EXPECT_EQ(123u, buffer.capacity());
+  EXPECT_EQ(42, buffer[10]);
+  buffer.resize(5);
+  EXPECT_EQ(5u, buffer.size());
+  EXPECT_EQ(123u, buffer.capacity());
+  EXPECT_EQ(42, buffer[10]);
+  // Check if resize calls grow.
+  EXPECT_CALL(buffer, do_grow(124));
+  buffer.resize(124);
+  EXPECT_CALL(buffer, do_grow(200));
+  buffer.resize(200);
+}
+
+TEST(BufferTest, Clear) {
+  test_buffer<char> buffer;
+  buffer.resize(20);
+  buffer.resize(0);
+  EXPECT_EQ(static_cast<size_t>(0), buffer.size());
+  EXPECT_EQ(20u, buffer.capacity());
+}
+
+TEST(BufferTest, Append) {
+  char data[15];
+  mock_buffer<char> buffer(data, 10);
+  const char* test = "test";
+  buffer.append(test, test + 5);
+  EXPECT_STREQ(test, &buffer[0]);
+  EXPECT_EQ(5u, buffer.size());
+  buffer.resize(10);
+  EXPECT_CALL(buffer, do_grow(12));
+  buffer.append(test, test + 2);
+  EXPECT_EQ('t', buffer[10]);
+  EXPECT_EQ('e', buffer[11]);
+  EXPECT_EQ(12u, buffer.size());
+}
+
+TEST(BufferTest, AppendAllocatesEnoughStorage) {
+  char data[19];
+  mock_buffer<char> buffer(data, 10);
+  const char* test = "abcdefgh";
+  buffer.resize(10);
+  EXPECT_CALL(buffer, do_grow(19));
+  buffer.append(test, test + 9);
+}
+
+TEST(ArgTest, FormatArgs) {
+  fmt::format_args args;
+  EXPECT_FALSE(args.get(1));
+}
+
+struct custom_context {
+  typedef char char_type;
+
+  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 nullptr;
+    }
+  };
+
+  bool called;
+  fmt::format_parse_context ctx;
+
+  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::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 {
+template <typename Char>
+bool operator==(custom_value<Char> lhs, custom_value<Char> rhs) {
+  return lhs.value == rhs.value;
+}
+}  // namespace internal
+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; };
+
+  mock_visitor() {
+    ON_CALL(*this, visit(_)).WillByDefault(testing::Return(test_result()));
+  }
+
+  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) {
+    unexpected();
+    return test_result();
+  }
+};
+
+template <typename T> struct visit_type { typedef T Type; };
+
+#define VISIT_TYPE(Type_, visit_type_) \
+  template <> struct visit_type<Type_> { typedef visit_type_ Type; }
+
+VISIT_TYPE(signed char, int);
+VISIT_TYPE(unsigned char, unsigned);
+VISIT_TYPE(short, int);
+VISIT_TYPE(unsigned short, unsigned);
+
+#if LONG_MAX == INT_MAX
+VISIT_TYPE(long, int);
+VISIT_TYPE(unsigned long, unsigned);
+#else
+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));                                    \
+    typedef std::back_insert_iterator<buffer<Char>> iterator;                 \
+    fmt::visit_format_arg(                                                    \
+        visitor, make_arg<fmt::basic_format_context<iterator, Char>>(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 {};
+
+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() {
+  return static_cast<T>(42);
+}
+
+template <typename T>
+typename std::enable_if<std::is_floating_point<T>::value, T>::type
+test_value() {
+  return static_cast<T>(4.2);
+}
+
+TYPED_TEST(NumericArgTest, MakeAndVisit) {
+  CHECK_ARG(test_value<TypeParam>(), typename);
+  CHECK_ARG(std::numeric_limits<TypeParam>::min(), typename);
+  CHECK_ARG(std::numeric_limits<TypeParam>::max(), typename);
+}
+
+TEST(ArgTest, CharArg) {
+  CHECK_ARG_(char, 'a', 'a');
+  CHECK_ARG_(wchar_t, L'a', 'a');
+  CHECK_ARG_(wchar_t, L'a', L'a');
+}
+
+TEST(ArgTest, StringArg) {
+  char str_data[] = "test";
+  char* str = str_data;
+  const char* cstr = str;
+  CHECK_ARG_(char, cstr, str);
+
+  string_view sref(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;
+
+  fmt::wstring_view sref(str);
+  CHECK_ARG_(wchar_t, cstr, str);
+  CHECK_ARG_(wchar_t, cstr, cstr);
+  CHECK_ARG_(wchar_t, sref, std::wstring(str));
+  CHECK_ARG_(wchar_t, sref, fmt::wstring_view(str));
+}
+
+TEST(ArgTest, PointerArg) {
+  void* p = nullptr;
+  const void* cp = nullptr;
+  CHECK_ARG_(char, cp, p);
+  CHECK_ARG_(wchar_t, cp, p);
+  CHECK_ARG(cp, );
+}
+
+struct check_custom {
+  test_result operator()(
+      fmt::basic_format_arg<fmt::format_context>::handle h) const {
+    struct test_buffer : fmt::internal::buffer<char> {
+      char data[10];
+      test_buffer() : fmt::internal::buffer<char>(data, 0, 10) {}
+      void grow(std::size_t) {}
+    } buffer;
+    fmt::internal::buffer<char>& base = buffer;
+    fmt::format_parse_context parse_ctx("");
+    fmt::format_context ctx(std::back_inserter(base), fmt::format_args());
+    h.format(parse_ctx, ctx);
+    EXPECT_EQ("test", std::string(buffer.data, buffer.size()));
+    return test_result();
+  }
+};
+
+TEST(ArgTest, CustomArg) {
+  test_struct test;
+  typedef mock_visitor<fmt::basic_format_arg<fmt::format_context>::handle>
+      visitor;
+  testing::StrictMock<visitor> v;
+  EXPECT_CALL(v, visit(_)).WillOnce(testing::Invoke(check_custom()));
+  fmt::visit_format_arg(v, make_arg<fmt::format_context>(test));
+}
+
+TEST(ArgTest, VisitInvalidArg) {
+  testing::StrictMock<mock_visitor<fmt::monostate>> visitor;
+  EXPECT_CALL(visitor, visit(_));
+  fmt::basic_format_arg<fmt::format_context> arg;
+  fmt::visit_format_arg(visitor, arg);
+}
+
+TEST(StringViewTest, Length) {
+  // Test that StringRef::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) {
+      string_view lhs(inputs[i]), rhs(inputs[j]);
+      EXPECT_EQ(Op<int>()(lhs.compare(rhs), 0), Op<string_view>()(lhs, rhs));
+    }
+  }
+}
+
+TEST(StringViewTest, Compare) {
+  EXPECT_EQ(string_view("foo").compare(string_view("foo")), 0);
+  EXPECT_GT(string_view("fop").compare(string_view("foo")), 0);
+  EXPECT_LT(string_view("foo").compare(string_view("fop")), 0);
+  EXPECT_GT(string_view("foo").compare(string_view("fo")), 0);
+  EXPECT_LT(string_view("fo").compare(string_view("foo")), 0);
+  check_op<std::equal_to>();
+  check_op<std::not_equal_to>();
+  check_op<std::less>();
+  check_op<std::less_equal>();
+  check_op<std::greater>();
+  check_op<std::greater_equal>();
+}
+
+struct enabled_formatter {};
+struct disabled_formatter {};
+struct disabled_formatter_convertible {
+  operator int() const { return 42; }
+};
+
+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::internal::has_formatter;
+  using context = fmt::format_context;
+  EXPECT_TRUE((has_formatter<enabled_formatter, context>::value));
+  EXPECT_FALSE((has_formatter<disabled_formatter, context>::value));
+  EXPECT_FALSE((has_formatter<disabled_formatter_convertible, context>::value));
+}
+
+struct convertible_to_int {
+  operator int() const { return 42; }
+};
+
+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());
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(CoreTest, FormatterOverridesImplicitConversion) {
+  EXPECT_EQ(fmt::format("{}", convertible_to_int()), "foo");
+}
+
+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(); }
+
+ private:
+  std::basic_string<Char> s_;
+};
+
+template <typename Char>
+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()); }
+
+ 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())};
+}
+}  // namespace FakeQt
+
+template <typename T> class IsStringTest : public testing::Test {};
+
+typedef ::testing::Types<char, wchar_t, char16_t, char32_t> StringCharTypes;
+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::internal::is_string<fmt::basic_string_view<TypeParam>>::value);
+  EXPECT_TRUE(
+      fmt::internal::is_string<derived_from_string_view<TypeParam>>::value);
+  using string_view = fmt::internal::std_string_view<TypeParam>;
+  EXPECT_TRUE(std::is_empty<string_view>::value !=
+              fmt::internal::is_string<string_view>::value);
+  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);
+}
+
+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
+#endif
+  EXPECT_EQ(fmt::format("{}", 42), "42");
+}
+
+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
+#endif
+  std::string s;
+  fmt::format_to(std::back_inserter(s), "{}", 42);
+  EXPECT_EQ(s, "42");
+}
+
+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::mapped_type_constant<my_string<char>,
+                                          fmt::format_context>::value;
+  EXPECT_EQ(type, fmt::internal::string_type);
+  type = fmt::internal::mapped_type_constant<my_string<wchar_t>,
+                                             fmt::wformat_context>::value;
+  EXPECT_EQ(type, fmt::internal::string_type);
+  type =
+      fmt::internal::mapped_type_constant<QString, fmt::wformat_context>::value;
+  EXPECT_EQ(type, fmt::internal::string_type);
+  // Does not compile: only wide format contexts are compatible with QString!
+  // type = fmt::internal::mapped_type_constant<QString,
+  // fmt::format_context>::value;
+}
+
+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) {
+  EXPECT_EQ("foo", fmt::format("{}", implicitly_convertible_to_string_view()));
+}
+
+// std::is_constructible is broken in MSVC until version 2015.
+#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) {
+  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"; }
+};
+
+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>
+  explicit operator String() const {
+    return String("foo", 3u);
+  }
+};
+
+TEST(FormatterTest, FormatExplicitlyConvertibleToStringLike) {
+  EXPECT_EQ("foo", fmt::format("{}", explicitly_convertible_to_string_like()));
+}
+#endif

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

@@ -5,6 +5,10 @@
 //
 // For the license information refer to format.h.
 
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS
+#endif
+
 #include "fmt/format.h"
 #include "gtest-extra.h"
 
@@ -13,21 +17,22 @@
 
 // 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>> {
+class custom_arg_formatter
+    : public fmt::arg_formatter<fmt::buffer_range<char>> {
  public:
-  typedef fmt::back_insert_range<fmt::internal::buffer> range;
+  using range = fmt::buffer_range<char>;
   typedef fmt::arg_formatter<range> base;
 
-  custom_arg_formatter(fmt::format_context &ctx, fmt::format_specs &s)
-  : base(ctx, s) {}
+  custom_arg_formatter(fmt::format_context& ctx,
+                       fmt::format_parse_context* parse_ctx,
+                       fmt::format_specs* s = nullptr)
+      : base(ctx, parse_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;
+    // Comparing a float to 0.0 is safe.
+    if (round(value * pow(10, specs()->precision)) == 0.0) value = 0;
     return base::operator()(value);
   }
 };
@@ -40,7 +45,7 @@ std::string custom_vformat(fmt::string_view format_str, fmt::format_args args) {
 }
 
 template <typename... Args>
-std::string custom_format(const char *format_str, const Args & ... 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/format

@@ -0,0 +1,861 @@
+// 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 <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 */ std::back_insert_iterator<fmt::internal::buffer<char>>, char>;
+  using wformat_context = basic_format_context<
+    /* unspecified */ std::back_insert_iterator<fmt::internal::buffer<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<Out, char> args);
+  template<class Out>
+    Out vformat_to(Out out, wstring_view fmt, format_args_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::internal::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 Range>
+class arg_formatter
+    : public fmt::internal::arg_formatter_base<Range, error_handler> {
+ private:
+  using char_type = typename Range::value_type;
+  using base = fmt::internal::arg_formatter_base<Range, error_handler>;
+  using format_context = std::basic_format_context<typename base::iterator, char_type>;
+  using parse_context = basic_format_parse_context<char_type>;
+
+  parse_context* parse_ctx_;
+  format_context& ctx_;
+
+ public:
+  typedef Range range;
+  typedef typename base::iterator iterator;
+  typedef typename base::format_specs 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(Range(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::internal::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::internal::none_type;
+    if (std::is_same_v<T, bool>)
+      return fmt::internal::bool_type;
+    if (std::is_same_v<T, char_type>)
+      return fmt::internal::char_type;
+    if (std::is_same_v<T, int>)
+      return fmt::internal::int_type;
+    if (std::is_same_v<T, unsigned int>)
+      return fmt::internal::uint_type;
+    if (std::is_same_v<T, long long int>)
+      return fmt::internal::long_long_type;
+    if (std::is_same_v<T, unsigned long long int>)
+      return fmt::internal::ulong_long_type;
+    if (std::is_same_v<T, double>)
+      return fmt::internal::double_type;
+    if (std::is_same_v<T, long double>)
+      return fmt::internal::long_double_type;
+    if (std::is_same_v<T, const char_type*>)
+      return fmt::internal::cstring_type;
+    if (std::is_same_v<T, basic_string_view<char_type>>)
+      return fmt::internal::string_type;
+    if (std::is_same_v<T, const void*>)
+      return fmt::internal::pointer_type;
+    assert(get_value(arg).index() == 12);
+    return fmt::internal::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 {
+  typedef typename ArgFormatter::range range;
+
+  format_handler(range r, basic_string_view<Char> str,
+                 basic_format_args<Context> format_args,
+                 fmt::internal::locale_ref loc)
+      : parse_ctx(str), context(r.begin(), format_args, loc) {}
+
+  void on_text(const Char* begin, const Char* end) {
+    auto size = fmt::internal::to_unsigned(end - begin);
+    auto out = context.out();
+    auto&& it = fmt::internal::reserve(out, size);
+    it = std::copy_n(begin, size, it);
+    context.advance_to(out);
+  }
+
+  void on_arg_id() {
+    arg = context.arg(parse_ctx.next_arg_id());
+  }
+  void on_arg_id(unsigned id) {
+    parse_ctx.check_arg_id(id);
+    arg = context.arg(id);
+  }
+  void on_arg_id(fmt::basic_string_view<Char>) {}
+
+  void on_replacement_field(const Char* p) {
+    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(const Char* begin, const Char* end) {
+    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::internal::specs_handler;
+    using parse_context = basic_format_parse_context<Char>;
+    fmt::internal::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;
+  basic_format_arg<Context> arg;
+};
+
+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 internal = fmt::internal;
+    typedef internal::dynamic_specs_handler<ParseContext> handler_type;
+    auto type = internal::mapped_type_constant<T, fmt::buffer_context<Char>>::value;
+    internal::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 internal::none_type:
+    case internal::named_arg_type:
+      FMT_ASSERT(false, "invalid argument type");
+      break;
+    case internal::int_type:
+    case internal::uint_type:
+    case internal::long_long_type:
+    case internal::ulong_long_type:
+    case internal::bool_type:
+      handle_int_type_spec(type_spec,
+                           internal::int_type_checker<decltype(eh)>(eh));
+      break;
+    case internal::char_type:
+      handle_char_specs(
+          &specs_, internal::char_specs_checker<decltype(eh)>(type_spec, eh));
+      break;
+    case internal::double_type:
+    case internal::long_double_type:
+      handle_float_type_spec(type_spec,
+                             internal::float_type_checker<decltype(eh)>(eh));
+      break;
+    case internal::cstring_type:
+      internal::handle_cstring_type_spec(
+          type_spec, internal::cstring_type_checker<decltype(eh)>(eh));
+      break;
+    case internal::string_type:
+      internal::check_string_type_spec(type_spec, eh);
+      break;
+    case internal::pointer_type:
+      internal::check_pointer_type_spec(type_spec, eh);
+      break;
+    case internal::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::internal::handle_dynamic_spec<fmt::internal::width_checker>(
+        specs_.width, specs_.width_ref, ctx);
+    fmt::internal::handle_dynamic_spec<fmt::internal::precision_checker>(
+        specs_.precision, specs_.precision_ref, ctx);
+    using range_type = fmt::internal::output_range<typename FormatContext::iterator,
+                         typename FormatContext::char_type>;
+    return visit_format_arg(arg_formatter<range_type>(ctx, nullptr, &specs_),
+                            basic_format_arg<FormatContext>(val));
+  }
+
+ private:
+  fmt::internal::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::internal::buffer<char>& buf = mbuf;
+  using range = fmt::buffer_range<char>;
+  detail::format_handler<detail::arg_formatter<range>, char, format_context>
+    h(range(std::back_inserter(buf)), fmt, args, {});
+  fmt::internal::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<Out, char> args) {
+    using range = fmt::internal::output_range<Out, char>;
+    detail::format_handler<detail::arg_formatter<range>, char, basic_format_context<Out, char>>
+      h(range(out), fmt, args, {});
+    fmt::internal::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<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

@@ -5,7 +5,6 @@
 //
 // For the license information refer to format.h.
 
-#define FMT_EXTENDED_COLORS
 #define FMT_NOEXCEPT
 #undef FMT_SHARED
 #include "test-assert.h"
@@ -21,42 +20,206 @@
 #include "gtest-extra.h"
 #include "util.h"
 
-#undef min
 #undef max
 
-template <typename T>
-struct ValueExtractor: fmt::internal::function<T> {
-  T operator()(T value) {
-    return value;
-  }
+using fmt::internal::bigint;
+using fmt::internal::fp;
+using fmt::internal::max_value;
 
-  template <typename U>
-  FMT_NORETURN T operator()(U) {
+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, 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);
+  n *= 1;
+  EXPECT_EQ("42", fmt::format("{}", n));
+  n *= 2;
+  EXPECT_EQ("84", fmt::format("{}", n));
+  n *= 0x12345678;
+  EXPECT_EQ("962fc95e0", fmt::format("{}", n));
+  auto max = max_value<uint32_t>();
+  bigint bigmax(max);
+  bigmax *= max;
+  EXPECT_EQ("fffffffe00000001", fmt::format("{}", bigmax));
+}
+
+template <bool is_iec559> void test_construct_from_double() {
+  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);
+}
+
+TEST(FPTest, ConstructFromDouble) {
+  test_construct_from_double<std::numeric_limits<double>::is_iec559>();
+}
+
+TEST(FPTest, Normalize) {
+  const auto v = fp(0xbeef, 42);
+  auto normalized = normalize(v);
+  EXPECT_EQ(0xbeef000000000000, normalized.f);
+  EXPECT_EQ(-6, normalized.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);
+}
+
+TEST(FPTest, Multiply) {
+  auto v = fp(123ULL << 32, 4) * fp(56ULL << 32, 7);
+  EXPECT_EQ(v.f, 123u * 56u);
+  EXPECT_EQ(v.e, 4 + 7 + 64);
+  v = fp(123ULL << 32, 4) * fp(567ULL << 31, 8);
+  EXPECT_EQ(v.f, (123 * 567 + 1u) / 2);
+  EXPECT_EQ(v.e, 4 + 8 + 64);
+}
+
+TEST(FPTest, GetCachedPower) {
+  typedef std::numeric_limits<double> limits;
+  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(static_cast<double>(fp.f), fp.e));
+  }
+}
+
+TEST(FPTest, GetRoundDirection) {
+  using fmt::internal::get_round_direction;
+  EXPECT_EQ(fmt::internal::down, get_round_direction(100, 50, 0));
+  EXPECT_EQ(fmt::internal::up, get_round_direction(100, 51, 0));
+  EXPECT_EQ(fmt::internal::down, get_round_direction(100, 40, 10));
+  EXPECT_EQ(fmt::internal::up, get_round_direction(100, 60, 10));
+  for (int i = 41; i < 60; ++i)
+    EXPECT_EQ(fmt::internal::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(fmt::internal::up, get_round_direction(max, max - 1, 2));
+  // Check that 2 * (remainder + error) doesn't overflow.
+  EXPECT_EQ(fmt::internal::unknown,
+            get_round_direction(max, max / 2 + 1, max / 2));
+  // Check that remainder - error doesn't overflow.
+  EXPECT_EQ(fmt::internal::unknown, get_round_direction(100, 40, 41));
+  // Check that 2 * (remainder - error) doesn't overflow.
+  EXPECT_EQ(fmt::internal::up, get_round_direction(max, max - 1, 1));
+}
+
+TEST(FPTest, FixedHandler) {
+  struct handler : fmt::internal::fixed_handler {
+    char buffer[10];
+    handler(int prec = 0) : fmt::internal::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::internal::digits;
+  EXPECT_EQ(handler(1).on_digit('0', 100, 10, 10, exp, false), digits::done);
+  // 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;
+  int exp = 0;
+  grisu_format(4.2f, buf, -1, false, exp);
+}
+
+template <typename T> struct value_extractor {
+  T operator()(T value) { return value; }
+
+  template <typename U> FMT_NORETURN T operator()(U) {
     throw std::runtime_error(fmt::format("invalid type {}", typeid(U).name()));
   }
+
+#ifdef __apple_build_version__
+  // Apple Clang does not define typeid for __int128_t and __uint128_t.
+  FMT_NORETURN T operator()(__int128_t) {
+    throw std::runtime_error(fmt::format("invalid type {}", "__int128_t"));
+  }
+
+  FMT_NORETURN T operator()(__uint128_t) {
+    throw std::runtime_error(fmt::format("invalid type {}", "__uint128_t"));
+  }
+#endif
 };
 
 TEST(FormatTest, ArgConverter) {
-  long long value = std::numeric_limits<long long>::max();
+  long long value = max_value<long long>();
   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));
+  fmt::visit_format_arg(
+      fmt::internal::arg_converter<long long, fmt::format_context>(arg, 'd'),
+      arg);
+  EXPECT_EQ(value, fmt::visit_format_arg(value_extractor<long long>(), arg));
 }
 
 TEST(FormatTest, FormatNegativeNaN) {
   double nan = std::numeric_limits<double>::quiet_NaN();
-  if (fmt::internal::fputil::isnegative(-nan))
+  if (std::signbit(-nan))
     EXPECT_EQ("-nan", fmt::format("{}", -nan));
   else
     fmt::print("Warning: compiler doesn't handle negative NaN correctly");
 }
 
 TEST(FormatTest, StrError) {
-  char *message = nullptr;
+  char* message = nullptr;
   char buffer[BUFFER_SIZE];
-  EXPECT_ASSERT(fmt::safe_strerror(EDOM, message = nullptr, 0), "invalid buffer");
-  EXPECT_ASSERT(fmt::safe_strerror(EDOM, message = buffer, 0),
+  EXPECT_ASSERT(fmt::internal::safe_strerror(EDOM, message = nullptr, 0),
+                "invalid buffer");
+  EXPECT_ASSERT(fmt::internal::safe_strerror(EDOM, message = buffer, 0),
                 "invalid buffer");
   buffer[0] = 'x';
 #if defined(_GNU_SOURCE) && !defined(__COVERITY__)
@@ -67,17 +230,19 @@ TEST(FormatTest, StrError) {
   int error_code = EDOM;
 #endif
 
-  int result = fmt::safe_strerror(error_code, message = buffer, BUFFER_SIZE);
-  EXPECT_EQ(0, result);
+  int result =
+      fmt::internal::safe_strerror(error_code, message = buffer, BUFFER_SIZE);
+  EXPECT_EQ(result, 0);
   std::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::internal::safe_strerror(error_code, message = buffer, message_size);
   EXPECT_EQ(ERANGE, result);
-  result = fmt::safe_strerror(error_code, message = buffer, 1);
+  result = fmt::internal::safe_strerror(error_code, message = buffer, 1);
   EXPECT_EQ(buffer, message);  // Message should point to buffer.
   EXPECT_EQ(ERANGE, result);
   EXPECT_STREQ("", message);
@@ -89,14 +254,14 @@ TEST(FormatTest, FormatErrorCode) {
   {
     fmt::memory_buffer buffer;
     format_to(buffer, "garbage");
-    fmt::format_error_code(buffer, 42, "test");
+    fmt::internal::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::internal::format_error_code(buffer, 42, prefix);
     EXPECT_EQ(msg, to_string(buffer));
   }
   int codes[] = {42, -1};
@@ -104,23 +269,44 @@ TEST(FormatTest, FormatErrorCode) {
     // 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::internal::format_error_code(buffer, codes[i], prefix);
     EXPECT_EQ(prefix + sep + msg, to_string(buffer));
     std::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::internal::format_error_code(buffer, codes[i], prefix);
     EXPECT_EQ(msg, to_string(buffer));
   }
 }
 
-TEST(ColorsTest, Colors) {
-  EXPECT_WRITE(stdout, fmt::print(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(fmt::color::blue,"blue"),
-               "\x1b[38;2;000;000;255mblue\x1b[0m");
+TEST(FormatTest, CountCodePoints) {
+  EXPECT_EQ(4, fmt::internal::count_code_points(fmt::u8string_view("ёжик")));
+}
+
+// Tests fmt::internal::count_digits for integer type Int.
+template <typename Int> void test_count_digits() {
+  for (Int i = 0; i < 10; ++i) EXPECT_EQ(1u, fmt::internal::count_digits(i));
+  for (Int i = 1, n = 1, end = max_value<Int>() / 10; n <= end;
+       ++i) {
+    n *= 10;
+    EXPECT_EQ(i, fmt::internal::count_digits(n - 1));
+    EXPECT_EQ(i + 1, fmt::internal::count_digits(n));
+  }
+}
+
+TEST(UtilTest, CountDigits) {
+  test_count_digits<uint32_t>();
+  test_count_digits<uint64_t>();
+}
+
+TEST(UtilTest, WriteUIntPtr) {
+  fmt::memory_buffer buf;
+  fmt::internal::writer writer(buf);
+  writer.write_pointer(fmt::internal::bit_cast<fmt::internal::fallback_uintptr>(
+                           reinterpret_cast<void*>(0xface)),
+                       nullptr);
+  EXPECT_EQ("0xface", to_string(buf));
 }

test/fuzzing/.gitignore

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

test/fuzzing/CMakeLists.txt

@@ -0,0 +1,38 @@
+# Copyright (c) 2019, Paul Dreik
+# License: see LICENSE.rst in the fmt root directory
+
+# settings this links in a main. 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")
+
+# Find all fuzzers.
+set(SOURCES
+  chrono_duration.cpp
+  named_arg.cpp
+  one_arg.cpp
+  sprintf.cpp
+  two_args.cpp
+)
+
+macro(implement_fuzzer sourcefile)
+  get_filename_component(basename ${sourcefile} NAME_WE)
+  set(name fuzzer_${basename})
+  add_executable(${name} ${sourcefile} fuzzer_common.h)
+  if (FMT_FUZZ_LINKMAIN)
+      target_sources(${name} PRIVATE main.cpp)
+  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)
+endmacro ()
+
+foreach (X IN ITEMS ${SOURCES})
+  implement_fuzzer(${X})
+endforeach ()

test/fuzzing/README.md

@@ -0,0 +1,43 @@
+# FMT Fuzzer
+
+Fuzzing has revealed [several bugs](https://github.com/fmtlib/fmt/issues?&q=is%3Aissue+fuzz)
+in fmt. It is a part of the continous fuzzing at
+[oss-fuzz](https://github.com/google/oss-fuzz).
+
+The source code is modified to make the fuzzing possible without locking up on
+resource exhaustion:
+```cpp
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+if(spec.precision>100000) {
+  throw std::runtime_error("fuzz mode - avoiding large precision");
+}
+#endif
+```
+This macro is the defacto standard for making fuzzing practically possible, see
+[the libFuzzer documentation](https://llvm.org/docs/LibFuzzer.html#fuzzer-friendly-build-mode).
+
+## 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 +1,110 @@
+#!/bin/sh
+#
+# Creates fuzzer builds of various kinds
+# - reproduce mode (no fuzzing, just enables replaying data through the fuzzers)
+# - 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
+#
+# License: see LICENSE.rst in the fmt root directory
+
+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"
+
+#builds the fuzzers as one would do if using afl or just making
+#binaries for reproducing.
+builddir=$here/build-fuzzers-reproduce
+mkdir -p $builddir
+cd $builddir
+CXX="ccache g++" CXXFLAGS="$CXXFLAGSALL" cmake \
+$CMAKEFLAGSALL
+cmake --build $builddir
+
+#for performance analysis of the fuzzers
+builddir=$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 $builddir
+
+#builds fuzzers for local fuzzing with libfuzzer with asan only
+builddir=$here/build-fuzzers-libfuzzer-addr
+mkdir -p $builddir
+cd $builddir
+CXX="clang++" \
+CXXFLAGS="$CXXFLAGSALL -fsanitize=fuzzer-no-link,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.cpp

@@ -0,0 +1,152 @@
+// Copyright (c) 2019, Paul Dreik
+// License: see LICENSE.rst in the fmt root directory
+
+#include <fmt/chrono.h>
+#include <cstdint>
+#include <limits>
+#include <stdexcept>
+#include <type_traits>
+#include <vector>
+#include "fuzzer_common.h"
+
+template <typename Item, typename Ratio>
+void invoke_inner(fmt::string_view formatstring, const Item item) {
+  const std::chrono::duration<Item, Ratio> value(item);
+  try {
+#if FMT_FUZZ_FORMAT_TO_STRING
+    std::string message = fmt::format(formatstring, value);
+#else
+    fmt::memory_buffer buf;
+    fmt::format_to(buf, formatstring, value);
+#endif
+  } catch (std::exception& /*e*/) {
+  }
+}
+
+// Item is the underlying type for duration (int, long etc)
+template <typename Item>
+void invoke_outer(const uint8_t* Data, std::size_t Size, const int scaling) {
+  // always use a fixed location of the data
+  using fmt_fuzzer::Nfixed;
+
+  constexpr auto N = sizeof(Item);
+  static_assert(N <= Nfixed, "fixed size is too small");
+  if (Size <= Nfixed + 1) {
+    return;
+  }
+
+  const Item item = fmt_fuzzer::assignFromBuf<Item>(Data);
+
+  // fast forward
+  Data += Nfixed;
+  Size -= Nfixed;
+
+  // Data is already allocated separately in libFuzzer so reading past
+  // the end will most likely be detected anyway
+  const auto formatstring = fmt::string_view(fmt_fuzzer::as_chars(Data), Size);
+
+  // doit_impl<Item,std::yocto>(buf.data(),item);
+  // doit_impl<Item,std::zepto>(buf.data(),item);
+  switch (scaling) {
+  case 1:
+    invoke_inner<Item, std::atto>(formatstring, item);
+    break;
+  case 2:
+    invoke_inner<Item, std::femto>(formatstring, item);
+    break;
+  case 3:
+    invoke_inner<Item, std::pico>(formatstring, item);
+    break;
+  case 4:
+    invoke_inner<Item, std::nano>(formatstring, item);
+    break;
+  case 5:
+    invoke_inner<Item, std::micro>(formatstring, item);
+    break;
+  case 6:
+    invoke_inner<Item, std::milli>(formatstring, item);
+    break;
+  case 7:
+    invoke_inner<Item, std::centi>(formatstring, item);
+    break;
+  case 8:
+    invoke_inner<Item, std::deci>(formatstring, item);
+    break;
+  case 9:
+    invoke_inner<Item, std::deca>(formatstring, item);
+    break;
+  case 10:
+    invoke_inner<Item, std::kilo>(formatstring, item);
+    break;
+  case 11:
+    invoke_inner<Item, std::mega>(formatstring, item);
+    break;
+  case 12:
+    invoke_inner<Item, std::giga>(formatstring, item);
+    break;
+  case 13:
+    invoke_inner<Item, std::tera>(formatstring, item);
+    break;
+  case 14:
+    invoke_inner<Item, std::peta>(formatstring, item);
+    break;
+  case 15:
+    invoke_inner<Item, std::exa>(formatstring, item);
+  }
+  // doit_impl<Item,std::zeta>(buf.data(),item);
+  // doit_impl<Item,std::yotta>(buf.data(),item);
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* Data, std::size_t Size) {
+  if (Size <= 4) {
+    return 0;
+  }
+
+  const auto representation = Data[0];
+  const auto scaling = Data[1];
+  Data += 2;
+  Size -= 2;
+
+  switch (representation) {
+  case 1:
+    invoke_outer<char>(Data, Size, scaling);
+    break;
+  case 2:
+    invoke_outer<unsigned char>(Data, Size, scaling);
+    break;
+  case 3:
+    invoke_outer<signed char>(Data, Size, scaling);
+    break;
+  case 4:
+    invoke_outer<short>(Data, Size, scaling);
+    break;
+  case 5:
+    invoke_outer<unsigned short>(Data, Size, scaling);
+    break;
+  case 6:
+    invoke_outer<int>(Data, Size, scaling);
+    break;
+  case 7:
+    invoke_outer<unsigned int>(Data, Size, scaling);
+    break;
+  case 8:
+    invoke_outer<long>(Data, Size, scaling);
+    break;
+  case 9:
+    invoke_outer<unsigned long>(Data, Size, scaling);
+    break;
+  case 10:
+    invoke_outer<float>(Data, Size, scaling);
+    break;
+  case 11:
+    invoke_outer<double>(Data, Size, scaling);
+    break;
+  case 12:
+    invoke_outer<long double>(Data, Size, scaling);
+    break;
+  default:
+    break;
+  }
+
+  return 0;
+}

test/fuzzing/fuzzer_common.h

@@ -0,0 +1,67 @@
+#ifndef FUZZER_COMMON_H
+#define FUZZER_COMMON_H
+
+// Copyright (c) 2019, Paul Dreik
+// License: see LICENSE.rst in the fmt root directory
+
+#include <cstdint>      // std::uint8_t
+#include <cstring>      // memcpy
+#include <type_traits>  // trivially copyable
+
+// one can format to either a string, or a buf. buf 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
+
+// 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.
+// For this, we must know the size of the largest possible type in use.
+
+// There are some problems on travis, claiming Nfixed is not a constant
+// expression which seems to be an issue with older versions of libstdc++
+#if _GLIBCXX_RELEASE >= 7
+#  include <algorithm>
+namespace fmt_fuzzer {
+constexpr auto Nfixed = std::max(sizeof(long double), sizeof(std::intmax_t));
+}
+#else
+namespace fmt_fuzzer {
+constexpr auto Nfixed = 16;
+}
+#endif
+
+namespace fmt_fuzzer {
+// view data as a c char pointer.
+template <typename T> inline const char* as_chars(const T* data) {
+  return static_cast<const char*>(static_cast<const void*>(data));
+}
+
+// view data as a byte pointer
+template <typename T> inline const std::uint8_t* as_bytes(const T* data) {
+  return static_cast<const std::uint8_t*>(static_cast<const void*>(data));
+}
+
+// blits bytes from Data to form an (assumed trivially constructible) object
+// of type Item
+template <class Item> inline Item assignFromBuf(const std::uint8_t* Data) {
+  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 assignFromBuf<bool>(const std::uint8_t* Data) {
+  return !!Data[0];
+}
+
+}  // namespace fmt_fuzzer
+
+#endif  // FUZZER_COMMON_H

test/fuzzing/main.cpp

@@ -0,0 +1,21 @@
+#include <cassert>
+#include <fstream>
+#include <sstream>
+#include <vector>
+#include "fuzzer_common.h"
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* Data, std::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 pos = in.tellg();
+    assert(pos >= 0);
+    in.seekg(0, std::ios_base::beg);
+    std::vector<char> buf(static_cast<std::size_t>(pos));
+    in.read(buf.data(), static_cast<long>(buf.size()));
+    assert(in.gcount() == pos);
+    LLVMFuzzerTestOneInput(fmt_fuzzer::as_bytes(buf.data()), buf.size());
+  }
+}

test/fuzzing/named_arg.cpp

@@ -0,0 +1,128 @@
+// Copyright (c) 2019, Paul Dreik
+// License: see LICENSE.rst in the fmt root directory
+
+#include <fmt/chrono.h>
+#include <fmt/core.h>
+#include <cstdint>
+#include <stdexcept>
+#include <type_traits>
+#include <vector>
+#include "fuzzer_common.h"
+
+template <typename Item1>
+void invoke_fmt(const uint8_t* Data, std::size_t Size, unsigned int argsize) {
+  constexpr auto N1 = sizeof(Item1);
+  static_assert(N1 <= fmt_fuzzer::Nfixed, "Nfixed too small");
+  if (Size <= fmt_fuzzer::Nfixed) {
+    return;
+  }
+  const Item1 item1 = fmt_fuzzer::assignFromBuf<Item1>(Data);
+
+  Data += fmt_fuzzer::Nfixed;
+  Size -= fmt_fuzzer::Nfixed;
+
+  // how many chars should be used for the argument name?
+  if (argsize <= 0 || argsize >= Size) {
+    return;
+  }
+
+  // allocating buffers separately is slower, but increases chances
+  // of detecting memory errors
+#if FMT_FUZZ_SEPARATE_ALLOCATION
+  std::vector<char> argnamebuffer(argsize);
+  std::memcpy(argnamebuffer.data(), Data, argsize);
+  auto argname = fmt::string_view(argnamebuffer.data(), argsize);
+#else
+  auto argname = fmt::string_view(fmt_fuzzer::as_chars(Data), argsize);
+#endif
+  Data += argsize;
+  Size -= argsize;
+
+#if FMT_FUZZ_SEPARATE_ALLOCATION
+  // allocates as tight as possible, making it easier to catch buffer overruns.
+  std::vector<char> fmtstringbuffer(Size);
+  std::memcpy(fmtstringbuffer.data(), Data, Size);
+  auto fmtstring = fmt::string_view(fmtstringbuffer.data(), Size);
+#else
+  auto fmtstring = fmt::string_view(fmt_fuzzer::as_chars(Data), Size);
+#endif
+
+#if FMT_FUZZ_FORMAT_TO_STRING
+  std::string message = fmt::format(fmtstring, fmt::arg(argname, item1));
+#else
+  fmt::memory_buffer outbuf;
+  fmt::format_to(outbuf, fmtstring, fmt::arg(argname, item1));
+#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;
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* Data, std::size_t Size) {
+  if (Size <= 3) {
+    return 0;
+  }
+
+  // switch types depending on the first byte of the input
+  const auto first = Data[0] & 0x0F;
+  const unsigned int second = (Data[0] & 0xF0) >> 4;
+  Data++;
+  Size--;
+
+  auto outerfcn = [=](auto param1) {
+    invoke_fmt<decltype(param1)>(Data, Size, second);
+  };
+
+  try {
+    invoke(first, outerfcn);
+  } catch (std::exception& /*e*/) {
+  }
+  return 0;
+}

test/fuzzing/one_arg.cpp

@@ -0,0 +1,131 @@
+// Copyright (c) 2019, Paul Dreik
+// License: see LICENSE.rst in the fmt root directory
+
+#include <fmt/core.h>
+#include <cstdint>
+#include <stdexcept>
+#include <type_traits>
+#include <vector>
+
+#include <fmt/chrono.h>
+#include "fuzzer_common.h"
+
+using fmt_fuzzer::Nfixed;
+
+template <typename Item>
+void invoke_fmt(const uint8_t* Data, std::size_t Size) {
+  constexpr auto N = sizeof(Item);
+  static_assert(N <= Nfixed, "Nfixed is too small");
+  if (Size <= Nfixed) {
+    return;
+  }
+  const Item item = fmt_fuzzer::assignFromBuf<Item>(Data);
+  Data += Nfixed;
+  Size -= Nfixed;
+
+#if FMT_FUZZ_SEPARATE_ALLOCATION
+  // allocates as tight as possible, making it easier to catch buffer overruns.
+  std::vector<char> fmtstringbuffer(Size);
+  std::memcpy(fmtstringbuffer.data(), Data, Size);
+  auto fmtstring = fmt::string_view(fmtstringbuffer.data(), Size);
+#else
+  auto fmtstring = fmt::string_view(fmt_fuzzer::as_chars(Data), Size);
+#endif
+
+#if FMT_FUZZ_FORMAT_TO_STRING
+  std::string message = fmt::format(fmtstring, item);
+#else
+  fmt::memory_buffer message;
+  fmt::format_to(message, fmtstring, item);
+#endif
+}
+
+void invoke_fmt_time(const uint8_t* Data, std::size_t Size) {
+  using Item = std::time_t;
+  constexpr auto N = sizeof(Item);
+  static_assert(N <= Nfixed, "Nfixed too small");
+  if (Size <= Nfixed) {
+    return;
+  }
+  const Item item = fmt_fuzzer::assignFromBuf<Item>(Data);
+  Data += Nfixed;
+  Size -= Nfixed;
+#if FMT_FUZZ_SEPARATE_ALLOCATION
+  // allocates as tight as possible, making it easier to catch buffer overruns.
+  std::vector<char> fmtstringbuffer(Size);
+  std::memcpy(fmtstringbuffer.data(), Data, Size);
+  auto fmtstring = fmt::string_view(fmtstringbuffer.data(), Size);
+#else
+  auto fmtstring = fmt::string_view(fmt_fuzzer::as_chars(Data), Size);
+#endif
+  auto* b = std::localtime(&item);
+  if (b) {
+#if FMT_FUZZ_FORMAT_TO_STRING
+    std::string message = fmt::format(fmtstring, *b);
+#else
+    fmt::memory_buffer message;
+    fmt::format_to(message, fmtstring, *b);
+#endif
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* Data, std::size_t Size) {
+  if (Size <= 3) {
+    return 0;
+  }
+
+  const auto first = Data[0];
+  Data++;
+  Size--;
+
+  try {
+    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_time(Data, Size);
+      break;
+    default:
+      break;
+    }
+  } catch (std::exception& /*e*/) {
+  }
+  return 0;
+}

test/fuzzing/sprintf.cpp

@@ -0,0 +1,116 @@
+// Copyright (c) 2019, Paul Dreik
+// License: see LICENSE.rst in the fmt root directory
+#include <fmt/format.h>
+#include <fmt/printf.h>
+#include <cstdint>
+#include <stdexcept>
+
+#include "fuzzer_common.h"
+
+using fmt_fuzzer::Nfixed;
+
+template <typename Item1, typename Item2>
+void invoke_fmt(const uint8_t* Data, std::size_t Size) {
+  constexpr auto N1 = sizeof(Item1);
+  constexpr auto N2 = sizeof(Item2);
+  static_assert(N1 <= Nfixed, "size1 exceeded");
+  static_assert(N2 <= Nfixed, "size2 exceeded");
+  if (Size <= Nfixed + Nfixed) {
+    return;
+  }
+  Item1 item1 = fmt_fuzzer::assignFromBuf<Item1>(Data);
+  Data += Nfixed;
+  Size -= Nfixed;
+
+  Item2 item2 = fmt_fuzzer::assignFromBuf<Item2>(Data);
+  Data += Nfixed;
+  Size -= Nfixed;
+
+  auto fmtstring = fmt::string_view(fmt_fuzzer::as_chars(Data), Size);
+
+#if FMT_FUZZ_FORMAT_TO_STRING
+  std::string message = fmt::format(fmtstring, item1, item2);
+#else
+  fmt::memory_buffer message;
+  fmt::format_to(message, fmtstring, 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, std::size_t Size) {
+  if (Size <= 3) {
+    return 0;
+  }
+
+  // switch types depending on the first byte of the input
+  const auto first = Data[0] & 0x0F;
+  const auto second = (Data[0] & 0xF0) >> 4;
+  Data++;
+  Size--;
+
+  auto outer = [=](auto param1) {
+    auto inner = [=](auto param2) {
+      invoke_fmt<decltype(param1), decltype(param2)>(Data, Size);
+    };
+    invoke(second, inner);
+  };
+
+  try {
+    invoke(first, outer);
+  } catch (std::exception& /*e*/) {
+  }
+  return 0;
+}

test/fuzzing/two_args.cpp

@@ -0,0 +1,112 @@
+// Copyright (c) 2019, Paul Dreik
+// License: see LICENSE.rst in the fmt root directory
+#include <fmt/format.h>
+#include <cstdint>
+#include <stdexcept>
+#include <type_traits>
+
+#include "fuzzer_common.h"
+
+constexpr auto Nfixed = fmt_fuzzer::Nfixed;
+
+template <typename Item1, typename Item2>
+void invoke_fmt(const uint8_t* Data, std::size_t Size) {
+  constexpr auto N1 = sizeof(Item1);
+  constexpr auto N2 = sizeof(Item2);
+  static_assert(N1 <= Nfixed, "size1 exceeded");
+  static_assert(N2 <= Nfixed, "size2 exceeded");
+  if (Size <= Nfixed + Nfixed) {
+    return;
+  }
+  const Item1 item1 = fmt_fuzzer::assignFromBuf<Item1>(Data);
+  Data += Nfixed;
+  Size -= Nfixed;
+
+  const Item2 item2 = fmt_fuzzer::assignFromBuf<Item2>(Data);
+  Data += Nfixed;
+  Size -= Nfixed;
+
+  auto fmtstring = fmt::string_view(fmt_fuzzer::as_chars(Data), Size);
+
+#if FMT_FUZZ_FORMAT_TO_STRING
+  std::string message = fmt::format(fmtstring, item1, item2);
+#else
+  fmt::memory_buffer message;
+  fmt::format_to(message, fmtstring, 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;
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* Data, std::size_t Size) {
+  if (Size <= 3) {
+    return 0;
+  }
+
+  // switch types depending on the first byte of the input
+  const auto first = Data[0] & 0x0F;
+  const auto second = (Data[0] & 0xF0) >> 4;
+  Data++;
+  Size--;
+
+  auto outer = [=](auto param1) {
+    auto inner = [=](auto param2) {
+      invoke_fmt<decltype(param1), decltype(param2)>(Data, Size);
+    };
+    invoke(second, inner);
+  };
+
+  try {
+    invoke(first, outer);
+  } catch (std::exception& /*e*/) {
+  }
+  return 0;
+}

test/grisu-test.cc

@@ -0,0 +1,57 @@
+// Formatting library for C++ - Grisu tests
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include "fmt/format.h"
+#include "gtest.h"
+
+static bool reported_skipped;
+
+#undef TEST
+#define TEST(test_fixture, test_name)        \
+  void test_fixture##test_name();            \
+  GTEST_TEST(test_fixture, test_name) {      \
+    if (FMT_USE_GRISU) {                     \
+      test_fixture##test_name();             \
+    } else if (!reported_skipped) {          \
+      reported_skipped = true;               \
+      fmt::print("Skipping Grisu tests.\n"); \
+    }                                        \
+  }                                          \
+  void test_fixture##test_name()
+
+TEST(GrisuTest, NaN) {
+  auto nan = std::numeric_limits<double>::quiet_NaN();
+  EXPECT_EQ("nan", fmt::format("{}", nan));
+  EXPECT_EQ("-nan", fmt::format("{}", -nan));
+}
+
+TEST(GrisuTest, Inf) {
+  auto inf = std::numeric_limits<double>::infinity();
+  EXPECT_EQ("inf", fmt::format("{}", inf));
+  EXPECT_EQ("-inf", fmt::format("{}", -inf));
+}
+
+TEST(GrisuTest, Zero) { EXPECT_EQ("0.0", fmt::format("{}", 0.0)); }
+
+TEST(GrisuTest, Round) {
+  EXPECT_EQ("1.9156918820264798e-56",
+            fmt::format("{}", 1.9156918820264798e-56));
+  EXPECT_EQ("0.0000", fmt::format("{:.4f}", 7.2809479766055470e-15));
+}
+
+TEST(GrisuTest, Prettify) {
+  EXPECT_EQ("0.0001", fmt::format("{}", 1e-4));
+  EXPECT_EQ("1e-05", fmt::format("{}", 1e-5));
+  EXPECT_EQ("9.999e-05", fmt::format("{}", 9.999e-5));
+  EXPECT_EQ("10000000000.0", fmt::format("{}", 1e10));
+  EXPECT_EQ("1e+11", fmt::format("{}", 1e11));
+  EXPECT_EQ("12340000000.0", fmt::format("{}", 1234e7));
+  EXPECT_EQ("12.34", fmt::format("{}", 1234e-2));
+  EXPECT_EQ("0.001234", fmt::format("{}", 1234e-6));
+}
+
+TEST(GrisuTest, ZeroPrecision) { EXPECT_EQ("1", fmt::format("{:.0}", 1.0)); }

test/gtest-extra-test.cc

@@ -7,23 +7,22 @@
 
 #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 +52,9 @@ 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 +69,50 @@ 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_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_WRITE(stdout, std::printf("test"), 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_);
 
@@ -121,33 +125,40 @@ 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_);
 }
@@ -155,18 +166,23 @@ TEST_F(SingleEvaluationTest, SystemErrorTests) {
 // 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_);
 }
@@ -179,8 +195,8 @@ 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 +206,9 @@ 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) {
@@ -268,10 +285,9 @@ 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");
+  EXPECT_NONFATAL_FAILURE(EXPECT_WRITE(stdout, std::printf("that"), "this"),
+                          "Expected: this\n"
+                          "  Actual: that");
 }
 
 TEST(StreamingAssertionsTest, EXPECT_THROW_MSG) {
@@ -279,7 +295,8 @@ TEST(StreamingAssertionsTest, EXPECT_THROW_MSG) {
       << "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 +304,15 @@ TEST(StreamingAssertionsTest, EXPECT_SYSTEM_ERROR) {
       << "unexpected failure";
   EXPECT_NONFATAL_FAILURE(
       EXPECT_SYSTEM_ERROR(throw_system_error(), EDOM, "other")
-      << "expected failure", "expected failure");
+          << "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");
+  EXPECT_WRITE(stdout, std::printf("test"), "test") << "unexpected failure";
+  EXPECT_NONFATAL_FAILURE(EXPECT_WRITE(stdout, std::printf("test"), "other")
+                              << "expected failure",
+                          "expected failure");
 }
 
 TEST(UtilTest, FormatSystemError) {
@@ -311,8 +328,8 @@ using fmt::error_code;
 using fmt::file;
 
 TEST(ErrorCodeTest, Ctor) {
-  EXPECT_EQ(0, error_code().get());
-  EXPECT_EQ(42, error_code(42).get());
+  EXPECT_EQ(error_code().get(), 0);
+  EXPECT_EQ(error_code(42).get(), 42);
 }
 
 TEST(OutputRedirectTest, ScopedRedirect) {
@@ -340,9 +357,9 @@ 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{nullptr};
-  EXPECT_SYSTEM_ERROR_NOASSERT(redir.reset(new OutputRedirect(f.get())),
-      EBADF, "cannot flush stream");
+  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 +369,10 @@ TEST(OutputRedirectTest, DupErrorInCtor) {
   int fd = (f.fileno)();
   file copy = file::dup(fd);
   FMT_POSIX(close(fd));
-  scoped_ptr<OutputRedirect> redir{nullptr};
-  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 +401,8 @@ 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 +412,20 @@ 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(nullptr));
-  }, 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

@@ -12,25 +12,23 @@
 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);
   }
 }
@@ -56,8 +54,7 @@ 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;
@@ -69,7 +66,7 @@ std::string OutputRedirect::restore_and_read() {
   return content;
 }
 
-std::string read(file &f, std::size_t count) {
+std::string read(file& f, std::size_t count) {
   std::string buffer(count, '\0');
   std::size_t n = 0, offset = 0;
   do {

test/gtest-extra.h

@@ -14,58 +14,56 @@
 #include "fmt/core.h"
 
 #ifndef FMT_USE_FILE_DESCRIPTORS
-# define FMT_USE_FILE_DESCRIPTORS 0
+#  define FMT_USE_FILE_DESCRIPTORS 0
 #endif
 
 #if FMT_USE_FILE_DESCRIPTORS
-# include "fmt/posix.h"
+#  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
 
@@ -73,7 +71,7 @@ std::string format_system_error(int error_code, fmt::string_view message);
 // 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 +81,7 @@ 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 +89,28 @@ 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.
@@ -122,38 +119,41 @@ 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, std::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, std::strlen(expected_content)))
 
 #endif  // FMT_USE_FILE_DESCRIPTORS
 
-template <typename Mock>
-struct ScopedMock : testing::StrictMock<Mock> {
+template <typename Mock> struct ScopedMock : testing::StrictMock<Mock> {
   ScopedMock() { Mock::instance = this; }
   ~ScopedMock() { Mock::instance = nullptr; }
 };

test/locale-test.cc

@@ -0,0 +1,52 @@
+// Formatting library for C++ - locale tests
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include "fmt/locale.h"
+#include "gmock.h"
+
+#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
+template <typename Char> struct numpunct : std::numpunct<Char> {
+ protected:
+  Char do_decimal_point() const FMT_OVERRIDE { return '?'; }
+  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, "{:n}", 1.23));
+  // Test with Grisu disabled.
+  fmt::memory_buffer buf;
+  fmt::internal::writer w(buf, fmt::internal::locale_ref(loc));
+  auto specs = fmt::format_specs();
+  specs.type = 'n';
+  w.write_double<double, false>(1.23, specs);
+  EXPECT_EQ(fmt::to_string(buf), "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));
+  fmt::format_arg_store<fmt::format_context, int> as{1234567};
+  EXPECT_EQ("1~234~567", fmt::vformat(loc, "{:n}", fmt::format_args(as)));
+  std::string s;
+  fmt::format_to(std::back_inserter(s), loc, "{:n}", 1234567);
+  EXPECT_EQ("1~234~567", s);
+}
+
+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));
+  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)));
+  auto sep =
+      std::use_facet<std::numpunct<wchar_t>>(std::locale("C")).thousands_sep();
+  auto result = sep == ',' ? L"1,234,567" : L"1234567";
+  EXPECT_EQ(result, fmt::format(std::locale("C"), L"{:n}", 1234567));
+}
+#endif  // FMT_STATIC_THOUSANDS_SEPARATOR

test/mock-allocator.h

@@ -8,58 +8,51 @@
 #ifndef FMT_MOCK_ALLOCATOR_H_
 #define FMT_MOCK_ALLOCATOR_H_
 
+#include "fmt/format.h"
 #include "gmock.h"
 
-template <typename T>
-class MockAllocator {
+template <typename T> class mock_allocator {
  public:
-  MockAllocator() {}
-  MockAllocator(const MockAllocator &) {}
+  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*(std::size_t n));
+  MOCK_METHOD2_T(deallocate, void(T* p, std::size_t n));
 };
 
-template <typename Allocator>
-class AllocatorRef {
+template <typename Allocator> class allocator_ref {
  private:
-  Allocator *alloc_;
+  Allocator* alloc_;
 
- public:
-  typedef typename Allocator::value_type value_type;
-
-  explicit AllocatorRef(Allocator *alloc = nullptr) : alloc_(alloc) {}
-
-  AllocatorRef(const AllocatorRef &other) : alloc_(other.alloc_) {}
-
-  AllocatorRef& operator=(const AllocatorRef &other) {
-    alloc_ = other.alloc_;
-    return *this;
-  }
-
-#if FMT_USE_RVALUE_REFERENCES
- private:
-  void move(AllocatorRef &other) {
+  void move(allocator_ref& other) {
     alloc_ = other.alloc_;
     other.alloc_ = nullptr;
   }
 
  public:
-  AllocatorRef(AllocatorRef &&other) {
-    move(other);
-  }
+  typedef typename Allocator::value_type value_type;
 
-  AllocatorRef& operator=(AllocatorRef &&other) {
+  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& operator=(allocator_ref&& other) {
     assert(this != &other);
     move(other);
     return *this;
   }
-#endif
 
-  Allocator *get() const { return alloc_; }
+  allocator_ref& operator=(const allocator_ref& other) {
+    alloc_ = other.alloc_;
+    return *this;
+  }
+
+ public:
+  Allocator* get() const { return alloc_; }
 
   value_type* allocate(std::size_t n) {
-    return fmt::internal::allocate(*alloc_, n);
+    return std::allocator_traits<Allocator>::allocate(*alloc_, n);
   }
   void deallocate(value_type* p, std::size_t n) { alloc_->deallocate(p, n); }
 };

test/ostream-test.cc

@@ -5,6 +5,22 @@
 //
 // For the license information refer to format.h.
 
+#define FMT_STRING_ALIAS 1
+#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 "fmt/ostream.h"
 
 #include <sstream>
@@ -15,51 +31,56 @@
 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::internal::convert_to_int<TestEnum, char>::value));
-  EXPECT_EQ("TestEnum", fmt::format("{}", TestEnum()));
-  EXPECT_EQ("0", fmt::format("{}", A));
-  EXPECT_FALSE((fmt::internal::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;
+using range = fmt::buffer_range<char>;
 
-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::arg_formatter<range> {
+  fmt::format_parse_context parse_ctx;
+  test_arg_formatter(fmt::format_context& ctx, fmt::format_specs& s)
+      : fmt::arg_formatter<range>(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::internal::buffer<char>& base = buffer;
+  fmt::format_context ctx(std::back_inserter(base), 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::internal::make_arg<fmt::format_context>(streamable_enum()));
+  EXPECT_EQ("streamable_enum", std::string(buffer.data(), buffer.size()));
 }
 
 TEST(OStreamTest, Format) {
@@ -74,20 +95,22 @@ 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_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")));
@@ -95,7 +118,7 @@ TEST(OStreamTest, FormatSpecs) {
 }
 
 struct EmptyTest {};
-static std::ostream &operator<<(std::ostream &os, EmptyTest) {
+static std::ostream& operator<<(std::ostream& os, EmptyTest) {
   return os << "";
 }
 
@@ -115,42 +138,40 @@ 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);
   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;
+  std::size_t max_size = fmt::internal::max_value<std::size_t>();
+  std::streamsize max_streamsize = fmt::internal::max_value<std::streamsize>();
+  if (max_size <= fmt::internal::to_unsigned(max_streamsize)) return;
 
-  struct test_buffer : fmt::internal::buffer {
+  struct test_buffer : fmt::internal::buffer<char> {
     explicit test_buffer(std::size_t size) { resize(size); }
     void grow(std::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 = nullptr;
-  std::size_t size = max_size;
+  const char* data = nullptr;
+  typedef std::make_unsigned<std::streamsize>::type ustreamsize;
+  ustreamsize size = max_size;
   do {
-    typedef std::make_unsigned<std::streamsize>::type ustreamsize;
-    ustreamsize n = std::min<ustreamsize>(
-          size, fmt::internal::to_unsigned(max_streamsize));
+    auto n = std::min(size, fmt::internal::to_unsigned(max_streamsize));
     EXPECT_CALL(streambuf, xsputn(data, static_cast<std::streamsize>(n)))
         .WillOnce(testing::Return(max_streamsize));
     data += n;
@@ -167,5 +188,70 @@ TEST(OStreamTest, Join) {
 #if FMT_USE_CONSTEXPR
 TEST(OStreamTest, ConstexprString) {
   EXPECT_EQ("42", format(fmt("{}"), std::string("42")));
+  EXPECT_EQ("a string", format(fmt("{0}"), TestString("a string")));
 }
 #endif
+
+namespace fmt_test {
+struct ABC {};
+
+template <typename Output> Output& operator<<(Output& out, ABC) {
+  out << "ABC";
+  return out;
+}
+}  // 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];
+  buffer[3] = 'x';
+  auto result = fmt::format_to_n(buffer, 3, "{}", fmt_test::ABC());
+  EXPECT_EQ(3u, result.size);
+  EXPECT_EQ(buffer + 3, result.out);
+  EXPECT_EQ("ABCx", fmt::string_view(buffer, 4));
+  result = fmt::format_to_n(buffer, 3, "x{}y", fmt_test::ABC());
+  EXPECT_EQ(5u, result.size);
+  EXPECT_EQ(buffer + 3, result.out);
+  EXPECT_EQ("xABx", fmt::string_view(buffer, 4));
+}
+#endif
+
+#if FMT_USE_USER_DEFINED_LITERALS
+TEST(FormatTest, UDL) {
+  using namespace fmt::literals;
+  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")));
+}

test/posix-mock-test.cc

@@ -6,8 +6,8 @@
 // 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"
@@ -16,11 +16,12 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <climits>
+#include <memory>
 
 #ifdef _WIN32
-# include <io.h>
-# undef max
-# undef ERROR
+#  include <io.h>
+#  undef max
+#  undef ERROR
 #endif
 
 #include "gmock.h"
@@ -31,10 +32,9 @@ 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;
@@ -53,24 +53,24 @@ std::size_t write_nbyte;
 bool sysconf_error;
 
 enum FStatSimulation { 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 +80,7 @@ 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 +88,9 @@ 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 +130,18 @@ int test::dup2(int fildes, int fildes2) {
   return ::FMT_POSIX(dup2(fildes, fildes2));
 }
 
-FILE *test::fdopen(int fildes, const char *mode) {
+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 +153,23 @@ 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) {
+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 +179,18 @@ 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) {
@@ -208,17 +206,17 @@ TEST(UtilTest, GetPageSize) {
 #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
 }
 
 TEST(FileTest, OpenRetry) {
   write_file("test", "there must be something here");
-  scoped_ptr<file> f{nullptr};
-  EXPECT_RETRY(f.reset(new file("test", file::RDONLY)),
-               open, "cannot open file test");
+  std::unique_ptr<file> f{nullptr};
+  EXPECT_RETRY(f.reset(new file("test", file::RDONLY)), open,
+               "cannot open file test");
 #ifndef _WIN32
   char c = 0;
   f->read(&c, 1);
@@ -228,14 +226,16 @@ TEST(FileTest, OpenRetry) {
 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(nullptr);
-    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);
 }
 
@@ -256,8 +256,8 @@ TEST(FileTest, Size) {
   EXPECT_EQ(content.size(), static_cast<unsigned long long>(f.size()));
 #ifdef _WIN32
   fmt::memory_buffer message;
-  fmt::internal::format_windows_error(
-      message, ERROR_ACCESS_DENIED, "cannot get file size");
+  fmt::internal::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;
@@ -284,8 +284,8 @@ TEST(FileTest, ReadRetry) {
   write_end.close();
   char buffer[SIZE];
   std::size_t count = 0;
-  EXPECT_RETRY(count = read_end.read(buffer, SIZE),
-      read, "cannot read from file");
+  EXPECT_RETRY(count = read_end.read(buffer, SIZE), read,
+               "cannot read from file");
   EXPECT_EQ_POSIX(static_cast<std::streamsize>(SIZE), count);
 }
 
@@ -294,8 +294,8 @@ TEST(FileTest, WriteRetry) {
   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");
+  EXPECT_RETRY(count = write_end.write("test", SIZE), write,
+               "cannot write to file");
   write_end.close();
 #ifndef _WIN32
   EXPECT_EQ(static_cast<std::streamsize>(SIZE), count);
@@ -312,8 +312,7 @@ TEST(FileTest, ConvertReadCount) {
   file::pipe(read_end, write_end);
   char c;
   std::size_t size = UINT_MAX;
-  if (sizeof(unsigned) != sizeof(std::size_t))
-    ++size;
+  if (sizeof(unsigned) != sizeof(std::size_t)) ++size;
   read_count = 1;
   read_nbyte = 0;
   EXPECT_THROW(read_end.read(&c, size), fmt::system_error);
@@ -326,8 +325,7 @@ TEST(FileTest, ConvertWriteCount) {
   file::pipe(read_end, write_end);
   char c;
   std::size_t size = UINT_MAX;
-  if (sizeof(unsigned) != sizeof(std::size_t))
-    ++size;
+  if (sizeof(unsigned) != sizeof(std::size_t)) ++size;
   write_count = 1;
   write_nbyte = 0;
   EXPECT_THROW(write_end.write(&c, size), fmt::system_error);
@@ -339,7 +337,8 @@ TEST(FileTest, ConvertWriteCount) {
 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 +347,8 @@ 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) {
@@ -369,8 +368,8 @@ TEST(FileTest, Dup2NoExceptRetry) {
 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;
 }
 
@@ -378,16 +377,16 @@ 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{nullptr};
-  EXPECT_RETRY(f.reset(new buffered_file("test", "r")),
-               fopen, "cannot open file test");
+  std::unique_ptr<buffered_file> f{nullptr};
+  EXPECT_RETRY(f.reset(new buffered_file("test", "r")), fopen,
+               "cannot open file test");
 #ifndef _WIN32
   char c = 0;
   if (fread(&c, 1, 1, f->get()) < 1)
@@ -398,14 +397,16 @@ TEST(BufferedFileTest, OpenRetry) {
 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(nullptr);
-    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);
 }
 
@@ -430,14 +431,14 @@ TEST(BufferedFileTest, FilenoNoRetry) {
 }
 
 struct TestMock {
-  static TestMock *instance;
-} *TestMock::instance;
+  static TestMock* instance;
+} * TestMock::instance;
 
 TEST(ScopedMock, Scope) {
   {
     ScopedMock<TestMock> mock;
     EXPECT_EQ(&mock, TestMock::instance);
-    TestMock &copy = mock;
+    TestMock& copy = mock;
     static_cast<void>(copy);
   }
   EXPECT_EQ(nullptr, TestMock::instance);
@@ -445,23 +446,27 @@ TEST(ScopedMock, Scope) {
 
 #ifdef FMT_LOCALE
 
-typedef fmt::Locale::Type LocaleType;
+typedef fmt::Locale::type LocaleType;
 
 struct LocaleMock {
-  static LocaleMock *instance;
-  MOCK_METHOD3(newlocale, LocaleType (int category_mask, const char *locale,
-                                      LocaleType base));
-  MOCK_METHOD1(freelocale, void (LocaleType locale));
+  static LocaleMock* instance;
+  MOCK_METHOD3(newlocale, LocaleType(int category_mask, const char* locale,
+                                     LocaleType base));
+  MOCK_METHOD1(freelocale, void(LocaleType 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, LocaleType locale));
+} * LocaleMock::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) {
+_locale_t _create_locale(int category, const char* locale) {
   return LocaleMock::instance->newlocale(category, locale, 0);
 }
 
@@ -469,38 +474,44 @@ void _free_locale(_locale_t locale) {
   LocaleMock::instance->freelocale(locale);
 }
 
-double _strtod_l(const char *nptr, char **endptr, _locale_t locale) {
+double _strtod_l(const char* nptr, char** endptr, _locale_t locale) {
   return LocaleMock::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 {
+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);
   return FreeLocaleResult();
 }
 
-double strtod_l(const char *nptr, char **endptr, LocaleType locale) FMT_LOCALE_THROW {
+double strtod_l(const char* nptr, char** endptr,
+                LocaleType locale) FMT_LOCALE_THROW {
   return LocaleMock::instance->strtod_l(nptr, endptr, locale);
 }
 
-#undef FMT_LOCALE_THROW
+#  undef FMT_LOCALE_THROW
 
 TEST(LocaleTest, LocaleMock) {
   ScopedMock<LocaleMock> mock;
@@ -510,9 +521,9 @@ TEST(LocaleTest, LocaleMock) {
 }
 
 TEST(LocaleTest, Locale) {
-#ifndef LC_NUMERIC_MASK
+#  ifndef LC_NUMERIC_MASK
   enum { LC_NUMERIC_MASK = LC_NUMERIC };
-#endif
+#  endif
   ScopedMock<LocaleMock> mock;
   LocaleType impl = reinterpret_cast<LocaleType>(42);
   EXPECT_CALL(mock, newlocale(LC_NUMERIC_MASK, StrEq("C"), nullptr))
@@ -528,7 +539,7 @@ TEST(LocaleTest, Strtod) {
       .WillOnce(Return(reinterpret_cast<LocaleType>(42)));
   EXPECT_CALL(mock, freelocale(_));
   fmt::Locale locale;
-  const char *str = "4.2";
+  const char* str = "4.2";
   char end = 'x';
   EXPECT_CALL(mock, strtod_l(str, _, locale.get()))
       .WillOnce(testing::DoAll(testing::SetArgPointee<1>(&end), Return(777)));

test/posix-mock.h

@@ -12,10 +12,10 @@
 #include <stdio.h>
 
 #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 +28,13 @@ 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 +48,20 @@ 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);
 }  // namespace test
 
 #define FMT_SYSTEM(call) test::call

test/posix-test.cc

@@ -7,21 +7,20 @@
 
 #include <cstdlib>  // std::exit
 #include <cstring>
+#include <memory>
 
 #include "fmt/posix.h"
 #include "gtest-extra.h"
 #include "util.h"
 
 #ifdef fileno
-# undef 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;
@@ -45,9 +44,9 @@ static file open_file() {
 }
 
 // Attempts to write a string to a file.
-static void write(file &f, fmt::string_view s) {
+static void write(file& f, fmt::string_view s) {
   std::size_t num_chars_left = s.size();
-  const char *ptr = s.data();
+  const char* ptr = s.data();
   do {
     std::size_t count = f.write(ptr, num_chars_left);
     ptr += count;
@@ -64,7 +63,7 @@ TEST(BufferedFileTest, DefaultCtor) {
 
 TEST(BufferedFileTest, MoveCtor) {
   buffered_file bf = open_buffered_file();
-  FILE *fp = bf.get();
+  FILE* fp = bf.get();
   EXPECT_TRUE(fp != nullptr);
   buffered_file bf2(std::move(bf));
   EXPECT_EQ(fp, bf2.get());
@@ -73,7 +72,7 @@ TEST(BufferedFileTest, MoveCtor) {
 
 TEST(BufferedFileTest, MoveAssignment) {
   buffered_file bf = open_buffered_file();
-  FILE *fp = bf.get();
+  FILE* fp = bf.get();
   EXPECT_TRUE(fp != nullptr);
   buffered_file bf2;
   bf2 = std::move(bf);
@@ -90,13 +89,13 @@ TEST(BufferedFileTest, MoveAssignmentClosesFile) {
 }
 
 TEST(BufferedFileTest, MoveFromTemporaryInCtor) {
-  FILE *fp = nullptr;
+  FILE* fp = nullptr;
   buffered_file f(open_buffered_file(&fp));
   EXPECT_EQ(fp, f.get());
 }
 
 TEST(BufferedFileTest, MoveFromTemporaryInAssignment) {
-  FILE *fp = nullptr;
+  FILE* fp = nullptr;
   buffered_file f;
   f = open_buffered_file(&fp);
   EXPECT_EQ(fp, f.get());
@@ -119,15 +118,17 @@ TEST(BufferedFileTest, CloseFileInDtor) {
 }
 
 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(nullptr));
-  }, format_system_error(EBADF, "cannot close file") + "\n");
+  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) {
@@ -150,13 +151,15 @@ TEST(BufferedFileTest, Fileno) {
 #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);
-    }
-  }, "");
+  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);
@@ -170,7 +173,7 @@ TEST(FileTest, DefaultCtor) {
 }
 
 TEST(FileTest, OpenBufferedFileInCtor) {
-  FILE *fp = safe_fopen("test-file", "w");
+  FILE* fp = safe_fopen("test-file", "w");
   std::fputs(FILE_CONTENT, fp);
   std::fclose(fp);
   file f("test-file", file::RDONLY);
@@ -178,8 +181,8 @@ TEST(FileTest, OpenBufferedFileInCtor) {
 }
 
 TEST(FileTest, OpenBufferedFileError) {
-  EXPECT_SYSTEM_ERROR(file("nonexistent", file::RDONLY),
-      ENOENT, "cannot open file nonexistent");
+  EXPECT_SYSTEM_ERROR(file("nonexistent", file::RDONLY), ENOENT,
+                      "cannot open file nonexistent");
 }
 
 TEST(FileTest, MoveCtor) {
@@ -209,7 +212,7 @@ TEST(FileTest, MoveAssignmentClosesFile) {
   EXPECT_TRUE(isclosed(old_fd));
 }
 
-static file OpenBufferedFile(int &fd) {
+static file OpenBufferedFile(int& fd) {
   file f = open_file();
   fd = f.descriptor();
   return f;
@@ -246,15 +249,17 @@ TEST(FileTest, CloseFileInDtor) {
 }
 
 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(nullptr));
-  }, format_system_error(EBADF, "cannot close file") + "\n");
+  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) {
@@ -310,8 +315,8 @@ TEST(FileTest, Dup) {
 #ifndef __COVERITY__
 TEST(FileTest, DupError) {
   int value = -1;
-  EXPECT_SYSTEM_ERROR_NOASSERT(file::dup(value),
-      EBADF, "cannot duplicate file descriptor -1");
+  EXPECT_SYSTEM_ERROR_NOASSERT(file::dup(value), EBADF,
+                               "cannot duplicate file descriptor -1");
 }
 #endif
 
@@ -325,8 +330,9 @@ TEST(FileTest, Dup2) {
 
 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()));
+  EXPECT_SYSTEM_ERROR_NOASSERT(
+      f.dup2(-1), EBADF,
+      fmt::format("cannot duplicate file descriptor {} to -1", f.descriptor()));
 }
 
 TEST(FileTest, Dup2NoExcept) {
@@ -334,7 +340,7 @@ TEST(FileTest, Dup2NoExcept) {
   file copy = open_file();
   error_code ec;
   f.dup2(copy.descriptor(), ec);
-  EXPECT_EQ(0, ec.get());
+  EXPECT_EQ(ec.get(), 0);
   EXPECT_NE(f.descriptor(), copy.descriptor());
   EXPECT_READ(copy, FILE_CONTENT);
 }
@@ -362,12 +368,6 @@ TEST(FileTest, Fdopen) {
   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;

test/printf-test.cc

@@ -16,6 +16,7 @@
 
 using fmt::format;
 using fmt::format_error;
+using fmt::internal::max_value;
 
 const unsigned BIG_NUM = INT_MAX + 1u;
 
@@ -32,22 +33,33 @@ static std::wstring make_positional(fmt::wstring_view format) {
   return s;
 }
 
-#define EXPECT_PRINTF(expected_output, format, arg) \
-  EXPECT_EQ(expected_output, fmt::sprintf(format, arg)) \
-    << "format: " << 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) {
+  return fmt::sprintf(format, args...);
+}
+template <typename... Args>
+std::wstring test_sprintf(fmt::wstring_view format, const Args&... args) {
+  return fmt::sprintf(format, args...);
+}
+
+#define EXPECT_PRINTF(expected_output, format, arg)     \
+  EXPECT_EQ(expected_output, test_sprintf(format, arg)) \
+      << "format: " << format;                          \
   EXPECT_EQ(expected_output, fmt::sprintf(make_positional(format), arg))
 
 TEST(PrintfTest, NoArgs) {
-  EXPECT_EQ("test", fmt::sprintf("test"));
+  EXPECT_EQ("test", test_sprintf("test"));
   EXPECT_EQ(L"test", fmt::sprintf(L"test"));
 }
 
 TEST(PrintfTest, Escape) {
-  EXPECT_EQ("%", fmt::sprintf("%%"));
-  EXPECT_EQ("before %", fmt::sprintf("before %%"));
-  EXPECT_EQ("% after", fmt::sprintf("%% after"));
-  EXPECT_EQ("before % after", fmt::sprintf("before %% after"));
-  EXPECT_EQ("%s", fmt::sprintf("%%s"));
+  EXPECT_EQ("%", test_sprintf("%%"));
+  EXPECT_EQ("before %", test_sprintf("before %%"));
+  EXPECT_EQ("% after", test_sprintf("%% after"));
+  EXPECT_EQ("before % after", test_sprintf("before %% after"));
+  EXPECT_EQ("%s", test_sprintf("%%s"));
   EXPECT_EQ(L"%", fmt::sprintf(L"%%"));
   EXPECT_EQ(L"before %", fmt::sprintf(L"before %%"));
   EXPECT_EQ(L"% after", fmt::sprintf(L"%% after"));
@@ -56,61 +68,60 @@ TEST(PrintfTest, Escape) {
 }
 
 TEST(PrintfTest, PositionalArgs) {
-  EXPECT_EQ("42", fmt::sprintf("%1$d", 42));
-  EXPECT_EQ("before 42", fmt::sprintf("before %1$d", 42));
-  EXPECT_EQ("42 after", fmt::sprintf("%1$d after",42));
-  EXPECT_EQ("before 42 after", fmt::sprintf("before %1$d after", 42));
-  EXPECT_EQ("answer = 42", fmt::sprintf("%1$s = %2$d", "answer", 42));
-  EXPECT_EQ("42 is the answer",
-      fmt::sprintf("%2$d is the %1$s", "answer", 42));
-  EXPECT_EQ("abracadabra", fmt::sprintf("%1$s%2$s%1$s", "abra", "cad"));
+  EXPECT_EQ("42", test_sprintf("%1$d", 42));
+  EXPECT_EQ("before 42", test_sprintf("before %1$d", 42));
+  EXPECT_EQ("42 after", test_sprintf("%1$d after", 42));
+  EXPECT_EQ("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$s", "answer", 42));
+  EXPECT_EQ("abracadabra", test_sprintf("%1$s%2$s%1$s", "abra", "cad"));
 }
 
 TEST(PrintfTest, AutomaticArgIndexing) {
-  EXPECT_EQ("abc", fmt::sprintf("%c%c%c", 'a', 'b', 'c'));
+  EXPECT_EQ("abc", test_sprintf("%c%c%c", 'a', 'b', 'c'));
 }
 
 TEST(PrintfTest, NumberIsTooBigInArgIndex) {
-  EXPECT_THROW_MSG(fmt::sprintf(format("%{}$", BIG_NUM)),
-      format_error, "number is too big");
-  EXPECT_THROW_MSG(fmt::sprintf(format("%{}$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(fmt::sprintf("%1$d%", 1, 2),
-      format_error, "cannot switch from manual to automatic argument indexing");
-  EXPECT_THROW_MSG(fmt::sprintf(format("%1$d%{}d", BIG_NUM), 1, 2),
-      format_error, "number is too big");
-  EXPECT_THROW_MSG(fmt::sprintf("%1$d%d", 1, 2),
-      format_error, "cannot switch from manual to automatic argument indexing");
+  EXPECT_THROW_MSG(test_sprintf("%1$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");
 
-  EXPECT_THROW_MSG(fmt::sprintf("%d%1$", 1, 2),
-      format_error, "cannot switch from automatic to manual argument indexing");
-  EXPECT_THROW_MSG(fmt::sprintf(format("%d%{}$d", BIG_NUM), 1, 2),
-      format_error, "number is too big");
-  EXPECT_THROW_MSG(fmt::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(fmt::sprintf(format("%d%1${}d", BIG_NUM), 1, 2),
-      format_error, "number is too big");
-  EXPECT_THROW_MSG(fmt::sprintf(format("%1$d%{}d", BIG_NUM), 1, 2),
-      format_error, "number is too big");
+  EXPECT_THROW_MSG(test_sprintf(format("%d%1${}d", BIG_NUM), 1, 2),
+                   format_error, "number is too big");
+  EXPECT_THROW_MSG(test_sprintf(format("%1$d%{}d", BIG_NUM), 1, 2),
+                   format_error, "number is too big");
 }
 
 TEST(PrintfTest, InvalidArgIndex) {
-  EXPECT_THROW_MSG(fmt::sprintf("%0$d", 42), format_error,
-      "argument index out of range");
-  EXPECT_THROW_MSG(fmt::sprintf("%2$d", 42), format_error,
-      "argument index out of range");
-  EXPECT_THROW_MSG(fmt::sprintf(format("%{}$d", INT_MAX), 42),
-      format_error, "argument index out of range");
+  EXPECT_THROW_MSG(test_sprintf("%0$d", 42), format_error,
+                   "argument index out of range");
+  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");
 
-  EXPECT_THROW_MSG(fmt::sprintf("%2$", 42),
-      format_error, "argument index out of range");
-  EXPECT_THROW_MSG(fmt::sprintf(format("%{}$d", BIG_NUM), 42),
-      format_error, "number is too big");
+  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");
 }
 
 TEST(PrintfTest, DefaultAlignRight) {
@@ -164,8 +175,8 @@ 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);
@@ -196,24 +207,24 @@ TEST(PrintfTest, Width) {
   EXPECT_PRINTF("  abc", "%5s", "abc");
 
   // Width cannot be specified twice.
-  EXPECT_THROW_MSG(fmt::sprintf("%5-5d", 42), format_error,
-      "invalid type specifier");
+  EXPECT_THROW_MSG(test_sprintf("%5-5d", 42), format_error,
+                   "invalid type specifier");
 
-  EXPECT_THROW_MSG(fmt::sprintf(format("%{}d", BIG_NUM), 42),
-      format_error, "number is too big");
-  EXPECT_THROW_MSG(fmt::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", fmt::sprintf("%*d", 5, 42));
-  EXPECT_EQ("42   ", fmt::sprintf("%*d", -5, 42));
-  EXPECT_THROW_MSG(fmt::sprintf("%*d", 5.0, 42), format_error,
-      "width is not integer");
-  EXPECT_THROW_MSG(fmt::sprintf("%*d"), format_error,
-      "argument index out of range");
-  EXPECT_THROW_MSG(fmt::sprintf("%*d", BIG_NUM, 42), format_error,
-      "number is too big");
+  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");
+  EXPECT_THROW_MSG(test_sprintf("%*d", BIG_NUM, 42), format_error,
+                   "number is too big");
 }
 
 TEST(PrintfTest, IntPrecision) {
@@ -242,8 +253,7 @@ 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);
 }
@@ -253,27 +263,25 @@ TEST(PrintfTest, IgnorePrecisionForNonNumericArg) {
 }
 
 TEST(PrintfTest, DynamicPrecision) {
-  EXPECT_EQ("00042", fmt::sprintf("%.*d", 5, 42));
-  EXPECT_EQ("42", fmt::sprintf("%.*d", -5, 42));
-  EXPECT_THROW_MSG(fmt::sprintf("%.*d", 5.0, 42), format_error,
-      "precision is not integer");
-  EXPECT_THROW_MSG(fmt::sprintf("%.*d"), format_error,
-      "argument index out of range");
-  EXPECT_THROW_MSG(fmt::sprintf("%.*d", BIG_NUM, 42), format_error,
-      "number is too big");
+  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");
+  EXPECT_THROW_MSG(test_sprintf("%.*d", BIG_NUM, 42), format_error,
+                   "number is too big");
   if (sizeof(long long) != sizeof(int)) {
     long long prec = static_cast<long long>(INT_MIN) - 1;
-    EXPECT_THROW_MSG(fmt::sprintf("%.*d", prec, 42), format_error,
-        "number is too big");
- }
+    EXPECT_THROW_MSG(test_sprintf("%.*d", prec, 42), format_error,
+                     "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);
@@ -284,17 +292,16 @@ 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();
+  unsigned long long max = max_value<U>();
   using fmt::internal::const_check;
-  if (const_check(max <= static_cast<unsigned>(numeric_limits<int>::max()))) {
+  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())) {
+  } else if (const_check(max <= max_value<unsigned>())) {
     signed_value = static_cast<unsigned>(value);
     unsigned_value = static_cast<unsigned>(value);
   }
@@ -324,27 +331,26 @@ 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();
+  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) {
@@ -360,9 +366,9 @@ TEST(PrintfTest, Length) {
   TestLength<intmax_t>("j");
   TestLength<std::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) {
@@ -383,7 +389,7 @@ 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);
 }
 
@@ -400,6 +406,8 @@ 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);
   safe_sprintf(buffer, "%a", -392.65);
   EXPECT_EQ(buffer, format("{:a}", -392.65));
   safe_sprintf(buffer, "%A", -392.65);
@@ -417,34 +425,34 @@ 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 = nullptr;
+  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 = nullptr;
+  const wchar_t* null_wstr = nullptr;
   EXPECT_PRINTF(L"(null)", L"%s", null_wstr);
   EXPECT_PRINTF(L"    (null)", L"%10s", null_wstr);
 }
 
 TEST(PrintfTest, Pointer) {
   int n;
-  void *p = &n;
+  void* p = &n;
   EXPECT_PRINTF(fmt::format("{}", p), "%p", p);
   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 = nullptr;
+  const char* null_str = nullptr;
   EXPECT_PRINTF("(nil)", "%p", null_str);
 
   p = &n;
@@ -452,9 +460,9 @@ TEST(PrintfTest, Pointer) {
   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 = nullptr;
+  const wchar_t* null_wstr = nullptr;
   EXPECT_PRINTF(L"(nil)", L"%p", null_wstr);
 }
 
@@ -464,14 +472,12 @@ TEST(PrintfTest, Location) {
 
 enum E { A = 42 };
 
-TEST(PrintfTest, Enum) {
-  EXPECT_PRINTF("42", "%d", A);
-}
+TEST(PrintfTest, Enum) { EXPECT_PRINTF("42", "%d", A); }
 
 #if FMT_USE_FILE_DESCRIPTORS
 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");
@@ -485,12 +491,10 @@ 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", fmt::sprintf("%s", TestString("abc")));
+  EXPECT_EQ("abc", test_sprintf("%s", TestString("abc")));
 }
 
 TEST(PrintfTest, OStream) {
@@ -499,3 +503,109 @@ TEST(PrintfTest, OStream) {
   EXPECT_EQ("Don't panic!", os.str());
   EXPECT_EQ(12, ret);
 }
+
+TEST(PrintfTest, VPrintf) {
+  fmt::format_arg_store<fmt::printf_context, int> as{42};
+  fmt::basic_format_args<fmt::printf_context> args(as);
+  EXPECT_EQ(fmt::vsprintf("%d", args), "42");
+  EXPECT_WRITE(stdout, fmt::vprintf("%d", args), "42");
+  EXPECT_WRITE(stdout, fmt::vfprintf(stdout, "%d", args), "42");
+  EXPECT_WRITE(stdout, fmt::vfprintf(std::cout, "%d", args), "42");
+}
+
+template <typename... Args>
+void check_format_string_regression(fmt::string_view s, const Args&... args) {
+  fmt::sprintf(s, args...);
+}
+
+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::basic_format_args<fmt::printf_context> args(as);
+  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")}));
+#endif
+}
+
+TEST(PrintfTest, VSPrintfMakeWArgsExample) {
+  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");
+  fmt::basic_format_args<fmt::wprintf_context> args2(as2);
+  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")}));
+#endif
+}
+
+typedef fmt::printf_arg_formatter<fmt::buffer_range<char>> formatter_t;
+typedef fmt::basic_printf_context<formatter_t::iterator, char> context_t;
+
+// A custom printf argument formatter that doesn't print `-` for floating-point
+// values rounded to 0.
+class custom_printf_arg_formatter : public formatter_t {
+ public:
+  using formatter_t::iterator;
+
+  custom_printf_arg_formatter(formatter_t::iterator iter,
+                              formatter_t::format_specs& specs, context_t& ctx)
+      : formatter_t(iter, specs, ctx) {}
+
+  using formatter_t::operator();
+
+#if FMT_MSC_VER > 0 && FMT_MSC_VER <= 1804
+  template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
+  iterator operator()(T value){
+#else
+  iterator operator()(double value) {
+#endif
+      // Comparing a float to 0.0 is safe.
+      if (round(value * pow(10, specs()->precision)) == 0.0) value = 0;
+  return formatter_t::operator()(value);
+}
+}
+;
+
+typedef fmt::basic_format_args<context_t> format_args_t;
+
+std::string custom_vformat(fmt::string_view format_str, format_args_t args) {
+  fmt::memory_buffer buffer;
+  fmt::vprintf<custom_printf_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_printf_args(args...);
+  return custom_vformat(format_str, {va});
+}
+
+TEST(PrintfTest, CustomFormat) {
+  EXPECT_EQ("0.00", custom_format("%.2f", -.00001));
+  EXPECT_EQ("0.00", custom_format("%.2f", .00001));
+  EXPECT_EQ("1.00", custom_format("%.2f", 1.00001));
+  EXPECT_EQ("-1.00", custom_format("%.2f", -1.00001));
+}

test/ranges-test.cc

@@ -10,17 +10,16 @@
 // {fmt} support for ranges, containers and types tuple interface.
 
 #include "fmt/ranges.h"
+#include "gtest.h"
 
-/// Check if  'if constexpr' is supported.
+// Check if  'if constexpr' is supported.
 #if (__cplusplus > 201402L) || \
     (defined(_MSVC_LANG) && _MSVC_LANG > 201402L && _MSC_VER >= 1910)
 
-#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};
@@ -40,21 +39,39 @@ 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> tu1{42, 1.5f, "this is tuple",
+                                                    'i'};
+  EXPECT_EQ("(42, 1.5, \"this is tuple\", 'i')", fmt::format("{}", tu1));
+}
+
+TEST(RangesTest, JoinTuple) {
+  // Value tuple args
+  std::tuple<char, int, float> t1 = std::make_tuple('a', 1, 2.0f);
+  EXPECT_EQ("(a, 1, 2.0)", 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("4.0", fmt::format("{}", fmt::join(t4, "/")));
 }
 
 struct my_struct {
   int32_t i;
   std::string str;  // can throw
-  template <std::size_t N>
-  decltype(auto) get() const noexcept {
+  template <std::size_t N> decltype(auto) get() const noexcept {
     if constexpr (N == 0)
       return i;
     else if constexpr (N == 1)
@@ -62,8 +79,7 @@ struct my_struct {
   }
 };
 
-template <std::size_t N>
-decltype(auto) get(const my_struct& s) noexcept {
+template <std::size_t N> decltype(auto) get(const my_struct& s) noexcept {
   return s.get<N>();
 }
 
@@ -72,8 +88,7 @@ namespace std {
 template <>
 struct tuple_size<my_struct> : std::integral_constant<std::size_t, 2> {};
 
-template <std::size_t N>
-struct tuple_element<N, my_struct> {
+template <std::size_t N> struct tuple_element<N, my_struct> {
   using type = decltype(std::declval<my_struct>().get<N>());
 };
 
@@ -84,5 +99,36 @@ 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

test/scan-test.cc

@@ -0,0 +1,114 @@
+// 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 <time.h>
+#include <climits>
+
+#include "gmock.h"
+#include "gtest-extra.h"
+#include "scan.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(internal::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 +1,235 @@
+// 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 "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(internal::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(internal::to_unsigned(it - begin()));
+  }
+};
+
+namespace internal {
+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 internal
+
+struct scan_args {
+  int size;
+  const internal::scan_arg* data;
+
+  template <size_t N>
+  scan_args(const std::array<internal::scan_arg, N>& store)
+      : size(N), data(store.data()) {
+    static_assert(N < INT_MAX, "too many arguments");
+  }
+};
+
+namespace internal {
+
+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 + (c - '0');
+    }
+    scan_ctx_.advance_to(it);
+    return value;
+  }
+
+  template <typename T = int> T read_int() {
+    T value = 0;
+    auto it = scan_ctx_.begin(), end = scan_ctx_.end();
+    bool negative = it != end && *it == '-';
+    if (negative) ++it;
+    scan_ctx_.advance_to(it);
+    value = read_uint<typename std::make_unsigned<T>::type>();
+    if (negative) value = -value;
+    return 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 = 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);
+  }
+
+  void on_arg_id() { on_arg_id(next_arg_id_++); }
+  void on_arg_id(int id) {
+    if (id >= args_.size) on_error("argument index out of range");
+    arg_ = args_.data[id];
+  }
+  void on_arg_id(string_view) { on_error("invalid format"); }
+
+  void on_replacement_field(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, it - s);
+      scan_ctx_.advance_to(it);
+      break;
+    }
+    default:
+      assert(false);
+    }
+  }
+
+  const char* on_format_specs(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 internal
+
+template <typename... Args>
+std::array<internal::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) {
+  internal::scan_handler h(format_str, input, args);
+  internal::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 +1,156 @@
+#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("{:n}", 1234);  // s3 == "1,234" (depends on the locale)
+  EXPECT_EQ(s0, "42");
+  EXPECT_EQ(s1, "101010 42 52 2a");
+  EXPECT_EQ(s2, "0x2a 0X2A");
+  EXPECT_EQ(s3, "1,234");
+}
+
+#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::internal::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

@@ -5,23 +5,22 @@
 //
 // For the license information refer to format.h.
 
-#ifndef FMT_TEST_ASSERT_H
-#define FMT_TEST_ASSERT_H
+#ifndef FMT_TEST_ASSERT_H_
+#define FMT_TEST_ASSERT_H_
 
 #include <stdexcept>
+#include "gtest.h"
 
-class AssertionFailure : public std::logic_error {
+class assertion_failure : public std::logic_error {
  public:
-  explicit AssertionFailure(const char *message) : std::logic_error(message) {}
+  explicit assertion_failure(const char* message) : std::logic_error(message) {}
 };
 
 #define FMT_ASSERT(condition, message) \
-  if (!(condition)) throw AssertionFailure(message);
-
-#include "gtest-extra.h"
+  if (!(condition)) throw assertion_failure(message);
 
 // Expects an assertion failure.
 #define EXPECT_ASSERT(stmt, message) \
-  EXPECT_THROW_MSG(stmt, AssertionFailure, message)
+  FMT_TEST_THROW_(stmt, assertion_failure, message, GTEST_NONFATAL_FAILURE_)
 
-#endif  // FMT_TEST_ASSERT_H
+#endif  // FMT_TEST_ASSERT_H_

test/test-main.cc

@@ -9,23 +9,23 @@
 #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

@@ -1,59 +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/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(nullptr);
-  fmt::format(s, *std::localtime(&t));
-}
-
-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)));
-}