Bump version

I got warnings from -Wnoexcept, fixed them.

.github/pull_request_template.md

@@ -1,6 +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.
+<!--
+Please read the contribution guidelines before submitting a pull request:
+https://github.com/fmtlib/fmt/blob/master/CONTRIBUTING.md.
+By submitting this pull request, you agree that your contributions are licensed
+under the {fmt} license, and agree to future changes to the licensing.
+-->

.github/workflows/doc.yml

@@ -0,0 +1,24 @@
+name: doc
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    # Use Ubuntu 20.04 because doxygen 1.8.13 from Ubuntu 18.04 is broken.
+    runs-on: ubuntu-20.04
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Create Build Environment
+      run: |
+        sudo apt update
+        sudo apt install doxygen python3-virtualenv
+        sudo npm install -g less clean-css
+        cmake -E make_directory ${{runner.workspace}}/build
+
+    - name: Build
+      working-directory: ${{runner.workspace}}/build
+      env:
+        KEY: ${{secrets.KEY}}
+      run: $GITHUB_WORKSPACE/support/build-docs.py

.github/workflows/linux.yml

@@ -0,0 +1,79 @@
+name: linux
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        cxx: [g++-4.8, g++-10, clang++-9]
+        build_type: [Debug, Release]
+        std: [11]
+        os: [ubuntu-18.04]
+        include:
+          - cxx: g++-4.8
+            install: sudo apt install g++-4.8
+            os: ubuntu-18.04
+          - cxx: g++-8
+            build_type: Debug
+            std: 14
+            install: sudo apt install g++-8
+            os: ubuntu-18.04
+          - cxx: g++-10
+            build_type: Debug
+            std: 17
+            os: ubuntu-18.04
+          - cxx: g++-11
+            build_type: Debug
+            std: 20
+            os: ubuntu-20.04
+            install: sudo apt install g++-11
+          - cxx: clang++-9
+            build_type: Debug
+            fuzz: -DFMT_FUZZ=ON -DFMT_FUZZ_LINKMAIN=ON
+            std: 17
+            os: ubuntu-18.04
+          - cxx: clang++-11
+            build_type: Debug
+            std: 20
+            os: ubuntu-20.04
+          - cxx: clang++-11
+            build_type: Debug
+            std: 20
+            cxxflags: -stdlib=libc++
+            os: ubuntu-20.04
+            install: sudo apt install libc++-11-dev libc++abi-11-dev
+          - shared: -DBUILD_SHARED_LIBS=ON
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Create Build Environment
+      run: |
+        ${{matrix.install}}
+        sudo apt install locales-all
+        cmake -E make_directory ${{runner.workspace}}/build
+
+    - name: Configure
+      working-directory: ${{runner.workspace}}/build
+      env:
+        CXX: ${{matrix.cxx}}
+        CXXFLAGS: ${{matrix.cxxflags}}
+      run: |
+        cmake -DCMAKE_BUILD_TYPE=${{matrix.build_type}} ${{matrix.fuzz}} ${{matrix.shared}} \
+              -DCMAKE_CXX_STANDARD=${{matrix.std}} -DFMT_DOC=OFF \
+              -DCMAKE_CXX_VISIBILITY_PRESET=hidden -DCMAKE_VISIBILITY_INLINES_HIDDEN=ON \
+              -DFMT_PEDANTIC=ON -DFMT_WERROR=ON $GITHUB_WORKSPACE
+
+    - name: Build
+      working-directory: ${{runner.workspace}}/build
+      run: |
+        threads=`nproc`
+        cmake --build . --config ${{matrix.build_type}} --parallel $threads
+
+    - name: Test
+      working-directory: ${{runner.workspace}}/build
+      run: ctest -C ${{matrix.build_type}}
+      env:
+        CTEST_OUTPUT_ON_FAILURE: True

.github/workflows/macos.yml

@@ -0,0 +1,37 @@
+name: macos
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: macos-10.15
+    strategy:
+      matrix:
+        build_type: [Debug, Release]
+        include:
+          - shared: -DBUILD_SHARED_LIBS=ON
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Create Build Environment
+      run: cmake -E make_directory ${{runner.workspace}}/build
+
+    - name: Configure
+      working-directory: ${{runner.workspace}}/build
+      run: |
+        cmake -DCMAKE_BUILD_TYPE=${{matrix.build_type}} ${{matrix.shared}} \
+              -DCMAKE_CXX_VISIBILITY_PRESET=hidden -DCMAKE_VISIBILITY_INLINES_HIDDEN=ON \
+              -DFMT_DOC=OFF -DFMT_PEDANTIC=ON -DFMT_WERROR=ON $GITHUB_WORKSPACE
+
+    - name: Build
+      working-directory: ${{runner.workspace}}/build
+      run: |
+        threads=`sysctl -n hw.logicalcpu`
+        cmake --build . --config ${{matrix.build_type}} --parallel $threads
+
+    - name: Test
+      working-directory: ${{runner.workspace}}/build
+      run: ctest -C ${{matrix.build_type}}
+      env:
+        CTEST_OUTPUT_ON_FAILURE: True

.github/workflows/windows.yml

@@ -0,0 +1,60 @@
+name: windows
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ${{matrix.os}}
+    strategy:
+      matrix:
+        # windows-2016 and windows-2019 have MSVC 2017 and 2019 installed
+        # respectively: https://github.com/actions/virtual-environments.
+        os: [windows-2016, windows-2019]
+        platform: [Win32, x64]
+        build_type: [Debug, Release]
+        standard: [11, 17, 20]
+        include:
+          - os: windows-2016
+            platform: Win32
+            build_type: Debug
+            shared: -DBUILD_SHARED_LIBS=ON
+        exclude:
+          - os: windows-2016
+            platform: Win32
+          - os: windows-2016
+            standard: 17
+          - os: windows-2016
+            standard: 20
+          - os: windows-2019
+            standard: 11
+          - os: windows-2019
+            standard: 20
+            platform: Win32
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Create Build Environment
+      run: cmake -E make_directory ${{runner.workspace}}/build
+
+    - name: Configure
+      # Use a bash shell for $GITHUB_WORKSPACE.
+      shell: bash
+      working-directory: ${{runner.workspace}}/build
+      run: |
+        cmake -DCMAKE_BUILD_TYPE=${{matrix.build_type}} ${{matrix.shared}} \
+              -A ${{matrix.platform}} \
+              -DCMAKE_CXX_STANDARD=${{matrix.standard}} \
+              $GITHUB_WORKSPACE
+
+    - name: Build
+      working-directory: ${{runner.workspace}}/build
+      run: |
+        $threads = (Get-CimInstance Win32_ComputerSystem).NumberOfLogicalProcessors
+        cmake --build . --config ${{matrix.build_type}} --parallel $threads
+
+    - name: Test
+      working-directory: ${{runner.workspace}}/build
+      run: ctest -C ${{matrix.build_type}} -V
+      env:
+        CTEST_OUTPUT_ON_FAILURE: True

.gitignore

@@ -9,6 +9,7 @@ gradle/
 gradlew*
 local.properties
 build/
+support/.cxx
 
 bin/
 /_CPack_Packages

.travis.yml

@@ -1,101 +0,0 @@
-language: cpp
-dist: trusty
-sudo: false
-
-os: linux
-
-git:
-  depth: 1
-
-env:
-  global:
-    - secure: |-
-        a1eovNn4uol9won7ghr67eD3/59oeESN+G9bWE+ecI1V6yRseG9whniGhIpC/YfMW/Qz5I
-        5sxSmFjaw9bxCISNwUIrL1O5x2AmRYTnFcXk4dFsUvlZg+WeF/aKyBYCNRM8C2ndbBmtAO
-        o1F2EwFbiso0EmtzhAPs19ujiVxkLn4=
-
-matrix:
-  include:
-      # Documentation
-    - env: BUILD=Doc
-      sudo: required
-      # g++ 6 on Linux with C++14
-    - env: COMPILER=g++-6 BUILD=Debug STANDARD=14
-      compiler: gcc
-      addons:
-        apt:
-          update: true
-          sources:
-            - ubuntu-toolchain-r-test
-          packages:
-            - g++-6
-    - env: COMPILER=g++-6 BUILD=Release STANDARD=14
-      compiler: gcc
-      addons:
-        apt:
-          update: true
-          sources:
-            - 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
-      os: osx
-    - env: BUILD=Release STANDARD=14
-      compiler: clang
-      os: osx
-      # 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:
-          update: true
-          packages:
-            - clang-6.0
-          sources:
-            - ubuntu-toolchain-r-test
-            - llvm-toolchain-trusty
-            - llvm-toolchain-trusty-6.0
-      # clang 4.0 on Linux with C++14
-    - env: COMPILER=clang++-4.0 BUILD=Debug STANDARD=11
-      compiler: clang
-      addons:
-        apt:
-          update: true
-          packages:
-            - clang-4.0
-          sources:
-            - ubuntu-toolchain-r-test
-            - llvm-toolchain-trusty
-            - llvm-toolchain-trusty-4.0
-      # g++ 4.8 on Linux with C++11
-    - env: COMPILER=g++-4.8 BUILD=Debug STANDARD=11
-      compiler: gcc
-
-before_script:
-  - if [[ "${TRAVIS_OS_NAME}" == "linux" ]]; then export CXX=${COMPILER}; fi
-  - if [[ "${BUILD}" != "Doc" ]]; then ${CXX} --version; fi
-
-script:
-  - support/travis-build.py

CMakeLists.txt

@@ -1,44 +1,63 @@
-cmake_minimum_required(VERSION 3.1.0)
+cmake_minimum_required(VERSION 3.1...3.18)
 
-# Use newer policies if available, up to most recent tested version of CMake.
-if(${CMAKE_VERSION} VERSION_LESS 3.11)
+# Fallback for using newer policies on CMake <3.12.
+if(${CMAKE_VERSION} VERSION_LESS 3.12)
   cmake_policy(VERSION ${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION})
-else()
-  cmake_policy(VERSION 3.11)
 endif()
 
 # Determine if fmt is built as a subproject (using add_subdirectory)
 # 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}")
+if (NOT DEFINED FMT_MASTER_PROJECT)
+  set(FMT_MASTER_PROJECT OFF)
+  if (CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
+    set(FMT_MASTER_PROJECT ON)
+    message(STATUS "CMake version: ${CMAKE_VERSION}")
+  endif ()
 endif ()
 
 # Joins arguments and places the results in ${result_var}.
 function(join result_var)
-  set(result )
+  set(result "")
   foreach (arg ${ARGN})
     set(result "${result}${arg}")
   endforeach ()
   set(${result_var} "${result}" PARENT_SCOPE)
 endfunction()
 
+function(enable_module target)
+  if (MSVC)
+    set(BMI ${CMAKE_CURRENT_BINARY_DIR}/${target}.ifc)
+    target_compile_options(${target}
+      PRIVATE /interface /ifcOutput ${BMI}
+      INTERFACE /reference fmt=${BMI})
+  endif ()
+  set_target_properties(${target} PROPERTIES ADDITIONAL_CLEAN_FILES ${BMI})
+  set_source_files_properties(${BMI} PROPERTIES GENERATED ON)
+endfunction()
+
+include(CMakeParseArguments)
+
 # Sets a cache variable with a docstring joined from multiple arguments:
 #   set(<variable> <value>... CACHE <type> <docstring>...)
 # This allows splitting a long docstring for readability.
 function(set_verbose)
-  cmake_parse_arguments(SET_VERBOSE "" "" "CACHE" ${ARGN})
-  list(GET SET_VERBOSE_CACHE 0 type)
-  list(REMOVE_AT SET_VERBOSE_CACHE 0)
-  join(doc ${SET_VERBOSE_CACHE})
-  set(${SET_VERBOSE_UNPARSED_ARGUMENTS} CACHE ${type} ${doc})
+  # cmake_parse_arguments is broken in CMake 3.4 (cannot parse CACHE) so use
+  # list instead.
+  list(GET ARGN 0 var)
+  list(REMOVE_AT ARGN 0)
+  list(GET ARGN 0 val)
+  list(REMOVE_AT ARGN 0)
+  list(REMOVE_AT ARGN 0)
+  list(GET ARGN 0 type)
+  list(REMOVE_AT ARGN 0)
+  join(doc ${ARGN})
+  set(${var} ${val} CACHE ${type} ${doc})
 endfunction()
 
 # Set the default CMAKE_BUILD_TYPE to Release.
 # This should be done before the project command since the latter can set
 # CMAKE_BUILD_TYPE itself (it does so for nmake).
-if (MASTER_PROJECT AND NOT CMAKE_BUILD_TYPE)
+if (FMT_MASTER_PROJECT AND NOT CMAKE_BUILD_TYPE)
   set_verbose(CMAKE_BUILD_TYPE Release CACHE STRING
               "Choose the type of build, options are: None(CMAKE_CXX_FLAGS or "
               "CMAKE_C_FLAGS used) Debug Release RelWithDebInfo MinSizeRel.")
@@ -47,20 +66,41 @@ endif ()
 project(FMT CXX)
 include(GNUInstallDirs)
 set_verbose(FMT_INC_DIR ${CMAKE_INSTALL_INCLUDEDIR} CACHE STRING
-            "Installation directory for include files, a relative path "
-            "that will be joined to ${CMAKE_INSTALL_PREFIX}, or an arbitrary absolute path.")
+            "Installation directory for include files, a relative path that "
+            "will be joined with ${CMAKE_INSTALL_PREFIX} or an absolute path.")
 
 option(FMT_PEDANTIC "Enable extra warnings and expensive tests." OFF)
 option(FMT_WERROR "Halt the compilation with an error on compiler warnings."
        OFF)
 
 # 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_DOC "Generate the doc target." ${FMT_MASTER_PROJECT})
+option(FMT_INSTALL "Generate the install target." ${FMT_MASTER_PROJECT})
+option(FMT_TEST "Generate the test target." ${FMT_MASTER_PROJECT})
 option(FMT_FUZZ "Generate the fuzz target." OFF)
 option(FMT_CUDA_TEST "Generate the cuda-test target." OFF)
 option(FMT_OS "Include core requiring OS (Windows/Posix) " ON)
+option(FMT_MODULE "Build a module instead of a traditional library." OFF)
+option(FMT_SYSTEM_HEADERS "Expose headers with marking them as system." OFF)
+
+set(FMT_CAN_MODULE OFF)
+if (CMAKE_CXX_STANDARD GREATER 17 AND
+    # msvc 16.10-pre4
+    MSVC AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 19.29.30035)
+  set(FMT_CAN_MODULE OFF)
+endif ()
+if (NOT FMT_CAN_MODULE)
+  set(FMT_MODULE OFF)
+  message(STATUS "Module support is disabled.")
+endif ()
+if (FMT_TEST AND FMT_MODULE)
+  # The tests require {fmt} to be compiled as traditional library
+  message(STATUS "Testing is incompatible with build mode 'module'.")
+endif ()
+set(FMT_SYSTEM_HEADERS_ATTRIBUTE "")
+if (FMT_SYSTEM_HEADERS)
+  set(FMT_SYSTEM_HEADERS_ATTRIBUTE SYSTEM)
+endif ()
 
 # Get version from core.h
 file(READ include/fmt/core.h core_h)
@@ -96,24 +136,36 @@ if (${index} GREATER -1)
 endif ()
 message(STATUS "Required features: ${FMT_REQUIRED_FEATURES}")
 
+if (FMT_MASTER_PROJECT AND NOT DEFINED CMAKE_CXX_VISIBILITY_PRESET)
+  set_verbose(CMAKE_CXX_VISIBILITY_PRESET hidden CACHE STRING
+              "Preset for the export of private symbols")
+  set_property(CACHE CMAKE_CXX_VISIBILITY_PRESET PROPERTY STRINGS
+               hidden default)
+endif ()
+
+if (FMT_MASTER_PROJECT AND NOT DEFINED CMAKE_VISIBILITY_INLINES_HIDDEN)
+  set_verbose(CMAKE_VISIBILITY_INLINES_HIDDEN ON CACHE BOOL
+              "Whether to add a compile flag to hide symbols of inline functions")
+endif ()
+
 if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
   set(PEDANTIC_COMPILE_FLAGS -pedantic-errors -Wall -Wextra -pedantic
       -Wold-style-cast -Wundef
       -Wredundant-decls -Wwrite-strings -Wpointer-arith
       -Wcast-qual -Wformat=2 -Wmissing-include-dirs
-      -Wcast-align -Wnon-virtual-dtor
+      -Wcast-align
       -Wctor-dtor-privacy -Wdisabled-optimization
       -Winvalid-pch -Woverloaded-virtual
-      -Wconversion -Wswitch-enum
-      -Wno-ctor-dtor-privacy -Wno-format-nonliteral -Wno-shadow)
+      -Wconversion -Wundef
+      -Wno-ctor-dtor-privacy -Wno-format-nonliteral)
   if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.6)
-      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wnoexcept
+      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS}
          -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
           -Wtrampolines -Wzero-as-null-pointer-constant -Wuseless-cast
-          -Wvector-operation-performance -Wsized-deallocation)
+          -Wvector-operation-performance -Wsized-deallocation -Wshadow)
   endif ()
   if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 6.0)
       set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wshift-overflow=2
@@ -123,8 +175,9 @@ if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
 endif ()
 
 if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
-  set(PEDANTIC_COMPILE_FLAGS -Wall -Wextra -pedantic -Wconversion
-      -Wno-sign-conversion -Wdeprecated -Wweak-vtables)
+  set(PEDANTIC_COMPILE_FLAGS -Wall -Wextra -pedantic -Wconversion -Wundef
+      -Wdeprecated -Wweak-vtables -Wshadow
+      -Wno-gnu-zero-variadic-macro-arguments)
   check_cxx_compiler_flag(-Wzero-as-null-pointer-constant HAS_NULLPTR_WARNING)
   if (HAS_NULLPTR_WARNING)
     set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS}
@@ -138,7 +191,7 @@ if (MSVC)
   set(WERROR_FLAG /WX)
 endif ()
 
-if (MASTER_PROJECT AND CMAKE_GENERATOR MATCHES "Visual Studio")
+if (FMT_MASTER_PROJECT AND CMAKE_GENERATOR MATCHES "Visual Studio")
   # If Microsoft SDK is installed create script run-msbuild.bat that
   # calls SetEnv.cmd to set up build environment and runs msbuild.
   # It is useful when building Visual Studio projects with the SDK
@@ -177,9 +230,12 @@ function(add_headers VAR)
 endfunction()
 
 # Define the fmt library, its includes and the needed defines.
-add_headers(FMT_HEADERS chrono.h color.h compile.h core.h format.h format-inl.h
-                        locale.h os.h ostream.h posix.h printf.h ranges.h)
-if (FMT_OS)
+add_headers(FMT_HEADERS args.h chrono.h color.h compile.h core.h format.h
+                        format-inl.h locale.h os.h ostream.h printf.h ranges.h
+                        xchar.h)
+if (FMT_MODULE)
+  set(FMT_SOURCES src/fmt.cc)
+elseif (FMT_OS)
   set(FMT_SOURCES src/format.cc src/os.cc)
 else()
   set(FMT_SOURCES src/format.cc)
@@ -193,7 +249,10 @@ if (HAVE_STRTOD_L)
 endif ()
 
 if (MINGW)
-  target_compile_options(fmt PUBLIC "-Wa,-mbig-obj")
+  check_cxx_compiler_flag("-Wa,-mbig-obj" FMT_HAS_MBIG_OBJ)
+  if (${FMT_HAS_MBIG_OBJ})
+    target_compile_options(fmt PUBLIC "-Wa,-mbig-obj")
+  endif()
 endif ()
 
 if (FMT_WERROR)
@@ -202,10 +261,13 @@ endif ()
 if (FMT_PEDANTIC)
   target_compile_options(fmt PRIVATE ${PEDANTIC_COMPILE_FLAGS})
 endif ()
+if (FMT_MODULE)
+  enable_module(fmt)
+endif ()
 
 target_compile_features(fmt INTERFACE ${FMT_REQUIRED_FEATURES})
 
-target_include_directories(fmt PUBLIC
+target_include_directories(fmt ${FMT_SYSTEM_HEADERS_ATTRIBUTE} PUBLIC
   $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
   $<INSTALL_INTERFACE:${FMT_INC_DIR}>)
 
@@ -223,7 +285,8 @@ if (CMAKE_BUILD_TYPE STREQUAL "Debug")
 endif ()
 
 if (BUILD_SHARED_LIBS)
-  if (UNIX AND NOT APPLE AND NOT ${CMAKE_SYSTEM_NAME} MATCHES "SunOS" AND NOT EMSCRIPTEN)
+  if (UNIX AND NOT APPLE AND NOT ${CMAKE_SYSTEM_NAME} MATCHES "SunOS" AND
+      NOT EMSCRIPTEN)
     # Fix rpmlint warning:
     # unused-direct-shlib-dependency /usr/lib/libformat.so.1.1.0 /lib/libm.so.6.
     target_link_libraries(fmt -Wl,--as-needed)
@@ -240,7 +303,7 @@ 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
+target_include_directories(fmt-header-only ${FMT_SYSTEM_HEADERS_ATTRIBUTE} INTERFACE
   $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
   $<INSTALL_INTERFACE:${FMT_INC_DIR}>)
 
@@ -248,20 +311,22 @@ target_include_directories(fmt-header-only INTERFACE
 if (FMT_INSTALL)
   include(CMakePackageConfigHelpers)
   set_verbose(FMT_CMAKE_DIR ${CMAKE_INSTALL_LIBDIR}/cmake/fmt CACHE STRING
-              "Installation directory for cmake files, a relative path "
-              "that will be joined to ${CMAKE_INSTALL_PREFIX}, or an arbitrary absolute path.")
+              "Installation directory for cmake files, a relative path that "
+              "will be joined with ${CMAKE_INSTALL_PREFIX} or an absolute "
+              "path.")
   set(version_config ${PROJECT_BINARY_DIR}/fmt-config-version.cmake)
   set(project_config ${PROJECT_BINARY_DIR}/fmt-config.cmake)
   set(pkgconfig ${PROJECT_BINARY_DIR}/fmt.pc)
   set(targets_export_name fmt-targets)
 
   set_verbose(FMT_LIB_DIR ${CMAKE_INSTALL_LIBDIR} CACHE STRING
-              "Installation directory for libraries, a relative path "
-              "that will be joined to ${CMAKE_INSTALL_PREFIX}, or an arbitrary absolute path.")
+              "Installation directory for libraries, a relative path that "
+              "will be joined to ${CMAKE_INSTALL_PREFIX} or an absolute path.")
 
   set_verbose(FMT_PKGCONFIG_DIR ${CMAKE_INSTALL_LIBDIR}/pkgconfig CACHE PATH
-              "Installation directory for pkgconfig (.pc) files, a relative path "
-              "that will be joined to ${CMAKE_INSTALL_PREFIX}, or an arbitrary absolute path.")
+              "Installation directory for pkgconfig (.pc) files, a relative "
+              "path that will be joined with ${CMAKE_INSTALL_PREFIX} or an "
+              "absolute path.")
 
   # Generate the version, config and target files into the build directory.
   write_basic_package_version_file(
@@ -282,6 +347,13 @@ if (FMT_INSTALL)
     INSTALL_DESTINATION ${FMT_CMAKE_DIR})
 
   set(INSTALL_TARGETS fmt fmt-header-only)
+
+  # Install the library and headers.
+  install(TARGETS ${INSTALL_TARGETS} EXPORT ${targets_export_name}
+          LIBRARY DESTINATION ${FMT_LIB_DIR}
+          ARCHIVE DESTINATION ${FMT_LIB_DIR}
+          RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+
   # Use a namespace because CMake provides better diagnostics for namespaced
   # imported targets.
   export(TARGETS ${INSTALL_TARGETS} NAMESPACE fmt::
@@ -294,12 +366,6 @@ if (FMT_INSTALL)
   install(EXPORT ${targets_export_name} DESTINATION ${FMT_CMAKE_DIR}
           NAMESPACE fmt::)
 
-  # Install the library and headers.
-  install(TARGETS ${INSTALL_TARGETS} EXPORT ${targets_export_name}
-          LIBRARY DESTINATION ${FMT_LIB_DIR}
-          ARCHIVE DESTINATION ${FMT_LIB_DIR}
-          RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
-
   install(FILES $<TARGET_PDB_FILE:${INSTALL_TARGETS}>
           DESTINATION ${FMT_LIB_DIR} OPTIONAL)
   install(FILES ${FMT_HEADERS} DESTINATION "${FMT_INC_DIR}/fmt")
@@ -318,11 +384,17 @@ endif ()
 # Control fuzzing independent of the unit tests.
 if (FMT_FUZZ)
   add_subdirectory(test/fuzzing)
+
+  # The FMT_FUZZ macro is used to prevent resource exhaustion in fuzzing
+  # mode and make fuzzing practically possible. It is similar to
+  # FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION but uses a different name to
+  # avoid interfering with fuzzing of projects that use {fmt}.
+  # See also https://llvm.org/docs/LibFuzzer.html#fuzzer-friendly-build-mode.
   target_compile_definitions(fmt PUBLIC FMT_FUZZ)
 endif ()
 
 set(gitignore ${PROJECT_SOURCE_DIR}/.gitignore)
-if (MASTER_PROJECT AND EXISTS ${gitignore})
+if (FMT_MASTER_PROJECT AND EXISTS ${gitignore})
   # Get the list of ignored files from .gitignore.
   file (STRINGS ${gitignore} lines)
   list(REMOVE_ITEM lines /doc/html)

CONTRIBUTING.md

@@ -14,4 +14,7 @@ exceptions:
 * snake_case should be used instead of UpperCamelCase for function and type
   names
 
+All documentation must adhere to the [Google Developer Documentation Style
+Guide](https://developers.google.com/style).
+
 Thanks for contributing!

README.rst

@@ -1,54 +1,69 @@
 {fmt}
 =====
 
-.. image:: https://travis-ci.org/fmtlib/fmt.png?branch=master
-   :target: https://travis-ci.org/fmtlib/fmt
+.. image:: https://github.com/fmtlib/fmt/workflows/linux/badge.svg
+   :target: https://github.com/fmtlib/fmt/actions?query=workflow%3Alinux
 
-.. image:: https://ci.appveyor.com/api/projects/status/ehjkiefde6gucy1v
+.. image:: https://github.com/fmtlib/fmt/workflows/macos/badge.svg
+   :target: https://github.com/fmtlib/fmt/actions?query=workflow%3Amacos
+
+.. image:: https://github.com/fmtlib/fmt/workflows/windows/badge.svg
+   :target: https://github.com/fmtlib/fmt/actions?query=workflow%3Awindows
+
+.. image:: https://ci.appveyor.com/api/projects/status/ehjkiefde6gucy1v?svg=true
    :target: https://ci.appveyor.com/project/vitaut/fmt
 
-.. image:: https://oss-fuzz-build-logs.storage.googleapis.com/badges/libfmt.svg
-   :alt: fmt is continuously fuzzed att oss-fuzz
+.. image:: https://oss-fuzz-build-logs.storage.googleapis.com/badges/fmt.svg
+   :alt: fmt is continuously fuzzed at oss-fuzz
    :target: https://bugs.chromium.org/p/oss-fuzz/issues/list?\
             colspec=ID%20Type%20Component%20Status%20Proj%20Reported%20Owner%20\
-            Summary&q=proj%3Dlibfmt&can=1
+            Summary&q=proj%3Dfmt&can=1
 
 .. image:: https://img.shields.io/badge/stackoverflow-fmt-blue.svg
    :alt: Ask questions at StackOverflow with the tag fmt
    :target: https://stackoverflow.com/questions/tagged/fmt
 
-**{fmt}** is an open-source formatting library for C++.
-It can be used as a safe and fast alternative to (s)printf and iostreams.
+**{fmt}** is an open-source formatting library providing a fast and safe
+alternative to C stdio and C++ iostreams.
 
-`Documentation <https://fmt.dev/latest/>`__
+If you like this project, please consider donating to the BYSOL
+Foundation that helps victims of political repressions in Belarus:
+https://bysol.org/en/bs/general/.
+
+`Documentation <https://fmt.dev>`__
 
 Q&A: ask questions on `StackOverflow with the tag fmt
 <https://stackoverflow.com/questions/tagged/fmt>`_.
 
+Try {fmt} in `Compiler Explorer <https://godbolt.org/z/Eq5763>`_.
+
 Features
 --------
 
-* Simple `format API <https://fmt.dev/dev/api.html>`_ with positional arguments
+* Simple `format API <https://fmt.dev/latest/api.html>`_ with positional arguments
   for localization
 * Implementation of `C++20 std::format
   <https://en.cppreference.com/w/cpp/utility/format>`__
-* `Format string syntax <https://fmt.dev/dev/syntax.html>`_ similar to the one
-  of Python's
+* `Format string syntax <https://fmt.dev/latest/syntax.html>`_ similar to Python's
   `format <https://docs.python.org/3/library/stdtypes.html#str.format>`_
+* Fast IEEE 754 floating-point formatter with correct rounding, shortness and
+  round-trip guarantees
 * Safe `printf implementation
-  <https://fmt.dev/latest/api.html#printf-formatting>`_ including
-  the POSIX extension for positional arguments
-* Extensibility: support for user-defined types
+  <https://fmt.dev/latest/api.html#printf-formatting>`_ including the POSIX
+  extension for positional arguments
+* Extensibility: `support for user-defined types
+  <https://fmt.dev/latest/api.html#formatting-user-defined-types>`_
 * High performance: faster than common standard library implementations of
-  `printf <https://en.cppreference.com/w/cpp/io/c/fprintf>`_,
-  iostreams, ``to_string`` and ``to_chars``, see `Speed tests`_ and
-  `Converting a hundred million integers to strings per second
+  ``(s)printf``, iostreams, ``to_string`` and ``to_chars``, see `Speed tests`_
+  and `Converting a hundred million integers to strings per second
   <http://www.zverovich.net/2020/06/13/fast-int-to-string-revisited.html>`_
-* Small code size both in terms of source code (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>`_ and is continuously fuzzed
+* Small code size both in terms of source code with the minimum configuration
+  consisting of just three files, ``core.h``, ``format.h`` and ``format-inl.h``,
+  and compiled code; see `Compile time and code bloat`_
+* Reliability: the library has an extensive set of `tests
+  <https://github.com/fmtlib/fmt/tree/master/test>`_ and is `continuously fuzzed
+  <https://bugs.chromium.org/p/oss-fuzz/issues/list?colspec=ID%20Type%20
+  Component%20Status%20Proj%20Reported%20Owner%20Summary&q=proj%3Dfmt&can=1>`_
 * Safety: the library is fully type safe, errors in format strings can be
   reported at compile time, automatic memory management prevents buffer overflow
   errors
@@ -57,18 +72,17 @@ Features
   <https://github.com/fmtlib/fmt/blob/master/LICENSE.rst>`_
 * `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``)
+* Clean warning-free codebase even on high warning levels such as
+  ``-Wall -Wextra -pedantic``
 * Locale-independence by default
-* Support for wide strings
 * Optional header-only configuration enabled with the ``FMT_HEADER_ONLY`` macro
 
-See the `documentation <https://fmt.dev/latest/>`_ for more details.
+See the `documentation <https://fmt.dev>`_ for more details.
 
 Examples
 --------
 
-Print ``Hello, world!`` to ``stdout``:
+**Print to stdout** (`run <https://godbolt.org/z/Tevcjh>`_)
 
 .. code:: c++
 
@@ -78,100 +92,95 @@ Print ``Hello, world!`` to ``stdout``:
       fmt::print("Hello, world!\n");
     }
 
-Format a string:
+**Format a string** (`run <https://godbolt.org/z/oK8h33>`_)
 
 .. code:: c++
 
     std::string s = fmt::format("The answer is {}.", 42);
     // s == "The answer is 42."
 
-Format a string using positional arguments:
+**Format a string using positional arguments** (`run <https://godbolt.org/z/Yn7Txe>`_)
 
 .. code:: c++
 
     std::string s = fmt::format("I'd rather be {1} than {0}.", "right", "happy");
     // s == "I'd rather be happy than right."
 
-Print a chrono duration:
+**Print chrono durations** (`run <https://godbolt.org/z/K8s4Mc>`_)
 
 .. code:: c++
 
     #include <fmt/chrono.h>
 
     int main() {
-      using namespace std::chrono_literals;
-      fmt::print("Elapsed time: {}", 42ms);
+      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 "Elapsed time: 42ms".
+Output::
 
-Check a format string at compile time:
+    Default format: 42s 100ms
+    strftime-like format: 03:15:30
+
+**Print a container** (`run <https://godbolt.org/z/MjsY7c>`_)
 
 .. code:: c++
 
-    // test.cc
-    #include <fmt/format.h>
-    std::string s = format(FMT_STRING("{:d}"), "hello");
+    #include <vector>
+    #include <fmt/ranges.h>
 
-gives a compile-time error because ``d`` is an invalid format specifier for a
-string.
-
-Use {fmt} as a safe portable replacement for ``itoa``
-(`godbolt <https://godbolt.org/g/NXmpU4>`_):
-
-.. code:: c++
-
-    fmt::memory_buffer buf;
-    format_to(buf, "{}", 42);    // replaces itoa(42, buffer, 10)
-    format_to(buf, "{:x}", 42);  // replaces itoa(42, buffer, 16)
-    // access the string with to_string(buf) or buf.data()
-
-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/format.h>
-
-    struct date {
-      int year, month, day;
-    };
-
-    template <>
-    struct fmt::formatter<date> {
-      constexpr auto parse(format_parse_context& ctx) { return ctx.begin(); }
-
-      template <typename FormatContext>
-      auto format(const date& d, FormatContext& ctx) {
-        return format_to(ctx.out(), "{}-{}-{}", d.year, d.month, d.day);
-      }
-    };
-
-    std::string s = fmt::format("The date is {}", date{2012, 12, 9});
-    // s == "The date is 2012-12-9"
-
-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++
-
-    // Prints formatted error message.
-    void vreport_error(const char* format, fmt::format_args args) {
-      fmt::print("Error: ");
-      fmt::vprint(format, args);
-    }
-    template <typename... Args>
-    void report_error(const char* format, const Args & ... args) {
-      vreport_error(format, fmt::make_format_args(args...));
+    int main() {
+      std::vector<int> v = {1, 2, 3};
+      fmt::print("{}\n", v);
     }
 
-    report_error("file not found: {}", path);
+Output::
 
-Note that ``vreport_error`` is not parameterized on argument types which can
-improve compile times and reduce code size compared to a fully parameterized
-version.
+    [1, 2, 3]
+
+**Check a format string at compile time**
+
+.. code:: c++
+
+    std::string s = fmt::format("{:d}", "I am not a number");
+
+This gives a compile-time error in C++20 because ``d`` is an invalid format
+specifier for a string.
+
+**Write a file from a single thread**
+
+.. code:: c++
+
+    #include <fmt/os.h>
+
+    int main() {
+      auto out = fmt::output_file("guide.txt");
+      out.print("Don't {}", "Panic");
+    }
+
+This can be `5 to 9 times faster than fprintf
+<http://www.zverovich.net/2020/08/04/optimal-file-buffer-size.html>`_.
+
+**Print with colors and text styles**
+
+.. code:: c++
+
+    #include <fmt/color.h>
+
+    int main() {
+      fmt::print(fg(fmt::color::crimson) | fmt::emphasis::bold,
+                 "Hello, {}!\n", "world");
+      fmt::print(fg(fmt::color::floral_white) | bg(fmt::color::slate_gray) |
+                 fmt::emphasis::underline, "Hello, {}!\n", "мир");
+      fmt::print(fg(fmt::color::steel_blue) | fmt::emphasis::italic,
+                 "Hello, {}!\n", "世界");
+    }
+
+Output on a modern terminal:
+
+.. image:: https://user-images.githubusercontent.com/
+           576385/88485597-d312f600-cf2b-11ea-9cbe-61f535a86e28.png
 
 Benchmarks
 ----------
@@ -196,14 +205,16 @@ The above results were generated by building ``tinyformat_test.cpp`` on macOS
 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>`_.
+<https://github.com/fmtlib/format-benchmark/blob/master/src/tinyformat-test.cc>`_.
 
-{fmt} is up to 10x faster than ``std::ostringstream`` and ``sprintf`` on
+{fmt} is up to 20-30x faster than ``std::ostringstream`` and ``sprintf`` on
 floating-point formatting (`dtoa-benchmark <https://github.com/fmtlib/dtoa-benchmark>`_)
-and faster than `double-conversion <https://github.com/google/double-conversion>`_:
+and faster than `double-conversion <https://github.com/google/double-conversion>`_ and
+`ryu <https://github.com/ulfjack/ryu>`_:
 
-.. image:: https://user-images.githubusercontent.com/576385/69767160-cdaca400-112f-11ea-9fc5-347c9f83caad.png
-   :target: https://fmt.dev/unknown_mac64_clang10.0.html
+.. image:: https://user-images.githubusercontent.com/576385/
+           95684665-11719600-0ba8-11eb-8e5b-972ff4e49428.png
+   :target: https://fmt.dev/unknown_mac64_clang12.0.html
 
 Compile time and code bloat
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -278,34 +289,46 @@ Then you can run the speed test::
 or the bloat test::
 
     $ make bloat-test
+    
+Migrating code
+--------------
+
+`clang-tidy-fmt <https://github.com/mikecrowe/clang-tidy-fmt>`_ provides clang
+tidy checks for converting occurrences of ``printf`` and ``fprintf`` to
+``fmt::print``.
 
 Projects using this library
 ---------------------------
 
-* `0 A.D. <https://play0ad.com/>`_: A free, open-source, cross-platform
+* `0 A.D. <https://play0ad.com/>`_: a free, open-source, cross-platform
   real-time strategy game
 
+* `2GIS <https://2gis.ru/>`_: free business listings with a city map
+
 * `AMPL/MP <https://github.com/ampl/mp>`_:
-  An open-source library for mathematical programming
+  an open-source library for mathematical programming
 
 * `Aseprite <https://github.com/aseprite/aseprite>`_:
-  Animated sprite editor & pixel art tool 
+  animated sprite editor & pixel art tool 
 
-* `AvioBook <https://www.aviobook.aero/en>`_: A comprehensive aircraft
+* `AvioBook <https://www.aviobook.aero/en>`_: a comprehensive aircraft
   operations suite
   
-* `Celestia <https://celestia.space/>`_: Real-time 3D visualization of space
+* `Blizzard Battle.net <https://battle.net/>`_: an online gaming platform
+  
+* `Celestia <https://celestia.space/>`_: real-time 3D visualization of space
 
-* `Ceph <https://ceph.com/>`_: A scalable distributed storage system
+* `Ceph <https://ceph.com/>`_: a scalable distributed storage system
 
-* `ccache <https://ccache.dev/>`_: A compiler cache
+* `ccache <https://ccache.dev/>`_: a compiler cache
 
-* `ClickHouse <https://github.com/ClickHouse/ClickHouse>`_: analytical database management system
+* `ClickHouse <https://github.com/ClickHouse/ClickHouse>`_: analytical database
+  management system
 
-* `CUAUV <http://cuauv.org/>`_: Cornell University's autonomous underwater
+* `CUAUV <https://cuauv.org/>`_: Cornell University's autonomous underwater
   vehicle
 
-* `Drake <https://drake.mit.edu/>`_: A planning, control, and analysis toolbox
+* `Drake <https://drake.mit.edu/>`_: a planning, control, and analysis toolbox
   for nonlinear dynamical systems (MIT)
 
 * `Envoy <https://lyft.github.io/envoy/>`_: C++ L7 proxy and communication bus
@@ -313,71 +336,82 @@ Projects using this library
 
 * `FiveM <https://fivem.net/>`_: a modification framework for GTA V
 
+* `fmtlog <https://github.com/MengRao/fmtlog>`_: a performant fmtlib-style
+  logging library with latency in nanoseconds
+
 * `Folly <https://github.com/facebook/folly>`_: Facebook open-source library
 
+* `Grand Mountain Adventure
+  <https://store.steampowered.com/app/1247360/Grand_Mountain_Adventure/>`_:
+  A beautiful open-world ski & snowboarding game
+
 * `HarpyWar/pvpgn <https://github.com/pvpgn/pvpgn-server>`_:
   Player vs Player Gaming Network with tweaks
 
-* `KBEngine <https://kbengine.org/>`_: An open-source MMOG server engine
+* `KBEngine <https://github.com/kbengine/kbengine>`_: an open-source MMOG server
+  engine
 
-* `Keypirinha <https://keypirinha.com/>`_: A semantic launcher for Windows
+* `Keypirinha <https://keypirinha.com/>`_: a semantic launcher for Windows
 
-* `Kodi <https://kodi.tv/>`_ (formerly xbmc): Home theater software
+* `Kodi <https://kodi.tv/>`_ (formerly xbmc): home theater software
 
-* `Knuth <https://kth.cash/>`_: High-performance Bitcoin full-node
+* `Knuth <https://kth.cash/>`_: high-performance Bitcoin full-node
 
 * `Microsoft Verona <https://github.com/microsoft/verona>`_:
-  Research programming language for concurrent ownership
+  research programming language for concurrent ownership
 
-* `MongoDB <https://mongodb.com/>`_: Distributed document database
+* `MongoDB <https://mongodb.com/>`_: distributed document database
 
-* `MongoDB Smasher <https://github.com/duckie/mongo_smasher>`_: A small tool to
+* `MongoDB Smasher <https://github.com/duckie/mongo_smasher>`_: a small tool to
   generate randomized datasets
 
-* `OpenSpace <https://openspaceproject.com/>`_: An open-source
+* `OpenSpace <https://openspaceproject.com/>`_: an open-source
   astrovisualization framework
 
 * `PenUltima Online (POL) <https://www.polserver.com/>`_:
-  An MMO server, compatible with most Ultima Online clients
+  an MMO server, compatible with most Ultima Online clients
 
-* `PyTorch <https://github.com/pytorch/pytorch>`_: An open-source machine
+* `PyTorch <https://github.com/pytorch/pytorch>`_: an open-source machine
   learning library
 
-* `quasardb <https://www.quasardb.net/>`_: A distributed, high-performance,
+* `quasardb <https://www.quasardb.net/>`_: a distributed, high-performance,
   associative database
+  
+* `Quill <https://github.com/odygrd/quill>`_: asynchronous low-latency logging library
 
-* `readpe <https://bitbucket.org/sys_dev/readpe>`_: Read Portable Executable
+* `QKW <https://github.com/ravijanjam/qkw>`_: generalizing aliasing to simplify
+  navigation, and executing complex multi-line terminal command sequences
 
-* `redis-cerberus <https://github.com/HunanTV/redis-cerberus>`_: A Redis cluster
+* `redis-cerberus <https://github.com/HunanTV/redis-cerberus>`_: a Redis cluster
   proxy
 
-* `redpanda <https://vectorized.io/redpanda>`_: A 10x faster Kafka® replacement
+* `redpanda <https://vectorized.io/redpanda>`_: a 10x faster Kafka® replacement
   for mission critical systems written in C++
 
-* `rpclib <http://rpclib.net/>`_: A modern C++ msgpack-RPC server and client
+* `rpclib <http://rpclib.net/>`_: a modern C++ msgpack-RPC server and client
   library
 
 * `Salesforce Analytics Cloud
   <https://www.salesforce.com/analytics-cloud/overview/>`_:
-  Business intelligence software
+  business intelligence software
 
-* `Scylla <https://www.scylladb.com/>`_: A Cassandra-compatible NoSQL data store
+* `Scylla <https://www.scylladb.com/>`_: a Cassandra-compatible NoSQL data store
   that can handle 1 million transactions per second on a single server
 
-* `Seastar <http://www.seastar-project.org/>`_: An advanced, open-source C++
+* `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
+* `spdlog <https://github.com/gabime/spdlog>`_: super fast C++ logging library
 
-* `Stellar <https://www.stellar.org/>`_: Financial platform
+* `Stellar <https://www.stellar.org/>`_: financial platform
 
-* `Touch Surgery <https://www.touchsurgery.com/>`_: Surgery simulator
+* `Touch Surgery <https://www.touchsurgery.com/>`_: surgery simulator
 
-* `TrinityCore <https://github.com/TrinityCore/TrinityCore>`_: Open-source
+* `TrinityCore <https://github.com/TrinityCore/TrinityCore>`_: open-source
   MMORPG framework
 
-* `Windows Terminal <https://github.com/microsoft/terminal>`_: The new Windows
-  Terminal
+* `Windows Terminal <https://github.com/microsoft/terminal>`_: the new Windows
+  terminal
 
 `More... <https://github.com/search?q=fmtlib&type=Code>`_
 
@@ -435,7 +469,7 @@ Boost Format
 
 This is a very powerful library which supports both ``printf``-like format
 strings and positional arguments. Its main drawback is performance. According to
-various benchmarks it is much slower than other methods considered here. Boost
+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`_).
 

doc/CMakeLists.txt

@@ -4,10 +4,14 @@ if (NOT DOXYGEN)
   return ()
 endif ()
 
+find_package(PythonInterp QUIET REQUIRED)
+
 add_custom_target(doc
-  COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/build.py ${FMT_VERSION}
+  COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/build.py
+                               ${FMT_VERSION}
   SOURCES api.rst syntax.rst usage.rst build.py conf.py _templates/layout.html)
 
+include(GNUInstallDirs)
 install(DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/html/
-        DESTINATION share/doc/fmt OPTIONAL
+        DESTINATION ${CMAKE_INSTALL_DATAROOTDIR}/doc/fmt OPTIONAL
         PATTERN ".doctrees" EXCLUDE)

doc/api.rst

@@ -6,17 +6,18 @@ API Reference
 
 The {fmt} library API consists of the following parts:
 
-* :ref:`fmt/core.h <core-api>`: the core API providing argument handling
-  facilities and a lightweight subset of formatting functions
-* :ref:`fmt/format.h <format-api>`: the full format API providing compile-time
-  format string checks, wide string, output iterator and user-defined type
-  support
-* :ref:`fmt/ranges.h <ranges-api>`: additional formatting support for ranges
-  and tuples
+* :ref:`fmt/core.h <core-api>`: the core API providing main formatting functions
+  for ``char``/UTF-8 with compile-time checks and minimal dependencies
+* :ref:`fmt/format.h <format-api>`: the full format API providing additional
+  formatting functions and locale support
+* :ref:`fmt/ranges.h <ranges-api>`: formatting of ranges and tuples
 * :ref:`fmt/chrono.h <chrono-api>`: date and time formatting
 * :ref:`fmt/compile.h <compile-api>`: format string compilation
+* :ref:`fmt/color.h <color-api>`: terminal color and text style
+* :ref:`fmt/os.h <os-api>`: system APIs
 * :ref:`fmt/ostream.h <ostream-api>`: ``std::ostream`` support
 * :ref:`fmt/printf.h <printf-api>`: ``printf`` formatting
+* :ref:`fmt/xchar.h <xchar-api>`: optional ``wchar_t`` support 
 
 All functions and types provided by the library reside in namespace ``fmt`` and
 macros have prefix ``FMT_``.
@@ -26,34 +27,66 @@ macros have prefix ``FMT_``.
 Core API
 ========
 
-``fmt/core.h`` defines the core API which provides argument handling facilities
-and a lightweight subset of formatting functions. In the header-only mode
-include ``fmt/format.h`` instead of ``fmt/core.h``.
+``fmt/core.h`` defines the core API which provides main formatting functions for
+``char``/UTF-8 with compile-time checks. It has minimal include dependencies for
+better compile times. This header is only beneficial when using {fmt} as a
+library and not in the header-only mode.
 
 The following functions use :ref:`format string syntax <syntax>`
 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.
+<https://docs.python.org/3/library/stdtypes.html#str.format>`_.
+They take *fmt* 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. A function taking *format_str* doesn't
-participate in an overload resolution if the latter is not a string.
+*fmt* 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. `~fmt::format_string` is a format string which can be
+implicitly constructed from a string literal or a ``constexpr`` string and is
+checked at compile time in C++20. To pass a runtime format string wrap it in
+`fmt::runtime`.
 
 *args* is an argument list representing objects to be formatted.
 
 .. _format:
 
-.. doxygenfunction:: format(const S&, Args&&...)
-.. doxygenfunction:: vformat(const S&, basic_format_args<buffer_context<type_identity_t<Char>>>)
+.. doxygenfunction:: format(format_string<T...> fmt, T&&... args) -> std::string
+.. doxygenfunction:: vformat(string_view fmt, format_args args) -> std::string
+
+.. doxygenfunction:: format_to(OutputIt out, format_string<T...> fmt, T&&... args) -> OutputIt
+.. doxygenfunction:: format_to_n(OutputIt out, size_t n, format_string<T...> fmt, T&&... args) -> format_to_n_result<OutputIt>
+.. doxygenfunction:: formatted_size(format_string<T...> fmt, T&&... args) -> size_t
+
+.. doxygenstruct:: fmt::format_to_n_result
+   :members:
 
 .. _print:
 
-.. doxygenfunction:: print(const S&, Args&&...)
-.. doxygenfunction:: vprint(string_view, format_args)
+.. doxygenfunction:: fmt::print(format_string<T...> fmt, T&&... args)
+.. doxygenfunction:: fmt::vprint(string_view fmt, format_args args)
 
-.. doxygenfunction:: print(std::FILE *, const S&, Args&&...)
-.. doxygenfunction:: vprint(std::FILE *, string_view, format_args)
+.. doxygenfunction:: print(std::FILE *f, format_string<T...> fmt, T&&... args)
+.. doxygenfunction:: vprint(std::FILE *f, string_view fmt, format_args args)
+
+Compile-time Format String Checks
+---------------------------------
+
+Compile-time checks are enabled when using ``FMT_STRING``. They support built-in
+and string types as well as user-defined types with ``constexpr`` ``parse``
+functions in their ``formatter`` specializations.
+Requires C++14 and is a no-op in C++11.
+
+.. doxygendefine:: FMT_STRING
+
+To force the use of compile-time checks, define the preprocessor variable
+``FMT_ENFORCE_COMPILE_STRING``. When set, functions accepting ``FMT_STRING``
+will fail to compile with regular strings. Runtime-checked
+formatting is still possible using ``fmt::vformat``, ``fmt::vprint``, etc.
+
+.. doxygenclass:: fmt::basic_format_string
+   :members:
+
+.. doxygentypedef:: fmt::format_string
+
+.. doxygenfunction:: fmt::runtime(const S&)
 
 Named Arguments
 ---------------
@@ -65,6 +98,35 @@ Named arguments are not supported in compile-time checks at the moment.
 Argument Lists
 --------------
 
+You can create your own formatting function with compile-time checks and small
+binary footprint, for example (https://godbolt.org/z/oba4Mc):
+
+.. code:: c++
+
+    #include <fmt/format.h>
+
+    void vlog(const char* file, int line, fmt::string_view format,
+              fmt::format_args args) {
+      fmt::print("{}: {}: ", file, line);
+      fmt::vprint(format, args);
+    }
+
+    template <typename S, typename... Args>
+    void log(const char* file, int line, const S& format, Args&&... args) {
+      vlog(file, line, format,
+          fmt::make_args_checked<Args...>(format, args...));
+    }
+
+    #define MY_LOG(format, ...) \
+      log(__FILE__, __LINE__, FMT_STRING(format), __VA_ARGS__)
+
+    MY_LOG("invalid squishiness: {}", 42);
+
+Note that ``vlog`` is not parameterized on argument types which improves compile
+times and reduces binary code size compared to a fully parameterized version.
+
+.. doxygenfunction:: fmt::make_args_checked(const S&, const remove_reference_t<Args>&...)
+
 .. doxygenfunction:: fmt::make_format_args(const Args&...)
 
 .. doxygenclass:: fmt::format_arg_store
@@ -76,11 +138,16 @@ Argument Lists
 .. doxygenclass:: fmt::basic_format_args
    :members:
 
-.. doxygenstruct:: fmt::format_args
+.. doxygentypedef:: fmt::format_args
 
 .. doxygenclass:: fmt::basic_format_arg
    :members:
 
+.. doxygenclass:: fmt::basic_format_context
+   :members:
+
+.. doxygentypedef:: fmt::format_context
+
 Compatibility
 -------------
 
@@ -88,12 +155,11 @@ Compatibility
    :members:
 
 .. doxygentypedef:: fmt::string_view
-.. doxygentypedef:: fmt::wstring_view
 
 Locale
 ------
 
-All formatting is locale-independent by default. Use the ``'n'`` format
+All formatting is locale-independent by default. Use the ``'L'`` format
 specifier to insert the appropriate number separator characters from the
 locale::
 
@@ -108,17 +174,10 @@ locale::
 Format API
 ==========
 
-``fmt/format.h`` defines the full format API providing compile-time format
-string checks, wide string, output iterator and user-defined type support.
+``fmt/format.h`` defines the full format API providing additional formatting
+functions and locale support.
 
-Compile-time Format String Checks
----------------------------------
-
-Compile-time checks are supported for built-in and string types as well as
-user-defined types with ``constexpr`` ``parse`` functions in their ``formatter``
-specializations.
-
-.. doxygendefine:: FMT_STRING
+.. _udt:
 
 Formatting User-defined Types
 -----------------------------
@@ -128,16 +187,16 @@ template and implement ``parse`` and ``format`` methods::
 
   #include <fmt/format.h>
 
-  struct point { double x, y; };
+  struct point {
+    double x, y;
+  };
 
-  template <>
-  struct fmt::formatter<point> {
+  template <> struct fmt::formatter<point> {
     // Presentation format: 'f' - fixed, 'e' - exponential.
     char presentation = 'f';
 
     // Parses format specifications of the form ['f' | 'e'].
-    constexpr auto parse(format_parse_context& ctx) {
-    // auto parse(format_parse_context &ctx) -> decltype(ctx.begin()) // c++11
+    constexpr auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
       // [ctx.begin(), ctx.end()) is a character range that contains a part of
       // the format string starting from the format specifications to be parsed,
       // e.g. in
@@ -154,8 +213,7 @@ template and implement ``parse`` and ``format`` methods::
       if (it != end && (*it == 'f' || *it == 'e')) presentation = *it++;
 
       // Check if reached the end of the range:
-      if (it != end && *it != '}')
-        throw format_error("invalid format");
+      if (it != end && *it != '}') throw format_error("invalid format");
 
       // Return an iterator past the end of the parsed range:
       return it;
@@ -164,13 +222,11 @@ template and implement ``parse`` and ``format`` methods::
     // Formats the point p using the parsed format specification (presentation)
     // stored in this formatter.
     template <typename FormatContext>
-    auto format(const point& p, FormatContext& ctx) {
-    // auto format(const point &p, FormatContext &ctx) -> decltype(ctx.out()) // c++11
+    auto format(const point& p, FormatContext& ctx) -> decltype(ctx.out()) {
       // ctx.out() is an output iterator to write to.
-      return format_to(
-          ctx.out(),
-          presentation == 'f' ? "({:.1f}, {:.1f})" : "({:.1e}, {:.1e})",
-          p.x, p.y);
+      return presentation == 'f'
+                ? format_to(ctx.out(), "({:.1f}, {:.1f})", p.x, p.y)
+                : format_to(ctx.out(), "({:.1e}, {:.1e})", p.x, p.y);
     }
   };
 
@@ -237,44 +293,38 @@ You can also write a formatter for a hierarchy of classes::
     fmt::print("{}", a); // prints "B"
   }
 
+If a type provides both a ``formatter`` specialization and an implicit
+conversion to a formattable type, the specialization takes precedence over the
+conversion.
+
 .. doxygenclass:: fmt::basic_format_parse_context
    :members:
 
-Output Iterator Support
------------------------
-
-.. doxygenfunction:: fmt::format_to(OutputIt, const S&, Args&&...)
-.. doxygenfunction:: fmt::format_to_n(OutputIt, size_t, const S&, const Args&...)
-.. doxygenstruct:: fmt::format_to_n_result
-   :members:
-
 Literal-based API
 -----------------
 
 The following user-defined literals are defined in ``fmt/format.h``.
 
-.. doxygenfunction:: operator""_format(const char *, size_t)
+.. doxygenfunction:: operator""_format(const char *s, size_t n) -> detail::udl_formatter<char> 
 
-.. doxygenfunction:: operator""_a(const char *, size_t)
+.. doxygenfunction:: operator""_a(const char *s, size_t) -> detail::udl_arg<char>
 
 Utilities
 ---------
 
-.. doxygenstruct:: fmt::is_char
+.. doxygenfunction:: fmt::ptr(T p) -> const void*
+.. doxygenfunction:: fmt::ptr(const std::unique_ptr<T> &p) -> const void*
+.. doxygenfunction:: fmt::ptr(const std::shared_ptr<T> &p) -> const void*
 
-.. doxygentypedef:: fmt::char_t
+.. doxygenfunction:: fmt::to_string(const T &value) -> std::string
 
-.. doxygenfunction:: fmt::formatted_size(string_view, const Args&...)
+.. doxygenfunction:: fmt::to_string_view(const Char *s) -> basic_string_view<Char>
 
-.. doxygenfunction:: fmt::to_string(const T&)
+.. doxygenfunction:: fmt::join(Range &&range, string_view sep) -> join_view<detail::iterator_t<Range>, detail::sentinel_t<Range>>
 
-.. doxygenfunction:: fmt::to_wstring(const T&)
+.. doxygenfunction:: fmt::join(It begin, Sentinel end, string_view sep) -> join_view<It, Sentinel>
 
-.. doxygenfunction:: fmt::to_string_view(const Char *)
-
-.. doxygenfunction:: fmt::join(const Range&, string_view)
-
-.. doxygenfunction:: fmt::join(It, Sentinel, string_view)
+.. doxygenfunction:: fmt::group_digits(T value) -> group_digits_view<T>
 
 .. doxygenclass:: fmt::detail::buffer
    :members:
@@ -286,20 +336,14 @@ Utilities
 System Errors
 -------------
 
-fmt does not use ``errno`` to communicate errors to the user, but it may call
-system functions which set ``errno``. Users should not make any assumptions about
-the value of ``errno`` being preserved by library functions.
+{fmt} does not use ``errno`` to communicate errors to the user, but it may call
+system functions which set ``errno``. Users should not make any assumptions
+about the value of ``errno`` being preserved by library functions.
 
-.. doxygenclass:: fmt::system_error
-   :members:
+.. doxygenfunction:: fmt::system_error
 
 .. doxygenfunction:: fmt::format_system_error
 
-.. doxygenclass:: fmt::windows_error
-   :members:
-
-.. _formatstrings:
-
 Custom Allocators
 -----------------
 
@@ -318,8 +362,8 @@ allocator::
 
     custom_string vformat(custom_allocator alloc, fmt::string_view format_str,
                           fmt::format_args args) {
-      custom_memory_buffer buf(alloc);
-      fmt::vformat_to(buf, format_str, args);
+      auto buf = custom_memory_buffer(alloc);
+      fmt::vformat_to(std::back_inserter(buf), format_str, args);
       return custom_string(buf.data(), buf.size(), alloc);
     }
 
@@ -330,10 +374,10 @@ allocator::
       return vformat(alloc, format_str, fmt::make_format_args(args...));
     }
 
-The allocator will be used for the output container only. If you are using named
-arguments, the container that stores pointers to them will be allocated using
-the default allocator. Also floating-point formatting falls back on ``sprintf``
-which may do allocations.
+The allocator will be used for the output container only. Formatting functions
+normally don't do any allocations for built-in and string types except for
+non-default floating-point formatting that occasionally falls back on
+``sprintf``.
 
 .. _ranges-api:
 
@@ -365,41 +409,84 @@ Using ``fmt::join``, you can separate tuple elements with a custom separator::
 Date and Time Formatting
 ========================
 
-The library supports `strftime
-<http://en.cppreference.com/w/cpp/chrono/c/strftime>`_-like date and time
-formatting::
+``fmt/chrono.h`` provides formatters for
+
+* `std::chrono::duration <https://en.cppreference.com/w/cpp/chrono/duration>`_
+* `std::chrono::time_point
+  <https://en.cppreference.com/w/cpp/chrono/time_point>`_
+* `std::tm <https://en.cppreference.com/w/cpp/chrono/c/tm>`_
+
+The format syntax is described in :ref:`chrono-specs`.
+
+**Example**::
 
   #include <fmt/chrono.h>
 
-  std::time_t t = std::time(nullptr);
-  // Prints "The date is 2016-04-29." (with the current date)
-  fmt::print("The date is {:%Y-%m-%d}.", fmt::localtime(t));
+  int main() {
+    std::time_t t = std::time(nullptr);
 
-The format string syntax is described in the documentation of
-`strftime <http://en.cppreference.com/w/cpp/chrono/c/strftime>`_.
+    // Prints "The date is 2020-11-07." (with the current date):
+    fmt::print("The date is {:%Y-%m-%d}.", fmt::localtime(t));
+
+    using namespace std::literals::chrono_literals;
+
+    // Prints "Default format: 42s 100ms":
+    fmt::print("Default format: {} {}\n", 42s, 100ms);
+
+    // Prints "strftime-like format: 03:15:30":
+    fmt::print("strftime-like format: {:%H:%M:%S}\n", 3h + 15min + 30s);
+  }
+
+.. doxygenfunction:: localtime(std::time_t time)
+
+.. doxygenfunction:: gmtime(std::time_t time)
 
 .. _compile-api:
 
 Format string compilation
 =========================
 
-``fmt/compile.h`` provides format string compilation support. Format strings
-are parsed at compile time and converted into efficient formatting code. This
-supports arguments of built-in and string types as well as user-defined types
-with ``constexpr`` ``parse`` functions in their ``formatter`` specializations.
-Format string compilation can generate more binary code compared to the default
-API and is only recommended in places where formatting is a performance
-bottleneck.
+``fmt/compile.h`` provides format string compilation support when using
+``FMT_COMPILE``. Format strings are parsed, checked and converted into efficient
+formatting code at compile-time. This supports arguments of built-in and string
+types as well as user-defined types with ``constexpr`` ``parse`` functions in
+their ``formatter`` specializations. Format string compilation can generate more
+binary code compared to the default API and is only recommended in places where
+formatting is a performance bottleneck.
 
 .. doxygendefine:: FMT_COMPILE
 
+.. _color-api:
+
+Terminal color and text style
+=============================
+
+``fmt/color.h`` provides support for terminal color and text style output.
+
+.. doxygenfunction:: print(const text_style &ts, const S &format_str, const Args&... args)
+
+.. doxygenfunction:: fg(detail::color_type)
+
+.. doxygenfunction:: bg(detail::color_type)
+
+.. _os-api:
+
+System APIs
+===========
+
+.. doxygenclass:: fmt::ostream
+   :members:
+
+.. doxygenfunction:: fmt::windows_error
+   :members:
+
 .. _ostream-api:
 
 ``std::ostream`` Support
 ========================
 
 ``fmt/ostream.h`` provides ``std::ostream`` support including formatting of
-user-defined types that have overloaded ``operator<<``::
+user-defined types that have an overloaded insertion operator (``operator<<``)::
 
   #include <fmt/ostream.h>
 
@@ -416,7 +503,10 @@ user-defined types that have overloaded ``operator<<``::
   std::string s = fmt::format("The date is {}", date(2012, 12, 9));
   // s == "The date is 2012-12-9"
 
-.. doxygenfunction:: print(std::basic_ostream<Char>&, const S&, Args&&...)
+{fmt} only supports insertion operators that are defined in the same namespaces
+as the types they format and can be found with the argument-dependent lookup.
+
+.. doxygenfunction:: print(std::basic_ostream<Char> &os, const S &format_str, Args&&... args)
 
 .. _printf-api:
 
@@ -425,18 +515,32 @@ user-defined types that have overloaded ``operator<<``::
 
 The header ``fmt/printf.h`` provides ``printf``-like formatting functionality.
 The following functions use `printf format string syntax
-<http://pubs.opengroup.org/onlinepubs/009695399/functions/fprintf.html>`_ with
+<https://pubs.opengroup.org/onlinepubs/009695399/functions/fprintf.html>`_ with
 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(const S&, const Args&...)
+.. doxygenfunction:: printf(const S &format_str, const T&... args)
 
-.. doxygenfunction:: fprintf(std::FILE *, const S&, const Args&...)
+.. doxygenfunction:: fprintf(std::FILE *f, const S &fmt, const T&... args) -> int
 
-.. doxygenfunction:: fprintf(std::basic_ostream<Char>&, const S&, const Args&...)
+.. doxygenfunction:: sprintf(const S&, const T&...)
 
-.. doxygenfunction:: sprintf(const S&, const Args&...)
+.. _xchar-api:
+
+``wchar_t`` Support
+===================
+
+The optional header ``fmt/xchar.h`` provides support for ``wchar_t`` and exotic
+character types.
+
+.. doxygenstruct:: fmt::is_char
+
+.. doxygentypedef:: fmt::wstring_view
+
+.. doxygentypedef:: fmt::wformat_context
+
+.. doxygenfunction:: fmt::to_wstring(const T &value)
 
 Compatibility with C++20 ``std::format``
 ========================================
@@ -447,9 +551,6 @@ differences:
 
 * Names are defined in the ``fmt`` namespace instead of ``std`` to avoid
   collisions with standard library implementations.
-* The ``'L'`` format specifier cannot be combined with presentation specifiers
-  yet.
 * Width calculation doesn't use grapheme clusterization. The latter has been
   implemented in a separate branch but hasn't been integrated yet.
-* Chrono formatting doesn't support C++20 date types since they are not provided
-  by standard library implementations.
+* Most C++20 chrono types are not supported yet.

doc/basic-bootstrap/layout.html

@@ -90,12 +90,14 @@
         VERSION:     '{{ release|e }}',
         COLLAPSE_INDEX: false,
         FILE_SUFFIX: '{{ '' if no_search_suffix else file_suffix }}',
+        LINK_SUFFIX: '{{ link_suffix }}',
+        SOURCELINK_SUFFIX: '{{ sourcelink_suffix }}',
         HAS_SOURCE:  {{ has_source|lower }},
         SOURCELINK_SUFFIX:  '{{ sourcelink_suffix }}'
       };
     </script>
     {%- for scriptfile in script_files %}
-    <script type="text/javascript" src="{{ pathto(scriptfile, 1) }}"></script>
+    {{ js_tag(scriptfile) }}
     {%- endfor %}
 {%- endmacro %}
 

doc/build.py

@@ -1,63 +1,35 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # Build the documentation.
 
-from __future__ import print_function
-import errno, os, shutil, sys, tempfile
-from subprocess import check_call, check_output, CalledProcessError, Popen, PIPE
-from distutils.version import LooseVersion
+import errno, os, re, sys
+from subprocess import check_call, CalledProcessError, Popen, PIPE, STDOUT
 
-versions = ['1.0.0', '1.1.0', '2.0.0', '3.0.2', '4.0.0', '4.1.0', '5.0.0', '5.1.0', '5.2.0', '5.2.1', '5.3.0', '6.0.0', '6.1.0', '6.1.1', '6.1.2', '6.2.0', '6.2.1', '7.0.0', '7.0.1']
+versions = ['1.0.0', '1.1.0', '2.0.0', '3.0.2', '4.0.0', '4.1.0', '5.0.0', '5.1.0', '5.2.0', '5.2.1', '5.3.0', '6.0.0', '6.1.0', '6.1.1', '6.1.2', '6.2.0', '6.2.1', '7.0.0', '7.0.1', '7.0.2', '7.0.3', '7.1.0', '7.1.1', '7.1.2', '7.1.3', '8.0.0', '8.0.1']
 
-def pip_install(package, commit=None, **kwargs):
-  "Install package using pip."
-  min_version = kwargs.get('min_version')
-  if min_version:
-    from pkg_resources import get_distribution, DistributionNotFound
-    try:
-      installed_version = get_distribution(os.path.basename(package)).version
-      if LooseVersion(installed_version) >= min_version:
-        print('{} {} already installed'.format(package, min_version))
-        return
-    except DistributionNotFound:
-      pass
-  if commit:
-    package = 'git+https://github.com/{0}.git@{1}'.format(package, commit)
-  print('Installing {0}'.format(package))
-  check_call(['pip', 'install', package])
+class Pip:
+  def __init__(self, venv_dir):
+    self.path = os.path.join(venv_dir, 'bin', 'pip')
 
-def create_build_env(dirname='virtualenv'):
+  def install(self, package, commit=None):
+    "Install package using pip."
+    if commit:
+      package = 'git+https://github.com/{0}.git@{1}'.format(package, commit)
+    print('Installing {0}'.format(package))
+    check_call([self.path, 'install', package])
+
+def create_build_env(venv_dir='virtualenv'):
   # Create virtualenv.
-  if not os.path.exists(dirname):
-    check_call(['virtualenv', dirname])
-  import sysconfig
-  scripts_dir = os.path.basename(sysconfig.get_path('scripts'))
-  activate_this_file = os.path.join(dirname, scripts_dir, 'activate_this.py')
-  with open(activate_this_file) as f:
-    exec(f.read(), dict(__file__=activate_this_file))
-  # Import get_distribution after activating virtualenv to get info about
-  # the correct packages.
-  from pkg_resources import get_distribution, DistributionNotFound
-  # Upgrade pip because installation of sphinx with pip 1.1 available on Travis
-  # is broken (see #207) and it doesn't support the show command.
-  pip_version = get_distribution('pip').version
-  if LooseVersion(pip_version) < LooseVersion('1.5.4'):
-    print("Updating pip")
-    check_call(['pip', 'install', '--upgrade', 'pip'])
-  # Upgrade distribute because installation of sphinx with distribute 0.6.24
-  # available on Travis is broken (see #207).
-  try:
-    distribute_version = get_distribution('distribute').version
-    if LooseVersion(distribute_version) <= LooseVersion('0.6.24'):
-      print("Updating distribute")
-      check_call(['pip', 'install', '--upgrade', 'distribute'])
-  except DistributionNotFound:
-    pass
-  # Install Sphinx and Breathe.
-  pip_install('sphinx-doc/sphinx', '12b83372ac9316e8cbe86e7fed889296a4cc29ee',
-              min_version='1.4.1.dev20160531')
-  pip_install('michaeljones/breathe',
-              '129222318f7c8f865d2631e7da7b033567e7f56a',
-              min_version='4.2.0')
+  if not os.path.exists(venv_dir):
+    check_call(['python3', '-m', 'venv', venv_dir])
+  # Install Sphinx and Breathe. Require the exact version of Sphinx which is
+  # compatible with Breathe.
+  pip = Pip(venv_dir)
+  pip.install('wheel')
+  pip.install('six')
+  # See: https://github.com/sphinx-doc/sphinx/issues/9777
+  pip.install('docutils==0.17.1')
+  pip.install('sphinx-doc/sphinx', 'v3.3.0')
+  pip.install('michaeljones/breathe', 'v4.25.0')
 
 def build_docs(version='dev', **kwargs):
   doc_dir = kwargs.get('doc_dir', os.path.dirname(os.path.realpath(__file__)))
@@ -66,16 +38,17 @@ def build_docs(version='dev', **kwargs):
       'include_dir', os.path.join(os.path.dirname(doc_dir), 'include', 'fmt'))
   # Build docs.
   cmd = ['doxygen', '-']
-  p = Popen(cmd, stdin=PIPE)
+  p = Popen(cmd, stdin=PIPE, stdout=PIPE, stderr=STDOUT)
   doxyxml_dir = os.path.join(work_dir, 'doxyxml')
-  p.communicate(input=r'''
+  out, _ = p.communicate(input=r'''
       PROJECT_NAME      = fmt
       GENERATE_LATEX    = NO
       GENERATE_MAN      = NO
       GENERATE_RTF      = NO
       CASE_SENSE_NAMES  = NO
-      INPUT             = {0}/core.h {0}/compile.h {0}/format.h {0}/os.h \
-                          {0}/ostream.h {0}/printf.h {0}/time.h
+      INPUT             = {0}/chrono.h {0}/color.h {0}/core.h {0}/compile.h \
+                          {0}/format.h {0}/os.h {0}/ostream.h {0}/printf.h \
+                          {0}/xchar.h
       QUIET             = YES
       JAVADOC_AUTOBRIEF = YES
       AUTOLINK_SUPPORT  = NO
@@ -86,6 +59,8 @@ def build_docs(version='dev', **kwargs):
       ALIASES          += "endrst=\endverbatim"
       MACRO_EXPANSION   = YES
       PREDEFINED        = _WIN32=1 \
+                          __linux__=1 \
+                          FMT_ENABLE_IF(...)= \
                           FMT_USE_VARIADIC_TEMPLATES=1 \
                           FMT_USE_RVALUE_REFERENCES=1 \
                           FMT_USE_USER_DEFINED_LITERALS=1 \
@@ -94,20 +69,39 @@ def build_docs(version='dev', **kwargs):
                           "FMT_BEGIN_NAMESPACE=namespace fmt {{" \
                           "FMT_END_NAMESPACE=}}" \
                           "FMT_STRING_ALIAS=1" \
-                          "FMT_ENABLE_IF(B)="
-      EXCLUDE_SYMBOLS   = fmt::internal::* StringValue write_str
+                          "FMT_VARIADIC(...)=" \
+                          "FMT_VARIADIC_W(...)=" \
+                          "FMT_DOC=1"
+      EXCLUDE_SYMBOLS   = fmt::formatter fmt::printf_formatter fmt::arg_join \
+                          fmt::basic_format_arg::handle
     '''.format(include_dir, doxyxml_dir).encode('UTF-8'))
+  out = out.decode('utf-8')
+  internal_symbols = [
+    'fmt::detail::.*',
+    'basic_data<>',
+    'fmt::type_identity',
+    'fmt::dynamic_formatter'
+  ]
+  noisy_warnings = [
+    'warning: (Compound|Member .* of class) (' + '|'.join(internal_symbols) + \
+      ') is not documented.',
+    'warning: Internal inconsistency: .* does not belong to any container!'
+  ]
+  for w in noisy_warnings:
+      out = re.sub('.*' + w + '\n', '', out)
+  print(out)
   if p.returncode != 0:
     raise CalledProcessError(p.returncode, cmd)
+
   html_dir = os.path.join(work_dir, 'html')
   main_versions = reversed(versions[-3:])
-  check_call(['sphinx-build',
+  check_call([os.path.join(work_dir, 'virtualenv', 'bin', 'sphinx-build'),
               '-Dbreathe_projects.format=' + os.path.abspath(doxyxml_dir),
               '-Dversion=' + version, '-Drelease=' + version,
               '-Aversion=' + version, '-Aversions=' + ','.join(main_versions),
               '-b', 'html', doc_dir, html_dir])
   try:
-    check_call(['lessc', '--clean-css',
+    check_call(['lessc', '--verbose', '--clean-css',
                 '--include-path=' + os.path.join(doc_dir, 'bootstrap'),
                 os.path.join(doc_dir, 'fmt.less'),
                 os.path.join(html_dir, '_static', 'fmt.css')])

doc/fmt.less

@@ -56,6 +56,11 @@ div.sphinxsidebar {
   padding: 0;
 }
 
+// Override center alignment in tables.
+td {
+  text-align: left;
+}
+
 p.rubric {
   margin-top: 10px;
 }

doc/index.rst

@@ -23,24 +23,26 @@ Format API
 
 The format API is similar in spirit to the C ``printf`` family of function but
 is safer, simpler and several times `faster
-<http://zverovich.net/2013/09/07/integer-to-string-conversion-in-cplusplus.html>`_
+<https://www.zverovich.net/2020/06/13/fast-int-to-string-revisited.html>`_
 than common standard library implementations.
 The `format string syntax <syntax.html>`_ is similar to the one used by
-`str.format <http://docs.python.org/3/library/stdtypes.html#str.format>`_ in
+`str.format <https://docs.python.org/3/library/stdtypes.html#str.format>`_ in
 Python:
 
 .. code:: c++
 
-  fmt::format("The answer is {}.", 42);
+  std::string s = fmt::format("The answer is {}.", 42);
   
 The ``fmt::format`` function returns a string "The answer is 42.". You can use
 ``fmt::memory_buffer`` to avoid constructing ``std::string``:
 
 .. code:: c++
 
-  fmt::memory_buffer out;
-  format_to(out, "For a moment, {} happened.", "nothing");
-  out.data(); // returns a pointer to the formatted data
+  auto out = fmt::memory_buffer();
+  format_to(std::back_inserter(out),
+            "For a moment, {} happened.", "nothing");
+  auto data = out.data(); // pointer to the formatted data
+  auto size = out.size(); // size of the formatted data
 
 The ``fmt::print`` function performs formatting and writes the result to a stream:
 
@@ -48,21 +50,19 @@ The ``fmt::print`` function performs formatting and writes the result to a strea
 
   fmt::print(stderr, "System error code = {}\n", errno);
 
-The file argument can be omitted in which case the function prints to
-``stdout``:
+If you omit the file argument the function will print to ``stdout``:
 
 .. code:: c++
 
   fmt::print("Don't {}\n", "panic");
 
-The Format API also supports positional arguments useful for localization:
+The format API also supports positional arguments useful for localization:
 
 .. code:: c++
 
   fmt::print("I'd rather be {1} than {0}.", "right", "happy");
 
-Named arguments can be created with ``fmt::arg``. This makes it easier to track 
-what goes where when multiple arguments are being formatted:
+You can pass named arguments with ``fmt::arg``:
 
 .. code:: c++
 
@@ -91,16 +91,17 @@ time. For example, the code
 
   fmt::format("The answer is {:d}", "forty-two");
 
-throws a ``format_error`` exception with description "unknown format code 'd' for
-string", because the argument ``"forty-two"`` is a string while the format code
-``d`` only applies to integers, while
+throws the ``format_error`` exception because the argument ``"forty-two"`` is a
+string while the format code ``d`` only applies to integers.
+
+The code
 
 .. code:: c++
 
   format(FMT_STRING("The answer is {:d}"), "forty-two");
 
-reports a compile-time error for the same reason on compilers that support
-relaxed ``constexpr``. See `here <api.html#c.fmt>`_ for details.
+reports a compile-time error on compilers that support relaxed ``constexpr``.
+See `here <api.html#c.fmt>`_ for details.
 
 The following code
 
@@ -109,21 +110,15 @@ The following code
   fmt::format("Cyrillic letter {}", L'\x42e');
   
 produces a compile-time error because wide character ``L'\x42e'`` cannot be
-formatted into a narrow string. You can use a wide format string instead:
-
-.. code:: c++
-
-  fmt::format(L"Cyrillic letter {}", L'\x42e');
-
-For comparison, writing a wide character to ``std::ostream`` results in
-its numeric value being written to the stream (i.e. 1070 instead of letter 'ю'
-which is represented by ``L'\x42e'`` if we use Unicode) which is rarely what is
-needed.
+formatted into a narrow string. For comparison, writing a wide character to
+``std::ostream`` results in its numeric value being written to the stream
+(i.e. 1070 instead of letter 'ю' which is represented by ``L'\x42e'`` if we
+use Unicode) which is rarely desirable.
 
 Compact Binary Code
 -------------------
 
-The library is designed to produce compact per-call compiled code. For example
+The library produces compact per-call compiled code. For example
 (`godbolt <https://godbolt.org/g/TZU4KF>`_),
 
 .. code:: c++
@@ -144,8 +139,8 @@ compiles to just
      mov rcx, rsp
      mov edi, offset .L.str
      mov esi, 17
-     mov edx, 2
-     call fmt::v5::vprint(fmt::v5::basic_string_view<char>, fmt::v5::format_args)
+     mov edx, 1
+     call fmt::v7::vprint(fmt::v7::basic_string_view<char>, fmt::v7::format_args)
      xor eax, eax
      add rsp, 24
      ret
@@ -167,20 +162,19 @@ The library is highly portable and relies only on a small set of C++11 features:
 * deleted functions
 * alias templates
 
-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.
+These are available in GCC 4.8, Clang 3.4, MSVC 19.0 (2015) and more recent
+compiler version. For older compilers use {fmt} `version 4.x
+<https://github.com/fmtlib/fmt/releases/tag/4.1.0>`_ which is maintained and
+only requires C++98.
 
-The output of all formatting functions is consistent across platforms. In
-particular, formatting a floating-point infinity always gives ``inf`` while the
-output of ``printf`` is platform-dependent. For example,
+The output of all formatting functions is consistent across platforms.
+For example,
 
 .. code::
 
   fmt::print("{}", std::numeric_limits<double>::infinity());
 
-always prints ``inf``.
+always prints ``inf`` while the output of ``printf`` is platform-dependent.
 
 .. _ease-of-use:
 
@@ -192,11 +186,13 @@ just three header files and no external dependencies.
 A permissive MIT `license <https://github.com/fmtlib/fmt#license>`_ allows
 using the library both in open-source and commercial projects.
 
+`Learn more... <contents.html>`_
+
 .. raw:: html
 
   <a class="btn btn-success" href="https://github.com/fmtlib/fmt">GitHub Repository</a>
 
   <div class="section footer">
-    <iframe src="http://ghbtns.com/github-btn.html?user=fmtlib&amp;repo=fmt&amp;type=watch&amp;count=true"
+    <iframe src="https://ghbtns.com/github-btn.html?user=fmtlib&amp;repo=fmt&amp;type=watch&amp;count=true"
             class="github-btn" width="100" height="20"></iframe>
   </div>

doc/syntax.rst

@@ -16,7 +16,7 @@ literal text, it can be escaped by doubling: ``{{`` and ``}}``.
 The grammar for a replacement field is as follows:
 
 .. productionlist:: sf
-   replacement_field: "{" [`arg_id`] [":" `format_spec`] "}"
+   replacement_field: "{" [`arg_id`] [":" (`format_spec` | `chrono_format_spec`)] "}"
    arg_id: `integer` | `identifier`
    integer: `digit`+
    digit: "0"..."9"
@@ -27,8 +27,8 @@ The grammar for a replacement field is as follows:
 In less formal terms, the replacement field can start with an *arg_id*
 that specifies the argument whose value is to be formatted and inserted into
 the output instead of the replacement field.
-The *arg_id* is optionally followed by a *format_spec*, which is preceded
-by a colon ``':'``.  These specify a non-default format for the replacement value.
+The *arg_id* is optionally followed by a *format_spec*, which is preceded by a
+colon ``':'``.  These specify a non-default format for the replacement value.
 
 See also the :ref:`formatspec` section.
 
@@ -75,14 +75,14 @@ although some of the formatting options are only supported by the numeric types.
 The general form of a *standard format specifier* is:
 
 .. productionlist:: sf
-   format_spec: [[`fill`]`align`][`sign`]["#"]["0"][`width`]["." `precision`][`type`]
+   format_spec: [[`fill`]`align`][`sign`]["#"]["0"][`width`]["." `precision`]["L"][`type`]
    fill: <a character other than '{' or '}'>
    align: "<" | ">" | "^"
    sign: "+" | "-" | " "
    width: `integer` | "{" [`arg_id`] "}"
    precision: `integer` | "{" [`arg_id`] "}"
-   type: `int_type` | "a" | "A" | "c" | "e" | "E" | "f" | "F" | "g" | "G" | "L" | "p" | "s"
-   int_type: "b" | "B" | "d" | "o" | "x" | "X"
+   type: "a" | "A" | "b" | "B" | "c" | "d" | "e" | "E" | "f" | "F" | "g" | "G" |
+       : "o" | "p" | "s" | "x" | "X"
 
 The *fill* character can be any Unicode code point other than ``'{'`` or
 ``'}'``. The presence of a fill character is signaled by the character following
@@ -112,18 +112,18 @@ meaning in this case.
 The *sign* option is only valid for number types, and can be one of the
 following:
 
-+---------+----------------------------------------------------------+
-| Option  | Meaning                                                  |
-+=========+==========================================================+
-| ``'+'`` | indicates that a sign should be used for both            |
-|         | positive as well as negative numbers.                    |
-+---------+----------------------------------------------------------+
-| ``'-'`` | indicates that a sign should be used only for negative   |
-|         | numbers (this is the default behavior).                  |
-+---------+----------------------------------------------------------+
-| space   | indicates that a leading space should be used on         |
-|         | positive numbers, and a minus sign on negative numbers.  |
-+---------+----------------------------------------------------------+
++---------+------------------------------------------------------------+
+| Option  | Meaning                                                    |
++=========+============================================================+
+| ``'+'`` | indicates that a sign should be used for both              |
+|         | nonnegative as well as negative numbers.                   |
++---------+------------------------------------------------------------+
+| ``'-'`` | indicates that a sign should be used only for negative     |
+|         | numbers (this is the default behavior).                    |
++---------+------------------------------------------------------------+
+| space   | indicates that a leading space should be used on           |
+|         | nonnegative numbers, and a minus sign on negative numbers. |
++---------+------------------------------------------------------------+
 
 The ``'#'`` option causes the "alternate form" to be used for the
 conversion.  The alternate form is defined differently for different
@@ -161,7 +161,11 @@ displayed after the decimal point for a floating-point value formatted with
 value formatted with ``'g'`` or ``'G'``.  For non-number types the field
 indicates the maximum field size - in other words, how many characters will be
 used from the field content. The *precision* is not allowed for integer,
-character, Boolean, and pointer values.
+character, Boolean, and pointer values. Note that a C string must be
+null-terminated even if precision is specified.
+
+The ``'L'`` option uses the current locale setting to insert the appropriate
+number separator characters. This option is only valid for numeric types.
 
 Finally, the *type* determines how the data should be presented.
 
@@ -200,6 +204,8 @@ The available integer presentation types are:
 |         | ``'#'`` option with this type adds the prefix ``"0B"``   |
 |         | to the output value.                                     |
 +---------+----------------------------------------------------------+
+| ``'c'`` | Character format. Outputs the number as a character.     |
++---------+----------------------------------------------------------+
 | ``'d'`` | Decimal integer. Outputs the number in base 10.          |
 +---------+----------------------------------------------------------+
 | ``'o'`` | Octal format. Outputs the number in base 8.              |
@@ -214,10 +220,6 @@ The available integer presentation types are:
 |         | ``'#'`` option with this type adds the prefix ``"0X"``   |
 |         | to the output value.                                     |
 +---------+----------------------------------------------------------+
-| ``'L'`` | Locale-specific format. This is the same as ``'d'``,     |
-|         | except that it uses the current locale setting to insert |
-|         | the appropriate number separator characters.             |
-+---------+----------------------------------------------------------+
 | none    | The same as ``'d'``.                                     |
 +---------+----------------------------------------------------------+
 
@@ -261,14 +263,8 @@ 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. |
 +---------+----------------------------------------------------------+
-| ``'L'`` | Locale-specific format. This is the same as ``'g'``,     |
-|         | except that it uses the current locale setting to insert |
-|         | the appropriate number separator characters.             |
-+---------+----------------------------------------------------------+
-| none    | Similar to ``'g'``, except that fixed-point notation,    |
-|         | when used, has at least one digit past the decimal       |
-|         | point. The default precision is as high as needed to     |
-|         | represent the particular value.                          |
+| none    | Similar to ``'g'``, except that the default precision is |
+|         | as high as needed to represent the particular value.     |
 +---------+----------------------------------------------------------+
 
 .. ifconfig:: False
@@ -303,6 +299,59 @@ The available presentation types for pointers are:
 | none    | The same as ``'p'``.                                     |
 +---------+----------------------------------------------------------+
 
+.. _chrono-specs:
+
+Chrono Format Specifications
+============================
+
+Format specifications for chrono types have the following syntax:
+
+.. productionlist:: sf
+   chrono_format_spec: [[`fill`]`align`][`width`]["." `precision`][`chrono_specs`]
+   chrono_specs: [`chrono_specs`] `conversion_spec` | `chrono_specs` `literal_char`
+   conversion_spec: "%" [`modifier`] `chrono_type`
+   literal_char: <a character other than '{', '}' or '%'>
+   modifier: "E" | "O"
+   chrono_type: "a" | "A" | "b" | "B" | "c" | "C" | "d" | "D" | "e" | "F" |
+              : "g" | "G" | "h" | "H" | "I" | "j" | "m" | "M" | "n" | "p" |
+              : "q" | "Q" | "r" | "R" | "S" | "t" | "T" | "u" | "U" | "V" |
+              : "w" | "W" | "x" | "X" | "y" | "Y" | "z" | "Z" | "%"
+
+Literal chars are copied unchanged to the output. Precision is valid only for
+``std::chrono::duration`` types with a floating-point representation type.
+
+The available presentation types (*chrono_type*) for chrono durations and time
+points are:
+
++---------+--------------------------------------------------------------------+
+| Type    | Meaning                                                            |
++=========+====================================================================+
+| ``'H'`` | The hour (24-hour clock) as a decimal number. If the result is a   |
+|         | single digit, it is prefixed with 0. The modified command ``%OH``  |
+|         | produces the locale's alternative representation.                  |
++---------+--------------------------------------------------------------------+
+| ``'M'`` | The minute as a decimal number. If the result is a single digit,   |
+|         | it is prefixed with 0. The modified command ``%OM`` produces the   |
+|         | locale's alternative representation.                               |
++---------+--------------------------------------------------------------------+
+| ``'S'`` | Seconds as a decimal number. If the number of seconds is less than |
+|         | 10, the result is prefixed with 0. If the precision of the input   |
+|         | cannot be exactly represented with seconds, then the format is a   |
+|         | decimal floating-point number with a fixed format and a precision  |
+|         | matching that of the precision of the input (or to a microseconds  |
+|         | precision if the conversion to floating-point decimal seconds      |
+|         | cannot be made within 18 fractional digits). The character for the |
+|         | decimal point is localized according to the locale. The modified   |
+|         | command ``%OS`` produces the locale's alternative representation.  |
++---------+--------------------------------------------------------------------+
+
+Specifiers that have a calendaric component such as `'d'` (the day of month)
+are valid only for ``std::tm`` and not durations or time points.
+
+``std::tm`` uses the system's `strftime
+<https://en.cppreference.com/w/cpp/chrono/c/strftime>`_ so refer to its
+documentation for details on supported conversion specifiers. 
+
 .. _formatexamples:
 
 Format Examples
@@ -391,7 +440,7 @@ Using type-specific formatting::
 
    auto t = tm();
    t.tm_year = 2010 - 1900;
-   t.tm_mon = 6;
+   t.tm_mon = 7;
    t.tm_mday = 4;
    t.tm_hour = 12;
    t.tm_min = 15;
@@ -401,7 +450,7 @@ Using type-specific formatting::
 
 Using the comma as a thousands separator::
 
-   #include <fmt/locale.h>
+   #include <fmt/format.h>
 
    auto s = fmt::format(std::locale("en_US.UTF-8"), "{:L}", 1234567890);
    // s == "1,234,567,890"

doc/usage.rst

@@ -15,7 +15,7 @@ Building the Library
 
 The included `CMake build script`__ can be used to build the fmt
 library on a wide range of platforms. CMake is freely available for
-download from http://www.cmake.org/download/.
+download from https://www.cmake.org/download/.
 
 __ https://github.com/fmtlib/fmt/blob/master/CMakeLists.txt
 
@@ -50,7 +50,15 @@ To build a `shared library`__ set the ``BUILD_SHARED_LIBS`` CMake variable to
 
   cmake -DBUILD_SHARED_LIBS=TRUE ...
 
-__ http://en.wikipedia.org/wiki/Library_%28computing%29#Shared_libraries
+__ https://en.wikipedia.org/wiki/Library_%28computing%29#Shared_libraries
+
+
+To build a `static library` with position independent code (required if the main
+consumer of the fmt library is a shared library i.e. a Python extension) set the
+``CMAKE_POSITION_INDEPENDENT_CODE`` CMake variable to ``TRUE``::
+
+  cmake -DCMAKE_POSITION_INDEPENDENT_CODE=TRUE ...
+
 
 Installing the Library
 ======================
@@ -83,6 +91,49 @@ 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)
 
+Usage with build2
+=================
+
+You can use `build2 <https://build2.org>`_, a dependency manager and a
+build-system combined, to use ``fmt``.
+
+Currently this package is available in these package repositories:
+
+- **https://cppget.org/fmt/** for released and published versions.
+- `The git repository with the sources of the build2 package of fmt <https://github.com/build2-packaging/fmt.git>`_
+  for unreleased or custom revisions of ``fmt``.
+
+**Usage:**
+
+- ``build2`` package name: ``fmt``
+- Library target name : ``lib{fmt}``
+
+For example, to make your ``build2`` project depend on ``fmt``:
+
+- Add one of the repositories to your configurations, or in your
+  ``repositories.manifest``, if not already there::
+
+    :
+    role: prerequisite
+    location: https://pkg.cppget.org/1/stable
+
+- Add this package as a dependency to your ``./manifest`` file
+  (example for ``v7.0.x``)::
+
+    depends: fmt ~7.0.0
+
+- Import the target and use it as a prerequisite to your own target
+  using `fmt` in the appropriate ``buildfile``::
+
+    import fmt = fmt%lib{fmt}
+    lib{mylib} : cxx{**} ... $fmt
+
+Then build your project as usual with `b` or `bdep update`.
+
+For ``build2`` newcomers or to get more details and use cases, you can read the
+``build2``
+`toolchain introduction <https://build2.org/build2-toolchain/doc/build2-toolchain-intro.xhtml>`_.
+
 Building the Documentation
 ==========================
 
@@ -130,6 +181,18 @@ The fmt port in vcpkg is kept up to date by Microsoft team members and community
 contributors. If the version is out of date, please `create an issue or pull
 request <https://github.com/Microsoft/vcpkg>`__ on the vcpkg repository.
 
+LHelper
+=======
+
+You can download and install fmt using
+`lhelper <https://github.com/franko/lhelper>`__ dependency manager::
+
+  lhelper activate <some-environment>
+  lhelper install fmt
+
+All the recipes for lhelper are kept in the
+`lhelper's recipe <https://github.com/franko/lhelper-recipes>`__ repository.
+
 Android NDK
 ===========
 
@@ -139,11 +202,11 @@ For an example of using fmt with Android NDK, see the
 `android-ndk-example <https://github.com/fmtlib/android-ndk-example>`_
 repository.
 
-__ https://github.com/fmtlib/fmt/blob/master/Android.mk
+__ https://github.com/fmtlib/fmt/blob/master/support/Android.mk
 
 Homebrew
 ========
 
-fmt can be installed on OS X using `Homebrew <http://brew.sh/>`_::
+fmt can be installed on OS X using `Homebrew <https://brew.sh/>`_::
 
   brew install fmt

include/fmt/args.h

@@ -0,0 +1,234 @@
+// Formatting library for C++ - dynamic format arguments
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_ARGS_H_
+#define FMT_ARGS_H_
+
+#include <functional>  // std::reference_wrapper
+#include <memory>      // std::unique_ptr
+#include <vector>
+
+#include "core.h"
+
+FMT_BEGIN_NAMESPACE
+
+namespace detail {
+
+template <typename T> struct is_reference_wrapper : std::false_type {};
+template <typename T>
+struct is_reference_wrapper<std::reference_wrapper<T>> : std::true_type {};
+
+template <typename T> const T& unwrap(const T& v) { return v; }
+template <typename T> const T& unwrap(const std::reference_wrapper<T>& v) {
+  return static_cast<const T&>(v);
+}
+
+class dynamic_arg_list {
+  // Workaround for clang's -Wweak-vtables. Unlike for regular classes, for
+  // templates it doesn't complain about inability to deduce single translation
+  // unit for placing vtable. So storage_node_base is made a fake template.
+  template <typename = void> struct node {
+    virtual ~node() = default;
+    std::unique_ptr<node<>> next;
+  };
+
+  template <typename T> struct typed_node : node<> {
+    T value;
+
+    template <typename Arg>
+    FMT_CONSTEXPR typed_node(const Arg& arg) : value(arg) {}
+
+    template <typename Char>
+    FMT_CONSTEXPR typed_node(const basic_string_view<Char>& arg)
+        : value(arg.data(), arg.size()) {}
+  };
+
+  std::unique_ptr<node<>> head_;
+
+ public:
+  template <typename T, typename Arg> const T& push(const Arg& arg) {
+    auto new_node = std::unique_ptr<typed_node<T>>(new typed_node<T>(arg));
+    auto& value = new_node->value;
+    new_node->next = std::move(head_);
+    head_ = std::move(new_node);
+    return value;
+  }
+};
+}  // namespace detail
+
+/**
+  \rst
+  A dynamic version of `fmt::format_arg_store`.
+  It's equipped with a storage to potentially temporary objects which lifetimes
+  could be shorter than the format arguments object.
+
+  It can be implicitly converted into `~fmt::basic_format_args` for passing
+  into type-erased formatting functions such as `~fmt::vformat`.
+  \endrst
+ */
+template <typename Context>
+class dynamic_format_arg_store
+#if FMT_GCC_VERSION && FMT_GCC_VERSION < 409
+    // Workaround a GCC template argument substitution bug.
+    : public basic_format_args<Context>
+#endif
+{
+ private:
+  using char_type = typename Context::char_type;
+
+  template <typename T> struct need_copy {
+    static constexpr detail::type mapped_type =
+        detail::mapped_type_constant<T, Context>::value;
+
+    enum {
+      value = !(detail::is_reference_wrapper<T>::value ||
+                std::is_same<T, basic_string_view<char_type>>::value ||
+                std::is_same<T, detail::std_string_view<char_type>>::value ||
+                (mapped_type != detail::type::cstring_type &&
+                 mapped_type != detail::type::string_type &&
+                 mapped_type != detail::type::custom_type))
+    };
+  };
+
+  template <typename T>
+  using stored_type = conditional_t<detail::is_string<T>::value &&
+                                        !has_formatter<T, Context>::value &&
+                                        !detail::is_reference_wrapper<T>::value,
+                                    std::basic_string<char_type>, T>;
+
+  // Storage of basic_format_arg must be contiguous.
+  std::vector<basic_format_arg<Context>> data_;
+  std::vector<detail::named_arg_info<char_type>> named_info_;
+
+  // Storage of arguments not fitting into basic_format_arg must grow
+  // without relocation because items in data_ refer to it.
+  detail::dynamic_arg_list dynamic_args_;
+
+  friend class basic_format_args<Context>;
+
+  unsigned long long get_types() const {
+    return detail::is_unpacked_bit | data_.size() |
+           (named_info_.empty()
+                ? 0ULL
+                : static_cast<unsigned long long>(detail::has_named_args_bit));
+  }
+
+  const basic_format_arg<Context>* data() const {
+    return named_info_.empty() ? data_.data() : data_.data() + 1;
+  }
+
+  template <typename T> void emplace_arg(const T& arg) {
+    data_.emplace_back(detail::make_arg<Context>(arg));
+  }
+
+  template <typename T>
+  void emplace_arg(const detail::named_arg<char_type, T>& arg) {
+    if (named_info_.empty()) {
+      constexpr const detail::named_arg_info<char_type>* zero_ptr{nullptr};
+      data_.insert(data_.begin(), {zero_ptr, 0});
+    }
+    data_.emplace_back(detail::make_arg<Context>(detail::unwrap(arg.value)));
+    auto pop_one = [](std::vector<basic_format_arg<Context>>* data) {
+      data->pop_back();
+    };
+    std::unique_ptr<std::vector<basic_format_arg<Context>>, decltype(pop_one)>
+        guard{&data_, pop_one};
+    named_info_.push_back({arg.name, static_cast<int>(data_.size() - 2u)});
+    data_[0].value_.named_args = {named_info_.data(), named_info_.size()};
+    guard.release();
+  }
+
+ public:
+  constexpr dynamic_format_arg_store() = default;
+
+  /**
+    \rst
+    Adds an argument into the dynamic store for later passing to a formatting
+    function.
+
+    Note that custom types and string types (but not string views) are copied
+    into the store dynamically allocating memory if necessary.
+
+    **Example**::
+
+      fmt::dynamic_format_arg_store<fmt::format_context> store;
+      store.push_back(42);
+      store.push_back("abc");
+      store.push_back(1.5f);
+      std::string result = fmt::vformat("{} and {} and {}", store);
+    \endrst
+  */
+  template <typename T> void push_back(const T& arg) {
+    if (detail::const_check(need_copy<T>::value))
+      emplace_arg(dynamic_args_.push<stored_type<T>>(arg));
+    else
+      emplace_arg(detail::unwrap(arg));
+  }
+
+  /**
+    \rst
+    Adds a reference to the argument into the dynamic store for later passing to
+    a formatting function.
+
+    **Example**::
+
+      fmt::dynamic_format_arg_store<fmt::format_context> store;
+      char band[] = "Rolling Stones";
+      store.push_back(std::cref(band));
+      band[9] = 'c'; // Changing str affects the output.
+      std::string result = fmt::vformat("{}", store);
+      // result == "Rolling Scones"
+    \endrst
+  */
+  template <typename T> void push_back(std::reference_wrapper<T> arg) {
+    static_assert(
+        need_copy<T>::value,
+        "objects of built-in types and string views are always copied");
+    emplace_arg(arg.get());
+  }
+
+  /**
+    Adds named argument into the dynamic store for later passing to a formatting
+    function. ``std::reference_wrapper`` is supported to avoid copying of the
+    argument. The name is always copied into the store.
+  */
+  template <typename T>
+  void push_back(const detail::named_arg<char_type, T>& arg) {
+    const char_type* arg_name =
+        dynamic_args_.push<std::basic_string<char_type>>(arg.name).c_str();
+    if (detail::const_check(need_copy<T>::value)) {
+      emplace_arg(
+          fmt::arg(arg_name, dynamic_args_.push<stored_type<T>>(arg.value)));
+    } else {
+      emplace_arg(fmt::arg(arg_name, arg.value));
+    }
+  }
+
+  /** Erase all elements from the store */
+  void clear() {
+    data_.clear();
+    named_info_.clear();
+    dynamic_args_ = detail::dynamic_arg_list();
+  }
+
+  /**
+    \rst
+    Reserves space to store at least *new_cap* arguments including
+    *new_cap_named* named arguments.
+    \endrst
+  */
+  void reserve(size_t new_cap, size_t new_cap_named) {
+    FMT_ASSERT(new_cap >= new_cap_named,
+               "Set of arguments includes set of named arguments");
+    data_.reserve(new_cap);
+    named_info_.reserve(new_cap_named);
+  }
+};
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_ARGS_H_

include/fmt/color.h

@@ -10,7 +10,15 @@
 
 #include "format.h"
 
+// __declspec(deprecated) is broken in some MSVC versions.
+#if FMT_MSC_VER
+#  define FMT_DEPRECATED_NONMSVC
+#else
+#  define FMT_DEPRECATED_NONMSVC FMT_DEPRECATED
+#endif
+
 FMT_BEGIN_NAMESPACE
+FMT_MODULE_EXPORT_BEGIN
 
 enum class color : uint32_t {
   alice_blue = 0xF0F8FF,               // rgb(240,248,255)
@@ -177,9 +185,13 @@ enum class terminal_color : uint8_t {
 
 enum class emphasis : uint8_t {
   bold = 1,
-  italic = 1 << 1,
-  underline = 1 << 2,
-  strikethrough = 1 << 3
+  faint = 1 << 1,
+  italic = 1 << 2,
+  underline = 1 << 3,
+  blink = 1 << 4,
+  reverse = 1 << 5,
+  conceal = 1 << 6,
+  strikethrough = 1 << 7,
 };
 
 // rgb is a struct for red, green and blue colors.
@@ -198,7 +210,7 @@ struct rgb {
   uint8_t b;
 };
 
-namespace detail {
+FMT_BEGIN_DETAIL_NAMESPACE
 
 // color is a struct of either a rgb color or a terminal color.
 struct color_type {
@@ -221,9 +233,10 @@ struct color_type {
     uint32_t rgb_color;
   } value;
 };
-}  // namespace detail
 
-// Experimental text formatting support.
+FMT_END_DETAIL_NAMESPACE
+
+/** A text style consisting of foreground and background colors and emphasis. */
 class text_style {
  public:
   FMT_CONSTEXPR text_style(emphasis em = emphasis()) FMT_NOEXCEPT
@@ -260,33 +273,14 @@ class text_style {
     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;
+  FMT_DEPRECATED_NONMSVC FMT_CONSTEXPR text_style& operator&=(
+      const text_style& rhs) {
+    return and_assign(rhs);
   }
 
-  friend FMT_CONSTEXPR text_style operator&(text_style lhs,
-                                            const text_style& rhs) {
-    return lhs &= rhs;
+  FMT_DEPRECATED_NONMSVC friend FMT_CONSTEXPR text_style
+  operator&(text_style lhs, const text_style& rhs) {
+    return lhs.and_assign(rhs);
   }
 
   FMT_CONSTEXPR bool has_foreground() const FMT_NOEXCEPT {
@@ -326,8 +320,34 @@ class text_style {
     }
   }
 
+  // DEPRECATED!
+  FMT_CONSTEXPR text_style& and_assign(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_DECL text_style fg(detail::color_type foreground)
       FMT_NOEXCEPT;
+
   friend FMT_CONSTEXPR_DECL text_style bg(detail::color_type background)
       FMT_NOEXCEPT;
 
@@ -338,19 +358,22 @@ class text_style {
   emphasis ems;
 };
 
-FMT_CONSTEXPR text_style fg(detail::color_type foreground) FMT_NOEXCEPT {
-  return text_style(/*is_foreground=*/true, foreground);
+/** Creates a text style from the foreground (text) color. */
+FMT_CONSTEXPR inline text_style fg(detail::color_type foreground) FMT_NOEXCEPT {
+  return text_style(true, foreground);
 }
 
-FMT_CONSTEXPR text_style bg(detail::color_type background) FMT_NOEXCEPT {
-  return text_style(/*is_foreground=*/false, background);
+/** Creates a text style from the background color. */
+FMT_CONSTEXPR inline text_style bg(detail::color_type background) FMT_NOEXCEPT {
+  return text_style(false, background);
 }
 
-FMT_CONSTEXPR text_style operator|(emphasis lhs, emphasis rhs) FMT_NOEXCEPT {
+FMT_CONSTEXPR inline text_style operator|(emphasis lhs,
+                                          emphasis rhs) FMT_NOEXCEPT {
   return text_style(lhs) | rhs;
 }
 
-namespace detail {
+FMT_BEGIN_DETAIL_NAMESPACE
 
 template <typename Char> struct ansi_color_escape {
   FMT_CONSTEXPR ansi_color_escape(detail::color_type text_color,
@@ -358,7 +381,7 @@ template <typename Char> struct ansi_color_escape {
     // If we have a terminal color, we need to output another escape code
     // sequence.
     if (!text_color.is_rgb) {
-      bool is_background = esc == detail::data::background_color;
+      bool is_background = esc == string_view("\x1b[48;2;");
       uint32_t value = text_color.value.term_color;
       // Background ASCII codes are the same as the foreground ones but with
       // 10 more.
@@ -390,16 +413,18 @@ template <typename Char> struct ansi_color_escape {
     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;
+    uint8_t em_codes[num_emphases] = {};
+    if (has_emphasis(em, emphasis::bold)) em_codes[0] = 1;
+    if (has_emphasis(em, emphasis::faint)) em_codes[1] = 2;
+    if (has_emphasis(em, emphasis::italic)) em_codes[2] = 3;
+    if (has_emphasis(em, emphasis::underline)) em_codes[3] = 4;
+    if (has_emphasis(em, emphasis::blink)) em_codes[4] = 5;
+    if (has_emphasis(em, emphasis::reverse)) em_codes[5] = 7;
+    if (has_emphasis(em, emphasis::conceal)) em_codes[6] = 8;
+    if (has_emphasis(em, emphasis::strikethrough)) em_codes[7] = 9;
 
     size_t index = 0;
-    for (int i = 0; i < 4; ++i) {
+    for (size_t i = 0; i < num_emphases; ++i) {
       if (!em_codes[i]) continue;
       buffer[index++] = static_cast<Char>('\x1b');
       buffer[index++] = static_cast<Char>('[');
@@ -411,12 +436,13 @@ template <typename Char> struct ansi_color_escape {
   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 {
+  FMT_CONSTEXPR_CHAR_TRAITS const Char* end() const FMT_NOEXCEPT {
     return buffer + std::char_traits<Char>::length(buffer);
   }
 
  private:
-  Char buffer[7u + 3u * 4u + 1u];
+  static constexpr size_t num_emphases = 8;
+  Char buffer[7u + 3u * num_emphases + 1u];
 
   static FMT_CONSTEXPR void to_esc(uint8_t c, Char* out,
                                    char delimiter) FMT_NOEXCEPT {
@@ -425,18 +451,22 @@ template <typename Char> struct ansi_color_escape {
     out[2] = static_cast<Char>('0' + c % 10);
     out[3] = static_cast<Char>(delimiter);
   }
+  static FMT_CONSTEXPR bool has_emphasis(emphasis em,
+                                         emphasis mask) FMT_NOEXCEPT {
+    return static_cast<uint8_t>(em) & static_cast<uint8_t>(mask);
+  }
 };
 
 template <typename Char>
 FMT_CONSTEXPR ansi_color_escape<Char> make_foreground_color(
     detail::color_type foreground) FMT_NOEXCEPT {
-  return ansi_color_escape<Char>(foreground, detail::data::foreground_color);
+  return ansi_color_escape<Char>(foreground, "\x1b[38;2;");
 }
 
 template <typename Char>
 FMT_CONSTEXPR ansi_color_escape<Char> make_background_color(
     detail::color_type background) FMT_NOEXCEPT {
-  return ansi_color_escape<Char>(background, detail::data::background_color);
+  return ansi_color_escape<Char>(background, "\x1b[48;2;");
 }
 
 template <typename Char>
@@ -455,24 +485,23 @@ inline void fputs<wchar_t>(const wchar_t* chars, FILE* stream) FMT_NOEXCEPT {
 }
 
 template <typename Char> inline void reset_color(FILE* stream) FMT_NOEXCEPT {
-  fputs(detail::data::reset_color, stream);
+  fputs("\x1b[0m", stream);
 }
 
 template <> inline void reset_color<wchar_t>(FILE* stream) FMT_NOEXCEPT {
-  fputs(detail::data::wreset_color, stream);
+  fputs(L"\x1b[0m", 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);
+inline void reset_color(buffer<Char>& buffer) FMT_NOEXCEPT {
+  auto reset_color = string_view("\x1b[0m");
+  buffer.append(reset_color.begin(), reset_color.end());
 }
 
 template <typename Char>
-void vformat_to(basic_memory_buffer<Char>& buf, const text_style& ts,
+void vformat_to(buffer<Char>& buf, const text_style& ts,
                 basic_string_view<Char> format_str,
-                basic_format_args<buffer_context<Char>> args) {
+                basic_format_args<buffer_context<type_identity_t<Char>>> args) {
   bool has_style = false;
   if (ts.has_emphasis()) {
     has_style = true;
@@ -489,14 +518,15 @@ void vformat_to(basic_memory_buffer<Char>& buf, const text_style& ts,
     auto background = detail::make_background_color<Char>(ts.get_background());
     buf.append(background.begin(), background.end());
   }
-  detail::vformat_to(buf, format_str, args);
+  detail::vformat_to(buf, format_str, args, {});
   if (has_style) detail::reset_color<Char>(buf);
 }
-}  // namespace detail
+
+FMT_END_DETAIL_NAMESPACE
 
 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) {
+            basic_format_args<buffer_context<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buf;
   detail::vformat_to(buf, ts, to_string_view(format), args);
   buf.push_back(Char(0));
@@ -504,28 +534,34 @@ void vprint(std::FILE* f, const text_style& ts, const S& format,
 }
 
 /**
+  \rst
   Formats a string and prints it to the specified file stream using ANSI
   escape sequences to specify text formatting.
-  Example:
+
+  **Example**::
+
     fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
                "Elapsed time: {0:.2f} seconds", 1.23);
+  \endrst
  */
 template <typename S, typename... Args,
           FMT_ENABLE_IF(detail::is_string<S>::value)>
 void print(std::FILE* f, const text_style& ts, const S& format_str,
            const Args&... args) {
-  detail::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));
+  vprint(f, ts, format_str,
+         fmt::make_args_checked<Args...>(format_str, args...));
 }
 
 /**
+  \rst
   Formats a string and prints it to stdout using ANSI escape sequences to
   specify text formatting.
-  Example:
+
+  **Example**::
+
     fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
                "Elapsed time: {0:.2f} seconds", 1.23);
+  \endrst
  */
 template <typename S, typename... Args,
           FMT_ENABLE_IF(detail::is_string<S>::value)>
@@ -557,10 +593,46 @@ inline std::basic_string<Char> vformat(
 template <typename S, typename... Args, typename Char = char_t<S>>
 inline std::basic_string<Char> format(const text_style& ts, const S& format_str,
                                       const Args&... args) {
-  return vformat(ts, to_string_view(format_str),
-                 detail::make_args_checked<Args...>(format_str, args...));
+  return fmt::vformat(ts, to_string_view(format_str),
+                      fmt::make_args_checked<Args...>(format_str, args...));
 }
 
+/**
+  Formats a string with the given text_style and writes the output to ``out``.
+ */
+template <typename OutputIt, typename Char,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value)>
+OutputIt vformat_to(
+    OutputIt out, const text_style& ts, basic_string_view<Char> format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  auto&& buf = detail::get_buffer<Char>(out);
+  detail::vformat_to(buf, ts, format_str, args);
+  return detail::get_iterator(buf);
+}
+
+/**
+  \rst
+  Formats arguments with the given text_style, writes the result to the output
+  iterator ``out`` and returns the iterator past the end of the output range.
+
+  **Example**::
+
+    std::vector<char> out;
+    fmt::format_to(std::back_inserter(out),
+                   fmt::emphasis::bold | fg(fmt::color::red), "{}", 42);
+  \endrst
+*/
+template <typename OutputIt, typename S, typename... Args,
+          bool enable = detail::is_output_iterator<OutputIt, char_t<S>>::value&&
+              detail::is_string<S>::value>
+inline auto format_to(OutputIt out, const text_style& ts, const S& format_str,
+                      Args&&... args) ->
+    typename std::enable_if<enable, OutputIt>::type {
+  return vformat_to(out, ts, to_string_view(format_str),
+                    fmt::make_args_checked<Args...>(format_str, args...));
+}
+
+FMT_MODULE_EXPORT_END
 FMT_END_NAMESPACE
 
 #endif  // FMT_COLOR_H_

include/fmt/locale.h

@@ -1,78 +1,2 @@
-// 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 detail {
-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<type_identity_t<Char>>> args) {
-  using af = arg_formatter<typename buffer_context<Char>::iterator, Char>;
-  return vformat_to<af>(std::back_inserter(buf), to_string_view(format_str),
-                        args, detail::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<type_identity_t<Char>>> args) {
-  basic_memory_buffer<Char> buffer;
-  detail::vformat_to(loc, buffer, format_str, args);
-  return fmt::to_string(buffer);
-}
-}  // namespace detail
-
-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<type_identity_t<Char>>> args) {
-  return detail::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 detail::vformat(
-      loc, to_string_view(format_str),
-      detail::make_args_checked<Args...>(format_str, args...));
-}
-
-template <typename S, typename OutputIt, typename... Args,
-          typename Char = enable_if_t<
-              detail::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<type_identity_t<OutputIt>, Char> args) {
-  using af = detail::arg_formatter<OutputIt, Char>;
-  return vformat_to<af>(out, to_string_view(format_str), args,
-                        detail::locale_ref(loc));
-}
-
-template <typename OutputIt, typename S, typename... Args,
-          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt>::value&&
-                            detail::is_string<S>::value)>
-inline OutputIt format_to(OutputIt out, const std::locale& loc,
-                          const S& format_str, Args&&... args) {
-  detail::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 "xchar.h"
+#warning fmt/locale.h is deprecated, include fmt/format.h or fmt/xchar.h instead

include/fmt/os.h

@@ -8,16 +8,12 @@
 #ifndef FMT_OS_H_
 #define FMT_OS_H_
 
-#if defined(__MINGW32__) || defined(__CYGWIN__)
-// Workaround MinGW bug https://sourceforge.net/p/mingw/bugs/2024/.
-#  undef __STRICT_ANSI__
-#endif
-
 #include <cerrno>
-#include <clocale>  // for locale_t
+#include <clocale>  // locale_t
 #include <cstddef>
 #include <cstdio>
-#include <cstdlib>  // for strtod_l
+#include <cstdlib>       // strtod_l
+#include <system_error>  // std::system_error
 
 #if defined __APPLE__ || defined(__FreeBSD__)
 #  include <xlocale.h>  // for LC_NUMERIC_MASK on OS X
@@ -25,16 +21,20 @@
 
 #include "format.h"
 
+#ifndef FMT_USE_FCNTL
 // UWP doesn't provide _pipe.
-#if FMT_HAS_INCLUDE("winapifamily.h")
-#  include <winapifamily.h>
-#endif
-#if FMT_HAS_INCLUDE("fcntl.h") && \
-    (!defined(WINAPI_FAMILY) || (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP))
-#  include <fcntl.h>  // for O_RDONLY
-#  define FMT_USE_FCNTL 1
-#else
-#  define FMT_USE_FCNTL 0
+#  if FMT_HAS_INCLUDE("winapifamily.h")
+#    include <winapifamily.h>
+#  endif
+#  if (FMT_HAS_INCLUDE(<fcntl.h>) || defined(__APPLE__) || \
+       defined(__linux__)) &&                              \
+      (!defined(WINAPI_FAMILY) ||                          \
+       (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP))
+#    include <fcntl.h>  // for O_RDONLY
+#    define FMT_USE_FCNTL 1
+#  else
+#    define FMT_USE_FCNTL 0
+#  endif
 #endif
 
 #ifndef FMT_POSIX
@@ -73,6 +73,7 @@
 #define FMT_RETRY(result, expression) FMT_RETRY_VAL(result, expression, -1)
 
 FMT_BEGIN_NAMESPACE
+FMT_MODULE_EXPORT_BEGIN
 
 /**
   \rst
@@ -121,19 +122,28 @@ template <typename Char> class basic_cstring_view {
 using cstring_view = basic_cstring_view<char>;
 using wcstring_view = basic_cstring_view<wchar_t>;
 
-// An error code.
-class error_code {
- private:
-  int value_;
+template <typename Char> struct formatter<std::error_code, Char> {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
 
- public:
-  explicit error_code(int value = 0) FMT_NOEXCEPT : value_(value) {}
-
-  int get() const FMT_NOEXCEPT { return value_; }
+  template <typename FormatContext>
+  FMT_CONSTEXPR auto format(const std::error_code& ec, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+    out = detail::write_bytes(out, ec.category().name(),
+                              basic_format_specs<Char>());
+    out = detail::write<Char>(out, Char(':'));
+    out = detail::write<Char>(out, ec.value());
+    return out;
+  }
 };
 
 #ifdef _WIN32
-namespace detail {
+FMT_API const std::error_category& system_category() FMT_NOEXCEPT;
+
+FMT_BEGIN_DETAIL_NAMESPACE
 // A converter from UTF-16 to UTF-8.
 // It is only provided for Windows since other systems support UTF-8 natively.
 class utf16_to_utf8 {
@@ -142,7 +152,7 @@ class utf16_to_utf8 {
 
  public:
   utf16_to_utf8() {}
-  FMT_API explicit utf16_to_utf8(wstring_view s);
+  FMT_API explicit utf16_to_utf8(basic_string_view<wchar_t> s);
   operator string_view() const { return string_view(&buffer_[0], size()); }
   size_t size() const { return buffer_.size() - 1; }
   const char* c_str() const { return &buffer_[0]; }
@@ -151,59 +161,68 @@ class utf16_to_utf8 {
   // Performs conversion returning a system error code instead of
   // throwing exception on conversion error. This method may still throw
   // in case of memory allocation error.
-  FMT_API int convert(wstring_view s);
+  FMT_API int convert(basic_string_view<wchar_t> s);
 };
 
 FMT_API void format_windows_error(buffer<char>& out, int error_code,
-                                  string_view message) FMT_NOEXCEPT;
-}  // namespace detail
+                                  const char* message) FMT_NOEXCEPT;
+FMT_END_DETAIL_NAMESPACE
 
-/** A Windows error. */
-class windows_error : public system_error {
- private:
-  FMT_API void init(int error_code, string_view format_str, format_args args);
+FMT_API std::system_error vwindows_error(int error_code, string_view format_str,
+                                         format_args args);
 
- public:
-  /**
-   \rst
-   Constructs a :class:`fmt::windows_error` object with the description
-   of the form
+/**
+ \rst
+ Constructs a :class:`std::system_error` object with the description
+ of the form
 
-   .. parsed-literal::
-     *<message>*: *<system-message>*
+ .. parsed-literal::
+   *<message>*: *<system-message>*
 
-   where *<message>* is the formatted message and *<system-message>* is the
-   system message corresponding to the error code.
-   *error_code* is a Windows error code as given by ``GetLastError``.
-   If *error_code* is not a valid error code such as -1, the system message
-   will look like "error -1".
+ where *<message>* is the formatted message and *<system-message>* is the
+ system message corresponding to the error code.
+ *error_code* is a Windows error code as given by ``GetLastError``.
+ If *error_code* is not a valid error code such as -1, the system message
+ will look like "error -1".
 
-   **Example**::
+ **Example**::
 
-     // This throws a windows_error with the description
-     //   cannot open file 'madeup': The system cannot find the file specified.
-     // or similar (system message may vary).
-     const char *filename = "madeup";
-     LPOFSTRUCT of = LPOFSTRUCT();
-     HFILE file = OpenFile(filename, &of, OF_READ);
-     if (file == HFILE_ERROR) {
-       throw fmt::windows_error(GetLastError(),
-                                "cannot open file '{}'", filename);
-     }
-   \endrst
-  */
-  template <typename... Args>
-  windows_error(int error_code, string_view message, const Args&... args) {
-    init(error_code, message, make_format_args(args...));
-  }
-};
+   // This throws a system_error with the description
+   //   cannot open file 'madeup': The system cannot find the file specified.
+   // or similar (system message may vary).
+   const char *filename = "madeup";
+   LPOFSTRUCT of = LPOFSTRUCT();
+   HFILE file = OpenFile(filename, &of, OF_READ);
+   if (file == HFILE_ERROR) {
+     throw fmt::windows_error(GetLastError(),
+                              "cannot open file '{}'", filename);
+   }
+ \endrst
+*/
+template <typename... Args>
+std::system_error windows_error(int error_code, string_view message,
+                                const Args&... args) {
+  return vwindows_error(error_code, message, fmt::make_format_args(args...));
+}
 
 // Reports a Windows error without throwing an exception.
 // Can be used to report errors from destructors.
 FMT_API void report_windows_error(int error_code,
-                                  string_view message) FMT_NOEXCEPT;
+                                  const char* message) FMT_NOEXCEPT;
+#else
+inline const std::error_category& system_category() FMT_NOEXCEPT {
+  return std::system_category();
+}
 #endif  // _WIN32
 
+// std::system is not available on some platforms such as iOS (#2248).
+#ifdef __OSX__
+template <typename S, typename... Args, typename Char = char_t<S>>
+void say(const S& format_str, Args&&... args) {
+  std::system(format("say \"{}\"", format(format_str, args...)).c_str());
+}
+#endif
+
 // A buffered file.
 class buffered_file {
  private:
@@ -254,7 +273,7 @@ class buffered_file {
 
   template <typename... Args>
   inline void print(string_view format_str, const Args&... args) {
-    vprint(format_str, make_format_args(args...));
+    vprint(format_str, fmt::make_format_args(args...));
   }
 };
 
@@ -278,7 +297,9 @@ class file {
     RDONLY = FMT_POSIX(O_RDONLY),  // Open for reading only.
     WRONLY = FMT_POSIX(O_WRONLY),  // Open for writing only.
     RDWR = FMT_POSIX(O_RDWR),      // Open for reading and writing.
-    CREATE = FMT_POSIX(O_CREAT)    // Create if the file doesn't exist.
+    CREATE = FMT_POSIX(O_CREAT),   // Create if the file doesn't exist.
+    APPEND = FMT_POSIX(O_APPEND),  // Open in append mode.
+    TRUNC = FMT_POSIX(O_TRUNC)     // Truncate the content of the file.
   };
 
   // Constructs a file object which doesn't represent any file.
@@ -293,7 +314,8 @@ class file {
 
   file(file&& other) FMT_NOEXCEPT : fd_(other.fd_) { other.fd_ = -1; }
 
-  file& operator=(file&& other) FMT_NOEXCEPT {
+  // Move assignment is not noexcept because close may throw.
+  file& operator=(file&& other) {
     close();
     fd_ = other.fd_;
     other.fd_ = -1;
@@ -329,7 +351,7 @@ 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, std::error_code& ec) FMT_NOEXCEPT;
 
   // Creates a pipe setting up read_end and write_end file objects for reading
   // and writing respectively.
@@ -343,62 +365,116 @@ class file {
 // Returns the memory page size.
 long getpagesize();
 
-class direct_buffered_file;
+FMT_BEGIN_DETAIL_NAMESPACE
 
-template <typename S, typename... Args>
-void print(direct_buffered_file& f, const S& format_str,
-           const Args&... args);
+struct buffer_size {
+  buffer_size() = default;
+  size_t value = 0;
+  buffer_size operator=(size_t val) const {
+    auto bs = buffer_size();
+    bs.value = val;
+    return bs;
+  }
+};
 
-// A buffered file with a direct buffer access and no synchronization.
-class direct_buffered_file {
+struct ostream_params {
+  int oflag = file::WRONLY | file::CREATE | file::TRUNC;
+  size_t buffer_size = BUFSIZ > 32768 ? BUFSIZ : 32768;
+
+  ostream_params() {}
+
+  template <typename... T>
+  ostream_params(T... params, int new_oflag) : ostream_params(params...) {
+    oflag = new_oflag;
+  }
+
+  template <typename... T>
+  ostream_params(T... params, detail::buffer_size bs)
+      : ostream_params(params...) {
+    this->buffer_size = bs.value;
+  }
+
+// Intel has a bug that results in failure to deduce a constructor
+// for empty parameter packs.
+#  if defined(__INTEL_COMPILER) && __INTEL_COMPILER < 2000
+  ostream_params(int new_oflag) : oflag(new_oflag) {}
+  ostream_params(detail::buffer_size bs) : buffer_size(bs.value) {}
+#  endif
+};
+
+FMT_END_DETAIL_NAMESPACE
+
+// Added {} below to work around default constructor error known to
+// occur in Xcode versions 7.2.1 and 8.2.1.
+constexpr detail::buffer_size buffer_size{};
+
+/** A fast output stream which is not thread-safe. */
+class FMT_API ostream final : private detail::buffer<char> {
  private:
   file file_;
 
-  enum { buffer_size = 4096 };
-  char buffer_[buffer_size];
-  int pos_;
+  void grow(size_t) override;
 
-  void flush() {
-    if (pos_ == 0) return;
-    file_.write(buffer_, pos_);
-    pos_ = 0;
+  ostream(cstring_view path, const detail::ostream_params& params)
+      : file_(path, params.oflag) {
+    set(new char[params.buffer_size], params.buffer_size);
   }
 
-  int free_capacity() const { return buffer_size - pos_; }
-
  public:
-  direct_buffered_file(cstring_view path, int oflag)
-    : file_(path, oflag), pos_(0) {}
-
-  ~direct_buffered_file() {
-    flush();
+  ostream(ostream&& other)
+      : detail::buffer<char>(other.data(), other.size(), other.capacity()),
+        file_(std::move(other.file_)) {
+    other.clear();
+    other.set(nullptr, 0);
   }
+  ~ostream() {
+    flush();
+    delete[] data();
+  }
+
+  void flush() {
+    if (size() == 0) return;
+    file_.write(data(), size());
+    clear();
+  }
+
+  template <typename... T>
+  friend ostream output_file(cstring_view path, T... params);
 
   void close() {
     flush();
     file_.close();
   }
 
-  template <typename S, typename... Args>
-  friend void print(direct_buffered_file& f, const S& format_str,
-                    const Args&... args) {
-    // We could avoid double buffering.
-    auto buf = fmt::memory_buffer();
-    fmt::format_to(std::back_inserter(buf), format_str, args...);
-    auto remaining_pos = 0;
-    auto remaining_size = buf.size();
-    while (remaining_size > detail::to_unsigned(f.free_capacity())) {
-      auto size = f.free_capacity();
-      memcpy(f.buffer_ + f.pos_, buf.data() + remaining_pos, size);
-      f.pos_ += size;
-      f.flush();
-      remaining_pos += size;
-      remaining_size -= size;
-    }
-    memcpy(f.buffer_ + f.pos_, buf.data() + remaining_pos, remaining_size);
-    f.pos_ += static_cast<int>(remaining_size);
+  /**
+    Formats ``args`` according to specifications in ``fmt`` and writes the
+    output to the file.
+   */
+  template <typename... T> void print(format_string<T...> fmt, T&&... args) {
+    vformat_to(detail::buffer_appender<char>(*this), fmt,
+               fmt::make_format_args(args...));
   }
 };
+
+/**
+  \rst
+  Opens a file for writing. Supported parameters passed in *params*:
+
+  * ``<integer>``: Flags passed to `open
+    <https://pubs.opengroup.org/onlinepubs/007904875/functions/open.html>`_
+    (``file::WRONLY | file::CREATE`` by default)
+  * ``buffer_size=<integer>``: Output buffer size
+
+  **Example**::
+
+    auto out = fmt::output_file("guide.txt");
+    out.print("Don't {}", "Panic");
+  \endrst
+ */
+template <typename... T>
+inline ostream output_file(cstring_view path, T... params) {
+  return {path, detail::ostream_params(params...)};
+}
 #endif  // FMT_USE_FCNTL
 
 #ifdef FMT_LOCALE
@@ -436,7 +512,7 @@ class locale {
 
   // Converts string to floating-point number and advances str past the end
   // of the parsed input.
-  double strtod(const char*& str) const {
+  FMT_DEPRECATED double strtod(const char*& str) const {
     char* end = nullptr;
     double result = strtod_l(str, &end, locale_);
     str = end;
@@ -445,6 +521,7 @@ class locale {
 };
 using Locale FMT_DEPRECATED_ALIAS = locale;
 #endif  // FMT_LOCALE
+FMT_MODULE_EXPORT_END
 FMT_END_NAMESPACE
 
 #endif  // FMT_OS_H_

include/fmt/ostream.h

@@ -14,71 +14,44 @@
 
 FMT_BEGIN_NAMESPACE
 
-template <typename Char> class basic_printf_parse_context;
 template <typename OutputIt, typename Char> class basic_printf_context;
 
 namespace detail {
 
-template <class Char> class formatbuf : public std::basic_streambuf<Char> {
- private:
-  using int_type = typename std::basic_streambuf<Char>::int_type;
-  using traits_type = typename std::basic_streambuf<Char>::traits_type;
-
-  buffer<Char>& buffer_;
-
- public:
-  formatbuf(buffer<Char>& buf) : buffer_(buf) {}
-
- protected:
-  // The put-area is actually always empty. This makes the implementation
-  // simpler and has the advantage that the streambuf and the buffer are always
-  // in sync and sputc never writes into uninitialized memory. The obvious
-  // disadvantage is that each call to sputc always results in a (virtual) call
-  // to overflow. There is no disadvantage here for sputn since this always
-  // results in a call to xsputn.
-
-  int_type overflow(int_type ch = traits_type::eof()) FMT_OVERRIDE {
-    if (!traits_type::eq_int_type(ch, traits_type::eof()))
-      buffer_.push_back(static_cast<Char>(ch));
-    return ch;
-  }
-
-  std::streamsize xsputn(const Char* s, std::streamsize count) FMT_OVERRIDE {
-    buffer_.append(s, s + count);
-    return count;
-  }
-};
-
-template <typename Char> struct test_stream : std::basic_ostream<Char> {
- private:
-  // Hide all operator<< from std::basic_ostream<Char>.
-  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<<.
+template <typename T, typename Char, typename Enable = void>
+class is_streamable {
  private:
   template <typename U>
-  static bool_constant<!std::is_same<decltype(std::declval<test_stream<Char>&>()
-                                              << std::declval<U>()),
-                                     void_t<>>::value>
-  test(int);
+  static auto test(int)
+      -> bool_constant<sizeof(std::declval<std::basic_ostream<Char>&>()
+                              << std::declval<U>()) != 0>;
 
-  template <typename> static std::false_type test(...);
+  template <typename> static auto test(...) -> std::false_type;
 
   using result = decltype(test<T>(0));
 
  public:
+  is_streamable() = default;
+
   static const bool value = result::value;
 };
 
+// Formatting of built-in types and arrays is intentionally disabled because
+// it's handled by standard (non-ostream) formatters.
+template <typename T, typename Char>
+struct is_streamable<
+    T, Char,
+    enable_if_t<
+        std::is_arithmetic<T>::value || std::is_array<T>::value ||
+        std::is_pointer<T>::value || std::is_same<T, char8_type>::value ||
+        std::is_same<T, std::basic_string<Char>>::value ||
+        std::is_same<T, std_string_view<Char>>::value ||
+        (std::is_convertible<T, int>::value && !std::is_enum<T>::value)>>
+    : std::false_type {};
+
 // Write the content of buf to os.
+// It is a separate function rather than a part of vprint to simplify testing.
 template <typename Char>
 void write_buffer(std::basic_ostream<Char>& os, buffer<Char>& buf) {
   const Char* buf_data = buf.data();
@@ -96,53 +69,47 @@ void write_buffer(std::basic_ostream<Char>& os, buffer<Char>& buf) {
 template <typename Char, typename T>
 void format_value(buffer<Char>& buf, const T& value,
                   locale_ref loc = locale_ref()) {
-  formatbuf<Char> format_buf(buf);
-  std::basic_ostream<Char> output(&format_buf);
+  auto&& format_buf = formatbuf<std::basic_streambuf<Char>>(buf);
+  auto&& output = std::basic_ostream<Char>(&format_buf);
 #if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
   if (loc) output.imbue(loc.get<std::locale>());
 #endif
   output << value;
   output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
-  buf.resize(buf.size());
+  buf.try_resize(buf.size());
 }
 
 // Formats an object of type T that has an overloaded ostream operator<<.
 template <typename T, typename Char>
 struct fallback_formatter<T, Char, enable_if_t<is_streamable<T, Char>::value>>
     : private formatter<basic_string_view<Char>, Char> {
-  FMT_CONSTEXPR auto parse(basic_format_parse_context<Char>& ctx)
-      -> decltype(ctx.begin()) {
-    return formatter<basic_string_view<Char>, Char>::parse(ctx);
-  }
-  template <typename ParseCtx,
-            FMT_ENABLE_IF(std::is_same<
-                          ParseCtx, basic_printf_parse_context<Char>>::value)>
-  auto parse(ParseCtx& ctx) -> decltype(ctx.begin()) {
-    return ctx.begin();
-  }
+  using formatter<basic_string_view<Char>, Char>::parse;
 
   template <typename OutputIt>
   auto format(const T& value, basic_format_context<OutputIt, Char>& ctx)
       -> OutputIt {
-    basic_memory_buffer<Char> buffer;
+    auto buffer = basic_memory_buffer<Char>();
     format_value(buffer, value, ctx.locale());
-    basic_string_view<Char> str(buffer.data(), buffer.size());
-    return formatter<basic_string_view<Char>, Char>::format(str, ctx);
+    return formatter<basic_string_view<Char>, Char>::format(
+        {buffer.data(), buffer.size()}, ctx);
   }
+
+  // DEPRECATED!
   template <typename OutputIt>
   auto format(const T& value, basic_printf_context<OutputIt, Char>& ctx)
       -> OutputIt {
-    basic_memory_buffer<Char> buffer;
+    auto buffer = basic_memory_buffer<Char>();
     format_value(buffer, value, ctx.locale());
     return std::copy(buffer.begin(), buffer.end(), ctx.out());
   }
 };
 }  // namespace detail
 
+FMT_MODULE_EXPORT
 template <typename Char>
 void vprint(std::basic_ostream<Char>& os, basic_string_view<Char> format_str,
             basic_format_args<buffer_context<type_identity_t<Char>>> args) {
-  basic_memory_buffer<Char> buffer;
+  auto buffer = basic_memory_buffer<Char>();
   detail::vformat_to(buffer, format_str, args);
   detail::write_buffer(os, buffer);
 }
@@ -156,11 +123,12 @@ void vprint(std::basic_ostream<Char>& os, basic_string_view<Char> format_str,
     fmt::print(cerr, "Don't {}!", "panic");
   \endrst
  */
+FMT_MODULE_EXPORT
 template <typename S, typename... Args,
           typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>>
 void print(std::basic_ostream<Char>& os, const S& format_str, Args&&... args) {
   vprint(os, to_string_view(format_str),
-         detail::make_args_checked<Args...>(format_str, args...));
+         fmt::make_args_checked<Args...>(format_str, args...));
 }
 FMT_END_NAMESPACE
 

include/fmt/posix.h

@@ -1,2 +0,0 @@
-#include "os.h"
-#warning "fmt/posix.h is deprecated; use fmt/os.h instead"

include/fmt/printf.h

@@ -10,11 +10,54 @@
 
 #include <algorithm>  // std::max
 #include <limits>     // std::numeric_limits
+#include <ostream>
 
-#include "ostream.h"
+#include "format.h"
 
 FMT_BEGIN_NAMESPACE
-namespace detail {
+FMT_MODULE_EXPORT_BEGIN
+
+template <typename T> struct printf_formatter { printf_formatter() = delete; };
+
+template <typename Char>
+class basic_printf_parse_context : public basic_format_parse_context<Char> {
+  using basic_format_parse_context<Char>::basic_format_parse_context;
+};
+
+template <typename OutputIt, typename Char> class basic_printf_context {
+ private:
+  OutputIt out_;
+  basic_format_args<basic_printf_context> args_;
+
+ public:
+  using char_type = Char;
+  using format_arg = basic_format_arg<basic_printf_context>;
+  using parse_context_type = basic_printf_parse_context<Char>;
+  template <typename T> using formatter_type = printf_formatter<T>;
+
+  /**
+    \rst
+    Constructs a ``printf_context`` object. References to the arguments are
+    stored in the context object so make sure they have appropriate lifetimes.
+    \endrst
+   */
+  basic_printf_context(OutputIt out,
+                       basic_format_args<basic_printf_context> args)
+      : out_(out), args_(args) {}
+
+  OutputIt out() { return out_; }
+  void advance_to(OutputIt it) { out_ = it; }
+
+  detail::locale_ref locale() { return {}; }
+
+  format_arg arg(int id) const { return args_.get(id); }
+
+  FMT_CONSTEXPR void on_error(const char* message) {
+    detail::error_handler().on_error(message);
+  }
+};
+
+FMT_BEGIN_DETAIL_NAMESPACE
 
 // Checks if a value fits in int - used to avoid warnings about comparing
 // signed and unsigned integers.
@@ -178,81 +221,38 @@ template <typename Char> class printf_width_handler {
   }
 };
 
-template <typename Char, typename Context>
-void vprintf(buffer<Char>& buf, basic_string_view<Char> format,
-             basic_format_args<Context> args) {
-  Context(std::back_inserter(buf), format, args).format();
-}
-}  // namespace detail
-
-// For printing into memory_buffer.
-template <typename Char, typename Context>
-FMT_DEPRECATED void printf(detail::buffer<Char>& buf,
-                           basic_string_view<Char> format,
-                           basic_format_args<Context> args) {
-  return detail::vprintf(buf, format, args);
-}
-using detail::vprintf;
-
-template <typename Char>
-class basic_printf_parse_context : public basic_format_parse_context<Char> {
-  using basic_format_parse_context<Char>::basic_format_parse_context;
-};
-template <typename OutputIt, typename Char> class basic_printf_context;
-
-/**
-  \rst
-  The ``printf`` argument formatter.
-  \endrst
- */
+// The ``printf`` argument formatter.
 template <typename OutputIt, typename Char>
-class printf_arg_formatter : public detail::arg_formatter_base<OutputIt, Char> {
- public:
-  using iterator = OutputIt;
-
+class printf_arg_formatter : public arg_formatter<Char> {
  private:
-  using char_type = Char;
-  using base = detail::arg_formatter_base<OutputIt, Char>;
+  using base = arg_formatter<Char>;
   using context_type = basic_printf_context<OutputIt, Char>;
+  using format_specs = basic_format_specs<Char>;
 
   context_type& context_;
 
-  void write_null_pointer(char) {
-    this->specs()->type = 0;
-    this->write("(nil)");
-  }
-
-  void write_null_pointer(wchar_t) {
-    this->specs()->type = 0;
-    this->write(L"(nil)");
+  OutputIt write_null_pointer(bool is_string = false) {
+    auto s = this->specs;
+    s.type = presentation_type::none;
+    return write_bytes(this->out, is_string ? "(null)" : "(nil)", s);
   }
 
  public:
-  using format_specs = typename base::format_specs;
+  printf_arg_formatter(OutputIt iter, format_specs& s, context_type& ctx)
+      : base{iter, s, locale_ref()}, context_(ctx) {}
 
-  /**
-    \rst
-    Constructs an argument formatter object.
-    *buffer* is a reference to the output buffer and *specs* contains format
-    specifier information for standard argument types.
-    \endrst
-   */
-  printf_arg_formatter(iterator iter, format_specs& specs, context_type& ctx)
-      : base(iter, &specs, detail::locale_ref()), context_(ctx) {}
+  OutputIt operator()(monostate value) { return base::operator()(value); }
 
-  template <typename T, FMT_ENABLE_IF(fmt::detail::is_integral<T>::value)>
-  iterator operator()(T value) {
-    // MSVC2013 fails to compile separate overloads for bool and char_type so
-    // use std::is_same instead.
-    if (std::is_same<T, bool>::value) {
-      format_specs& fmt_specs = *this->specs();
-      if (fmt_specs.type != 's') return base::operator()(value ? 1 : 0);
-      fmt_specs.type = 0;
-      this->write(value != 0);
-    } else if (std::is_same<T, char_type>::value) {
-      format_specs& fmt_specs = *this->specs();
-      if (fmt_specs.type && fmt_specs.type != 'c')
+  template <typename T, FMT_ENABLE_IF(detail::is_integral<T>::value)>
+  OutputIt operator()(T value) {
+    // MSVC2013 fails to compile separate overloads for bool and Char so use
+    // std::is_same instead.
+    if (std::is_same<T, Char>::value) {
+      format_specs fmt_specs = this->specs;
+      if (fmt_specs.type != presentation_type::none &&
+          fmt_specs.type != presentation_type::chr) {
         return (*this)(static_cast<int>(value));
+      }
       fmt_specs.sign = sign::none;
       fmt_specs.alt = false;
       fmt_specs.fill[0] = ' ';  // Ignore '0' flag for char types.
@@ -260,138 +260,49 @@ class printf_arg_formatter : public detail::arg_formatter_base<OutputIt, Char> {
       // ignored for non-numeric types
       if (fmt_specs.align == align::none || fmt_specs.align == align::numeric)
         fmt_specs.align = align::right;
-      return base::operator()(value);
-    } else {
-      return base::operator()(value);
+      return write<Char>(this->out, static_cast<Char>(value), fmt_specs);
     }
-    return this->out();
+    return base::operator()(value);
   }
 
   template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
-  iterator operator()(T value) {
+  OutputIt operator()(T value) {
     return base::operator()(value);
   }
 
   /** Formats a null-terminated C string. */
-  iterator operator()(const char* value) {
-    if (value)
-      base::operator()(value);
-    else if (this->specs()->type == 'p')
-      write_null_pointer(char_type());
-    else
-      this->write("(null)");
-    return this->out();
+  OutputIt operator()(const char* value) {
+    if (value) return base::operator()(value);
+    return write_null_pointer(this->specs.type != presentation_type::pointer);
   }
 
   /** Formats a null-terminated wide C string. */
-  iterator operator()(const wchar_t* value) {
-    if (value)
-      base::operator()(value);
-    else if (this->specs()->type == 'p')
-      write_null_pointer(char_type());
-    else
-      this->write(L"(null)");
-    return this->out();
+  OutputIt operator()(const wchar_t* value) {
+    if (value) return base::operator()(value);
+    return write_null_pointer(this->specs.type != presentation_type::pointer);
   }
 
-  iterator operator()(basic_string_view<char_type> value) {
+  OutputIt operator()(basic_string_view<Char> value) {
     return base::operator()(value);
   }
 
-  iterator operator()(monostate value) { return base::operator()(value); }
-
   /** Formats a pointer. */
-  iterator operator()(const void* value) {
-    if (value) return base::operator()(value);
-    this->specs()->type = 0;
-    write_null_pointer(char_type());
-    return this->out();
+  OutputIt operator()(const void* value) {
+    return value ? base::operator()(value) : write_null_pointer();
   }
 
   /** Formats an argument of a custom (user-defined) type. */
-  iterator operator()(typename basic_format_arg<context_type>::handle handle) {
-    handle.format(context_.parse_context(), context_);
-    return this->out();
+  OutputIt operator()(typename basic_format_arg<context_type>::handle handle) {
+    auto parse_ctx =
+        basic_printf_parse_context<Char>(basic_string_view<Char>());
+    handle.format(parse_ctx, context_);
+    return this->out;
   }
 };
 
-template <typename T> struct printf_formatter {
-  printf_formatter() = delete;
-
-  template <typename ParseContext>
-  auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
-    return ctx.begin();
-  }
-
-  template <typename FormatContext>
-  auto format(const T& value, FormatContext& ctx) -> decltype(ctx.out()) {
-    detail::format_value(detail::get_container(ctx.out()), value);
-    return ctx.out();
-  }
-};
-
-/**
- This template formats data and writes the output through an output iterator.
- */
-template <typename OutputIt, typename Char> class basic_printf_context {
- public:
-  /** The character type for the output. */
-  using char_type = Char;
-  using iterator = OutputIt;
-  using format_arg = basic_format_arg<basic_printf_context>;
-  using parse_context_type = basic_printf_parse_context<Char>;
-  template <typename T> using formatter_type = printf_formatter<T>;
-
- private:
-  using format_specs = basic_format_specs<char_type>;
-
-  OutputIt out_;
-  basic_format_args<basic_printf_context> args_;
-  parse_context_type parse_ctx_;
-
-  static void parse_flags(format_specs& specs, const Char*& it,
-                          const Char* end);
-
-  // Returns the argument with specified index or, if arg_index is -1, the next
-  // argument.
-  format_arg get_arg(int arg_index = -1);
-
-  // Parses argument index, flags and width and returns the argument index.
-  int parse_header(const Char*& it, const Char* end, format_specs& specs);
-
- public:
-  /**
-   \rst
-   Constructs a ``printf_context`` object. References to the arguments are
-   stored in the context object so make sure they have appropriate lifetimes.
-   \endrst
-   */
-  basic_printf_context(OutputIt out, basic_string_view<char_type> format_str,
-                       basic_format_args<basic_printf_context> args)
-      : out_(out), args_(args), parse_ctx_(format_str) {}
-
-  OutputIt out() { return out_; }
-  void advance_to(OutputIt it) { out_ = it; }
-
-  detail::locale_ref locale() { return {}; }
-
-  format_arg arg(int id) const { return args_.get(id); }
-
-  parse_context_type& parse_context() { return parse_ctx_; }
-
-  FMT_CONSTEXPR void on_error(const char* message) {
-    parse_ctx_.on_error(message);
-  }
-
-  /** Formats stored arguments and writes the output to the range. */
-  template <typename ArgFormatter = printf_arg_formatter<OutputIt, Char>>
-  OutputIt format();
-};
-
-template <typename OutputIt, typename Char>
-void basic_printf_context<OutputIt, Char>::parse_flags(format_specs& specs,
-                                                       const Char*& it,
-                                                       const Char* end) {
+template <typename Char>
+void parse_flags(basic_format_specs<Char>& specs, const Char*& it,
+                 const Char* end) {
   for (; it != end; ++it) {
     switch (*it) {
     case '-':
@@ -417,35 +328,24 @@ void basic_printf_context<OutputIt, Char>::parse_flags(format_specs& specs,
   }
 }
 
-template <typename OutputIt, typename Char>
-typename basic_printf_context<OutputIt, Char>::format_arg
-basic_printf_context<OutputIt, Char>::get_arg(int arg_index) {
-  if (arg_index < 0)
-    arg_index = parse_ctx_.next_arg_id();
-  else
-    parse_ctx_.check_arg_id(--arg_index);
-  return detail::get_arg(*this, arg_index);
-}
-
-template <typename OutputIt, typename Char>
-int basic_printf_context<OutputIt, Char>::parse_header(const Char*& it,
-                                                       const Char* end,
-                                                       format_specs& specs) {
+template <typename Char, typename GetArg>
+int parse_header(const Char*& it, const Char* end,
+                 basic_format_specs<Char>& specs, GetArg get_arg) {
   int arg_index = -1;
-  char_type c = *it;
+  Char c = *it;
   if (c >= '0' && c <= '9') {
     // Parse an argument index (if followed by '$') or a width possibly
     // preceded with '0' flag(s).
-    detail::error_handler eh;
-    int value = parse_nonnegative_int(it, end, eh);
+    int value = parse_nonnegative_int(it, end, -1);
     if (it != end && *it == '$') {  // value is an argument index
       ++it;
-      arg_index = value;
+      arg_index = value != -1 ? value : max_value<int>();
     } else {
       if (c == '0') specs.fill[0] = '0';
       if (value != 0) {
         // Nonzero value means that we parsed width and don't need to
         // parse it or flags again, so return now.
+        if (value == -1) FMT_THROW(format_error("number is too big"));
         specs.width = value;
         return arg_index;
       }
@@ -455,58 +355,76 @@ int basic_printf_context<OutputIt, Char>::parse_header(const Char*& it,
   // Parse width.
   if (it != end) {
     if (*it >= '0' && *it <= '9') {
-      detail::error_handler eh;
-      specs.width = parse_nonnegative_int(it, end, eh);
+      specs.width = parse_nonnegative_int(it, end, -1);
+      if (specs.width == -1) FMT_THROW(format_error("number is too big"));
     } else if (*it == '*') {
       ++it;
       specs.width = static_cast<int>(visit_format_arg(
-          detail::printf_width_handler<char_type>(specs), get_arg()));
+          detail::printf_width_handler<Char>(specs), get_arg(-1)));
     }
   }
   return arg_index;
 }
 
-template <typename OutputIt, typename Char>
-template <typename ArgFormatter>
-OutputIt basic_printf_context<OutputIt, Char>::format() {
-  auto out = this->out();
-  const Char* start = parse_ctx_.begin();
-  const Char* end = parse_ctx_.end();
+template <typename Char, typename Context>
+void vprintf(buffer<Char>& buf, basic_string_view<Char> format,
+             basic_format_args<Context> args) {
+  using OutputIt = buffer_appender<Char>;
+  auto out = OutputIt(buf);
+  auto context = basic_printf_context<OutputIt, Char>(out, args);
+  auto parse_ctx = basic_printf_parse_context<Char>(format);
+
+  // Returns the argument with specified index or, if arg_index is -1, the next
+  // argument.
+  auto get_arg = [&](int arg_index) {
+    if (arg_index < 0)
+      arg_index = parse_ctx.next_arg_id();
+    else
+      parse_ctx.check_arg_id(--arg_index);
+    return detail::get_arg(context, arg_index);
+  };
+
+  const Char* start = parse_ctx.begin();
+  const Char* end = parse_ctx.end();
   auto it = start;
   while (it != end) {
-    char_type c = *it++;
-    if (c != '%') continue;
+    if (!detail::find<false, Char>(it, end, '%', it)) {
+      it = end;  // detail::find leaves it == nullptr if it doesn't find '%'
+      break;
+    }
+    Char c = *it++;
     if (it != end && *it == c) {
-      out = std::copy(start, it, out);
+      out = detail::write(
+          out, basic_string_view<Char>(start, detail::to_unsigned(it - start)));
       start = ++it;
       continue;
     }
-    out = std::copy(start, it - 1, out);
+    out = detail::write(out, basic_string_view<Char>(
+                                 start, detail::to_unsigned(it - 1 - start)));
 
-    format_specs specs;
+    basic_format_specs<Char> specs;
     specs.align = align::right;
 
     // Parse argument index, flags and width.
-    int arg_index = parse_header(it, end, specs);
-    if (arg_index == 0) on_error("argument not found");
+    int arg_index = parse_header(it, end, specs, get_arg);
+    if (arg_index == 0) parse_ctx.on_error("argument not found");
 
     // Parse precision.
     if (it != end && *it == '.') {
       ++it;
       c = it != end ? *it : 0;
       if ('0' <= c && c <= '9') {
-        detail::error_handler eh;
-        specs.precision = parse_nonnegative_int(it, end, eh);
+        specs.precision = parse_nonnegative_int(it, end, 0);
       } else if (c == '*') {
         ++it;
         specs.precision = static_cast<int>(
-            visit_format_arg(detail::printf_precision_handler(), get_arg()));
+            visit_format_arg(detail::printf_precision_handler(), get_arg(-1)));
       } else {
         specs.precision = 0;
       }
     }
 
-    format_arg arg = get_arg(arg_index);
+    auto arg = get_arg(arg_index);
     // For d, i, o, u, x, and X conversion specifiers, if a precision is
     // specified, the '0' flag is ignored
     if (specs.precision >= 0 && arg.is_integral())
@@ -516,9 +434,10 @@ OutputIt basic_printf_context<OutputIt, Char>::format() {
       auto str = visit_format_arg(detail::get_cstring<Char>(), arg);
       auto str_end = str + specs.precision;
       auto nul = std::find(str, str_end, Char());
-      arg = detail::make_arg<basic_printf_context>(basic_string_view<Char>(
-          str,
-          detail::to_unsigned(nul != str_end ? nul - str : specs.precision)));
+      arg = detail::make_arg<basic_printf_context<OutputIt, Char>>(
+          basic_string_view<Char>(
+              str, detail::to_unsigned(nul != str_end ? nul - str
+                                                      : specs.precision)));
     }
     if (specs.alt && visit_format_arg(detail::is_zero_int(), arg))
       specs.alt = false;
@@ -532,7 +451,7 @@ OutputIt basic_printf_context<OutputIt, Char>::format() {
 
     // Parse length and convert the argument to the required type.
     c = it != end ? *it++ : 0;
-    char_type t = it != end ? *it : 0;
+    Char t = it != end ? *it : 0;
     using detail::convert_arg;
     switch (c) {
     case 'h':
@@ -573,32 +492,38 @@ OutputIt basic_printf_context<OutputIt, Char>::format() {
 
     // Parse type.
     if (it == end) FMT_THROW(format_error("invalid format string"));
-    specs.type = static_cast<char>(*it++);
+    char type = static_cast<char>(*it++);
     if (arg.is_integral()) {
       // Normalize type.
-      switch (specs.type) {
+      switch (type) {
       case 'i':
       case 'u':
-        specs.type = 'd';
+        type = 'd';
         break;
       case 'c':
-        visit_format_arg(detail::char_converter<basic_printf_context>(arg),
-                         arg);
+        visit_format_arg(
+            detail::char_converter<basic_printf_context<OutputIt, Char>>(arg),
+            arg);
         break;
       }
     }
+    specs.type = parse_presentation_type(type);
+    if (specs.type == presentation_type::none)
+      parse_ctx.on_error("invalid type specifier");
 
     start = it;
 
     // Format argument.
-    out = visit_format_arg(ArgFormatter(out, specs, *this), arg);
+    out = visit_format_arg(
+        detail::printf_arg_formatter<OutputIt, Char>(out, specs, context), arg);
   }
-  return std::copy(start, it, out);
+  detail::write(out, basic_string_view<Char>(start, to_unsigned(it - start)));
 }
+FMT_END_DETAIL_NAMESPACE
 
 template <typename Char>
 using basic_printf_context_t =
-    basic_printf_context<std::back_insert_iterator<detail::buffer<Char>>, Char>;
+    basic_printf_context<detail::buffer_appender<Char>, Char>;
 
 using printf_context = basic_printf_context_t<char>;
 using wprintf_context = basic_printf_context_t<wchar_t>;
@@ -612,9 +537,9 @@ using wprintf_args = basic_format_args<wprintf_context>;
   arguments and can be implicitly converted to `~fmt::printf_args`.
   \endrst
  */
-template <typename... Args>
-inline format_arg_store<printf_context, Args...> make_printf_args(
-    const Args&... args) {
+template <typename... T>
+inline auto make_printf_args(const T&... args)
+    -> format_arg_store<printf_context, T...> {
   return {args...};
 }
 
@@ -624,18 +549,19 @@ inline format_arg_store<printf_context, Args...> make_printf_args(
   arguments and can be implicitly converted to `~fmt::wprintf_args`.
   \endrst
  */
-template <typename... Args>
-inline format_arg_store<wprintf_context, Args...> make_wprintf_args(
-    const Args&... args) {
+template <typename... T>
+inline auto make_wprintf_args(const T&... args)
+    -> format_arg_store<wprintf_context, T...> {
   return {args...};
 }
 
 template <typename S, typename Char = char_t<S>>
-inline std::basic_string<Char> vsprintf(
-    const S& format,
-    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
+inline auto vsprintf(
+    const S& fmt,
+    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args)
+    -> std::basic_string<Char> {
   basic_memory_buffer<Char> buffer;
-  vprintf(buffer, to_string_view(format), args);
+  vprintf(buffer, to_string_view(fmt), args);
   return to_string(buffer);
 }
 
@@ -648,19 +574,20 @@ inline std::basic_string<Char> vsprintf(
     std::string message = fmt::sprintf("The answer is %d", 42);
   \endrst
 */
-template <typename S, typename... Args,
+template <typename S, typename... T,
           typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>>
-inline std::basic_string<Char> sprintf(const S& format, const Args&... args) {
+inline auto sprintf(const S& fmt, const T&... args) -> std::basic_string<Char> {
   using context = basic_printf_context_t<Char>;
-  return vsprintf(to_string_view(format), make_format_args<context>(args...));
+  return vsprintf(to_string_view(fmt), fmt::make_format_args<context>(args...));
 }
 
 template <typename S, typename Char = char_t<S>>
-inline int vfprintf(
-    std::FILE* f, const S& format,
-    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
+inline auto vfprintf(
+    std::FILE* f, const S& fmt,
+    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args)
+    -> int {
   basic_memory_buffer<Char> buffer;
-  vprintf(buffer, to_string_view(format), args);
+  vprintf(buffer, to_string_view(fmt), args);
   size_t size = buffer.size();
   return std::fwrite(buffer.data(), sizeof(Char), size, f) < size
              ? -1
@@ -676,19 +603,19 @@ inline int vfprintf(
     fmt::fprintf(stderr, "Don't %s!", "panic");
   \endrst
  */
-template <typename S, typename... Args,
-          typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>>
-inline int fprintf(std::FILE* f, const S& format, const Args&... args) {
+template <typename S, typename... T, typename Char = char_t<S>>
+inline auto fprintf(std::FILE* f, const S& fmt, const T&... args) -> int {
   using context = basic_printf_context_t<Char>;
-  return vfprintf(f, to_string_view(format),
-                  make_format_args<context>(args...));
+  return vfprintf(f, to_string_view(fmt),
+                  fmt::make_format_args<context>(args...));
 }
 
 template <typename S, typename Char = char_t<S>>
-inline int vprintf(
-    const S& format,
-    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
-  return vfprintf(stdout, to_string_view(format), args);
+inline auto vprintf(
+    const S& fmt,
+    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args)
+    -> int {
+  return vfprintf(stdout, to_string_view(fmt), args);
 }
 
 /**
@@ -700,52 +627,31 @@ inline int vprintf(
     fmt::printf("Elapsed time: %.2f seconds", 1.23);
   \endrst
  */
-template <typename S, typename... Args,
-          FMT_ENABLE_IF(detail::is_string<S>::value)>
-inline int printf(const S& format_str, const Args&... args) {
-  using context = basic_printf_context_t<char_t<S>>;
-  return vprintf(to_string_view(format_str),
-                 make_format_args<context>(args...));
+template <typename S, typename... T, FMT_ENABLE_IF(detail::is_string<S>::value)>
+inline auto printf(const S& fmt, const T&... args) -> int {
+  return vprintf(
+      to_string_view(fmt),
+      fmt::make_format_args<basic_printf_context_t<char_t<S>>>(args...));
 }
 
 template <typename S, typename Char = char_t<S>>
-inline int vfprintf(
-    std::basic_ostream<Char>& os, const S& format,
-    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
+FMT_DEPRECATED auto vfprintf(
+    std::basic_ostream<Char>& os, const S& fmt,
+    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args)
+    -> int {
   basic_memory_buffer<Char> buffer;
-  vprintf(buffer, to_string_view(format), args);
-  detail::write_buffer(os, buffer);
+  vprintf(buffer, to_string_view(fmt), args);
+  os.write(buffer.data(), static_cast<std::streamsize>(buffer.size()));
   return static_cast<int>(buffer.size());
 }
-
-/** Formats arguments and writes the output to the range. */
-template <typename ArgFormatter, typename Char,
-          typename Context =
-              basic_printf_context<typename ArgFormatter::iterator, Char>>
-typename ArgFormatter::iterator vprintf(
-    detail::buffer<Char>& out, basic_string_view<Char> format_str,
-    basic_format_args<type_identity_t<Context>> args) {
-  typename ArgFormatter::iterator iter(out);
-  Context(iter, format_str, args).template format<ArgFormatter>();
-  return iter;
+template <typename S, typename... T, typename Char = char_t<S>>
+FMT_DEPRECATED auto fprintf(std::basic_ostream<Char>& os, const S& fmt,
+                            const T&... args) -> int {
+  return vfprintf(os, to_string_view(fmt),
+                  fmt::make_format_args<basic_printf_context_t<Char>>(args...));
 }
 
-/**
-  \rst
-  Prints formatted data to the stream *os*.
-
-  **Example**::
-
-    fmt::fprintf(cerr, "Don't %s!", "panic");
-  \endrst
- */
-template <typename S, typename... Args, typename Char = char_t<S>>
-inline int fprintf(std::basic_ostream<Char>& os, const S& format_str,
-                   const Args&... args) {
-  using context = basic_printf_context_t<Char>;
-  return vfprintf(os, to_string_view(format_str),
-                  make_format_args<context>(args...));
-}
+FMT_MODULE_EXPORT_END
 FMT_END_NAMESPACE
 
 #endif  // FMT_PRINTF_H_

include/fmt/ranges.h

@@ -13,47 +13,13 @@
 #define FMT_RANGES_H_
 
 #include <initializer_list>
+#include <tuple>
 #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
-#endif
-
 FMT_BEGIN_NAMESPACE
 
-template <typename Char> struct formatting_base {
-  template <typename ParseContext>
-  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
-    return ctx.begin();
-  }
-};
-
-template <typename Char, typename Enable = void>
-struct formatting_range : formatting_base<Char> {
-  static FMT_CONSTEXPR_DECL const size_t range_length_limit =
-      FMT_RANGE_OUTPUT_LENGTH_LIMIT;  // output only up to N items from the
-                                      // range.
-  Char prefix;
-  Char delimiter;
-  Char postfix;
-  formatting_range() : prefix('{'), delimiter(','), postfix('}') {}
-  static FMT_CONSTEXPR_DECL const bool add_delimiter_spaces = true;
-  static FMT_CONSTEXPR_DECL const bool add_prepostfix_space = false;
-};
-
-template <typename Char, typename Enable = void>
-struct formatting_tuple : formatting_base<Char> {
-  Char prefix;
-  Char delimiter;
-  Char postfix;
-  formatting_tuple() : prefix('('), delimiter(','), postfix(')') {}
-  static FMT_CONSTEXPR_DECL const bool add_delimiter_spaces = true;
-  static FMT_CONSTEXPR_DECL const bool add_prepostfix_space = false;
-};
-
 namespace detail {
 
 template <typename RangeT, typename OutputIterator>
@@ -75,8 +41,14 @@ OutputIterator copy(char ch, OutputIterator out) {
   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 OutputIterator>
+OutputIterator copy(wchar_t ch, OutputIterator out) {
+  *out++ = ch;
+  return out;
+}
+
+// Returns true if T has a std::string-like interface, like std::string_view.
+template <typename T> class is_std_string_like {
   template <typename U>
   static auto check(U* p)
       -> decltype((void)p->find('a'), p->length(), (void)p->data(), int());
@@ -84,26 +56,118 @@ template <typename T> class is_like_std_string {
 
  public:
   static FMT_CONSTEXPR_DECL const bool value =
-      is_string<T>::value || !std::is_void<decltype(check<T>(nullptr))>::value;
+      is_string<T>::value ||
+      std::is_convertible<T, std_string_view<char>>::value ||
+      !std::is_void<decltype(check<T>(nullptr))>::value;
 };
 
 template <typename Char>
-struct is_like_std_string<fmt::basic_string_view<Char>> : std::true_type {};
+struct is_std_string_like<fmt::basic_string_view<Char>> : std::true_type {};
+
+template <typename T> class is_map {
+  template <typename U> static auto check(U*) -> typename U::mapped_type;
+  template <typename> static void check(...);
+
+ public:
+#ifdef FMT_FORMAT_MAP_AS_LIST
+  static FMT_CONSTEXPR_DECL const bool value = false;
+#else
+  static FMT_CONSTEXPR_DECL const bool value =
+      !std::is_void<decltype(check<T>(nullptr))>::value;
+#endif
+};
+
+template <typename T> class is_set {
+  template <typename U> static auto check(U*) -> typename U::key_type;
+  template <typename> static void check(...);
+
+ public:
+#ifdef FMT_FORMAT_SET_AS_LIST
+  static FMT_CONSTEXPR_DECL const bool value = false;
+#else
+  static FMT_CONSTEXPR_DECL const bool value =
+      !std::is_void<decltype(check<T>(nullptr))>::value && !is_map<T>::value;
+#endif
+};
 
 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
+
+#  define FMT_DECLTYPE_RETURN(val)  \
+    ->decltype(val) { return val; } \
+    static_assert(                  \
+        true, "")  // This makes it so that a semicolon is required after the
+                   // macro, which helps clang-format handle the formatting.
+
+// C array overload
+template <typename T, std::size_t N>
+auto range_begin(const T (&arr)[N]) -> const T* {
+  return arr;
+}
+template <typename T, std::size_t N>
+auto range_end(const T (&arr)[N]) -> const T* {
+  return arr + N;
+}
+
+template <typename T, typename Enable = void>
+struct has_member_fn_begin_end_t : std::false_type {};
+
 template <typename T>
-struct is_range_<
-    T, conditional_t<false,
-                     conditional_helper<decltype(std::declval<T>().begin()),
-                                        decltype(std::declval<T>().end())>,
-                     void>> : std::true_type {};
+struct has_member_fn_begin_end_t<T, void_t<decltype(std::declval<T>().begin()),
+                                           decltype(std::declval<T>().end())>>
+    : std::true_type {};
+
+// Member function overload
+template <typename T>
+auto range_begin(T&& rng) FMT_DECLTYPE_RETURN(static_cast<T&&>(rng).begin());
+template <typename T>
+auto range_end(T&& rng) FMT_DECLTYPE_RETURN(static_cast<T&&>(rng).end());
+
+// ADL overload. Only participates in overload resolution if member functions
+// are not found.
+template <typename T>
+auto range_begin(T&& rng)
+    -> enable_if_t<!has_member_fn_begin_end_t<T&&>::value,
+                   decltype(begin(static_cast<T&&>(rng)))> {
+  return begin(static_cast<T&&>(rng));
+}
+template <typename T>
+auto range_end(T&& rng) -> enable_if_t<!has_member_fn_begin_end_t<T&&>::value,
+                                       decltype(end(static_cast<T&&>(rng)))> {
+  return end(static_cast<T&&>(rng));
+}
+
+template <typename T, typename Enable = void>
+struct has_const_begin_end : std::false_type {};
+template <typename T, typename Enable = void>
+struct has_mutable_begin_end : std::false_type {};
+
+template <typename T>
+struct has_const_begin_end<
+    T,
+    void_t<
+        decltype(detail::range_begin(std::declval<const remove_cvref_t<T>&>())),
+        decltype(detail::range_end(std::declval<const remove_cvref_t<T>&>()))>>
+    : std::true_type {};
+
+template <typename T>
+struct has_mutable_begin_end<
+    T, void_t<decltype(detail::range_begin(std::declval<T>())),
+              decltype(detail::range_end(std::declval<T>())),
+              enable_if_t<std::is_copy_constructible<T>::value>>>
+    : std::true_type {};
+
+template <typename T>
+struct is_range_<T, void>
+    : std::integral_constant<bool, (has_const_begin_end<T>::value ||
+                                    has_mutable_begin_end<T>::value)> {};
+#  undef FMT_DECLTYPE_RETURN
 #endif
 
-/// tuple_size and tuple_element check.
+// tuple_size and tuple_element check.
 template <typename T> class is_tuple_like_ {
   template <typename U>
   static auto check(U* p) -> decltype(std::tuple_size<U>::value, int());
@@ -157,30 +221,320 @@ template <class Tuple, class F> void for_each(Tuple&& tup, F&& f) {
   for_each(indexes, std::forward<Tuple>(tup), std::forward<F>(f));
 }
 
-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 Range>
+using value_type =
+    remove_cvref_t<decltype(*detail::range_begin(std::declval<Range>()))>;
+
+template <typename OutputIt> OutputIt write_delimiter(OutputIt out) {
+  *out++ = ',';
+  *out++ = ' ';
+  return out;
 }
 
-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 ? " \"{}\"" : "\"{}\"";
+struct singleton {
+  unsigned char upper;
+  unsigned char lower_count;
+};
+
+inline auto is_printable(uint16_t x, const singleton* singletons,
+                         size_t singletons_size,
+                         const unsigned char* singleton_lowers,
+                         const unsigned char* normal, size_t normal_size)
+    -> bool {
+  auto upper = x >> 8;
+  auto lower_start = 0;
+  for (size_t i = 0; i < singletons_size; ++i) {
+    auto s = singletons[i];
+    auto lower_end = lower_start + s.lower_count;
+    if (upper < s.upper) break;
+    if (upper == s.upper) {
+      for (auto j = lower_start; j < lower_end; ++j) {
+        if (singleton_lowers[j] == (x & 0xff)) return false;
+      }
+    }
+    lower_start = lower_end;
+  }
+
+  auto xsigned = static_cast<int>(x);
+  auto current = true;
+  for (size_t i = 0; i < normal_size; ++i) {
+    auto v = static_cast<int>(normal[i]);
+    auto len = (v & 0x80) != 0 ? (v & 0x7f) << 8 | normal[++i] : v;
+    xsigned -= len;
+    if (xsigned < 0) break;
+    current = !current;
+  }
+  return current;
 }
 
-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"\"{}\"";
+// Returns true iff the code point cp is printable.
+// This code is generated by support/printable.py.
+inline auto is_printable(uint32_t cp) -> bool {
+  static constexpr singleton singletons0[] = {
+      {0x00, 1},  {0x03, 5},  {0x05, 6},  {0x06, 3},  {0x07, 6},  {0x08, 8},
+      {0x09, 17}, {0x0a, 28}, {0x0b, 25}, {0x0c, 20}, {0x0d, 16}, {0x0e, 13},
+      {0x0f, 4},  {0x10, 3},  {0x12, 18}, {0x13, 9},  {0x16, 1},  {0x17, 5},
+      {0x18, 2},  {0x19, 3},  {0x1a, 7},  {0x1c, 2},  {0x1d, 1},  {0x1f, 22},
+      {0x20, 3},  {0x2b, 3},  {0x2c, 2},  {0x2d, 11}, {0x2e, 1},  {0x30, 3},
+      {0x31, 2},  {0x32, 1},  {0xa7, 2},  {0xa9, 2},  {0xaa, 4},  {0xab, 8},
+      {0xfa, 2},  {0xfb, 5},  {0xfd, 4},  {0xfe, 3},  {0xff, 9},
+  };
+  static constexpr unsigned char singletons0_lower[] = {
+      0xad, 0x78, 0x79, 0x8b, 0x8d, 0xa2, 0x30, 0x57, 0x58, 0x8b, 0x8c, 0x90,
+      0x1c, 0x1d, 0xdd, 0x0e, 0x0f, 0x4b, 0x4c, 0xfb, 0xfc, 0x2e, 0x2f, 0x3f,
+      0x5c, 0x5d, 0x5f, 0xb5, 0xe2, 0x84, 0x8d, 0x8e, 0x91, 0x92, 0xa9, 0xb1,
+      0xba, 0xbb, 0xc5, 0xc6, 0xc9, 0xca, 0xde, 0xe4, 0xe5, 0xff, 0x00, 0x04,
+      0x11, 0x12, 0x29, 0x31, 0x34, 0x37, 0x3a, 0x3b, 0x3d, 0x49, 0x4a, 0x5d,
+      0x84, 0x8e, 0x92, 0xa9, 0xb1, 0xb4, 0xba, 0xbb, 0xc6, 0xca, 0xce, 0xcf,
+      0xe4, 0xe5, 0x00, 0x04, 0x0d, 0x0e, 0x11, 0x12, 0x29, 0x31, 0x34, 0x3a,
+      0x3b, 0x45, 0x46, 0x49, 0x4a, 0x5e, 0x64, 0x65, 0x84, 0x91, 0x9b, 0x9d,
+      0xc9, 0xce, 0xcf, 0x0d, 0x11, 0x29, 0x45, 0x49, 0x57, 0x64, 0x65, 0x8d,
+      0x91, 0xa9, 0xb4, 0xba, 0xbb, 0xc5, 0xc9, 0xdf, 0xe4, 0xe5, 0xf0, 0x0d,
+      0x11, 0x45, 0x49, 0x64, 0x65, 0x80, 0x84, 0xb2, 0xbc, 0xbe, 0xbf, 0xd5,
+      0xd7, 0xf0, 0xf1, 0x83, 0x85, 0x8b, 0xa4, 0xa6, 0xbe, 0xbf, 0xc5, 0xc7,
+      0xce, 0xcf, 0xda, 0xdb, 0x48, 0x98, 0xbd, 0xcd, 0xc6, 0xce, 0xcf, 0x49,
+      0x4e, 0x4f, 0x57, 0x59, 0x5e, 0x5f, 0x89, 0x8e, 0x8f, 0xb1, 0xb6, 0xb7,
+      0xbf, 0xc1, 0xc6, 0xc7, 0xd7, 0x11, 0x16, 0x17, 0x5b, 0x5c, 0xf6, 0xf7,
+      0xfe, 0xff, 0x80, 0x0d, 0x6d, 0x71, 0xde, 0xdf, 0x0e, 0x0f, 0x1f, 0x6e,
+      0x6f, 0x1c, 0x1d, 0x5f, 0x7d, 0x7e, 0xae, 0xaf, 0xbb, 0xbc, 0xfa, 0x16,
+      0x17, 0x1e, 0x1f, 0x46, 0x47, 0x4e, 0x4f, 0x58, 0x5a, 0x5c, 0x5e, 0x7e,
+      0x7f, 0xb5, 0xc5, 0xd4, 0xd5, 0xdc, 0xf0, 0xf1, 0xf5, 0x72, 0x73, 0x8f,
+      0x74, 0x75, 0x96, 0x2f, 0x5f, 0x26, 0x2e, 0x2f, 0xa7, 0xaf, 0xb7, 0xbf,
+      0xc7, 0xcf, 0xd7, 0xdf, 0x9a, 0x40, 0x97, 0x98, 0x30, 0x8f, 0x1f, 0xc0,
+      0xc1, 0xce, 0xff, 0x4e, 0x4f, 0x5a, 0x5b, 0x07, 0x08, 0x0f, 0x10, 0x27,
+      0x2f, 0xee, 0xef, 0x6e, 0x6f, 0x37, 0x3d, 0x3f, 0x42, 0x45, 0x90, 0x91,
+      0xfe, 0xff, 0x53, 0x67, 0x75, 0xc8, 0xc9, 0xd0, 0xd1, 0xd8, 0xd9, 0xe7,
+      0xfe, 0xff,
+  };
+  static constexpr singleton singletons1[] = {
+      {0x00, 6},  {0x01, 1}, {0x03, 1},  {0x04, 2}, {0x08, 8},  {0x09, 2},
+      {0x0a, 5},  {0x0b, 2}, {0x0e, 4},  {0x10, 1}, {0x11, 2},  {0x12, 5},
+      {0x13, 17}, {0x14, 1}, {0x15, 2},  {0x17, 2}, {0x19, 13}, {0x1c, 5},
+      {0x1d, 8},  {0x24, 1}, {0x6a, 3},  {0x6b, 2}, {0xbc, 2},  {0xd1, 2},
+      {0xd4, 12}, {0xd5, 9}, {0xd6, 2},  {0xd7, 2}, {0xda, 1},  {0xe0, 5},
+      {0xe1, 2},  {0xe8, 2}, {0xee, 32}, {0xf0, 4}, {0xf8, 2},  {0xf9, 2},
+      {0xfa, 2},  {0xfb, 1},
+  };
+  static constexpr unsigned char singletons1_lower[] = {
+      0x0c, 0x27, 0x3b, 0x3e, 0x4e, 0x4f, 0x8f, 0x9e, 0x9e, 0x9f, 0x06, 0x07,
+      0x09, 0x36, 0x3d, 0x3e, 0x56, 0xf3, 0xd0, 0xd1, 0x04, 0x14, 0x18, 0x36,
+      0x37, 0x56, 0x57, 0x7f, 0xaa, 0xae, 0xaf, 0xbd, 0x35, 0xe0, 0x12, 0x87,
+      0x89, 0x8e, 0x9e, 0x04, 0x0d, 0x0e, 0x11, 0x12, 0x29, 0x31, 0x34, 0x3a,
+      0x45, 0x46, 0x49, 0x4a, 0x4e, 0x4f, 0x64, 0x65, 0x5c, 0xb6, 0xb7, 0x1b,
+      0x1c, 0x07, 0x08, 0x0a, 0x0b, 0x14, 0x17, 0x36, 0x39, 0x3a, 0xa8, 0xa9,
+      0xd8, 0xd9, 0x09, 0x37, 0x90, 0x91, 0xa8, 0x07, 0x0a, 0x3b, 0x3e, 0x66,
+      0x69, 0x8f, 0x92, 0x6f, 0x5f, 0xee, 0xef, 0x5a, 0x62, 0x9a, 0x9b, 0x27,
+      0x28, 0x55, 0x9d, 0xa0, 0xa1, 0xa3, 0xa4, 0xa7, 0xa8, 0xad, 0xba, 0xbc,
+      0xc4, 0x06, 0x0b, 0x0c, 0x15, 0x1d, 0x3a, 0x3f, 0x45, 0x51, 0xa6, 0xa7,
+      0xcc, 0xcd, 0xa0, 0x07, 0x19, 0x1a, 0x22, 0x25, 0x3e, 0x3f, 0xc5, 0xc6,
+      0x04, 0x20, 0x23, 0x25, 0x26, 0x28, 0x33, 0x38, 0x3a, 0x48, 0x4a, 0x4c,
+      0x50, 0x53, 0x55, 0x56, 0x58, 0x5a, 0x5c, 0x5e, 0x60, 0x63, 0x65, 0x66,
+      0x6b, 0x73, 0x78, 0x7d, 0x7f, 0x8a, 0xa4, 0xaa, 0xaf, 0xb0, 0xc0, 0xd0,
+      0xae, 0xaf, 0x79, 0xcc, 0x6e, 0x6f, 0x93,
+  };
+  static constexpr unsigned char normal0[] = {
+      0x00, 0x20, 0x5f, 0x22, 0x82, 0xdf, 0x04, 0x82, 0x44, 0x08, 0x1b, 0x04,
+      0x06, 0x11, 0x81, 0xac, 0x0e, 0x80, 0xab, 0x35, 0x28, 0x0b, 0x80, 0xe0,
+      0x03, 0x19, 0x08, 0x01, 0x04, 0x2f, 0x04, 0x34, 0x04, 0x07, 0x03, 0x01,
+      0x07, 0x06, 0x07, 0x11, 0x0a, 0x50, 0x0f, 0x12, 0x07, 0x55, 0x07, 0x03,
+      0x04, 0x1c, 0x0a, 0x09, 0x03, 0x08, 0x03, 0x07, 0x03, 0x02, 0x03, 0x03,
+      0x03, 0x0c, 0x04, 0x05, 0x03, 0x0b, 0x06, 0x01, 0x0e, 0x15, 0x05, 0x3a,
+      0x03, 0x11, 0x07, 0x06, 0x05, 0x10, 0x07, 0x57, 0x07, 0x02, 0x07, 0x15,
+      0x0d, 0x50, 0x04, 0x43, 0x03, 0x2d, 0x03, 0x01, 0x04, 0x11, 0x06, 0x0f,
+      0x0c, 0x3a, 0x04, 0x1d, 0x25, 0x5f, 0x20, 0x6d, 0x04, 0x6a, 0x25, 0x80,
+      0xc8, 0x05, 0x82, 0xb0, 0x03, 0x1a, 0x06, 0x82, 0xfd, 0x03, 0x59, 0x07,
+      0x15, 0x0b, 0x17, 0x09, 0x14, 0x0c, 0x14, 0x0c, 0x6a, 0x06, 0x0a, 0x06,
+      0x1a, 0x06, 0x59, 0x07, 0x2b, 0x05, 0x46, 0x0a, 0x2c, 0x04, 0x0c, 0x04,
+      0x01, 0x03, 0x31, 0x0b, 0x2c, 0x04, 0x1a, 0x06, 0x0b, 0x03, 0x80, 0xac,
+      0x06, 0x0a, 0x06, 0x21, 0x3f, 0x4c, 0x04, 0x2d, 0x03, 0x74, 0x08, 0x3c,
+      0x03, 0x0f, 0x03, 0x3c, 0x07, 0x38, 0x08, 0x2b, 0x05, 0x82, 0xff, 0x11,
+      0x18, 0x08, 0x2f, 0x11, 0x2d, 0x03, 0x20, 0x10, 0x21, 0x0f, 0x80, 0x8c,
+      0x04, 0x82, 0x97, 0x19, 0x0b, 0x15, 0x88, 0x94, 0x05, 0x2f, 0x05, 0x3b,
+      0x07, 0x02, 0x0e, 0x18, 0x09, 0x80, 0xb3, 0x2d, 0x74, 0x0c, 0x80, 0xd6,
+      0x1a, 0x0c, 0x05, 0x80, 0xff, 0x05, 0x80, 0xdf, 0x0c, 0xee, 0x0d, 0x03,
+      0x84, 0x8d, 0x03, 0x37, 0x09, 0x81, 0x5c, 0x14, 0x80, 0xb8, 0x08, 0x80,
+      0xcb, 0x2a, 0x38, 0x03, 0x0a, 0x06, 0x38, 0x08, 0x46, 0x08, 0x0c, 0x06,
+      0x74, 0x0b, 0x1e, 0x03, 0x5a, 0x04, 0x59, 0x09, 0x80, 0x83, 0x18, 0x1c,
+      0x0a, 0x16, 0x09, 0x4c, 0x04, 0x80, 0x8a, 0x06, 0xab, 0xa4, 0x0c, 0x17,
+      0x04, 0x31, 0xa1, 0x04, 0x81, 0xda, 0x26, 0x07, 0x0c, 0x05, 0x05, 0x80,
+      0xa5, 0x11, 0x81, 0x6d, 0x10, 0x78, 0x28, 0x2a, 0x06, 0x4c, 0x04, 0x80,
+      0x8d, 0x04, 0x80, 0xbe, 0x03, 0x1b, 0x03, 0x0f, 0x0d,
+  };
+  static constexpr unsigned char normal1[] = {
+      0x5e, 0x22, 0x7b, 0x05, 0x03, 0x04, 0x2d, 0x03, 0x66, 0x03, 0x01, 0x2f,
+      0x2e, 0x80, 0x82, 0x1d, 0x03, 0x31, 0x0f, 0x1c, 0x04, 0x24, 0x09, 0x1e,
+      0x05, 0x2b, 0x05, 0x44, 0x04, 0x0e, 0x2a, 0x80, 0xaa, 0x06, 0x24, 0x04,
+      0x24, 0x04, 0x28, 0x08, 0x34, 0x0b, 0x01, 0x80, 0x90, 0x81, 0x37, 0x09,
+      0x16, 0x0a, 0x08, 0x80, 0x98, 0x39, 0x03, 0x63, 0x08, 0x09, 0x30, 0x16,
+      0x05, 0x21, 0x03, 0x1b, 0x05, 0x01, 0x40, 0x38, 0x04, 0x4b, 0x05, 0x2f,
+      0x04, 0x0a, 0x07, 0x09, 0x07, 0x40, 0x20, 0x27, 0x04, 0x0c, 0x09, 0x36,
+      0x03, 0x3a, 0x05, 0x1a, 0x07, 0x04, 0x0c, 0x07, 0x50, 0x49, 0x37, 0x33,
+      0x0d, 0x33, 0x07, 0x2e, 0x08, 0x0a, 0x81, 0x26, 0x52, 0x4e, 0x28, 0x08,
+      0x2a, 0x56, 0x1c, 0x14, 0x17, 0x09, 0x4e, 0x04, 0x1e, 0x0f, 0x43, 0x0e,
+      0x19, 0x07, 0x0a, 0x06, 0x48, 0x08, 0x27, 0x09, 0x75, 0x0b, 0x3f, 0x41,
+      0x2a, 0x06, 0x3b, 0x05, 0x0a, 0x06, 0x51, 0x06, 0x01, 0x05, 0x10, 0x03,
+      0x05, 0x80, 0x8b, 0x62, 0x1e, 0x48, 0x08, 0x0a, 0x80, 0xa6, 0x5e, 0x22,
+      0x45, 0x0b, 0x0a, 0x06, 0x0d, 0x13, 0x39, 0x07, 0x0a, 0x36, 0x2c, 0x04,
+      0x10, 0x80, 0xc0, 0x3c, 0x64, 0x53, 0x0c, 0x48, 0x09, 0x0a, 0x46, 0x45,
+      0x1b, 0x48, 0x08, 0x53, 0x1d, 0x39, 0x81, 0x07, 0x46, 0x0a, 0x1d, 0x03,
+      0x47, 0x49, 0x37, 0x03, 0x0e, 0x08, 0x0a, 0x06, 0x39, 0x07, 0x0a, 0x81,
+      0x36, 0x19, 0x80, 0xb7, 0x01, 0x0f, 0x32, 0x0d, 0x83, 0x9b, 0x66, 0x75,
+      0x0b, 0x80, 0xc4, 0x8a, 0xbc, 0x84, 0x2f, 0x8f, 0xd1, 0x82, 0x47, 0xa1,
+      0xb9, 0x82, 0x39, 0x07, 0x2a, 0x04, 0x02, 0x60, 0x26, 0x0a, 0x46, 0x0a,
+      0x28, 0x05, 0x13, 0x82, 0xb0, 0x5b, 0x65, 0x4b, 0x04, 0x39, 0x07, 0x11,
+      0x40, 0x05, 0x0b, 0x02, 0x0e, 0x97, 0xf8, 0x08, 0x84, 0xd6, 0x2a, 0x09,
+      0xa2, 0xf7, 0x81, 0x1f, 0x31, 0x03, 0x11, 0x04, 0x08, 0x81, 0x8c, 0x89,
+      0x04, 0x6b, 0x05, 0x0d, 0x03, 0x09, 0x07, 0x10, 0x93, 0x60, 0x80, 0xf6,
+      0x0a, 0x73, 0x08, 0x6e, 0x17, 0x46, 0x80, 0x9a, 0x14, 0x0c, 0x57, 0x09,
+      0x19, 0x80, 0x87, 0x81, 0x47, 0x03, 0x85, 0x42, 0x0f, 0x15, 0x85, 0x50,
+      0x2b, 0x80, 0xd5, 0x2d, 0x03, 0x1a, 0x04, 0x02, 0x81, 0x70, 0x3a, 0x05,
+      0x01, 0x85, 0x00, 0x80, 0xd7, 0x29, 0x4c, 0x04, 0x0a, 0x04, 0x02, 0x83,
+      0x11, 0x44, 0x4c, 0x3d, 0x80, 0xc2, 0x3c, 0x06, 0x01, 0x04, 0x55, 0x05,
+      0x1b, 0x34, 0x02, 0x81, 0x0e, 0x2c, 0x04, 0x64, 0x0c, 0x56, 0x0a, 0x80,
+      0xae, 0x38, 0x1d, 0x0d, 0x2c, 0x04, 0x09, 0x07, 0x02, 0x0e, 0x06, 0x80,
+      0x9a, 0x83, 0xd8, 0x08, 0x0d, 0x03, 0x0d, 0x03, 0x74, 0x0c, 0x59, 0x07,
+      0x0c, 0x14, 0x0c, 0x04, 0x38, 0x08, 0x0a, 0x06, 0x28, 0x08, 0x22, 0x4e,
+      0x81, 0x54, 0x0c, 0x15, 0x03, 0x03, 0x05, 0x07, 0x09, 0x19, 0x07, 0x07,
+      0x09, 0x03, 0x0d, 0x07, 0x29, 0x80, 0xcb, 0x25, 0x0a, 0x84, 0x06,
+  };
+  auto lower = static_cast<uint16_t>(cp);
+  if (cp < 0x10000) {
+    return is_printable(lower, singletons0,
+                        sizeof(singletons0) / sizeof(*singletons0),
+                        singletons0_lower, normal0, sizeof(normal0));
+  }
+  if (cp < 0x20000) {
+    return is_printable(lower, singletons1,
+                        sizeof(singletons1) / sizeof(*singletons1),
+                        singletons1_lower, normal1, sizeof(normal1));
+  }
+  if (0x2a6de <= cp && cp < 0x2a700) return false;
+  if (0x2b735 <= cp && cp < 0x2b740) return false;
+  if (0x2b81e <= cp && cp < 0x2b820) return false;
+  if (0x2cea2 <= cp && cp < 0x2ceb0) return false;
+  if (0x2ebe1 <= cp && cp < 0x2f800) return false;
+  if (0x2fa1e <= cp && cp < 0x30000) return false;
+  if (0x3134b <= cp && cp < 0xe0100) return false;
+  if (0xe01f0 <= cp && cp < 0x110000) return false;
+  return cp < 0x110000;
 }
 
-FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const char) {
-  return add_space ? " '{}'" : "'{}'";
+inline auto needs_escape(uint32_t cp) -> bool {
+  return cp < 0x20 || cp == 0x7f || cp == '"' || cp == '\\' ||
+         !is_printable(cp);
 }
-FMT_CONSTEXPR const wchar_t* format_str_quoted(bool add_space, const wchar_t) {
-  return add_space ? L" '{}'" : L"'{}'";
+
+template <typename Char> struct find_escape_result {
+  const Char* begin;
+  const Char* end;
+  uint32_t cp;
+};
+
+template <typename Char>
+auto find_escape(const Char* begin, const Char* end)
+    -> find_escape_result<Char> {
+  for (; begin != end; ++begin) {
+    auto cp = static_cast<typename std::make_unsigned<Char>::type>(*begin);
+    if (sizeof(Char) == 1 && cp >= 0x80) continue;
+    if (needs_escape(cp)) return {begin, begin + 1, cp};
+  }
+  return {begin, nullptr, 0};
+}
+
+inline auto find_escape(const char* begin, const char* end)
+    -> find_escape_result<char> {
+  if (!is_utf8()) return find_escape<char>(begin, end);
+  auto result = find_escape_result<char>{end, nullptr, 0};
+  for_each_codepoint(string_view(begin, to_unsigned(end - begin)),
+                     [&](uint32_t cp, string_view sv) {
+                       if (needs_escape(cp)) {
+                         result = {sv.begin(), sv.end(), cp};
+                         return false;
+                       }
+                       return true;
+                     });
+  return result;
+}
+
+template <typename Char, typename OutputIt>
+auto write_range_entry(OutputIt out, basic_string_view<Char> str) -> OutputIt {
+  *out++ = '"';
+  auto begin = str.begin(), end = str.end();
+  do {
+    auto escape = find_escape(begin, end);
+    out = copy_str<Char>(begin, escape.begin, out);
+    begin = escape.end;
+    if (!begin) break;
+    auto c = static_cast<Char>(escape.cp);
+    switch (escape.cp) {
+    case '\n':
+      *out++ = '\\';
+      c = 'n';
+      break;
+    case '\r':
+      *out++ = '\\';
+      c = 'r';
+      break;
+    case '\t':
+      *out++ = '\\';
+      c = 't';
+      break;
+    case '"':
+      FMT_FALLTHROUGH;
+    case '\\':
+      *out++ = '\\';
+      break;
+    default:
+      if (is_utf8()) {
+        if (escape.cp < 0x100) {
+          out = format_to(out, "\\x{:02x}", escape.cp);
+          continue;
+        }
+        if (escape.cp < 0x10000) {
+          out = format_to(out, "\\u{:04x}", escape.cp);
+          continue;
+        }
+        if (escape.cp < 0x110000) {
+          out = format_to(out, "\\U{:08x}", escape.cp);
+          continue;
+        }
+      }
+      for (Char escape_char : basic_string_view<Char>(
+               escape.begin, to_unsigned(escape.end - escape.begin))) {
+        out = format_to(
+            out, "\\x{:02x}",
+            static_cast<typename std::make_unsigned<Char>::type>(escape_char));
+      }
+      continue;
+    }
+    *out++ = c;
+  } while (begin != end);
+  *out++ = '"';
+  return out;
+}
+
+template <typename Char, typename OutputIt, typename T,
+          FMT_ENABLE_IF(std::is_convertible<T, std_string_view<char>>::value)>
+inline auto write_range_entry(OutputIt out, const T& str) -> OutputIt {
+  auto sv = std_string_view<Char>(str);
+  return write_range_entry<Char>(out, basic_string_view<Char>(sv));
+}
+
+template <typename Char, typename OutputIt, typename Arg,
+          FMT_ENABLE_IF(std::is_same<Arg, Char>::value)>
+OutputIt write_range_entry(OutputIt out, const Arg v) {
+  *out++ = '\'';
+  *out++ = v;
+  *out++ = '\'';
+  return out;
+}
+
+template <
+    typename Char, typename OutputIt, typename Arg,
+    FMT_ENABLE_IF(!is_std_string_like<typename std::decay<Arg>::type>::value &&
+                  !std::is_same<Arg, Char>::value)>
+OutputIt write_range_entry(OutputIt out, const Arg& v) {
+  return write<Char>(out, v);
 }
 
 }  // namespace detail
@@ -193,148 +547,205 @@ template <typename T> struct is_tuple_like {
 template <typename TupleT, typename Char>
 struct formatter<TupleT, Char, enable_if_t<fmt::is_tuple_like<TupleT>::value>> {
  private:
-  // C++11 generic lambda for format()
+  // C++11 generic lambda for format().
   template <typename FormatContext> struct format_each {
     template <typename T> void operator()(const T& v) {
-      if (i > 0) {
-        if (formatting.add_prepostfix_space) {
-          *out++ = ' ';
-        }
-        out = detail::copy(formatting.delimiter, out);
-      }
-      out = format_to(out,
-                      detail::format_str_quoted(
-                          (formatting.add_delimiter_spaces && i > 0), v),
-                      v);
+      if (i > 0) out = detail::write_delimiter(out);
+      out = detail::write_range_entry<Char>(out, v);
       ++i;
     }
-
-    formatting_tuple<Char>& formatting;
-    size_t& i;
-    typename std::add_lvalue_reference<decltype(
-        std::declval<FormatContext>().out())>::type out;
+    int i;
+    typename FormatContext::iterator& out;
   };
 
  public:
-  formatting_tuple<Char> formatting;
-
-  template <typename ParseContext>
-  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 out = ctx.out();
-    size_t i = 0;
-    detail::copy(formatting.prefix, out);
-
-    detail::for_each(values, format_each<FormatContext>{formatting, i, out});
-    if (formatting.add_prepostfix_space) {
-      *out++ = ' ';
-    }
-    detail::copy(formatting.postfix, out);
-
-    return ctx.out();
-  }
-};
-
-template <typename T, typename Char> struct is_range {
-  static FMT_CONSTEXPR_DECL const bool value =
-      detail::is_range_<T>::value && !detail::is_like_std_string<T>::value &&
-      !std::is_convertible<T, std::basic_string<Char>>::value &&
-      !std::is_constructible<detail::std_string_view<Char>, T>::value;
-};
-
-template <typename RangeT, typename Char>
-struct formatter<RangeT, Char,
-                 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()) {
-    return formatting.parse(ctx);
-  }
-
-  template <typename FormatContext>
-  typename FormatContext::iterator format(const RangeT& values,
-                                          FormatContext& ctx) {
-    auto out = detail::copy(formatting.prefix, ctx.out());
-    size_t i = 0;
-    auto it = values.begin();
-    auto end = values.end();
-    for (; it != end; ++it) {
-      if (i > 0) {
-        if (formatting.add_prepostfix_space) *out++ = ' ';
-        out = detail::copy(formatting.delimiter, out);
-      }
-      out = format_to(out,
-                      detail::format_str_quoted(
-                          (formatting.add_delimiter_spaces && i > 0), *it),
-                      *it);
-      if (++i > formatting.range_length_limit) {
-        out = format_to(out, " ... <other elements>");
-        break;
-      }
-    }
-    if (formatting.add_prepostfix_space) *out++ = ' ';
-    return detail::copy(formatting.postfix, out);
-  }
-};
-
-template <typename Char, typename... T> struct tuple_arg_join : detail::view {
-  const std::tuple<T...>& tuple;
-  basic_string_view<Char> sep;
-
-  tuple_arg_join(const std::tuple<T...>& t, basic_string_view<Char> s)
-      : tuple{t}, sep{s} {}
-};
-
-template <typename Char, typename... T>
-struct formatter<tuple_arg_join<Char, T...>, Char> {
   template <typename ParseContext>
   FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
     return ctx.begin();
   }
 
+  template <typename FormatContext = format_context>
+  auto format(const TupleT& values, FormatContext& ctx) -> decltype(ctx.out()) {
+    auto out = ctx.out();
+    *out++ = '(';
+    detail::for_each(values, format_each<FormatContext>{0, out});
+    *out++ = ')';
+    return out;
+  }
+};
+
+template <typename T, typename Char> struct is_range {
+  static FMT_CONSTEXPR_DECL const bool value =
+      detail::is_range_<T>::value && !detail::is_std_string_like<T>::value &&
+      !detail::is_map<T>::value &&
+      !std::is_convertible<T, std::basic_string<Char>>::value &&
+      !std::is_constructible<detail::std_string_view<Char>, T>::value;
+};
+
+template <typename T, typename Char>
+struct formatter<
+    T, Char,
+    enable_if_t<
+        fmt::is_range<T, Char>::value
+// Workaround a bug in MSVC 2019 and earlier.
+#if !FMT_MSC_VER
+        && (is_formattable<detail::value_type<T>, Char>::value ||
+            detail::has_fallback_formatter<detail::value_type<T>, Char>::value)
+#endif
+        >> {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <
+      typename FormatContext, typename U,
+      FMT_ENABLE_IF(
+          std::is_same<U, conditional_t<detail::has_const_begin_end<T>::value,
+                                        const T, T>>::value)>
+  auto format(U& range, FormatContext& ctx) -> decltype(ctx.out()) {
+#ifdef FMT_DEPRECATED_BRACED_RANGES
+    Char prefix = '{';
+    Char postfix = '}';
+#else
+    Char prefix = detail::is_set<T>::value ? '{' : '[';
+    Char postfix = detail::is_set<T>::value ? '}' : ']';
+#endif
+    auto out = ctx.out();
+    *out++ = prefix;
+    int i = 0;
+    auto it = std::begin(range);
+    auto end = std::end(range);
+    for (; it != end; ++it) {
+      if (i > 0) out = detail::write_delimiter(out);
+      out = detail::write_range_entry<Char>(out, *it);
+      ++i;
+    }
+    *out++ = postfix;
+    return out;
+  }
+};
+
+template <typename T, typename Char>
+struct formatter<
+    T, Char,
+    enable_if_t<
+        detail::is_map<T>::value
+// Workaround a bug in MSVC 2019 and earlier.
+#if !FMT_MSC_VER
+        && (is_formattable<detail::value_type<T>, Char>::value ||
+            detail::has_fallback_formatter<detail::value_type<T>, Char>::value)
+#endif
+        >> {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <
+      typename FormatContext, typename U,
+      FMT_ENABLE_IF(
+          std::is_same<U, conditional_t<detail::has_const_begin_end<T>::value,
+                                        const T, T>>::value)>
+  auto format(U& map, FormatContext& ctx) -> decltype(ctx.out()) {
+    auto out = ctx.out();
+    *out++ = '{';
+    int i = 0;
+    for (const auto& item : map) {
+      if (i > 0) out = detail::write_delimiter(out);
+      out = detail::write_range_entry<Char>(out, item.first);
+      *out++ = ':';
+      *out++ = ' ';
+      out = detail::write_range_entry<Char>(out, item.second);
+      ++i;
+    }
+    *out++ = '}';
+    return out;
+  }
+};
+
+template <typename Char, typename... T> struct tuple_join_view : detail::view {
+  const std::tuple<T...>& tuple;
+  basic_string_view<Char> sep;
+
+  tuple_join_view(const std::tuple<T...>& t, basic_string_view<Char> s)
+      : tuple(t), sep{s} {}
+};
+
+template <typename Char, typename... T>
+using tuple_arg_join = tuple_join_view<Char, T...>;
+
+// Define FMT_TUPLE_JOIN_SPECIFIERS to enable experimental format specifiers
+// support in tuple_join. It is disabled by default because of issues with
+// the dynamic width and precision.
+#ifndef FMT_TUPLE_JOIN_SPECIFIERS
+#  define FMT_TUPLE_JOIN_SPECIFIERS 0
+#endif
+
+template <typename Char, typename... T>
+struct formatter<tuple_join_view<Char, T...>, Char> {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return do_parse(ctx, std::integral_constant<size_t, sizeof...(T)>());
+  }
+
   template <typename FormatContext>
-  typename FormatContext::iterator format(
-      const tuple_arg_join<Char, T...>& value, FormatContext& ctx) {
-    return format(value, ctx, detail::make_index_sequence<sizeof...(T)>{});
+  auto format(const tuple_join_view<Char, T...>& value,
+              FormatContext& ctx) const -> typename FormatContext::iterator {
+    return do_format(value, ctx,
+                     std::integral_constant<size_t, sizeof...(T)>());
   }
 
  private:
-  template <typename FormatContext, size_t... N>
-  typename FormatContext::iterator format(
-      const tuple_arg_join<Char, T...>& value, FormatContext& ctx,
-      detail::index_sequence<N...>) {
-    return format_args(value, ctx, std::get<N>(value.tuple)...);
+  std::tuple<formatter<typename std::decay<T>::type, Char>...> formatters_;
+
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto do_parse(ParseContext& ctx,
+                              std::integral_constant<size_t, 0>)
+      -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <typename ParseContext, size_t N>
+  FMT_CONSTEXPR auto do_parse(ParseContext& ctx,
+                              std::integral_constant<size_t, N>)
+      -> decltype(ctx.begin()) {
+    auto end = ctx.begin();
+#if FMT_TUPLE_JOIN_SPECIFIERS
+    end = std::get<sizeof...(T) - N>(formatters_).parse(ctx);
+    if (N > 1) {
+      auto end1 = do_parse(ctx, std::integral_constant<size_t, N - 1>());
+      if (end != end1)
+        FMT_THROW(format_error("incompatible format specs for tuple elements"));
+    }
+#endif
+    return end;
   }
 
   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.
+  auto do_format(const tuple_join_view<Char, T...>&, FormatContext& ctx,
+                 std::integral_constant<size_t, 0>) const ->
+      typename FormatContext::iterator {
     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) {
+  template <typename FormatContext, size_t N>
+  auto do_format(const tuple_join_view<Char, T...>& value, FormatContext& ctx,
+                 std::integral_constant<size_t, N>) const ->
+      typename FormatContext::iterator {
+    auto out = std::get<sizeof...(T) - N>(formatters_)
+                   .format(std::get<sizeof...(T) - N>(value.tuple), ctx);
+    if (N > 1) {
       out = std::copy(value.sep.begin(), value.sep.end(), out);
       ctx.advance_to(out);
-      return format_args(value, ctx, args...);
+      return do_format(value, ctx, std::integral_constant<size_t, N - 1>());
     }
     return out;
   }
 };
 
+FMT_MODULE_EXPORT_BEGIN
+
 /**
   \rst
   Returns an object that formats `tuple` with elements separated by `sep`.
@@ -347,14 +758,15 @@ struct formatter<tuple_arg_join<Char, T...>, Char> {
   \endrst
  */
 template <typename... T>
-FMT_CONSTEXPR tuple_arg_join<char, T...> join(const std::tuple<T...>& tuple,
-                                              string_view sep) {
+FMT_CONSTEXPR auto join(const std::tuple<T...>& tuple, string_view sep)
+    -> tuple_join_view<char, T...> {
   return {tuple, sep};
 }
 
 template <typename... T>
-FMT_CONSTEXPR tuple_arg_join<wchar_t, T...> join(const std::tuple<T...>& tuple,
-                                                 wstring_view sep) {
+FMT_CONSTEXPR auto join(const std::tuple<T...>& tuple,
+                        basic_string_view<wchar_t> sep)
+    -> tuple_join_view<wchar_t, T...> {
   return {tuple, sep};
 }
 
@@ -370,17 +782,12 @@ FMT_CONSTEXPR tuple_arg_join<wchar_t, T...> join(const std::tuple<T...>& tuple,
   \endrst
  */
 template <typename T>
-arg_join<const T*, const T*, char> join(std::initializer_list<T> list,
-                                        string_view sep) {
-  return join(std::begin(list), std::end(list), sep);
-}
-
-template <typename T>
-arg_join<const T*, const T*, wchar_t> join(std::initializer_list<T> list,
-                                           wstring_view sep) {
+auto join(std::initializer_list<T> list, string_view sep)
+    -> join_view<const T*, const T*> {
   return join(std::begin(list), std::end(list), sep);
 }
 
+FMT_MODULE_EXPORT_END
 FMT_END_NAMESPACE
 
 #endif  // FMT_RANGES_H_

include/fmt/xchar.h

@@ -0,0 +1,236 @@
+// Formatting library for C++ - optional wchar_t and exotic character support
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_XCHAR_H_
+#define FMT_XCHAR_H_
+
+#include <cwchar>
+#include <tuple>
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+template <typename T>
+using is_exotic_char = bool_constant<!std::is_same<T, char>::value>;
+}
+
+FMT_MODULE_EXPORT_BEGIN
+
+using wstring_view = basic_string_view<wchar_t>;
+using wformat_parse_context = basic_format_parse_context<wchar_t>;
+using wformat_context = buffer_context<wchar_t>;
+using wformat_args = basic_format_args<wformat_context>;
+using wmemory_buffer = basic_memory_buffer<wchar_t>;
+
+#if FMT_GCC_VERSION && FMT_GCC_VERSION < 409
+// Workaround broken conversion on older gcc.
+template <typename... Args> using wformat_string = wstring_view;
+#else
+template <typename... Args>
+using wformat_string = basic_format_string<wchar_t, type_identity_t<Args>...>;
+#endif
+
+template <> struct is_char<wchar_t> : std::true_type {};
+template <> struct is_char<detail::char8_type> : std::true_type {};
+template <> struct is_char<char16_t> : std::true_type {};
+template <> struct is_char<char32_t> : std::true_type {};
+
+template <typename... Args>
+constexpr format_arg_store<wformat_context, Args...> make_wformat_args(
+    const Args&... args) {
+  return {args...};
+}
+
+inline namespace literals {
+constexpr auto operator"" _format(const wchar_t* s, size_t n)
+    -> detail::udl_formatter<wchar_t> {
+  return {{s, n}};
+}
+
+#if FMT_USE_USER_DEFINED_LITERALS && !FMT_USE_NONTYPE_TEMPLATE_PARAMETERS
+constexpr detail::udl_arg<wchar_t> operator"" _a(const wchar_t* s, size_t) {
+  return {s};
+}
+#endif
+}  // namespace literals
+
+template <typename It, typename Sentinel>
+auto join(It begin, Sentinel end, wstring_view sep)
+    -> join_view<It, Sentinel, wchar_t> {
+  return {begin, end, sep};
+}
+
+template <typename Range>
+auto join(Range&& range, wstring_view sep)
+    -> join_view<detail::iterator_t<Range>, detail::sentinel_t<Range>,
+                 wchar_t> {
+  return join(std::begin(range), std::end(range), sep);
+}
+
+template <typename T>
+auto join(std::initializer_list<T> list, wstring_view sep)
+    -> join_view<const T*, const T*, wchar_t> {
+  return join(std::begin(list), std::end(list), sep);
+}
+
+template <typename Char, FMT_ENABLE_IF(!std::is_same<Char, char>::value)>
+auto vformat(basic_string_view<Char> format_str,
+             basic_format_args<buffer_context<type_identity_t<Char>>> args)
+    -> std::basic_string<Char> {
+  basic_memory_buffer<Char> buffer;
+  detail::vformat_to(buffer, format_str, args);
+  return to_string(buffer);
+}
+
+// Pass char_t as a default template parameter instead of using
+// std::basic_string<char_t<S>> to reduce the symbol size.
+template <typename S, typename... Args, typename Char = char_t<S>,
+          FMT_ENABLE_IF(!std::is_same<Char, char>::value)>
+auto format(const S& format_str, Args&&... args) -> std::basic_string<Char> {
+  const auto& vargs = fmt::make_args_checked<Args...>(format_str, args...);
+  return vformat(to_string_view(format_str), vargs);
+}
+
+template <typename Locale, typename S, typename Char = char_t<S>,
+          FMT_ENABLE_IF(detail::is_locale<Locale>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto vformat(
+    const Locale& loc, const S& format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args)
+    -> std::basic_string<Char> {
+  return detail::vformat(loc, to_string_view(format_str), args);
+}
+
+template <typename Locale, typename S, typename... Args,
+          typename Char = char_t<S>,
+          FMT_ENABLE_IF(detail::is_locale<Locale>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto format(const Locale& loc, const S& format_str, Args&&... args)
+    -> std::basic_string<Char> {
+  return detail::vformat(loc, to_string_view(format_str),
+                         fmt::make_args_checked<Args...>(format_str, args...));
+}
+
+template <typename OutputIt, typename S, typename Char = char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_exotic_char<Char>::value)>
+auto vformat_to(OutputIt out, const S& format_str,
+                basic_format_args<buffer_context<type_identity_t<Char>>> args)
+    -> OutputIt {
+  auto&& buf = detail::get_buffer<Char>(out);
+  detail::vformat_to(buf, to_string_view(format_str), args);
+  return detail::get_iterator(buf);
+}
+
+template <typename OutputIt, typename S, typename... Args,
+          typename Char = char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto format_to(OutputIt out, const S& fmt, Args&&... args) -> OutputIt {
+  const auto& vargs = fmt::make_args_checked<Args...>(fmt, args...);
+  return vformat_to(out, to_string_view(fmt), vargs);
+}
+
+template <typename S, typename... Args, typename Char, size_t SIZE,
+          typename Allocator, FMT_ENABLE_IF(detail::is_string<S>::value)>
+FMT_DEPRECATED auto format_to(basic_memory_buffer<Char, SIZE, Allocator>& buf,
+                              const S& format_str, Args&&... args) ->
+    typename buffer_context<Char>::iterator {
+  const auto& vargs = fmt::make_args_checked<Args...>(format_str, args...);
+  detail::vformat_to(buf, to_string_view(format_str), vargs, {});
+  return detail::buffer_appender<Char>(buf);
+}
+
+template <typename Locale, typename S, typename OutputIt, typename... Args,
+          typename Char = char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_locale<Locale>::value&&
+                                detail::is_exotic_char<Char>::value)>
+inline auto vformat_to(
+    OutputIt out, const Locale& loc, const S& format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) -> OutputIt {
+  auto&& buf = detail::get_buffer<Char>(out);
+  vformat_to(buf, to_string_view(format_str), args, detail::locale_ref(loc));
+  return detail::get_iterator(buf);
+}
+
+template <
+    typename OutputIt, typename Locale, typename S, typename... Args,
+    typename Char = char_t<S>,
+    bool enable = detail::is_output_iterator<OutputIt, Char>::value&&
+        detail::is_locale<Locale>::value&& detail::is_exotic_char<Char>::value>
+inline auto format_to(OutputIt out, const Locale& loc, const S& format_str,
+                      Args&&... args) ->
+    typename std::enable_if<enable, OutputIt>::type {
+  const auto& vargs = fmt::make_args_checked<Args...>(format_str, args...);
+  return vformat_to(out, loc, to_string_view(format_str), vargs);
+}
+
+template <typename OutputIt, typename Char, typename... Args,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto vformat_to_n(
+    OutputIt out, size_t n, basic_string_view<Char> format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args)
+    -> format_to_n_result<OutputIt> {
+  detail::iterator_buffer<OutputIt, Char, detail::fixed_buffer_traits> buf(out,
+                                                                           n);
+  detail::vformat_to(buf, format_str, args);
+  return {buf.out(), buf.count()};
+}
+
+template <typename OutputIt, typename S, typename... Args,
+          typename Char = char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto format_to_n(OutputIt out, size_t n, const S& fmt,
+                        const Args&... args) -> format_to_n_result<OutputIt> {
+  const auto& vargs = fmt::make_args_checked<Args...>(fmt, args...);
+  return vformat_to_n(out, n, to_string_view(fmt), vargs);
+}
+
+template <typename S, typename... Args, typename Char = char_t<S>,
+          FMT_ENABLE_IF(detail::is_exotic_char<Char>::value)>
+inline auto formatted_size(const S& fmt, Args&&... args) -> size_t {
+  detail::counting_buffer<Char> buf;
+  const auto& vargs = fmt::make_args_checked<Args...>(fmt, args...);
+  detail::vformat_to(buf, to_string_view(fmt), vargs);
+  return buf.count();
+}
+
+inline void vprint(std::FILE* f, wstring_view fmt, wformat_args args) {
+  wmemory_buffer buffer;
+  detail::vformat_to(buffer, fmt, args);
+  buffer.push_back(L'\0');
+  if (std::fputws(buffer.data(), f) == -1)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot write to file")));
+}
+
+inline void vprint(wstring_view fmt, wformat_args args) {
+  vprint(stdout, fmt, args);
+}
+
+template <typename... T>
+void print(std::FILE* f, wformat_string<T...> fmt, T&&... args) {
+  return vprint(f, wstring_view(fmt), fmt::make_wformat_args(args...));
+}
+
+template <typename... T> void print(wformat_string<T...> fmt, T&&... args) {
+  return vprint(wstring_view(fmt), fmt::make_wformat_args(args...));
+}
+
+/**
+  Converts *value* to ``std::wstring`` using the default format for type *T*.
+ */
+template <typename T> inline auto to_wstring(const T& value) -> std::wstring {
+  return format(FMT_STRING(L"{}"), value);
+}
+FMT_MODULE_EXPORT_END
+FMT_END_NAMESPACE
+
+#endif  // FMT_XCHAR_H_

src/fmt.cc

@@ -0,0 +1,99 @@
+module;
+#ifndef __cpp_modules
+#  error Module not supported.
+#endif
+
+// put all implementation-provided headers into the global module fragment
+// to prevent attachment to this module
+#if !defined(_CRT_SECURE_NO_WARNINGS) && defined(_MSC_VER)
+#  define _CRT_SECURE_NO_WARNINGS
+#endif
+#if !defined(WIN32_LEAN_AND_MEAN) && defined(_WIN32)
+#  define WIN32_LEAN_AND_MEAN
+#endif
+
+#include <algorithm>
+#include <cctype>
+#include <cerrno>
+#include <chrono>
+#include <climits>
+#include <clocale>
+#include <cmath>
+#include <cstdarg>
+#include <cstddef>
+#include <cstdint>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <ctime>
+#include <cwchar>
+#include <exception>
+#include <functional>
+#include <iterator>
+#include <limits>
+#include <locale>
+#include <memory>
+#include <ostream>
+#include <sstream>
+#include <stdexcept>
+#include <string>
+#include <string_view>
+#include <system_error>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+#if _MSC_VER
+#  include <intrin.h>
+#endif
+#if defined __APPLE__ || defined(__FreeBSD__)
+#  include <xlocale.h>
+#endif
+#if __has_include(<winapifamily.h>)
+#  include <winapifamily.h>
+#endif
+#if (__has_include(<fcntl.h>) || defined(__APPLE__) || \
+     defined(__linux__)) &&                            \
+    (!defined(WINAPI_FAMILY) || (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP))
+#  include <fcntl.h>
+#  include <sys/stat.h>
+#  include <sys/types.h>
+#  ifndef _WIN32
+#    include <unistd.h>
+#  else
+#    include <io.h>
+#  endif
+#endif
+#ifdef _WIN32
+#  include <windows.h>
+#endif
+
+export module fmt;
+
+#define FMT_MODULE_EXPORT export
+#define FMT_MODULE_EXPORT_BEGIN export {
+#define FMT_MODULE_EXPORT_END }
+#define FMT_BEGIN_DETAIL_NAMESPACE \
+  }                                \
+  namespace detail {
+#define FMT_END_DETAIL_NAMESPACE \
+  }                              \
+  export {
+// all library-provided declarations and definitions
+// must be in the module purview to be exported
+#include "fmt/args.h"
+#include "fmt/chrono.h"
+#include "fmt/color.h"
+#include "fmt/compile.h"
+#include "fmt/format.h"
+#include "fmt/os.h"
+#include "fmt/printf.h"
+#include "fmt/xchar.h"
+
+// gcc doesn't yet implement private module fragments
+#if !FMT_GCC_VERSION
+module : private;
+#endif
+
+#include "format.cc"
+#include "os.cc"

src/format.cc

@@ -10,6 +10,52 @@
 FMT_BEGIN_NAMESPACE
 namespace detail {
 
+// DEPRECATED!
+template <typename T = void> struct basic_data {
+  FMT_API static constexpr const char digits[100][2] = {
+      {'0', '0'}, {'0', '1'}, {'0', '2'}, {'0', '3'}, {'0', '4'}, {'0', '5'},
+      {'0', '6'}, {'0', '7'}, {'0', '8'}, {'0', '9'}, {'1', '0'}, {'1', '1'},
+      {'1', '2'}, {'1', '3'}, {'1', '4'}, {'1', '5'}, {'1', '6'}, {'1', '7'},
+      {'1', '8'}, {'1', '9'}, {'2', '0'}, {'2', '1'}, {'2', '2'}, {'2', '3'},
+      {'2', '4'}, {'2', '5'}, {'2', '6'}, {'2', '7'}, {'2', '8'}, {'2', '9'},
+      {'3', '0'}, {'3', '1'}, {'3', '2'}, {'3', '3'}, {'3', '4'}, {'3', '5'},
+      {'3', '6'}, {'3', '7'}, {'3', '8'}, {'3', '9'}, {'4', '0'}, {'4', '1'},
+      {'4', '2'}, {'4', '3'}, {'4', '4'}, {'4', '5'}, {'4', '6'}, {'4', '7'},
+      {'4', '8'}, {'4', '9'}, {'5', '0'}, {'5', '1'}, {'5', '2'}, {'5', '3'},
+      {'5', '4'}, {'5', '5'}, {'5', '6'}, {'5', '7'}, {'5', '8'}, {'5', '9'},
+      {'6', '0'}, {'6', '1'}, {'6', '2'}, {'6', '3'}, {'6', '4'}, {'6', '5'},
+      {'6', '6'}, {'6', '7'}, {'6', '8'}, {'6', '9'}, {'7', '0'}, {'7', '1'},
+      {'7', '2'}, {'7', '3'}, {'7', '4'}, {'7', '5'}, {'7', '6'}, {'7', '7'},
+      {'7', '8'}, {'7', '9'}, {'8', '0'}, {'8', '1'}, {'8', '2'}, {'8', '3'},
+      {'8', '4'}, {'8', '5'}, {'8', '6'}, {'8', '7'}, {'8', '8'}, {'8', '9'},
+      {'9', '0'}, {'9', '1'}, {'9', '2'}, {'9', '3'}, {'9', '4'}, {'9', '5'},
+      {'9', '6'}, {'9', '7'}, {'9', '8'}, {'9', '9'}};
+  FMT_API static constexpr const char hex_digits[] = "0123456789abcdef";
+  FMT_API static constexpr const char signs[4] = {0, '-', '+', ' '};
+  FMT_API static constexpr const char left_padding_shifts[5] = {31, 31, 0, 1,
+                                                                0};
+  FMT_API static constexpr const char right_padding_shifts[5] = {0, 31, 0, 1,
+                                                                 0};
+  FMT_API static constexpr const unsigned prefixes[4] = {0, 0, 0x1000000u | '+',
+                                                         0x1000000u | ' '};
+};
+
+#ifdef FMT_SHARED
+// Required for -flto, -fivisibility=hidden and -shared to work
+extern template struct basic_data<void>;
+#endif
+
+#if __cplusplus < 201703L
+// DEPRECATED! These are here only for ABI compatiblity.
+template <typename T> constexpr const char basic_data<T>::digits[][2];
+template <typename T> constexpr const char basic_data<T>::hex_digits[];
+template <typename T> constexpr const char basic_data<T>::signs[];
+template <typename T> constexpr const char basic_data<T>::left_padding_shifts[];
+template <typename T>
+constexpr const char basic_data<T>::right_padding_shifts[];
+template <typename T> constexpr const unsigned basic_data<T>::prefixes[];
+#endif
+
 template <typename T>
 int format_float(char* buf, std::size_t size, const char* format, int precision,
                  T value) {
@@ -23,9 +69,12 @@ int format_float(char* buf, std::size_t size, const char* format, int precision,
   return precision < 0 ? snprintf_ptr(buf, size, format, value)
                        : snprintf_ptr(buf, size, format, precision, value);
 }
-}  // namespace detail
 
-template struct FMT_INSTANTIATION_DEF_API detail::basic_data<void>;
+template FMT_API dragonbox::decimal_fp<float> dragonbox::to_decimal(float x)
+    FMT_NOEXCEPT;
+template FMT_API dragonbox::decimal_fp<double> dragonbox::to_decimal(double x)
+    FMT_NOEXCEPT;
+}  // namespace detail
 
 // Workaround a bug in MSVC2013 that prevents instantiation of format_float.
 int (*instantiate_format_float)(double, int, detail::float_specs,
@@ -38,15 +87,18 @@ template FMT_API std::locale detail::locale_ref::get<std::locale>() const;
 
 // Explicit instantiations for char.
 
-template FMT_API std::string detail::grouping_impl<char>(locale_ref);
-template FMT_API char detail::thousands_sep_impl(locale_ref);
+template FMT_API auto detail::thousands_sep_impl(locale_ref)
+    -> thousands_sep_result<char>;
 template FMT_API char detail::decimal_point_impl(locale_ref);
 
 template FMT_API void detail::buffer<char>::append(const char*, const char*);
 
-template FMT_API FMT_BUFFER_CONTEXT(char)::iterator detail::vformat_to(
+// DEPRECATED!
+// There is no correspondent extern template in format.h because of
+// incompatibility between clang and gcc (#2377).
+template FMT_API void detail::vformat_to(
     detail::buffer<char>&, string_view,
-    basic_format_args<FMT_BUFFER_CONTEXT(char)>);
+    basic_format_args<FMT_BUFFER_CONTEXT(char)>, detail::locale_ref);
 
 template FMT_API int detail::snprintf_float(double, int, detail::float_specs,
                                             detail::buffer<char>&);
@@ -60,10 +112,13 @@ template FMT_API int detail::format_float(long double, int, detail::float_specs,
 
 // Explicit instantiations for wchar_t.
 
-template FMT_API std::string detail::grouping_impl<wchar_t>(locale_ref);
-template FMT_API wchar_t detail::thousands_sep_impl(locale_ref);
+template FMT_API auto detail::thousands_sep_impl(locale_ref)
+    -> thousands_sep_result<wchar_t>;
 template FMT_API wchar_t detail::decimal_point_impl(locale_ref);
 
 template FMT_API void detail::buffer<wchar_t>::append(const wchar_t*,
                                                       const wchar_t*);
+
+template struct detail::basic_data<void>;
+
 FMT_END_NAMESPACE

src/os.cc

@@ -25,21 +25,18 @@
 #      define WIN32_LEAN_AND_MEAN
 #    endif
 #    include <io.h>
-#    include <windows.h>
-
-#    define O_CREAT _O_CREAT
-#    define O_TRUNC _O_TRUNC
 
 #    ifndef S_IRUSR
 #      define S_IRUSR _S_IREAD
 #    endif
-
 #    ifndef S_IWUSR
 #      define S_IWUSR _S_IWRITE
 #    endif
-
-#    ifdef __MINGW32__
-#      define _SH_DENYNO 0x40
+#    ifndef S_IRGRP
+#      define S_IRGRP 0
+#    endif
+#    ifndef S_IROTH
+#      define S_IROTH 0
 #    endif
 #  endif  // _WIN32
 #endif    // FMT_USE_FCNTL
@@ -55,16 +52,16 @@
 namespace {
 #ifdef _WIN32
 // Return type of read and write functions.
-using RWResult = int;
+using rwresult = int;
 
 // On Windows the count argument to read and write is unsigned, so convert
 // it from size_t preventing integer overflow.
 inline unsigned convert_rwcount(std::size_t count) {
   return count <= UINT_MAX ? static_cast<unsigned>(count) : UINT_MAX;
 }
-#else
+#elif FMT_USE_FCNTL
 // Return type of read and write functions.
-using RWResult = ssize_t;
+using rwresult = ssize_t;
 
 inline std::size_t convert_rwcount(std::size_t count) { return count; }
 #endif
@@ -73,14 +70,14 @@ inline std::size_t convert_rwcount(std::size_t count) { return count; }
 FMT_BEGIN_NAMESPACE
 
 #ifdef _WIN32
-detail::utf16_to_utf8::utf16_to_utf8(wstring_view s) {
+detail::utf16_to_utf8::utf16_to_utf8(basic_string_view<wchar_t> s) {
   if (int error_code = convert(s)) {
     FMT_THROW(windows_error(error_code,
                             "cannot convert string from UTF-16 to UTF-8"));
   }
 }
 
-int detail::utf16_to_utf8::convert(wstring_view s) {
+int detail::utf16_to_utf8::convert(basic_string_view<wchar_t> s) {
   if (s.size() > INT_MAX) return ERROR_INVALID_PARAMETER;
   int s_size = static_cast<int>(s.size());
   if (s_size == 0) {
@@ -101,45 +98,85 @@ int detail::utf16_to_utf8::convert(wstring_view s) {
   return 0;
 }
 
-void windows_error::init(int err_code, string_view format_str,
-                         format_args args) {
-  error_code_ = err_code;
-  memory_buffer buffer;
-  detail::format_windows_error(buffer, err_code, vformat(format_str, args));
-  std::runtime_error& base = *this;
-  base = std::runtime_error(to_string(buffer));
+namespace detail {
+
+class system_message {
+  system_message(const system_message&) = delete;
+  void operator=(const system_message&) = delete;
+
+  unsigned long result_;
+  wchar_t* message_;
+
+  static bool is_whitespace(wchar_t c) FMT_NOEXCEPT {
+    return c == L' ' || c == L'\n' || c == L'\r' || c == L'\t' || c == L'\0';
+  }
+
+ public:
+  explicit system_message(unsigned long error_code)
+      : result_(0), message_(nullptr) {
+    result_ = FormatMessageW(
+        FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM |
+            FORMAT_MESSAGE_IGNORE_INSERTS,
+        nullptr, error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+        reinterpret_cast<wchar_t*>(&message_), 0, nullptr);
+    if (result_ != 0) {
+      while (result_ != 0 && is_whitespace(message_[result_ - 1])) {
+        --result_;
+      }
+    }
+  }
+  ~system_message() { LocalFree(message_); }
+  explicit operator bool() const FMT_NOEXCEPT { return result_ != 0; }
+  operator basic_string_view<wchar_t>() const FMT_NOEXCEPT {
+    return basic_string_view<wchar_t>(message_, result_);
+  }
+};
+
+class utf8_system_category final : public std::error_category {
+ public:
+  const char* name() const FMT_NOEXCEPT override { return "system"; }
+  std::string message(int error_code) const override {
+    system_message msg(error_code);
+    if (msg) {
+      utf16_to_utf8 utf8_message;
+      if (utf8_message.convert(msg) == ERROR_SUCCESS) {
+        return utf8_message.str();
+      }
+    }
+    return "unknown error";
+  }
+};
+
+}  // namespace detail
+
+FMT_API const std::error_category& system_category() FMT_NOEXCEPT {
+  static const detail::utf8_system_category category;
+  return category;
+}
+
+std::system_error vwindows_error(int err_code, string_view format_str,
+                                 format_args args) {
+  auto ec = std::error_code(err_code, system_category());
+  return std::system_error(ec, vformat(format_str, args));
 }
 
 void detail::format_windows_error(detail::buffer<char>& out, int error_code,
-                                  string_view message) FMT_NOEXCEPT {
+                                  const char* message) FMT_NOEXCEPT {
   FMT_TRY {
-    wmemory_buffer buf;
-    buf.resize(inline_buffer_size);
-    for (;;) {
-      wchar_t* system_message = &buf[0];
-      int result = FormatMessageW(
-          FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, nullptr,
-          error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), system_message,
-          static_cast<uint32_t>(buf.size()), nullptr);
-      if (result != 0) {
-        utf16_to_utf8 utf8_message;
-        if (utf8_message.convert(system_message) == ERROR_SUCCESS) {
-          format_to(std::back_inserter(out), "{}: {}", message, utf8_message);
-          return;
-        }
-        break;
+    system_message msg(error_code);
+    if (msg) {
+      utf16_to_utf8 utf8_message;
+      if (utf8_message.convert(msg) == ERROR_SUCCESS) {
+        format_to(buffer_appender<char>(out), "{}: {}", message, utf8_message);
+        return;
       }
-      if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
-        break;  // Can't get error message, report error code instead.
-      buf.resize(buf.size() * 2);
     }
   }
   FMT_CATCH(...) {}
   format_error_code(out, error_code, message);
 }
 
-void report_windows_error(int error_code,
-                          fmt::string_view message) FMT_NOEXCEPT {
+void report_windows_error(int error_code, const char* message) FMT_NOEXCEPT {
   report_error(detail::format_windows_error, error_code, message);
 }
 #endif  // _WIN32
@@ -174,7 +211,10 @@ int buffered_file::fileno() const {
 
 #if FMT_USE_FCNTL
 file::file(cstring_view path, int oflag) {
-  int mode = S_IRUSR | S_IWUSR;
+#  ifdef _WIN32
+  using mode_t = int;
+#  endif
+  mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
 #  if defined(_WIN32) && !defined(__MINGW32__)
   fd_ = -1;
   FMT_POSIX_CALL(sopen_s(&fd_, path.c_str(), oflag, _SH_DENYNO, mode));
@@ -228,14 +268,14 @@ long long file::size() const {
 }
 
 std::size_t file::read(void* buffer, std::size_t count) {
-  RWResult result = 0;
+  rwresult result = 0;
   FMT_RETRY(result, FMT_POSIX_CALL(read(fd_, buffer, convert_rwcount(count))));
   if (result < 0) FMT_THROW(system_error(errno, "cannot read from file"));
   return detail::to_unsigned(result);
 }
 
 std::size_t file::write(const void* buffer, std::size_t count) {
-  RWResult result = 0;
+  rwresult result = 0;
   FMT_RETRY(result, FMT_POSIX_CALL(write(fd_, buffer, convert_rwcount(count))));
   if (result < 0) FMT_THROW(system_error(errno, "cannot write to file"));
   return detail::to_unsigned(result);
@@ -259,10 +299,10 @@ void file::dup2(int fd) {
   }
 }
 
-void file::dup2(int fd, error_code& ec) FMT_NOEXCEPT {
+void file::dup2(int fd, std::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 = std::error_code(errno, std::generic_category());
 }
 
 void file::pipe(file& read_end, file& write_end) {
@@ -288,12 +328,12 @@ void file::pipe(file& read_end, file& write_end) {
 }
 
 buffered_file file::fdopen(const char* mode) {
-  // Don't retry as fdopen doesn't return EINTR.
-  #if defined(__MINGW32__) && defined(_POSIX_)
+// Don't retry as fdopen doesn't return EINTR.
+#  if defined(__MINGW32__) && defined(_POSIX_)
   FILE* f = ::fdopen(fd_, mode);
-  #else
+#  else
   FILE* f = FMT_POSIX_CALL(fdopen(fd_, mode));
-  #endif
+#  endif
   if (!f)
     FMT_THROW(
         system_error(errno, "cannot associate stream with file descriptor"));
@@ -313,5 +353,9 @@ long getpagesize() {
   return size;
 #  endif
 }
+
+FMT_API void ostream::grow(size_t) {
+  if (this->size() == this->capacity()) flush();
+}
 #endif  // FMT_USE_FCNTL
 FMT_END_NAMESPACE

support/README

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

support/appveyor.yml

@@ -6,11 +6,8 @@ clone_depth: 1
 
 image:
   - Visual Studio 2015
-  - Visual Studio 2019
-  - Visual Studio 2017
 
 platform:
-  - Win32
   - x64
 
 environment:
@@ -18,13 +15,6 @@ environment:
   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/bazel/.bazelrc

@@ -0,0 +1 @@
+build --symlink_prefix=/ # Out of source build

support/bazel/.bazelversion

@@ -0,0 +1 @@
+4.2.1

support/bazel/BUILD.bazel

@@ -0,0 +1,29 @@
+cc_library(
+    name = "fmt",
+    srcs = [
+        #"src/fmt.cc", # No C++ module support
+        "src/format.cc",
+        "src/os.cc",
+    ],
+    hdrs = [
+        "include/fmt/args.h",
+        "include/fmt/chrono.h",
+        "include/fmt/color.h",
+        "include/fmt/compile.h",
+        "include/fmt/core.h",
+        "include/fmt/format.h",
+        "include/fmt/format-inl.h",
+        "include/fmt/locale.h",
+        "include/fmt/os.h",
+        "include/fmt/ostream.h",
+        "include/fmt/printf.h",
+        "include/fmt/ranges.h",
+        "include/fmt/xchar.h",
+    ],
+    includes = [
+        "include",
+        "src",
+    ],
+    strip_include_prefix = "include",
+    visibility = ["//visibility:public"],
+)

support/bazel/README.md

@@ -0,0 +1,73 @@
+# Bazel support
+
+To get [Bazel](https://bazel.build/) working with {fmt} you can copy the files `BUILD.bazel`, `WORKSPACE.bazel`, `.bazelrc`, and `.bazelversion` from this folder (`support/bazel`) to the root folder of this project. This way {fmt} gets bazelized and can be used with Bazel (e.g. doing a `bazel build //...` on {fmt}). 
+
+## Using {fmt} as a dependency
+
+The following minimal example shows how to use {fmt} as a dependency within a Bazel project.
+
+The following file structure is assumed:
+
+```
+example
+├── BUILD.bazel
+├── main.cpp
+└── WORKSPACE.bazel
+```
+
+*main.cpp*:
+
+```c++
+#include "fmt/core.h"
+
+int main() {
+  fmt::print("The answer is {}\n", 42);
+}
+```
+
+The expected output of this example is `The answer is 42`.
+
+*WORKSPACE.bazel*:
+
+```python
+load("@bazel_tools//tools/build_defs/repo:git.bzl", "git_repository")
+
+git_repository(
+    name = "fmt",
+    branch = "master",
+    remote = "https://github.com/fmtlib/fmt",
+    patch_cmds = [
+        "mv support/bazel/.bazelrc .bazelrc",
+        "mv support/bazel/.bazelversion .bazelversion",
+        "mv support/bazel/BUILD.bazel BUILD.bazel",
+        "mv support/bazel/WORKSPACE.bazel WORKSPACE.bazel",
+    ],
+    # Windows-related patch commands are only needed in the case MSYS2 is not installed.
+    # More details about the installation process of MSYS2 on Windows systems can be found here:
+    # https://docs.bazel.build/versions/main/install-windows.html#installing-compilers-and-language-runtimes
+    # Even if MSYS2 is installed the Windows related patch commands can still be used.
+    patch_cmds_win = [
+        "Move-Item -Path support/bazel/.bazelrc -Destination .bazelrc",
+        "Move-Item -Path support/bazel/.bazelversion -Destination .bazelversion",
+        "Move-Item -Path support/bazel/BUILD.bazel -Destination BUILD.bazel",
+        "Move-Item -Path support/bazel/WORKSPACE.bazel -Destination WORKSPACE.bazel",
+    ],
+)
+```
+
+In the *WORKSPACE* file, the {fmt} GitHub repository is fetched. Using the attribute `patch_cmds` the  files `BUILD.bazel`, `WORKSPACE.bazel`, `.bazelrc`, and `.bazelversion` are moved to the root of the {fmt} repository. This way the {fmt} repository is recognized as a bazelized workspace. 
+
+*BUILD.bazel*:
+
+```python
+cc_binary(
+    name = "Demo",
+    srcs = ["main.cpp"],
+    deps = ["@fmt"],
+)
+```
+
+The *BUILD* file defines a binary named `Demo` that has a dependency to {fmt}.
+
+To execute the binary you can run `bazel run //:Demo`.
+

support/bazel/WORKSPACE.bazel

@@ -0,0 +1 @@
+workspace(name = "fmt")

support/build-docs.py

@@ -0,0 +1,58 @@
+#!/usr/bin/env python
+# Build the documentation in CI.
+
+from __future__ import print_function
+import errno, os, shutil, subprocess, sys, urllib
+from subprocess import call, check_call, Popen, PIPE, STDOUT
+
+def rmtree_if_exists(dir):
+    try:
+        shutil.rmtree(dir)
+    except OSError as e:
+        if e.errno == errno.ENOENT:
+            pass
+
+# Build the docs.
+fmt_dir = os.path.dirname(os.path.dirname(os.path.realpath(__file__)))
+sys.path.insert(0, os.path.join(fmt_dir, 'doc'))
+import build
+build.create_build_env()
+html_dir = build.build_docs()
+
+repo = 'fmtlib.github.io'
+branch = os.environ['GITHUB_REF']
+is_ci = 'CI' in os.environ
+if is_ci and branch != 'refs/heads/master':
+    print('Branch: ' + branch)
+    exit(0) # Ignore non-master branches
+if is_ci and 'KEY' not in os.environ:
+    # Don't update the repo if building in CI from an account that doesn't have
+    # push access.
+    print('Skipping update of ' + repo)
+    exit(0)
+
+# Clone the fmtlib.github.io repo.
+rmtree_if_exists(repo)
+git_url = 'https://github.com/' if is_ci else 'git@github.com:'
+check_call(['git', 'clone', git_url + 'fmtlib/{}.git'.format(repo)])
+
+# Copy docs to the repo.
+target_dir = os.path.join(repo, 'dev')
+rmtree_if_exists(target_dir)
+shutil.copytree(html_dir, target_dir, ignore=shutil.ignore_patterns('.*'))
+if is_ci:
+    check_call(['git', 'config', '--global', 'user.name', 'fmtbot'])
+    check_call(['git', 'config', '--global', 'user.email', 'viz@fmt.dev'])
+
+# Push docs to GitHub pages.
+check_call(['git', 'add', '--all'], cwd=repo)
+if call(['git', 'diff-index', '--quiet', 'HEAD'], cwd=repo):
+    check_call(['git', 'commit', '-m', 'Update documentation'], cwd=repo)
+    cmd = 'git push'
+    if is_ci:
+        cmd += ' https://$KEY@github.com/fmtlib/fmtlib.github.io.git master'
+    p = Popen(cmd, shell=True, stdout=PIPE, stderr=STDOUT, cwd=repo)
+    # Print the output without the key.
+    print(p.communicate()[0].decode('utf-8').replace(os.environ['KEY'], '$KEY'))
+    if p.returncode != 0:
+        raise subprocess.CalledProcessError(p.returncode, cmd)

support/build.gradle

@@ -1,3 +1,4 @@
+import java.nio.file.Paths
 
 // General gradle arguments for root project
 buildscript {    
@@ -7,24 +8,25 @@ buildscript {
     }
     dependencies {
         //
-        // https://developer.android.com/studio/releases/gradle-plugin
+        // https://developer.android.com/studio/releases/gradle-plugin#updating-gradle
         //
-        // 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
+        // Notice that 4.0.0 here is the version of [Android Gradle Plugin]
+        // Accroding to URL above you will need Gradle 6.1 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'
+        classpath "com.android.tools.build:gradle:4.1.1"
     }
 }
 repositories {
     google()
     jcenter()
 }
-    
-// Output: Shared library (.so) for Android 
-apply plugin: 'com.android.library'
 
+// Project's root where CMakeLists.txt exists: rootDir/support/.cxx -> rootDir
+def rootDir = Paths.get(project.buildDir.getParent()).getParent()
+println("rootDir: ${rootDir}")
+
+// Output: Shared library (.so) for Android 
+apply plugin: "com.android.library"
 android {
     compileSdkVersion 25    // Android 7.0
 
@@ -41,13 +43,13 @@ android {
             include  "arm64-v8a", "armeabi-v7a", "x86_64"
         }
     }
+    ndkVersion "21.3.6528147" // ANDROID_NDK_HOME is deprecated. Be explicit
 
     defaultConfig {
         minSdkVersion 21    // Android 5.0+
         targetSdkVersion 25 // Follow Compile SDK
-        versionCode 21      // Follow release count
-        versionName "5.3.0" // Follow Official version
-        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+        versionCode 34      // Follow release count
+        versionName "7.1.2" // Follow Official version
         
         externalNativeBuild {
             cmake {
@@ -56,9 +58,9 @@ android {
                 arguments "-DFMT_TEST=false"            // Skip test
                 arguments "-DFMT_DOC=false"             // Skip document
                 cppFlags  "-std=c++17"
+                targets   "fmt"
             }
         }
-        println("Gradle CMake Plugin: ")
         println(externalNativeBuild.cmake.cppFlags)
         println(externalNativeBuild.cmake.arguments)
     }
@@ -69,16 +71,27 @@ android {
     //    neighbor of the top level cmake
     externalNativeBuild {
         cmake {
-            path "../CMakeLists.txt"
+            version "3.10.0+"
+            path "${rootDir}/CMakeLists.txt"
             // buildStagingDirectory "./build"  // Custom path for cmake output
         }
-        //println(cmake.path)
     }
     
     sourceSets{
         // Android Manifest for Gradle
         main {
-            manifest.srcFile 'AndroidManifest.xml'
+            manifest.srcFile "AndroidManifest.xml"
+        }
+    }
+
+    // https://developer.android.com/studio/build/native-dependencies#build_system_configuration
+    buildFeatures {
+        prefab true
+        prefabPublishing true
+    }
+    prefab {
+        fmt {
+            headers "${rootDir}/include"
         }
     }
 }
@@ -88,20 +101,32 @@ assemble.doLast
     // Instead of `ninja install`, Gradle will deploy the files.
     // We are doing this since FMT is dependent to the ANDROID_STL after build
     copy {
-        from 'build/intermediates/cmake'
-        into '../libs'
+        from "build/intermediates/cmake"
+        into "${rootDir}/libs"
     }
     // Copy debug binaries
     copy {
-        from '../libs/debug/obj'
-        into '../libs/debug'
+        from "${rootDir}/libs/debug/obj"
+        into "${rootDir}/libs/debug"
     }
     // Copy Release binaries
     copy {
-        from '../libs/release/obj'
-        into '../libs/release'
+        from "${rootDir}/libs/release/obj"
+        into "${rootDir}/libs/release"
     }
     // Remove empty directory
-    delete '../libs/debug/obj'
-    delete '../libs/release/obj'
+    delete "${rootDir}/libs/debug/obj"
+    delete "${rootDir}/libs/release/obj"
+
+    // Copy AAR files. Notice that the aar is named after the folder of this script.
+    copy {
+        from "build/outputs/aar/support-release.aar"
+        into "${rootDir}/libs"
+        rename "support-release.aar", "fmt-release.aar"
+    }
+    copy {
+        from "build/outputs/aar/support-debug.aar"
+        into "${rootDir}/libs"
+        rename "support-debug.aar", "fmt-debug.aar"
+    }
 }

support/fmt.pro

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

support/manage.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 """Manage site and releases.
 
@@ -163,6 +163,13 @@ def update_site(env):
                 if version.startswith('7.'):
                     b.data = b.data.replace(', std::size_t', ', size_t')
                     b.data = b.data.replace('join(It, It', 'join(It, Sentinel')
+                if version.startswith('7.1.'):
+                    b.data = b.data.replace(', std::size_t', ', size_t')
+                    b.data = b.data.replace('join(It, It', 'join(It, Sentinel')
+                    b.data = b.data.replace(
+                        'fmt::format_to(OutputIt, const S&, Args&&...)',
+                        'fmt::format_to(OutputIt, const S&, Args&&...) -> ' +
+                        'typename std::enable_if<enable, OutputIt>::type')
                 b.data = b.data.replace('aa long', 'a long')
                 b.data = b.data.replace('serveral', 'several')
                 if version.startswith('6.2.'):
@@ -233,7 +240,7 @@ def release(args):
     # Update the version in the changelog.
     title_len = 0
     for line in fileinput.input(changelog_path, inplace=True):
-        if line.decode('utf-8').startswith(version + ' - TBD'):
+        if line.startswith(version + ' - TBD'):
             line = version + ' - ' + datetime.date.today().isoformat()
             title_len = len(line)
             line += '\n'

support/printable.py

@@ -0,0 +1,201 @@
+#!/usr/bin/env python3
+
+# This script is based on
+# https://github.com/rust-lang/rust/blob/master/library/core/src/unicode/printable.py
+# distributed under https://github.com/rust-lang/rust/blob/master/LICENSE-MIT.
+
+# This script uses the following Unicode tables:
+# - UnicodeData.txt
+
+
+from collections import namedtuple
+import csv
+import os
+import subprocess
+
+NUM_CODEPOINTS=0x110000
+
+def to_ranges(iter):
+    current = None
+    for i in iter:
+        if current is None or i != current[1] or i in (0x10000, 0x20000):
+            if current is not None:
+                yield tuple(current)
+            current = [i, i + 1]
+        else:
+            current[1] += 1
+    if current is not None:
+        yield tuple(current)
+
+def get_escaped(codepoints):
+    for c in codepoints:
+        if (c.class_ or "Cn") in "Cc Cf Cs Co Cn Zl Zp Zs".split() and c.value != ord(' '):
+            yield c.value
+
+def get_file(f):
+    try:
+        return open(os.path.basename(f))
+    except FileNotFoundError:
+        subprocess.run(["curl", "-O", f], check=True)
+        return open(os.path.basename(f))
+
+Codepoint = namedtuple('Codepoint', 'value class_')
+
+def get_codepoints(f):
+    r = csv.reader(f, delimiter=";")
+    prev_codepoint = 0
+    class_first = None
+    for row in r:
+        codepoint = int(row[0], 16)
+        name = row[1]
+        class_ = row[2]
+
+        if class_first is not None:
+            if not name.endswith("Last>"):
+                raise ValueError("Missing Last after First")
+
+        for c in range(prev_codepoint + 1, codepoint):
+            yield Codepoint(c, class_first)
+
+        class_first = None
+        if name.endswith("First>"):
+            class_first = class_
+
+        yield Codepoint(codepoint, class_)
+        prev_codepoint = codepoint
+
+    if class_first is not None:
+        raise ValueError("Missing Last after First")
+
+    for c in range(prev_codepoint + 1, NUM_CODEPOINTS):
+        yield Codepoint(c, None)
+
+def compress_singletons(singletons):
+    uppers = [] # (upper, # items in lowers)
+    lowers = []
+
+    for i in singletons:
+        upper = i >> 8
+        lower = i & 0xff
+        if len(uppers) == 0 or uppers[-1][0] != upper:
+            uppers.append((upper, 1))
+        else:
+            upper, count = uppers[-1]
+            uppers[-1] = upper, count + 1
+        lowers.append(lower)
+
+    return uppers, lowers
+
+def compress_normal(normal):
+    # lengths 0x00..0x7f are encoded as 00, 01, ..., 7e, 7f
+    # lengths 0x80..0x7fff are encoded as 80 80, 80 81, ..., ff fe, ff ff
+    compressed = [] # [truelen, (truelenaux), falselen, (falselenaux)]
+
+    prev_start = 0
+    for start, count in normal:
+        truelen = start - prev_start
+        falselen = count
+        prev_start = start + count
+
+        assert truelen < 0x8000 and falselen < 0x8000
+        entry = []
+        if truelen > 0x7f:
+            entry.append(0x80 | (truelen >> 8))
+            entry.append(truelen & 0xff)
+        else:
+            entry.append(truelen & 0x7f)
+        if falselen > 0x7f:
+            entry.append(0x80 | (falselen >> 8))
+            entry.append(falselen & 0xff)
+        else:
+            entry.append(falselen & 0x7f)
+
+        compressed.append(entry)
+
+    return compressed
+
+def print_singletons(uppers, lowers, uppersname, lowersname):
+    print("  static constexpr singleton {}[] = {{".format(uppersname))
+    for u, c in uppers:
+        print("    {{{:#04x}, {}}},".format(u, c))
+    print("  };")
+    print("  static constexpr unsigned char {}[] = {{".format(lowersname))
+    for i in range(0, len(lowers), 8):
+        print("    {}".format(" ".join("{:#04x},".format(l) for l in lowers[i:i+8])))
+    print("  };")
+
+def print_normal(normal, normalname):
+    print("  static constexpr unsigned char {}[] = {{".format(normalname))
+    for v in normal:
+        print("    {}".format(" ".join("{:#04x},".format(i) for i in v)))
+    print("  };")
+
+def main():
+    file = get_file("https://www.unicode.org/Public/UNIDATA/UnicodeData.txt")
+
+    codepoints = get_codepoints(file)
+
+    CUTOFF=0x10000
+    singletons0 = []
+    singletons1 = []
+    normal0 = []
+    normal1 = []
+    extra = []
+
+    for a, b in to_ranges(get_escaped(codepoints)):
+        if a > 2 * CUTOFF:
+            extra.append((a, b - a))
+        elif a == b - 1:
+            if a & CUTOFF:
+                singletons1.append(a & ~CUTOFF)
+            else:
+                singletons0.append(a)
+        elif a == b - 2:
+            if a & CUTOFF:
+                singletons1.append(a & ~CUTOFF)
+                singletons1.append((a + 1) & ~CUTOFF)
+            else:
+                singletons0.append(a)
+                singletons0.append(a + 1)
+        else:
+            if a >= 2 * CUTOFF:
+                extra.append((a, b - a))
+            elif a & CUTOFF:
+                normal1.append((a & ~CUTOFF, b - a))
+            else:
+                normal0.append((a, b - a))
+
+    singletons0u, singletons0l = compress_singletons(singletons0)
+    singletons1u, singletons1l = compress_singletons(singletons1)
+    normal0 = compress_normal(normal0)
+    normal1 = compress_normal(normal1)
+
+    print("""\
+inline auto is_printable(uint32_t cp) -> bool {\
+""")
+    print_singletons(singletons0u, singletons0l, 'singletons0', 'singletons0_lower')
+    print_singletons(singletons1u, singletons1l, 'singletons1', 'singletons1_lower')
+    print_normal(normal0, 'normal0')
+    print_normal(normal1, 'normal1')
+    print("""\
+  auto lower = static_cast<uint16_t>(cp);
+  if (cp < 0x10000) {
+    return is_printable(lower, singletons0,
+                        sizeof(singletons0) / sizeof(*singletons0),
+                        singletons0_lower, normal0, sizeof(normal0));
+  }
+  if (cp < 0x20000) {
+    return is_printable(lower, singletons1,
+                        sizeof(singletons1) / sizeof(*singletons1),
+                        singletons1_lower, normal1, sizeof(normal1));
+  }\
+""")
+    for a, b in extra:
+        print("  if (0x{:x} <= cp && cp < 0x{:x}) return false;".format(a, a + b))
+    print("""\
+  return cp < 0x{:x};
+}}\
+""".format(NUM_CODEPOINTS))
+
+if __name__ == '__main__':
+    main()

support/rst2md.py

@@ -65,7 +65,7 @@ class Translator(nodes.NodeVisitor):
         self.write('\n\n')
 
     def visit_paragraph(self, node):
-        pass
+        self.write('\n\n')
 
     def depart_paragraph(self, node):
         pass

support/travis-build.py

@@ -1,119 +0,0 @@
-#!/usr/bin/env python
-# Build the project on Travis CI.
-
-from __future__ import print_function
-import errno, os, shutil, subprocess, sys, urllib
-from subprocess import call, check_call, Popen, PIPE, STDOUT
-
-def rmtree_if_exists(dir):
-    try:
-        shutil.rmtree(dir)
-    except OSError as e:
-        if e.errno == errno.ENOENT:
-            pass
-
-def makedirs_if_not_exist(dir):
-    try:
-        os.makedirs(dir)
-    except OSError as e:
-        if e.errno != errno.EEXIST:
-            raise
-
-def install_dependencies():
-    branch = os.environ['TRAVIS_BRANCH']
-    if branch != 'master':
-        print('Branch: ' + branch)
-        exit(0) # Ignore non-master branches
-    check_call('curl -s https://deb.nodesource.com/gpgkey/nodesource.gpg.key ' +
-               '| sudo apt-key add -', shell=True)
-    check_call('echo "deb https://deb.nodesource.com/node_0.10 precise main" ' +
-               '| sudo tee /etc/apt/sources.list.d/nodesource.list', shell=True)
-    check_call(['sudo', 'apt-get', 'update'])
-    check_call(['sudo', 'apt-get', 'install', 'python-virtualenv', 'nodejs'])
-    check_call(['sudo', 'npm', 'install', '-g', 'less@2.6.1', 'less-plugin-clean-css'])
-    deb_file = 'doxygen_1.8.6-2_amd64.deb'
-    urllib.urlretrieve('http://mirrors.kernel.org/ubuntu/pool/main/d/doxygen/' +
-                       deb_file, deb_file)
-    check_call(['sudo', 'dpkg', '-i', deb_file])
-
-fmt_dir = os.path.dirname(os.path.dirname(os.path.realpath(__file__)))
-
-build = os.environ['BUILD']
-if build == 'Doc':
-    travis = 'TRAVIS' in os.environ
-    if travis:
-        install_dependencies()
-    sys.path.insert(0, os.path.join(fmt_dir, 'doc'))
-    import build
-    build.create_build_env()
-    html_dir = build.build_docs()
-    repo = 'fmtlib.github.io'
-    if travis and 'KEY' not in os.environ:
-        # Don't update the repo if building on Travis from an account that
-        # doesn't have push access.
-        print('Skipping update of ' + repo)
-        exit(0)
-    # Clone the fmtlib.github.io repo.
-    rmtree_if_exists(repo)
-    git_url = 'https://github.com/' if travis else 'git@github.com:'
-    check_call(['git', 'clone', git_url + 'fmtlib/{}.git'.format(repo)])
-    # Copy docs to the repo.
-    target_dir = os.path.join(repo, 'dev')
-    rmtree_if_exists(target_dir)
-    shutil.copytree(html_dir, target_dir, ignore=shutil.ignore_patterns('.*'))
-    if travis:
-        check_call(['git', 'config', '--global', 'user.name', 'amplbot'])
-        check_call(['git', 'config', '--global', 'user.email', 'viz@ampl.com'])
-    # Push docs to GitHub pages.
-    check_call(['git', 'add', '--all'], cwd=repo)
-    if call(['git', 'diff-index', '--quiet', 'HEAD'], cwd=repo):
-        check_call(['git', 'commit', '-m', 'Update documentation'], cwd=repo)
-        cmd = 'git push'
-        if travis:
-            cmd += ' https://$KEY@github.com/fmtlib/fmtlib.github.io.git master'
-        p = Popen(cmd, shell=True, stdout=PIPE, stderr=STDOUT, cwd=repo)
-        # Print the output without the key.
-        print(p.communicate()[0].replace(os.environ['KEY'], '$KEY'))
-        if p.returncode != 0:
-            raise subprocess.CalledProcessError(p.returncode, cmd)
-    exit(0)
-
-standard = os.environ['STANDARD']
-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 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] +
-           main_cmake_flags, cwd=build_dir)
-
-# Build the library.
-check_call(['cmake', '--build','.'], cwd=build_dir)
-
-# Test the library.
-env = os.environ.copy()
-env['CTEST_OUTPUT_ON_FAILURE'] = '1'
-if call(['make', 'test'], env=env, cwd=build_dir):
-    with open(os.path.join(build_dir, 'Testing', 'Temporary', 'LastTest.log'), 'r') as f:
-        print(f.read())
-    sys.exit(-1)
-
-# Install the library.
-check_call(['make', 'install'], cwd=build_dir)
-
-# Test installation.
-makedirs_if_not_exist(test_build_dir)
-check_call(['cmake', os.path.join(fmt_dir, "test", "find-package-test")] +
-            cmake_flags, cwd=test_build_dir)
-check_call(['make', '-j4'], cwd=test_build_dir)

support/update-coverity-branch.py

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

test/CMakeLists.txt

@@ -1,80 +1,50 @@
-#------------------------------------------------------------------------------
-# Build the google test library
-
-# We compile Google Test ourselves instead of using pre-compiled libraries.
-# See the Google Test FAQ "Why is it not recommended to install a
-# pre-compiled copy of Google Test (for example, into /usr/local)?"
-# at http://code.google.com/p/googletest/wiki/FAQ for more details.
-add_library(gmock STATIC
-  gmock-gtest-all.cc gmock/gmock.h gtest/gtest.h gtest/gtest-spi.h)
-target_compile_definitions(gmock PUBLIC GTEST_HAS_STD_WSTRING=1)
-target_include_directories(gmock SYSTEM PUBLIC . gmock gtest)
-
-find_package(Threads)
-if (Threads_FOUND)
-  target_link_libraries(gmock ${CMAKE_THREAD_LIBS_INIT})
-else ()
-  target_compile_definitions(gmock PUBLIC GTEST_HAS_PTHREAD=0)
-endif ()
-
-target_compile_definitions(gmock PUBLIC GTEST_LANG_CXX11=0)
-
-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.
-if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
-  target_compile_definitions(gmock PUBLIC GTEST_USE_OWN_TR1_TUPLE=1)
-endif ()
-
-# Silence MSVC tr1 deprecation warning in gmock.
-target_compile_definitions(gmock
-  PUBLIC _SILENCE_TR1_NAMESPACE_DEPRECATION_WARNING=1)
-
-#------------------------------------------------------------------------------
-# Build the actual library tests
+add_subdirectory(gtest)
 
 set(TEST_MAIN_SRC test-main.cc gtest-extra.cc gtest-extra.h util.cc)
 add_library(test-main STATIC ${TEST_MAIN_SRC})
-target_include_directories(test-main SYSTEM PUBLIC gtest gmock)
-target_link_libraries(test-main gmock fmt)
+target_include_directories(test-main PUBLIC
+  $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
+target_link_libraries(test-main gtest)
 
 include(CheckCXXCompilerFlag)
 
-# Workaround GTest bug https://github.com/google/googletest/issues/705.
-check_cxx_compiler_flag(
-  -fno-delete-null-pointer-checks HAVE_FNO_DELETE_NULL_POINTER_CHECKS)
-if (HAVE_FNO_DELETE_NULL_POINTER_CHECKS)
-  target_compile_options(test-main PUBLIC -fno-delete-null-pointer-checks)
-endif ()
-
-# Use less strict pedantic flags for the tests because GMock doesn't compile
-# cleanly with -pedantic and -std=c++98.
-if (CMAKE_COMPILER_IS_GNUCXX OR (CMAKE_CXX_COMPILER_ID MATCHES "Clang"))
-    #set(PEDANTIC_COMPILE_FLAGS -Wall -Wextra -Wno-long-long -Wno-variadic-macros)
-endif ()
-
 function(add_fmt_executable name)
   add_executable(${name} ${ARGN})
   if (MINGW)
     target_link_libraries(${name} -static-libgcc -static-libstdc++)
   endif ()
+  # (Wstringop-overflow) - [meta-bug] bogus/missing -Wstringop-overflow warnings
+  #   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88443
+  # Bogus -Wstringop-overflow warning
+  #   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100395
+  # [10 Regression] spurious -Wstringop-overflow writing to a trailing array plus offset
+  #   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95353
+  if (CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND
+      NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 7.0)
+    target_link_libraries(${name} -Wno-stringop-overflow)
+  endif ()
 endfunction()
 
 # Adds a test.
 # Usage: add_fmt_test(name srcs...)
 function(add_fmt_test name)
-  add_fmt_executable(${name} ${name}.cc ${ARGN})
-  target_link_libraries(${name} test-main)
+  cmake_parse_arguments(ADD_FMT_TEST "HEADER_ONLY;MODULE" "" "" ${ARGN})
+
+  set(sources ${name}.cc ${ADD_FMT_TEST_UNPARSED_ARGUMENTS})
+  if (ADD_FMT_TEST_HEADER_ONLY)
+    set(sources ${sources} ${TEST_MAIN_SRC} ../src/os.cc)
+    set(libs gtest fmt-header-only)
+    if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wno-weak-vtables)
+    endif ()
+  elseif (ADD_FMT_TEST_MODULE)
+    set(libs gtest test-module)
+    set_source_files_properties(${name}.cc PROPERTIES OBJECT_DEPENDS test-module)
+  else ()
+    set(libs test-main fmt)
+  endif ()
+  add_fmt_executable(${name} ${sources})
+  target_link_libraries(${name} ${libs})
 
   # Define if certain C++ features can be used.
   if (FMT_PEDANTIC)
@@ -83,39 +53,78 @@ function(add_fmt_test name)
   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(args-test)
 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 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)
+  add_fmt_test(format-impl-test HEADER_ONLY header-only-test.cc)
 endif ()
-add_fmt_test(locale-test)
 add_fmt_test(ostream-test)
 add_fmt_test(compile-test)
+add_fmt_test(compile-fp-test HEADER_ONLY)
+if (MSVC)
+  # Without this option, MSVC returns 199711L for the __cplusplus macro.
+  target_compile_options(compile-fp-test PRIVATE /Zc:__cplusplus)
+endif()
 add_fmt_test(printf-test)
-add_fmt_test(custom-formatter-test)
-add_fmt_test(ranges-test)
+add_fmt_test(ranges-test ranges-odr-test.cc)
 add_fmt_test(scan-test)
+add_fmt_test(unicode-test HEADER_ONLY)
+if (MSVC)
+  target_compile_options(unicode-test PRIVATE /utf-8)
+endif ()
+add_fmt_test(xchar-test)
+add_fmt_test(enforce-checks-test)
+target_compile_definitions(enforce-checks-test PRIVATE
+                           -DFMT_ENFORCE_COMPILE_STRING)
 
-if (NOT MSVC_BUILD_STATIC)
+if (FMT_CAN_MODULE)
+  # The tests need {fmt} to be compiled as traditional library
+  # because of visibility of implementation details.
+  # If module support is present the module tests require a
+  # test-only module to be built from {fmt}
+  add_library(test-module OBJECT ${CMAKE_SOURCE_DIR}/src/fmt.cc)
+  target_compile_features(test-module PUBLIC ${FMT_REQUIRED_FEATURES})
+  target_include_directories(test-module PUBLIC
+    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
+  enable_module(test-module)
+
+  add_fmt_test(module-test MODULE test-main.cc)
+  if (MSVC)
+    target_compile_options(test-module PRIVATE /utf-8 /Zc:__cplusplus
+                           /Zc:externConstexpr /Zc:inline)
+    target_compile_options(module-test PRIVATE /utf-8 /Zc:__cplusplus
+                           /Zc:externConstexpr /Zc:inline)
+  endif ()
+endif ()
+
+if (NOT DEFINED MSVC_STATIC_RUNTIME AND MSVC)
+  foreach (flag_var
+			 CMAKE_CXX_FLAGS CMAKE_CXX_FLAGS_DEBUG CMAKE_CXX_FLAGS_RELEASE
+			 CMAKE_CXX_FLAGS_MINSIZEREL CMAKE_CXX_FLAGS_RELWITHDEBINFO)
+	if (${flag_var} MATCHES "^(/|-)(MT|MTd)")
+	  set(MSVC_STATIC_RUNTIME ON)
+	  break()
+	endif()
+  endforeach()
+endif()
+
+if (NOT MSVC_STATIC_RUNTIME)
   add_fmt_executable(posix-mock-test
     posix-mock-test.cc ../src/format.cc ${TEST_MAIN_SRC})
   target_include_directories(
     posix-mock-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
-  target_link_libraries(posix-mock-test gmock)
-  target_include_directories(posix-mock-test SYSTEM PUBLIC gtest gmock)
+  target_link_libraries(posix-mock-test gtest)
   if (FMT_PEDANTIC)
     target_compile_options(posix-mock-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
   endif ()
@@ -126,34 +135,16 @@ if (NOT MSVC_BUILD_STATIC)
   add_fmt_test(os-test)
 endif ()
 
-add_fmt_executable(header-only-test
-  header-only-test.cc header-only-test2.cc test-main.cc)
-target_link_libraries(header-only-test gmock)
-target_include_directories(header-only-test SYSTEM PUBLIC gtest gmock)
-if (TARGET fmt-header-only)
-  target_link_libraries(header-only-test fmt-header-only)
-else ()
-  target_include_directories(
-    header-only-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
-  target_compile_definitions(header-only-test PRIVATE FMT_HEADER_ONLY=1)
-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)
+    add_library(noexception-test ../src/format.cc noexception-test.cc)
     target_include_directories(
       noexception-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
     target_compile_options(noexception-test PRIVATE -fno-exceptions)
@@ -168,7 +159,11 @@ if (FMT_PEDANTIC)
     nolocale-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
   target_compile_definitions(
     nolocale-test PRIVATE FMT_STATIC_THOUSANDS_SEPARATOR=1)
+endif ()
 
+# These tests are disabled on Windows because they take too long.
+if (FMT_PEDANTIC AND NOT WIN32)
+  # Test if incorrect API usages produce compilation error.
   add_test(compile-error-test ${CMAKE_CTEST_COMMAND}
     --build-and-test
     "${CMAKE_CURRENT_SOURCE_DIR}/compile-error-test"
@@ -177,14 +172,11 @@ if (FMT_PEDANTIC)
     --build-makeprogram ${CMAKE_MAKE_PROGRAM}
     --build-options
     "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
+    "-DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}"
     "-DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}"
-    "-DCXX_STANDARD_FLAG=${CXX_STANDARD_FLAG}"
-    "-DPEDANTIC_COMPILE_FLAGS=${PEDANTIC_COMPILE_FLAGS}"
+    "-DFMT_DIR=${CMAKE_SOURCE_DIR}"
     "-DSUPPORTS_USER_DEFINED_LITERALS=${SUPPORTS_USER_DEFINED_LITERALS}")
-endif ()
 
-# 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}
@@ -195,6 +187,7 @@ if (FMT_PEDANTIC AND NOT WIN32)
     --build-makeprogram ${CMAKE_MAKE_PROGRAM}
     --build-options
     "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
+    "-DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}"
     "-DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}"
     "-DFMT_DIR=${PROJECT_BINARY_DIR}"
     "-DPEDANTIC_COMPILE_FLAGS=${PEDANTIC_COMPILE_FLAGS}"
@@ -215,6 +208,21 @@ if (FMT_PEDANTIC AND NOT WIN32)
     "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}")
 endif ()
 
+# This test are disabled on Windows because it is only *NIX issue.
+if (FMT_PEDANTIC AND NOT WIN32)
+  add_test(static-export-test ${CMAKE_CTEST_COMMAND}
+    -C ${CMAKE_BUILD_TYPE}
+    --build-and-test
+    "${CMAKE_CURRENT_SOURCE_DIR}/static-export-test"
+    "${CMAKE_CURRENT_BINARY_DIR}/static-export-test"
+    --build-generator ${CMAKE_GENERATOR}
+    --build-makeprogram ${CMAKE_MAKE_PROGRAM}
+    --build-options
+    "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
+    "-DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}"
+    "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}")
+endif ()
+
 # Activate optional CUDA tests if CUDA is found. For version selection see
 # https://docs.nvidia.com/cuda/cuda-c-programming-guide/index.html#cpp14-language-features
 if (FMT_CUDA_TEST)

test/add-subdirectory-test/CMakeLists.txt

@@ -1,17 +1,17 @@
-cmake_minimum_required(VERSION 3.1.0)
+cmake_minimum_required(VERSION 3.1...3.18)
 
-project(fmt-test)
+project(fmt-test CXX)
 
 add_subdirectory(../.. fmt)
 
-add_executable(library-test "main.cc")
-target_link_libraries(library-test fmt::fmt)
-target_compile_options(library-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
+add_executable(library-test main.cc)
 target_include_directories(library-test PUBLIC SYSTEM .)
+target_compile_options(library-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
+target_link_libraries(library-test fmt::fmt)
 
 if (TARGET fmt::fmt-header-only)
-  add_executable(header-only-test "main.cc")
-  target_link_libraries(header-only-test fmt::fmt-header-only)
-  target_compile_options(header-only-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
+  add_executable(header-only-test main.cc)
   target_include_directories(header-only-test PUBLIC SYSTEM .)
+  target_compile_options(header-only-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
+  target_link_libraries(header-only-test fmt::fmt-header-only)
 endif ()

test/add-subdirectory-test/main.cc

@@ -1,6 +1,5 @@
-#include "fmt/format.h"
+#include "fmt/core.h"
 
 int main(int argc, char** argv) {
-  for(int i = 0; i < argc; ++i)
-    fmt::print("{}: {}\n", i, argv[i]);
+  for (int i = 0; i < argc; ++i) fmt::print("{}: {}\n", i, argv[i]);
 }

test/args-test.cc

@@ -0,0 +1,186 @@
+// Formatting library for C++ - dynamic argument store tests
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include "fmt/args.h"
+
+#include <memory>
+
+#include "gtest/gtest.h"
+
+TEST(args_test, basic) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  store.push_back(42);
+  store.push_back("abc1");
+  store.push_back(1.5f);
+  EXPECT_EQ("42 and abc1 and 1.5", fmt::vformat("{} and {} and {}", store));
+}
+
+TEST(args_test, strings_and_refs) {
+  // Unfortunately the tests are compiled with old ABI so strings use COW.
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  char str[] = "1234567890";
+  store.push_back(str);
+  store.push_back(std::cref(str));
+  store.push_back(fmt::string_view{str});
+  str[0] = 'X';
+
+  auto result = fmt::vformat("{} and {} and {}", store);
+  EXPECT_EQ("1234567890 and X234567890 and X234567890", result);
+}
+
+struct custom_type {
+  int i = 0;
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<custom_type> {
+  auto parse(format_parse_context& ctx) const -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const custom_type& p, FormatContext& ctx) -> decltype(ctx.out()) {
+    return format_to(ctx.out(), "cust={}", p.i);
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(args_test, custom_format) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  auto c = custom_type();
+  store.push_back(c);
+  ++c.i;
+  store.push_back(c);
+  ++c.i;
+  store.push_back(std::cref(c));
+  ++c.i;
+  auto result = fmt::vformat("{} and {} and {}", store);
+  EXPECT_EQ("cust=0 and cust=1 and cust=3", result);
+}
+
+struct to_stringable {
+  friend fmt::string_view to_string_view(to_stringable) { return {}; }
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<to_stringable> {
+  auto parse(format_parse_context& ctx) const -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  auto format(to_stringable, format_context& ctx) -> decltype(ctx.out()) {
+    return ctx.out();
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(args_test, to_string_and_formatter) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  auto s = to_stringable();
+  store.push_back(s);
+  store.push_back(std::cref(s));
+  fmt::vformat("", store);
+}
+
+TEST(args_test, named_int) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  store.push_back(fmt::arg("a1", 42));
+  EXPECT_EQ("42", fmt::vformat("{a1}", store));
+}
+
+TEST(args_test, named_strings) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  char str[] = "1234567890";
+  store.push_back(fmt::arg("a1", str));
+  store.push_back(fmt::arg("a2", std::cref(str)));
+  str[0] = 'X';
+  EXPECT_EQ("1234567890 and X234567890", fmt::vformat("{a1} and {a2}", store));
+}
+
+TEST(args_test, named_arg_by_ref) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  char band[] = "Rolling Stones";
+  store.push_back(fmt::arg("band", std::cref(band)));
+  band[9] = 'c';  // Changing band affects the output.
+  EXPECT_EQ(fmt::vformat("{band}", store), "Rolling Scones");
+}
+
+TEST(args_test, named_custom_format) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  auto c = custom_type();
+  store.push_back(fmt::arg("c1", c));
+  ++c.i;
+  store.push_back(fmt::arg("c2", c));
+  ++c.i;
+  store.push_back(fmt::arg("c_ref", std::cref(c)));
+  ++c.i;
+  auto result = fmt::vformat("{c1} and {c2} and {c_ref}", store);
+  EXPECT_EQ("cust=0 and cust=1 and cust=3", result);
+}
+
+TEST(args_test, clear) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  store.push_back(42);
+
+  auto result = fmt::vformat("{}", store);
+  EXPECT_EQ("42", result);
+
+  store.push_back(43);
+  result = fmt::vformat("{} and {}", store);
+  EXPECT_EQ("42 and 43", result);
+
+  store.clear();
+  store.push_back(44);
+  result = fmt::vformat("{}", store);
+  EXPECT_EQ("44", result);
+}
+
+TEST(args_test, reserve) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  store.reserve(2, 1);
+  store.push_back(1.5f);
+  store.push_back(fmt::arg("a1", 42));
+  auto result = fmt::vformat("{a1} and {}", store);
+  EXPECT_EQ("42 and 1.5", result);
+}
+
+struct copy_throwable {
+  copy_throwable() {}
+  copy_throwable(const copy_throwable&) { throw "deal with it"; }
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<copy_throwable> {
+  auto parse(format_parse_context& ctx) const -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+  auto format(copy_throwable, format_context& ctx) -> decltype(ctx.out()) {
+    return ctx.out();
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(args_test, throw_on_copy) {
+  fmt::dynamic_format_arg_store<fmt::format_context> store;
+  store.push_back(std::string("foo"));
+  try {
+    store.push_back(copy_throwable());
+  } catch (...) {
+  }
+  EXPECT_EQ(fmt::vformat("{}", store), "foo");
+}
+
+TEST(args_test, move_constructor) {
+  using store_type = fmt::dynamic_format_arg_store<fmt::format_context>;
+  auto store = std::unique_ptr<store_type>(new store_type());
+  store->push_back(42);
+  store->push_back(std::string("foo"));
+  store->push_back(fmt::arg("a1", "foo"));
+  auto moved_store = std::move(*store);
+  store.reset();
+  EXPECT_EQ(fmt::vformat("{} {} {a1}", moved_store), "42 foo foo");
+}

test/assert-test.cc

@@ -1,4 +1,8 @@
-// Formatting library for C++ - assertion tests
+// Formatting library for C++ - FMT_ASSERT test
+//
+// It is a separate test to minimize the number of EXPECT_DEBUG_DEATH checks
+// which are slow on some platforms. In other tests FMT_ASSERT is made to throw
+// an exception which is much faster and easier to check.
 //
 // Copyright (c) 2012 - present, Victor Zverovich
 // All rights reserved.
@@ -6,9 +10,9 @@
 // For the license information refer to format.h.
 
 #include "fmt/core.h"
-#include "gtest.h"
+#include "gtest/gtest.h"
 
-TEST(AssertTest, Fail) {
+TEST(assert_test, fail) {
 #if GTEST_HAS_DEATH_TEST
   EXPECT_DEBUG_DEATH(FMT_ASSERT(false, "don't panic!"), "don't panic!");
 #else
@@ -16,9 +20,8 @@ TEST(AssertTest, Fail) {
 #endif
 }
 
-bool test_condition = false;
-
-TEST(AssertTest, DanglingElse) {
+TEST(assert_test, dangling_else) {
+  bool test_condition = false;
   bool executed_else = false;
   if (test_condition)
     FMT_ASSERT(true, "");

test/chrono-test.cc

@@ -5,77 +5,221 @@
 //
 // For the license information refer to format.h.
 
-#ifdef WIN32
-#  define _CRT_SECURE_NO_WARNINGS
-#endif
-
 #include "fmt/chrono.h"
 
-#include <iomanip>
+#include <ctime>
+#include <vector>
 
-#include "gtest-extra.h"
+#include "gtest-extra.h"  // EXPECT_THROW_MSG
+#include "util.h"         // get_locale
 
-std::tm make_tm() {
+using fmt::runtime;
+
+using testing::Contains;
+
+auto make_tm() -> std::tm {
   auto time = std::tm();
   time.tm_mday = 1;
   return time;
 }
 
-std::tm make_hour(int h) {
+auto make_hour(int h) -> std::tm {
   auto time = make_tm();
   time.tm_hour = h;
   return time;
 }
 
-std::tm make_minute(int m) {
+auto make_minute(int m) -> std::tm {
   auto time = make_tm();
   time.tm_min = m;
   return time;
 }
 
-std::tm make_second(int s) {
+auto make_second(int s) -> std::tm {
   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) {
+std::string system_strftime(const std::string& format, const std::tm* timeptr,
+                            std::locale* locptr = nullptr) {
+  auto loc = locptr ? *locptr : std::locale::classic();
   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));
+  facet.put(os, os, ' ', timeptr, format.c_str(),
+            format.c_str() + format.size());
+#ifdef _WIN32
+  // Workaround a bug in older versions of Universal CRT.
+  auto str = os.str();
+  if (str == "-0000") str = "+0000";
+  return str;
+#else
   return os.str();
+#endif
 }
 
-TEST(TimeTest, Format) {
-  std::tm tm = std::tm();
+FMT_CONSTEXPR std::tm make_tm(int year, int mon, int mday, int hour, int min,
+                              int sec) {
+  auto tm = std::tm();
+  tm.tm_sec = sec;
+  tm.tm_min = min;
+  tm.tm_hour = hour;
+  tm.tm_mday = mday;
+  tm.tm_mon = mon - 1;
+  tm.tm_year = year - 1900;
+  return tm;
+}
+
+TEST(chrono_test, format_tm) {
+  auto 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));
+  tm.tm_hour = 11;
+  tm.tm_min = 22;
+  tm.tm_sec = 33;
+  EXPECT_EQ(fmt::format("The date is {:%Y-%m-%d %H:%M:%S}.", tm),
+            "The date is 2016-04-25 11:22:33.");
+  EXPECT_EQ(fmt::format("{:%Y}", tm), "2016");
+  EXPECT_EQ(fmt::format("{:%C}", tm), "20");
+  EXPECT_EQ(fmt::format("{:%C%y}", tm), fmt::format("{:%Y}", tm));
+  EXPECT_EQ(fmt::format("{:%e}", tm), "25");
+  EXPECT_EQ(fmt::format("{:%D}", tm), "04/25/16");
+  EXPECT_EQ(fmt::format("{:%F}", tm), "2016-04-25");
+  EXPECT_EQ(fmt::format("{:%T}", tm), "11:22:33");
+
+  // Short year
+  tm.tm_year = 999 - 1900;
+  tm.tm_mon = 0;   // for %G
+  tm.tm_mday = 2;  // for %G
+  tm.tm_wday = 3;  // for %G
+  tm.tm_yday = 1;  // for %G
+  EXPECT_EQ(fmt::format("{:%Y}", tm), "0999");
+  EXPECT_EQ(fmt::format("{:%C%y}", tm), "0999");
+  EXPECT_EQ(fmt::format("{:%G}", tm), "0999");
+
+  tm.tm_year = 27 - 1900;
+  EXPECT_EQ(fmt::format("{:%Y}", tm), "0027");
+  EXPECT_EQ(fmt::format("{:%C%y}", tm), "0027");
+
+  // Overflow year
+  tm.tm_year = 2147483647;
+  EXPECT_EQ(fmt::format("{:%Y}", tm), "2147485547");
+
+  tm.tm_year = -2147483648;
+  EXPECT_EQ(fmt::format("{:%Y}", tm), "-2147481748");
+
+  // for week on the year
+  // https://www.cl.cam.ac.uk/~mgk25/iso-time.html
+  std::vector<std::tm> tm_list = {
+      make_tm(1975, 12, 29, 12, 14, 16),  // W01
+      make_tm(1977, 1, 2, 12, 14, 16),    // W53
+      make_tm(1999, 12, 27, 12, 14, 16),  // W52
+      make_tm(1999, 12, 31, 12, 14, 16),  // W52
+      make_tm(2000, 1, 1, 12, 14, 16),    // W52
+      make_tm(2000, 1, 2, 12, 14, 16),    // W52
+      make_tm(2000, 1, 3, 12, 14, 16)     // W1
+  };
+  const std::string iso_week_spec = "%Y-%m-%d: %G %g %V";
+  for (auto ctm : tm_list) {
+    // Calculate tm_yday, tm_wday, etc.
+    std::time_t t = std::mktime(&ctm);
+    tm = *std::localtime(&t);
+
+    auto fmt_spec = fmt::format("{{:{}}}", iso_week_spec);
+    EXPECT_EQ(system_strftime(iso_week_spec, &tm),
+              fmt::format(fmt::runtime(fmt_spec), tm));
+  }
+
+  // Every day from 1970-01-01
+  std::time_t time_now = std::time(nullptr);
+  for (std::time_t t = 6 * 3600; t < time_now; t += 86400) {
+    tm = *std::localtime(&t);
+
+    auto fmt_spec = fmt::format("{{:{}}}", iso_week_spec);
+    EXPECT_EQ(system_strftime(iso_week_spec, &tm),
+              fmt::format(fmt::runtime(fmt_spec), tm));
+  }
 }
 
-TEST(TimeTest, GrowBuffer) {
-  std::string s = "{:";
+// MSVC:
+//  minkernel\crts\ucrt\src\appcrt\time\wcsftime.cpp(971) : Assertion failed:
+//  timeptr->tm_year >= -1900 && timeptr->tm_year <= 8099
+#ifndef _WIN32
+TEST(chrono_test, format_tm_future) {
+  auto tm = std::tm();
+  tm.tm_year = 10445;  // 10000+ years
+  tm.tm_mon = 3;
+  tm.tm_mday = 25;
+  tm.tm_hour = 11;
+  tm.tm_min = 22;
+  tm.tm_sec = 33;
+  EXPECT_EQ(fmt::format("The date is {:%Y-%m-%d %H:%M:%S}.", tm),
+            "The date is 12345-04-25 11:22:33.");
+  EXPECT_EQ(fmt::format("{:%Y}", tm), "12345");
+  EXPECT_EQ(fmt::format("{:%C}", tm), "123");
+  EXPECT_EQ(fmt::format("{:%C%y}", tm), fmt::format("{:%Y}", tm));
+  EXPECT_EQ(fmt::format("{:%D}", tm), "04/25/45");
+  EXPECT_EQ(fmt::format("{:%F}", tm), "12345-04-25");
+  EXPECT_EQ(fmt::format("{:%T}", tm), "11:22:33");
+}
+
+TEST(chrono_test, format_tm_past) {
+  auto tm = std::tm();
+  tm.tm_year = -2001;
+  tm.tm_mon = 3;
+  tm.tm_mday = 25;
+  tm.tm_hour = 11;
+  tm.tm_min = 22;
+  tm.tm_sec = 33;
+  EXPECT_EQ(fmt::format("The date is {:%Y-%m-%d %H:%M:%S}.", tm),
+            "The date is -101-04-25 11:22:33.");
+  EXPECT_EQ(fmt::format("{:%Y}", tm), "-101");
+
+  // macOS  %C - "-1"
+  // Linux  %C - "-2"
+  // fmt    %C - "-1"
+  EXPECT_EQ(fmt::format("{:%C}", tm), "-1");
+  EXPECT_EQ(fmt::format("{:%C%y}", tm), fmt::format("{:%Y}", tm));
+
+  // macOS  %D - "04/25/01" (%y)
+  // Linux  %D - "04/25/99" (%y)
+  // fmt    %D - "04/25/01" (%y)
+  EXPECT_EQ(fmt::format("{:%D}", tm), "04/25/01");
+
+  EXPECT_EQ(fmt::format("{:%F}", tm), "-101-04-25");
+  EXPECT_EQ(fmt::format("{:%T}", tm), "11:22:33");
+
+  tm.tm_year = -1901;  // -1
+  EXPECT_EQ(fmt::format("{:%Y}", tm), "-001");
+  EXPECT_EQ(fmt::format("{:%C%y}", tm), fmt::format("{:%Y}", tm));
+
+  tm.tm_year = -1911;  // -11
+  EXPECT_EQ(fmt::format("{:%Y}", tm), "-011");
+  EXPECT_EQ(fmt::format("{:%C%y}", tm), fmt::format("{:%Y}", tm));
+}
+#endif
+
+TEST(chrono_test, grow_buffer) {
+  auto s = std::string("{:");
   for (int i = 0; i < 30; ++i) s += "%c";
   s += "}\n";
-  std::time_t t = std::time(nullptr);
-  fmt::format(s, *std::localtime(&t));
+  auto t = std::time(nullptr);
+  (void)fmt::format(fmt::runtime(s), *std::localtime(&t));
 }
 
-TEST(TimeTest, FormatToEmptyContainer) {
-  std::string s;
+TEST(chrono_test, format_to_empty_container) {
   auto time = std::tm();
   time.tm_sec = 42;
+  auto s = std::string();
   fmt::format_to(std::back_inserter(s), "{:%S}", time);
   EXPECT_EQ(s, "42");
 }
 
-TEST(TimeTest, EmptyResult) { EXPECT_EQ("", fmt::format("{}", std::tm())); }
+TEST(chrono_test, empty_result) { EXPECT_EQ(fmt::format("{}", std::tm()), ""); }
 
-static bool EqualTime(const std::tm& lhs, const std::tm& rhs) {
+auto equal(const std::tm& lhs, const std::tm& rhs) -> bool {
   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 &&
@@ -83,28 +227,62 @@ static bool EqualTime(const std::tm& lhs, const std::tm& rhs) {
          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(chrono_test, localtime) {
+  auto t = std::time(nullptr);
+  auto tm = *std::localtime(&t);
+  EXPECT_TRUE(equal(tm, fmt::localtime(t)));
 }
 
-TEST(TimeTest, GMTime) {
-  std::time_t t = std::time(nullptr);
-  std::tm tm = *std::gmtime(&t);
-  EXPECT_TRUE(EqualTime(tm, fmt::gmtime(t)));
+TEST(chrono_test, gmtime) {
+  auto t = std::time(nullptr);
+  auto tm = *std::gmtime(&t);
+  EXPECT_TRUE(equal(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)); \
+template <typename TimePoint> auto strftime_full(TimePoint tp) -> std::string {
+  auto t = std::chrono::system_clock::to_time_t(tp);
+  auto tm = *std::localtime(&t);
+  return system_strftime("%Y-%m-%d %H:%M:%S", &tm);
+}
+
+TEST(chrono_test, time_point) {
+  auto t1 = std::chrono::system_clock::now();
+  EXPECT_EQ(strftime_full(t1), fmt::format("{:%Y-%m-%d %H:%M:%S}", t1));
+  EXPECT_EQ(strftime_full(t1), fmt::format("{}", t1));
+  using time_point =
+      std::chrono::time_point<std::chrono::system_clock, std::chrono::seconds>;
+  auto t2 = time_point(std::chrono::seconds(42));
+  EXPECT_EQ(strftime_full(t2), fmt::format("{:%Y-%m-%d %H:%M:%S}", t2));
+
+  std::vector<std::string> spec_list = {
+      "%%",  "%n",  "%t",  "%Y",  "%EY", "%y",  "%Oy", "%Ey", "%C",
+      "%EC", "%G",  "%g",  "%b",  "%h",  "%B",  "%m",  "%Om", "%U",
+      "%OU", "%W",  "%OW", "%V",  "%OV", "%j",  "%d",  "%Od", "%e",
+      "%Oe", "%a",  "%A",  "%w",  "%Ow", "%u",  "%Ou", "%H",  "%OH",
+      "%I",  "%OI", "%M",  "%OM", "%S",  "%OS", "%x",  "%Ex", "%X",
+      "%EX", "%D",  "%F",  "%R",  "%T",  "%p",  "%z",  "%Z"};
+  spec_list.push_back("%Y-%m-%d %H:%M:%S");
+#ifndef _WIN32
+  // Disabled on Windows because these formats are not consistent among
+  // platforms.
+  spec_list.insert(spec_list.end(), {"%c", "%Ec", "%r"});
+#endif
+
+  for (const auto& spec : spec_list) {
+    auto t = std::chrono::system_clock::to_time_t(t1);
+    auto tm = *std::localtime(&t);
+
+    auto sys_output = system_strftime(spec, &tm);
+
+    auto fmt_spec = fmt::format("{{:{}}}", spec);
+    EXPECT_EQ(sys_output, fmt::format(fmt::runtime(fmt_spec), t1));
+    EXPECT_EQ(sys_output, fmt::format(fmt::runtime(fmt_spec), tm));
   }
+}
 
 #ifndef FMT_STATIC_THOUSANDS_SEPARATOR
 
-TEST(ChronoTest, FormatDefault) {
+TEST(chrono_test, format_default) {
   EXPECT_EQ("42s", fmt::format("{}", std::chrono::seconds(42)));
   EXPECT_EQ("42as",
             fmt::format("{}", std::chrono::duration<int, std::atto>(42)));
@@ -146,49 +324,7 @@ TEST(ChronoTest, FormatDefault) {
       fmt::format("{}", std::chrono::duration<int, std::ratio<15, 4>>(42)));
 }
 
-TEST(ChronoTest, FormatWide) {
-  EXPECT_EQ(L"42s", fmt::format(L"{}", std::chrono::seconds(42)));
-  EXPECT_EQ(L"42as",
-            fmt::format(L"{}", std::chrono::duration<int, std::atto>(42)));
-  EXPECT_EQ(L"42fs",
-            fmt::format(L"{}", std::chrono::duration<int, std::femto>(42)));
-  EXPECT_EQ(L"42ps",
-            fmt::format(L"{}", std::chrono::duration<int, std::pico>(42)));
-  EXPECT_EQ(L"42ns", fmt::format(L"{}", std::chrono::nanoseconds(42)));
-  EXPECT_EQ(L"42\u00B5s", fmt::format(L"{}", std::chrono::microseconds(42)));
-  EXPECT_EQ(L"42ms", fmt::format(L"{}", std::chrono::milliseconds(42)));
-  EXPECT_EQ(L"42cs",
-            fmt::format(L"{}", std::chrono::duration<int, std::centi>(42)));
-  EXPECT_EQ(L"42ds",
-            fmt::format(L"{}", std::chrono::duration<int, std::deci>(42)));
-  EXPECT_EQ(L"42s", fmt::format(L"{}", std::chrono::seconds(42)));
-  EXPECT_EQ(L"42das",
-            fmt::format(L"{}", std::chrono::duration<int, std::deca>(42)));
-  EXPECT_EQ(L"42hs",
-            fmt::format(L"{}", std::chrono::duration<int, std::hecto>(42)));
-  EXPECT_EQ(L"42ks",
-            fmt::format(L"{}", std::chrono::duration<int, std::kilo>(42)));
-  EXPECT_EQ(L"42Ms",
-            fmt::format(L"{}", std::chrono::duration<int, std::mega>(42)));
-  EXPECT_EQ(L"42Gs",
-            fmt::format(L"{}", std::chrono::duration<int, std::giga>(42)));
-  EXPECT_EQ(L"42Ts",
-            fmt::format(L"{}", std::chrono::duration<int, std::tera>(42)));
-  EXPECT_EQ(L"42Ps",
-            fmt::format(L"{}", std::chrono::duration<int, std::peta>(42)));
-  EXPECT_EQ(L"42Es",
-            fmt::format(L"{}", std::chrono::duration<int, std::exa>(42)));
-  EXPECT_EQ(L"42m", fmt::format(L"{}", std::chrono::minutes(42)));
-  EXPECT_EQ(L"42h", fmt::format(L"{}", std::chrono::hours(42)));
-  EXPECT_EQ(
-      L"42[15]s",
-      fmt::format(L"{}", std::chrono::duration<int, std::ratio<15, 1>>(42)));
-  EXPECT_EQ(
-      L"42[15/4]s",
-      fmt::format(L"{}", std::chrono::duration<int, std::ratio<15, 4>>(42)));
-}
-
-TEST(ChronoTest, Align) {
+TEST(chrono_test, align) {
   auto s = std::chrono::seconds(42);
   EXPECT_EQ("42s  ", fmt::format("{:5}", s));
   EXPECT_EQ("42s  ", fmt::format("{:{}}", s, 5));
@@ -204,7 +340,7 @@ TEST(ChronoTest, Align) {
             fmt::format("{:{}%H:%M:%S}", std::chrono::seconds(12345), 12));
 }
 
-TEST(ChronoTest, FormatSpecs) {
+TEST(chrono_test, format_specs) {
   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)));
@@ -233,43 +369,64 @@ TEST(ChronoTest, FormatSpecs) {
   EXPECT_EQ("s", fmt::format("{:%q}", std::chrono::seconds(12345)));
 }
 
-TEST(ChronoTest, InvalidSpecs) {
+TEST(chrono_test, invalid_specs) {
   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,
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%a}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%A}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%c}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%x}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%Ex}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%X}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%EX}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%D}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%F}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%Ec}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%w}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%u}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%b}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%B}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%z}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%Z}"), sec), fmt::format_error,
+                   "no date");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%Eq}"), sec), fmt::format_error,
                    "invalid format");
-  EXPECT_THROW_MSG(fmt::format("{:%Oq}", sec), fmt::format_error,
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%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;
-  }
+auto format_tm(const std::tm& time, fmt::string_view spec,
+               const std::locale& loc) -> std::string {
+  auto& facet = std::use_facet<std::time_put<char>>(loc);
+  std::ostringstream os;
+  os.imbue(loc);
+  facet.put(os, os, ' ', &time, spec.begin(), spec.end());
+  return os.str();
+}
+
+TEST(chrono_test, locale) {
+  auto loc = get_locale("ja_JP.utf8");
+  if (loc == std::locale::classic()) return;
+#  define EXPECT_TIME(spec, time, duration)                     \
+    {                                                           \
+      auto jp_loc = std::locale("ja_JP.utf8");                  \
+      EXPECT_EQ(format_tm(time, spec, jp_loc),                  \
+                fmt::format(jp_loc, "{:L" spec "}", duration)); \
+    }
   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));
@@ -283,9 +440,9 @@ TEST(ChronoTest, Locale) {
   EXPECT_TIME("%p", time, sec);
 }
 
-typedef std::chrono::duration<double, std::milli> dms;
+using dms = std::chrono::duration<double, std::milli>;
 
-TEST(ChronoTest, FormatDefaultFP) {
+TEST(chrono_test, format_default_fp) {
   typedef std::chrono::duration<float> fs;
   EXPECT_EQ("1.234s", fmt::format("{}", fs(1.234)));
   typedef std::chrono::duration<float, std::milli> fms;
@@ -295,24 +452,37 @@ TEST(ChronoTest, FormatDefaultFP) {
   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");
+TEST(chrono_test, format_precision) {
+  EXPECT_THROW_MSG(
+      (void)fmt::format(runtime("{:.2}"), std::chrono::seconds(42)),
+      fmt::format_error, "precision not allowed for this argument type");
+  EXPECT_EQ("1ms", fmt::format("{:.0}", dms(1.234)));
   EXPECT_EQ("1.2ms", fmt::format("{:.1}", dms(1.234)));
   EXPECT_EQ("1.23ms", fmt::format("{:.{}}", dms(1.234), 2));
+
+  EXPECT_EQ("13ms", fmt::format("{:.0}", dms(12.56)));
+  EXPECT_EQ("12.6ms", fmt::format("{:.1}", dms(12.56)));
+  EXPECT_EQ("12.56ms", fmt::format("{:.2}", dms(12.56)));
 }
 
-TEST(ChronoTest, FormatFullSpecs) {
+TEST(chrono_test, format_full_specs) {
+  EXPECT_EQ("1ms   ", fmt::format("{:6.0}", dms(1.234)));
   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)));
+
+  EXPECT_EQ("13ms  ", fmt::format("{:6.0}", dms(12.56)));
+  EXPECT_EQ("    13ms", fmt::format("{:>8.{}}", dms(12.56), 0));
+  EXPECT_EQ(" 13ms ", fmt::format("{:^{}.{}}", dms(12.56), 6, 0));
+  EXPECT_EQ("  13ms  ", fmt::format("{0:^{2}.{1}}", dms(12.56), 0, 8));
+  EXPECT_EQ("==13ms===", fmt::format("{:=^{}.{}}", dms(12.56), 9, 0));
+  EXPECT_EQ("***13ms***", fmt::format("{:*^10.0}", dms(12.56)));
 }
 
-TEST(ChronoTest, FormatSimpleQq) {
+TEST(chrono_test, format_simple_q) {
   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;
@@ -322,34 +492,42 @@ TEST(ChronoTest, FormatSimpleQq) {
   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");
+TEST(chrono_test, format_precision_q) {
+  EXPECT_THROW_MSG(
+      (void)fmt::format(runtime("{:.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) {
+TEST(chrono_test, format_full_specs_q) {
+  EXPECT_EQ("1 ms   ", fmt::format("{:7.0%Q %q}", dms(1.234)));
   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)));
+
+  EXPECT_EQ("13 ms  ", fmt::format("{:7.0%Q %q}", dms(12.56)));
+  EXPECT_EQ("   13 ms", fmt::format("{:>8.{}%Q %q}", dms(12.56), 0));
+  EXPECT_EQ(" 13 ms  ", fmt::format("{:^{}.{}%Q %q}", dms(12.56), 8, 0));
+  EXPECT_EQ("  13 ms  ", fmt::format("{0:^{2}.{1}%Q %q}", dms(12.56), 0, 9));
+  EXPECT_EQ("==13 ms==", fmt::format("{:=^{}.{}%Q %q}", dms(12.56), 9, 0));
+  EXPECT_EQ("***13 ms***", fmt::format("{:*^11.0%Q %q}", dms(12.56)));
 }
 
-TEST(ChronoTest, InvalidWidthId) {
-  EXPECT_THROW(fmt::format("{:{o}", std::chrono::seconds(0)),
+TEST(chrono_test, invalid_width_id) {
+  EXPECT_THROW((void)fmt::format(runtime("{:{o}"), std::chrono::seconds(0)),
                fmt::format_error);
 }
 
-TEST(ChronoTest, InvalidColons) {
-  EXPECT_THROW(fmt::format("{0}=:{0::", std::chrono::seconds(0)),
+TEST(chrono_test, invalid_colons) {
+  EXPECT_THROW((void)fmt::format(runtime("{0}=:{0::"), std::chrono::seconds(0)),
                fmt::format_error);
 }
 
-TEST(ChronoTest, NegativeDurations) {
+TEST(chrono_test, negative_durations) {
   EXPECT_EQ("-12345", fmt::format("{:%Q}", std::chrono::seconds(-12345)));
   EXPECT_EQ("-03:25:45",
             fmt::format("{:%H:%M:%S}", std::chrono::seconds(-12345)));
@@ -364,16 +542,13 @@ TEST(ChronoTest, NegativeDurations) {
             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));
+TEST(chrono_test, special_durations) {
+  auto value = fmt::format("{:%S}", std::chrono::duration<double>(1e20));
+  EXPECT_EQ(value, "40");
   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)),
@@ -384,4 +559,67 @@ TEST(ChronoTest, SpecialDurations) {
             "03:33:20");
 }
 
+TEST(chrono_test, unsigned_duration) {
+  EXPECT_EQ("42s", fmt::format("{}", std::chrono::duration<unsigned>(42)));
+}
+
+TEST(chrono_test, weekday) {
+  auto loc = get_locale("ru_RU.UTF-8");
+  std::locale::global(loc);
+  auto mon = fmt::weekday(1);
+
+  auto tm = std::tm();
+  tm.tm_wday = static_cast<int>(mon.c_encoding());
+
+  EXPECT_EQ(fmt::format("{}", mon), "Mon");
+  EXPECT_EQ(fmt::format("{:%a}", tm), "Mon");
+
+  if (loc != std::locale::classic()) {
+    EXPECT_THAT((std::vector<std::string>{"пн", "Пн", "пнд", "Пнд"}),
+                Contains(fmt::format(loc, "{:L}", mon)));
+    EXPECT_THAT((std::vector<std::string>{"пн", "Пн", "пнд", "Пнд"}),
+                Contains(fmt::format(loc, "{:%a}", tm)));
+  }
+}
+
+TEST(chrono_test, cpp20_duration_subsecond_support) {
+  using attoseconds = std::chrono::duration<long long, std::atto>;
+  // Check that 18 digits of subsecond precision are supported.
+  EXPECT_EQ(fmt::format("{:%S}", attoseconds{999999999999999999}),
+            "00.999999999999999999");
+  EXPECT_EQ(fmt::format("{:%S}", attoseconds{673231113420148734}),
+            "00.673231113420148734");
+  EXPECT_EQ(fmt::format("{:%S}", attoseconds{-673231113420148734}),
+            "-00.673231113420148734");
+  EXPECT_EQ(fmt::format("{:%S}", std::chrono::nanoseconds{13420148734}),
+            "13.420148734");
+  EXPECT_EQ(fmt::format("{:%S}", std::chrono::nanoseconds{-13420148734}),
+            "-13.420148734");
+  EXPECT_EQ(fmt::format("{:%S}", std::chrono::milliseconds{1234}), "01.234");
+  {
+    // Check that {:%H:%M:%S} is equivalent to {:%T}.
+    auto dur = std::chrono::milliseconds{3601234};
+    auto formatted_dur = fmt::format("{:%T}", dur);
+    EXPECT_EQ(formatted_dur, "01:00:01.234");
+    EXPECT_EQ(fmt::format("{:%H:%M:%S}", dur), formatted_dur);
+  }
+  using nanoseconds_dbl = std::chrono::duration<double, std::nano>;
+  EXPECT_EQ(fmt::format("{:%S}", nanoseconds_dbl{-123456789}), "-00.123456789");
+  EXPECT_EQ(fmt::format("{:%S}", nanoseconds_dbl{9123456789}), "09.123456789");
+  // Verify that only the seconds part is extracted and printed.
+  EXPECT_EQ(fmt::format("{:%S}", nanoseconds_dbl{99123456789}), "39.123456789");
+  EXPECT_EQ(fmt::format("{:%S}", nanoseconds_dbl{99123000000}), "39.123000000");
+  {
+    // Now the hour is printed, and we also test if negative doubles work.
+    auto dur = nanoseconds_dbl{-99123456789};
+    auto formatted_dur = fmt::format("{:%T}", dur);
+    EXPECT_EQ(formatted_dur, "-00:01:39.123456789");
+    EXPECT_EQ(fmt::format("{:%H:%M:%S}", dur), formatted_dur);
+  }
+  // Check that durations with precision greater than std::chrono::seconds have
+  // fixed precision, and print zeros even if there is no fractional part.
+  EXPECT_EQ(fmt::format("{:%S}", std::chrono::microseconds{7000000}),
+            "07.000000");
+}
+
 #endif  // FMT_STATIC_THOUSANDS_SEPARATOR

test/color-test.cc

@@ -7,62 +7,29 @@
 
 #include "fmt/color.h"
 
-#include "gtest-extra.h"
+#include <iterator>  // std::back_inserter
 
-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");
-}
+#include "gtest-extra.h"  // EXPECT_WRITE
 
-TEST(ColorsTest, Format) {
+TEST(color_test, format) {
   EXPECT_EQ(fmt::format(fg(fmt::rgb(255, 20, 30)), "rgb(255,20,30)"),
             "\x1b[38;2;255;020;030mrgb(255,20,30)\x1b[0m");
-  EXPECT_EQ(fmt::format(fg(fmt::rgb(255, 20, 30)), L"rgb(255,20,30) wide"),
-            L"\x1b[38;2;255;020;030mrgb(255,20,30) wide\x1b[0m");
   EXPECT_EQ(fmt::format(fg(fmt::color::blue), "blue"),
             "\x1b[38;2;000;000;255mblue\x1b[0m");
   EXPECT_EQ(
       fmt::format(fg(fmt::color::blue) | bg(fmt::color::red), "two color"),
       "\x1b[38;2;000;000;255m\x1b[48;2;255;000;000mtwo color\x1b[0m");
   EXPECT_EQ(fmt::format(fmt::emphasis::bold, "bold"), "\x1b[1mbold\x1b[0m");
+  EXPECT_EQ(fmt::format(fmt::emphasis::faint, "faint"), "\x1b[2mfaint\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::blink, "blink"), "\x1b[5mblink\x1b[0m");
+  EXPECT_EQ(fmt::format(fmt::emphasis::reverse, "reverse"),
+            "\x1b[7mreverse\x1b[0m");
+  EXPECT_EQ(fmt::format(fmt::emphasis::conceal, "conceal"),
+            "\x1b[8mconceal\x1b[0m");
   EXPECT_EQ(fmt::format(fmt::emphasis::strikethrough, "strikethrough"),
             "\x1b[9mstrikethrough\x1b[0m");
   EXPECT_EQ(
@@ -84,3 +51,16 @@ TEST(ColorsTest, Format) {
   EXPECT_EQ(fmt::format(fg(fmt::terminal_color::red), "{}", "foo"),
             "\x1b[31mfoo\x1b[0m");
 }
+
+TEST(color_test, format_to) {
+  auto out = std::string();
+  fmt::format_to(std::back_inserter(out), fg(fmt::rgb(255, 20, 30)),
+                 "rgb(255,20,30){}{}{}", 1, 2, 3);
+  EXPECT_EQ(fmt::to_string(out),
+            "\x1b[38;2;255;020;030mrgb(255,20,30)123\x1b[0m");
+}
+
+TEST(color_test, print) {
+  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");
+}

test/compile-error-test/CMakeLists.txt

@@ -1,71 +1,158 @@
 # Test if compile errors are produced where necessary.
 
-cmake_minimum_required(VERSION 3.1.0)
+cmake_minimum_required(VERSION 3.1...3.18)
+project(compile-error-test CXX)
 
-include(CheckCXXSourceCompiles)
-include(CheckCXXCompilerFlag)
+set(fmt_headers "
+  #include <fmt/format.h>
+  #include <fmt/xchar.h>
+")
 
-set(CMAKE_REQUIRED_INCLUDES ${CMAKE_CURRENT_SOURCE_DIR}/../../include)
-set(CMAKE_REQUIRED_FLAGS ${CXX_STANDARD_FLAG} ${PEDANTIC_COMPILE_FLAGS})
+set(error_test_names "")
+set(non_error_test_content "")
 
-function (generate_source result fragment)
-  set(${result} "
-  #define FMT_HEADER_ONLY 1
-  #include \"fmt/format.h\"
-  int main() {
-    ${fragment}
-  }
-  " PARENT_SCOPE)
+# For error tests (we expect them to produce compilation error):
+#  * adds a name of test into `error_test_names` list
+#  * generates a single source file (with the same name) for each test
+# For non-error tests (we expect them to compile successfully):
+#  * adds a code segment as separate function to `non_error_test_content`
+function (expect_compile name code_fragment)
+  cmake_parse_arguments(EXPECT_COMPILE "ERROR" "" "" ${ARGN})
+  string(MAKE_C_IDENTIFIER "${name}" test_name)
+
+  if (EXPECT_COMPILE_ERROR)
+    file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/test/${test_name}.cc" "
+      ${fmt_headers}
+      void ${test_name}() {
+        ${code_fragment}
+      }
+    ")
+    set(error_test_names_copy "${error_test_names}")
+    list(APPEND error_test_names_copy "${test_name}")
+    set(error_test_names "${error_test_names_copy}" PARENT_SCOPE)
+  else()
+    set(non_error_test_content "
+      ${non_error_test_content}
+      void ${test_name}() {
+        ${code_fragment}
+      }" PARENT_SCOPE)
+  endif()
 endfunction ()
 
-function (expect_compile code)
-  generate_source(source "${code}")
-  check_cxx_source_compiles("${source}" compiles)
-  if (NOT compiles)
-    set(error_msg "Compile error for: ${code}")
-  endif ()
-  # Unset the CMake cache variable compiles. Otherwise the compile test will
-  # just use cached information next time it runs.
-  unset(compiles CACHE)
-  if (error_msg)
-    message(FATAL_ERROR ${error_msg})
+# Generates a source file for non-error test with `non_error_test_content` and
+# CMake project file with all error and single non-error test targets.
+function (run_tests)
+  set(cmake_targets "")
+  foreach(test_name IN LISTS error_test_names)
+    set(cmake_targets "
+      ${cmake_targets}
+      add_library(test-${test_name} ${test_name}.cc)
+      target_link_libraries(test-${test_name} PRIVATE fmt::fmt)
+    ")
+  endforeach()
+
+  file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/test/non_error_test.cc" "
+    ${fmt_headers}
+    ${non_error_test_content}
+  ")
+  set(cmake_targets "
+    ${cmake_targets}
+    add_library(non-error-test non_error_test.cc)
+    target_link_libraries(non-error-test PRIVATE fmt::fmt)
+  ")
+
+  file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/test/CMakeLists.txt" "
+    cmake_minimum_required(VERSION 3.1...3.18)
+    project(tests CXX)
+    add_subdirectory(${FMT_DIR} fmt)
+    ${cmake_targets}
+  ")
+
+  set(build_directory "${CMAKE_CURRENT_BINARY_DIR}/test/build")
+  file(MAKE_DIRECTORY "${build_directory}")
+  execute_process(
+    COMMAND
+      "${CMAKE_COMMAND}"
+      "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
+      "-DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}"
+      "-DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}"
+      "-DCMAKE_GENERATOR=${CMAKE_GENERATOR}"
+      "-DCMAKE_MAKE_PROGRAM=${CMAKE_MAKE_PROGRAM}"
+      "-DFMT_DIR=${FMT_DIR}"
+      "${CMAKE_CURRENT_BINARY_DIR}/test"
+    WORKING_DIRECTORY "${build_directory}"
+    RESULT_VARIABLE result_var
+    OUTPUT_VARIABLE output_var
+    ERROR_VARIABLE output_var)
+  if (NOT result_var EQUAL 0)
+    message(FATAL_ERROR "Unable to configure:\n${output_var}")
+  endif()
+
+  foreach(test_name IN LISTS error_test_names)
+    execute_process(
+      COMMAND
+        "${CMAKE_COMMAND}" --build "${build_directory}" --target "test-${test_name}"
+      WORKING_DIRECTORY "${build_directory}"
+      RESULT_VARIABLE result_var
+      OUTPUT_VARIABLE output_var
+      ERROR_QUIET)
+    if (result_var EQUAL 0)
+      message(SEND_ERROR "No compile error for \"${test_name}\":\n${output_var}")
+    endif ()
+  endforeach()
+
+  execute_process(
+    COMMAND
+      "${CMAKE_COMMAND}" --build "${build_directory}" --target "non-error-test"
+    WORKING_DIRECTORY "${build_directory}"
+    RESULT_VARIABLE result_var
+    OUTPUT_VARIABLE output_var
+    ERROR_VARIABLE output_var)
+  if (NOT result_var EQUAL 0)
+    message(SEND_ERROR "Compile error for combined non-error test:\n${output_var}")
   endif ()
 endfunction ()
 
-function (expect_compile_error code)
-  generate_source(source "${code}")
-  check_cxx_source_compiles("${source}" compiles)
-  if (compiles)
-    set(error_msg "No compile error for: ${code}")
-  endif ()
-  # Unset the CMake cache variable compiles. Otherwise the compile test will
-  # just use cached information next time it runs.
-  unset(compiles CACHE)
-  if (error_msg)
-    message(FATAL_ERROR ${error_msg})
-  endif ()
-endfunction ()
 
 # check if the source file skeleton compiles
-expect_compile("")
+expect_compile(check "")
+expect_compile(check-error "compilation_error" ERROR)
 
 # Formatting a wide character with a narrow format string is forbidden.
-expect_compile_error("fmt::format(\"{}\", L'a');")
+expect_compile(wide-character-narrow-format-string "fmt::format(L\"{}\", L'a');")
+expect_compile(wide-character-narrow-format-string-error "fmt::format(\"{}\", L'a');" ERROR)
 
 # Formatting a wide string with a narrow format string is forbidden.
-expect_compile_error("fmt::format(\"{}\", L\"foo\");")
+expect_compile(wide-string-narrow-format-string "fmt::format(L\"{}\", L\"foo\");")
+expect_compile(wide-string-narrow-format-string-error "fmt::format(\"{}\", L\"foo\");" ERROR)
 
 # Formatting a narrow string with a wide format string is forbidden because
 # mixing UTF-8 with UTF-16/32 can result in an invalid output.
-expect_compile_error("fmt::format(L\"{}\", \"foo\");")
+expect_compile(narrow-string-wide-format-string "fmt::format(L\"{}\", L\"foo\");")
+expect_compile(narrow-string-wide-format-string-error "fmt::format(L\"{}\", \"foo\");" ERROR)
 
-# Formatting a wide string with a narrow format string is forbidden.
-expect_compile_error("
+expect_compile(cast-to-string "
+  struct S {
+    operator std::string() const { return std::string(); }
+  };
+  fmt::format(\"{}\", std::string(S()));
+")
+expect_compile(cast-to-string-error "
   struct S {
     operator std::string() const { return std::string(); }
   };
   fmt::format(\"{}\", S());
+" ERROR)
+
+# Formatting a function
+expect_compile(format-function "
+  void (*f)();
+  fmt::format(\"{}\", fmt::ptr(f));
 ")
+expect_compile(format-function-error "
+  void (*f)();
+  fmt::format(\"{}\", f);
+" ERROR)
 
 # Make sure that compiler features detected in the header
 # match the features detected in CMake.
@@ -74,6 +161,43 @@ if (SUPPORTS_USER_DEFINED_LITERALS)
 else ()
   set(supports_udl 0)
 endif ()
-expect_compile("#if FMT_USE_USER_DEFINED_LITERALS != ${supports_udl}
-                # error
-                #endif")
+expect_compile(udl-check "
+  #if FMT_USE_USER_DEFINED_LITERALS != ${supports_udl}
+  # error
+  #endif
+")
+
+if (CMAKE_CXX_STANDARD GREATER_EQUAL 20)
+  # Compile-time argument type check
+  expect_compile(format-string-number-spec "
+    #ifdef FMT_HAS_CONSTEVAL
+      fmt::format(\"{:d}\", 42);
+    #endif
+  ")
+  expect_compile(format-string-number-spec-error "
+    #ifdef FMT_HAS_CONSTEVAL
+      fmt::format(\"{:d}\", \"I am not a number\");
+    #else
+      #error
+    #endif
+  " ERROR)
+
+  # Compile-time argument name check
+  expect_compile(format-string-name "
+    #if defined(FMT_HAS_CONSTEVAL) && FMT_USE_NONTYPE_TEMPLATE_PARAMETERS
+      using namespace fmt::literals;
+      fmt::print(\"{foo}\", \"foo\"_a=42);
+    #endif
+  ")
+  expect_compile(format-string-name-error "
+    #if defined(FMT_HAS_CONSTEVAL) && FMT_USE_NONTYPE_TEMPLATE_PARAMETERS
+      using namespace fmt::literals;
+      fmt::print(\"{foo}\", \"bar\"_a=42);
+    #else
+      #error
+    #endif
+  " ERROR)
+endif ()
+
+# Run all tests
+run_tests()

test/compile-fp-test.cc

@@ -0,0 +1,62 @@
+// 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 "fmt/compile.h"
+#include "gmock/gmock.h"
+
+#if defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806 && \
+    defined(__cpp_constexpr) && __cpp_constexpr >= 201907 &&       \
+    defined(__cpp_constexpr_dynamic_alloc) &&                      \
+    __cpp_constexpr_dynamic_alloc >= 201907 && __cplusplus >= 202002L
+template <size_t max_string_length, typename Char = char> struct test_string {
+  template <typename T> constexpr bool operator==(const T& rhs) const noexcept {
+    return fmt::basic_string_view<Char>(rhs).compare(buffer) == 0;
+  }
+  Char buffer[max_string_length]{};
+};
+
+template <size_t max_string_length, typename Char = char, typename... Args>
+consteval auto test_format(auto format, const Args&... args) {
+  test_string<max_string_length, Char> string{};
+  fmt::format_to(string.buffer, format, args...);
+  return string;
+}
+
+TEST(compile_time_formatting_test, floating_point) {
+  EXPECT_EQ("0", test_format<2>(FMT_COMPILE("{}"), 0.0f));
+  EXPECT_EQ("392.500000", test_format<11>(FMT_COMPILE("{0:f}"), 392.5f));
+
+  EXPECT_EQ("0", test_format<2>(FMT_COMPILE("{:}"), 0.0));
+  EXPECT_EQ("0.000000", test_format<9>(FMT_COMPILE("{:f}"), 0.0));
+  EXPECT_EQ("0", test_format<2>(FMT_COMPILE("{:g}"), 0.0));
+  EXPECT_EQ("392.65", test_format<7>(FMT_COMPILE("{:}"), 392.65));
+  EXPECT_EQ("392.65", test_format<7>(FMT_COMPILE("{:g}"), 392.65));
+  EXPECT_EQ("392.65", test_format<7>(FMT_COMPILE("{:G}"), 392.65));
+  EXPECT_EQ("4.9014e+06", test_format<11>(FMT_COMPILE("{:g}"), 4.9014e6));
+  EXPECT_EQ("-392.650000", test_format<12>(FMT_COMPILE("{:f}"), -392.65));
+  EXPECT_EQ("-392.650000", test_format<12>(FMT_COMPILE("{:F}"), -392.65));
+
+  EXPECT_EQ("3.926500e+02", test_format<13>(FMT_COMPILE("{0:e}"), 392.65));
+  EXPECT_EQ("3.926500E+02", test_format<13>(FMT_COMPILE("{0:E}"), 392.65));
+  EXPECT_EQ("+0000392.6", test_format<11>(FMT_COMPILE("{0:+010.4g}"), 392.65));
+  EXPECT_EQ("9223372036854775808.000000",
+            test_format<27>(FMT_COMPILE("{:f}"), 9223372036854775807.0));
+
+  constexpr double nan = std::numeric_limits<double>::quiet_NaN();
+  EXPECT_EQ("nan", test_format<4>(FMT_COMPILE("{}"), nan));
+  EXPECT_EQ("+nan", test_format<5>(FMT_COMPILE("{:+}"), nan));
+  if (std::signbit(-nan))
+    EXPECT_EQ("-nan", test_format<5>(FMT_COMPILE("{}"), -nan));
+  else
+    fmt::print("Warning: compiler doesn't handle negative NaN correctly");
+
+  constexpr double inf = std::numeric_limits<double>::infinity();
+  EXPECT_EQ("inf", test_format<4>(FMT_COMPILE("{}"), inf));
+  EXPECT_EQ("+inf", test_format<5>(FMT_COMPILE("{:+}"), inf));
+  EXPECT_EQ("-inf", test_format<5>(FMT_COMPILE("{}"), -inf));
+}
+#endif

test/compile-test.cc

@@ -5,138 +5,100 @@
 //
 // 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 <type_traits>
+
+#include "fmt/chrono.h"
+#include "gmock/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::detail::compiled_format_base<decltype(format)> provider;
-  typedef fmt::detail::format_part<char>
-      expected_parts_type[EXPECTED_PARTS_COUNT];
-  static_assert(std::is_same<typename provider::parts_container,
-                             expected_parts_type>::value,
-                "CompileTimePreparedPartsTypeProvider test failed");
+TEST(iterator_test, counting_iterator) {
+  auto it = fmt::detail::counting_iterator();
+  auto prev = it++;
+  EXPECT_EQ(prev.count(), 0);
+  EXPECT_EQ(it.count(), 1);
+  EXPECT_EQ((it + 41).count(), 42);
 }
 
-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("{:{}.{}} {:{}}"));
+TEST(iterator_test, truncating_iterator) {
+  char* p = nullptr;
+  auto it = fmt::detail::truncating_iterator<char*>(p, 3);
+  auto prev = it++;
+  EXPECT_EQ(prev.base(), p);
+  EXPECT_EQ(it.base(), p + 1);
+}
 
-  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'
+TEST(iterator_test, truncating_iterator_default_construct) {
+  auto it = fmt::detail::truncating_iterator<char*>();
+  EXPECT_EQ(nullptr, it.base());
+  EXPECT_EQ(std::size_t{0}, it.count());
+}
+
+#ifdef __cpp_lib_ranges
+TEST(iterator_test, truncating_iterator_is_output_iterator) {
+  static_assert(
+      std::output_iterator<fmt::detail::truncating_iterator<char*>, char>);
 }
 #endif
 
-TEST(CompileTest, PassStringLiteralFormat) {
-  const auto prepared = fmt::detail::compile<int>("test {}");
-  EXPECT_EQ("test 42", fmt::format(prepared, 42));
-  const auto wprepared = fmt::detail::compile<int>(L"test {}");
-  EXPECT_EQ(L"test 42", fmt::format(wprepared, 42));
+TEST(iterator_test, truncating_back_inserter) {
+  auto buffer = std::string();
+  auto bi = std::back_inserter(buffer);
+  auto it = fmt::detail::truncating_iterator<decltype(bi)>(bi, 2);
+  *it++ = '4';
+  *it++ = '2';
+  *it++ = '1';
+  EXPECT_EQ(buffer.size(), 2);
+  EXPECT_EQ(buffer, "42");
 }
 
-TEST(CompileTest, FormatToArrayOfChars) {
-  char buffer[32] = {0};
-  const auto prepared = fmt::detail::compile<int>("4{}");
-  fmt::format_to(fmt::detail::make_checked(buffer, 32), prepared, 2);
-  EXPECT_EQ(std::string("42"), buffer);
-  wchar_t wbuffer[32] = {0};
-  const auto wprepared = fmt::detail::compile<int>(L"4{}");
-  fmt::format_to(fmt::detail::make_checked(wbuffer, 32), wprepared, 2);
-  EXPECT_EQ(std::wstring(L"42"), wbuffer);
+TEST(compile_test, compile_fallback) {
+  // FMT_COMPILE should fallback on runtime formatting when `if constexpr` is
+  // not available.
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42));
 }
 
-TEST(CompileTest, FormatToIterator) {
-  std::string s(2, ' ');
-  const auto prepared = fmt::detail::compile<int>("4{}");
-  fmt::format_to(s.begin(), prepared, 2);
-  EXPECT_EQ("42", s);
-  std::wstring ws(2, L' ');
-  const auto wprepared = fmt::detail::compile<int>(L"4{}");
-  fmt::format_to(ws.begin(), wprepared, 2);
-  EXPECT_EQ(L"42", ws);
-}
-
-TEST(CompileTest, FormatToN) {
-  char buf[5];
-  auto f = fmt::detail::compile<int>("{:10}");
-  auto result = fmt::format_to_n(buf, 5, f, 42);
-  EXPECT_EQ(result.size, 10);
-  EXPECT_EQ(result.out, buf + 5);
-  EXPECT_EQ(fmt::string_view(buf, 5), "     ");
-}
-
-TEST(CompileTest, FormattedSize) {
-  auto f = fmt::detail::compile<int>("{:10}");
-  EXPECT_EQ(fmt::formatted_size(f, 42), 10);
-}
-
-TEST(CompileTest, MultipleTypes) {
-  auto f = fmt::detail::compile<int, int>("{} {}");
-  EXPECT_EQ(fmt::format(f, 42, 42), "42 42");
-}
-
-struct formattable {};
+struct type_with_get {
+  template <int> friend void get(type_with_get);
+};
 
 FMT_BEGIN_NAMESPACE
-template <> struct formatter<formattable> : formatter<const char*> {
+template <> struct formatter<type_with_get> : formatter<int> {
   template <typename FormatContext>
-  auto format(formattable, FormatContext& ctx) -> decltype(ctx.out()) {
-    return formatter<const char*>::format("foo", ctx);
+  auto format(type_with_get, FormatContext& ctx) -> decltype(ctx.out()) {
+    return formatter<int>::format(42, ctx);
   }
 };
 FMT_END_NAMESPACE
 
-TEST(CompileTest, FormatUserDefinedType) {
-  auto f = fmt::detail::compile<formattable>("{}");
-  EXPECT_EQ(fmt::format(f, formattable()), "foo");
+TEST(compile_test, compile_type_with_get) {
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), type_with_get()));
 }
 
-TEST(CompileTest, EmptyFormatString) {
-  auto f = fmt::detail::compile<>("");
-  EXPECT_EQ(fmt::format(f), "");
-}
+#if defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+struct test_formattable {};
 
-#ifdef __cpp_if_constexpr
-TEST(CompileTest, FormatDefault) {
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<test_formattable> : formatter<const char*> {
+  char word_spec = 'f';
+  constexpr auto parse(format_parse_context& ctx) {
+    auto it = ctx.begin(), end = ctx.end();
+    if (it == end || *it == '}') return it;
+    if (it != end && (*it == 'f' || *it == 'b')) word_spec = *it++;
+    if (it != end && *it != '}') throw format_error("invalid format");
+    return it;
+  }
+  template <typename FormatContext>
+  constexpr auto format(test_formattable, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<const char*>::format(word_spec == 'f' ? "foo" : "bar",
+                                          ctx);
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(compile_test, format_default) {
   EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42));
   EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42u));
   EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42ll));
@@ -146,21 +108,269 @@ TEST(CompileTest, FormatDefault) {
   EXPECT_EQ("4.2", fmt::format(FMT_COMPILE("{}"), 4.2));
   EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), "foo"));
   EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), std::string("foo")));
-  EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), formattable()));
+  EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), test_formattable()));
+  auto t = std::chrono::system_clock::now();
+  EXPECT_EQ(fmt::format("{}", t), fmt::format(FMT_COMPILE("{}"), t));
+#  ifdef __cpp_lib_byte
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), std::byte{42}));
+#  endif
 }
 
-TEST(CompileTest, FormatSpecs) {
+TEST(compile_test, format_wide_string) {
+  EXPECT_EQ(L"42", fmt::format(FMT_COMPILE(L"{}"), 42));
+}
+
+TEST(compile_test, format_specs) {
   EXPECT_EQ("42", fmt::format(FMT_COMPILE("{:x}"), 0x42));
+  EXPECT_EQ("1.2 ms ",
+            fmt::format(FMT_COMPILE("{:7.1%Q %q}"),
+                        std::chrono::duration<double, std::milli>(1.234)));
 }
 
-TEST(CompileTest, FormatTo) {
+TEST(compile_test, dynamic_format_specs) {
+  EXPECT_EQ("foo  ", fmt::format(FMT_COMPILE("{:{}}"), "foo", 5));
+  EXPECT_EQ("  3.14", fmt::format(FMT_COMPILE("{:{}.{}f}"), 3.141592, 6, 2));
+  EXPECT_EQ(
+      "=1.234ms=",
+      fmt::format(FMT_COMPILE("{:=^{}.{}}"),
+                  std::chrono::duration<double, std::milli>(1.234), 9, 3));
+}
+
+TEST(compile_test, manual_ordering) {
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{0}"), 42));
+  EXPECT_EQ(" -42", fmt::format(FMT_COMPILE("{0:4}"), -42));
+  EXPECT_EQ("41 43", fmt::format(FMT_COMPILE("{0} {1}"), 41, 43));
+  EXPECT_EQ("41 43", fmt::format(FMT_COMPILE("{1} {0}"), 43, 41));
+  EXPECT_EQ("41 43", fmt::format(FMT_COMPILE("{0} {2}"), 41, 42, 43));
+  EXPECT_EQ("  41   43", fmt::format(FMT_COMPILE("{1:{2}} {0:4}"), 43, 41, 4));
+  EXPECT_EQ("42 1.2 ms ",
+            fmt::format(FMT_COMPILE("{0} {1:7.1%Q %q}"), 42,
+                        std::chrono::duration<double, std::milli>(1.234)));
+  EXPECT_EQ(
+      "true 42 42 foo 0x1234 foo",
+      fmt::format(FMT_COMPILE("{0} {1} {2} {3} {4} {5}"), true, 42, 42.0f,
+                  "foo", reinterpret_cast<void*>(0x1234), test_formattable()));
+  EXPECT_EQ(L"42", fmt::format(FMT_COMPILE(L"{0}"), 42));
+}
+
+TEST(compile_test, named) {
+  auto runtime_named_field_compiled =
+      fmt::detail::compile<decltype(fmt::arg("arg", 42))>(FMT_COMPILE("{arg}"));
+  static_assert(std::is_same_v<decltype(runtime_named_field_compiled),
+                               fmt::detail::runtime_named_field<char>>);
+
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), fmt::arg("arg", 42)));
+  EXPECT_EQ("41 43", fmt::format(FMT_COMPILE("{} {}"), fmt::arg("arg", 41),
+                                 fmt::arg("arg", 43)));
+
+  EXPECT_EQ("foobar",
+            fmt::format(FMT_COMPILE("{a0}{a1}"), fmt::arg("a0", "foo"),
+                        fmt::arg("a1", "bar")));
+  EXPECT_EQ("foobar", fmt::format(FMT_COMPILE("{}{a1}"), fmt::arg("a0", "foo"),
+                                  fmt::arg("a1", "bar")));
+  EXPECT_EQ("foofoo", fmt::format(FMT_COMPILE("{a0}{}"), fmt::arg("a0", "foo"),
+                                  fmt::arg("a1", "bar")));
+  EXPECT_EQ("foobar", fmt::format(FMT_COMPILE("{0}{a1}"), fmt::arg("a0", "foo"),
+                                  fmt::arg("a1", "bar")));
+  EXPECT_EQ("foobar", fmt::format(FMT_COMPILE("{a0}{1}"), fmt::arg("a0", "foo"),
+                                  fmt::arg("a1", "bar")));
+
+  EXPECT_EQ("foobar",
+            fmt::format(FMT_COMPILE("{}{a1}"), "foo", fmt::arg("a1", "bar")));
+  EXPECT_EQ("foobar",
+            fmt::format(FMT_COMPILE("{a0}{a1}"), fmt::arg("a1", "bar"),
+                        fmt::arg("a2", "baz"), fmt::arg("a0", "foo")));
+  EXPECT_EQ(" bar foo ",
+            fmt::format(FMT_COMPILE(" {foo} {bar} "), fmt::arg("foo", "bar"),
+                        fmt::arg("bar", "foo")));
+
+  EXPECT_THROW(fmt::format(FMT_COMPILE("{invalid}"), fmt::arg("valid", 42)),
+               fmt::format_error);
+
+#  if FMT_USE_NONTYPE_TEMPLATE_PARAMETERS
+  using namespace fmt::literals;
+  auto statically_named_field_compiled =
+      fmt::detail::compile<decltype("arg"_a = 42)>(FMT_COMPILE("{arg}"));
+  static_assert(std::is_same_v<decltype(statically_named_field_compiled),
+                               fmt::detail::field<char, int, 0>>);
+
+  EXPECT_EQ("41 43",
+            fmt::format(FMT_COMPILE("{a0} {a1}"), "a0"_a = 41, "a1"_a = 43));
+  EXPECT_EQ("41 43",
+            fmt::format(FMT_COMPILE("{a1} {a0}"), "a0"_a = 43, "a1"_a = 41));
+#  endif
+}
+
+TEST(compile_test, format_to) {
   char buf[8];
   auto end = fmt::format_to(buf, FMT_COMPILE("{}"), 42);
   *end = '\0';
   EXPECT_STREQ("42", buf);
+  end = fmt::format_to(buf, FMT_COMPILE("{:x}"), 42);
+  *end = '\0';
+  EXPECT_STREQ("2a", buf);
 }
 
-TEST(CompileTest, TextAndArg) {
+TEST(compile_test, format_to_n) {
+  constexpr auto buffer_size = 8;
+  char buffer[buffer_size];
+  auto res = fmt::format_to_n(buffer, buffer_size, FMT_COMPILE("{}"), 42);
+  *res.out = '\0';
+  EXPECT_STREQ("42", buffer);
+  res = fmt::format_to_n(buffer, buffer_size, FMT_COMPILE("{:x}"), 42);
+  *res.out = '\0';
+  EXPECT_STREQ("2a", buffer);
+}
+
+TEST(compile_test, formatted_size) {
+  EXPECT_EQ(2, fmt::formatted_size(FMT_COMPILE("{0}"), 42));
+  EXPECT_EQ(5, fmt::formatted_size(FMT_COMPILE("{0:<4.2f}"), 42.0));
+}
+
+TEST(compile_test, text_and_arg) {
   EXPECT_EQ(">>>42<<<", fmt::format(FMT_COMPILE(">>>{}<<<"), 42));
+  EXPECT_EQ("42!", fmt::format(FMT_COMPILE("{}!"), 42));
+}
+
+TEST(compile_test, unknown_format_fallback) {
+  EXPECT_EQ(" 42 ",
+            fmt::format(FMT_COMPILE("{name:^4}"), fmt::arg("name", 42)));
+
+  std::vector<char> v;
+  fmt::format_to(std::back_inserter(v), FMT_COMPILE("{name:^4}"),
+                 fmt::arg("name", 42));
+  EXPECT_EQ(" 42 ", fmt::string_view(v.data(), v.size()));
+
+  char buffer[4];
+  auto result = fmt::format_to_n(buffer, 4, FMT_COMPILE("{name:^5}"),
+                                 fmt::arg("name", 42));
+  EXPECT_EQ(5u, result.size);
+  EXPECT_EQ(buffer + 4, result.out);
+  EXPECT_EQ(" 42 ", fmt::string_view(buffer, 4));
+}
+
+TEST(compile_test, empty) { EXPECT_EQ("", fmt::format(FMT_COMPILE(""))); }
+
+struct to_stringable {
+  friend fmt::string_view to_string_view(to_stringable) { return {}; }
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<to_stringable> {
+  auto parse(format_parse_context& ctx) const -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const to_stringable&, FormatContext& ctx) -> decltype(ctx.out()) {
+    return ctx.out();
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(compile_test, to_string_and_formatter) {
+  fmt::format(FMT_COMPILE("{}"), to_stringable());
+}
+
+TEST(compile_test, print) {
+  EXPECT_WRITE(stdout, fmt::print(FMT_COMPILE("Don't {}!"), "panic"),
+               "Don't panic!");
+  EXPECT_WRITE(stderr, fmt::print(stderr, FMT_COMPILE("Don't {}!"), "panic"),
+               "Don't panic!");
+}
+#endif
+
+#if FMT_USE_NONTYPE_TEMPLATE_PARAMETERS
+TEST(compile_test, compile_format_string_literal) {
+  using namespace fmt::literals;
+  EXPECT_EQ("", fmt::format(""_cf));
+  EXPECT_EQ("42", fmt::format("{}"_cf, 42));
+  EXPECT_EQ(L"42", fmt::format(L"{}"_cf, 42));
+}
+#endif
+
+#if __cplusplus >= 202002L || \
+    (__cplusplus >= 201709L && FMT_GCC_VERSION >= 1002)
+template <size_t max_string_length, typename Char = char> struct test_string {
+  template <typename T> constexpr bool operator==(const T& rhs) const noexcept {
+    return fmt::basic_string_view<Char>(rhs).compare(buffer) == 0;
+  }
+  Char buffer[max_string_length]{};
+};
+
+template <size_t max_string_length, typename Char = char, typename... Args>
+consteval auto test_format(auto format, const Args&... args) {
+  test_string<max_string_length, Char> string{};
+  fmt::format_to(string.buffer, format, args...);
+  return string;
+}
+
+TEST(compile_time_formatting_test, bool) {
+  EXPECT_EQ("true", test_format<5>(FMT_COMPILE("{}"), true));
+  EXPECT_EQ("false", test_format<6>(FMT_COMPILE("{}"), false));
+  EXPECT_EQ("true ", test_format<6>(FMT_COMPILE("{:5}"), true));
+  EXPECT_EQ("1", test_format<2>(FMT_COMPILE("{:d}"), true));
+}
+
+TEST(compile_time_formatting_test, integer) {
+  EXPECT_EQ("42", test_format<3>(FMT_COMPILE("{}"), 42));
+  EXPECT_EQ("420", test_format<4>(FMT_COMPILE("{}"), 420));
+  EXPECT_EQ("42 42", test_format<6>(FMT_COMPILE("{} {}"), 42, 42));
+  EXPECT_EQ("42 42",
+            test_format<6>(FMT_COMPILE("{} {}"), uint32_t{42}, uint64_t{42}));
+
+  EXPECT_EQ("+42", test_format<4>(FMT_COMPILE("{:+}"), 42));
+  EXPECT_EQ("42", test_format<3>(FMT_COMPILE("{:-}"), 42));
+  EXPECT_EQ(" 42", test_format<4>(FMT_COMPILE("{: }"), 42));
+
+  EXPECT_EQ("-0042", test_format<6>(FMT_COMPILE("{:05}"), -42));
+
+  EXPECT_EQ("101010", test_format<7>(FMT_COMPILE("{:b}"), 42));
+  EXPECT_EQ("0b101010", test_format<9>(FMT_COMPILE("{:#b}"), 42));
+  EXPECT_EQ("0B101010", test_format<9>(FMT_COMPILE("{:#B}"), 42));
+  EXPECT_EQ("042", test_format<4>(FMT_COMPILE("{:#o}"), 042));
+  EXPECT_EQ("0x4a", test_format<5>(FMT_COMPILE("{:#x}"), 0x4a));
+  EXPECT_EQ("0X4A", test_format<5>(FMT_COMPILE("{:#X}"), 0x4a));
+
+  EXPECT_EQ("   42", test_format<6>(FMT_COMPILE("{:5}"), 42));
+  EXPECT_EQ("   42", test_format<6>(FMT_COMPILE("{:5}"), 42ll));
+  EXPECT_EQ("   42", test_format<6>(FMT_COMPILE("{:5}"), 42ull));
+
+  EXPECT_EQ("42  ", test_format<5>(FMT_COMPILE("{:<4}"), 42));
+  EXPECT_EQ("  42", test_format<5>(FMT_COMPILE("{:>4}"), 42));
+  EXPECT_EQ(" 42 ", test_format<5>(FMT_COMPILE("{:^4}"), 42));
+  EXPECT_EQ("**-42", test_format<6>(FMT_COMPILE("{:*>5}"), -42));
+}
+
+TEST(compile_time_formatting_test, char) {
+  EXPECT_EQ("c", test_format<2>(FMT_COMPILE("{}"), 'c'));
+
+  EXPECT_EQ("c  ", test_format<4>(FMT_COMPILE("{:3}"), 'c'));
+  EXPECT_EQ("99", test_format<3>(FMT_COMPILE("{:d}"), 'c'));
+}
+
+TEST(compile_time_formatting_test, string) {
+  EXPECT_EQ("42", test_format<3>(FMT_COMPILE("{}"), "42"));
+  EXPECT_EQ("The answer is 42",
+            test_format<17>(FMT_COMPILE("{} is {}"), "The answer", "42"));
+
+  EXPECT_EQ("abc**", test_format<6>(FMT_COMPILE("{:*<5}"), "abc"));
+  EXPECT_EQ("**🤡**", test_format<9>(FMT_COMPILE("{:*^6}"), "🤡"));
+}
+
+TEST(compile_time_formatting_test, combination) {
+  EXPECT_EQ("420, true, answer",
+            test_format<18>(FMT_COMPILE("{}, {}, {}"), 420, true, "answer"));
+
+  EXPECT_EQ(" -42", test_format<5>(FMT_COMPILE("{:{}}"), -42, 4));
+}
+
+TEST(compile_time_formatting_test, custom_type) {
+  EXPECT_EQ("foo", test_format<4>(FMT_COMPILE("{}"), test_formattable()));
+  EXPECT_EQ("bar", test_format<4>(FMT_COMPILE("{:b}"), test_formattable()));
+}
+
+TEST(compile_time_formatting_test, multibyte_fill) {
+  EXPECT_EQ("жж42", test_format<8>(FMT_COMPILE("{:ж>4}"), 42));
 }
 #endif

test/custom-formatter-test.cc

@@ -1,58 +0,0 @@
-// Formatting library for C++ - custom argument formatter tests
-//
-// Copyright (c) 2012 - present, Victor Zverovich
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-#ifndef _CRT_SECURE_NO_WARNINGS
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-
-#include "fmt/format.h"
-#include "gtest-extra.h"
-
-// MSVC 2013 is known to be broken.
-#if !FMT_MSC_VER || FMT_MSC_VER > 1800
-
-// A custom argument formatter that doesn't print `-` for floating-point values
-// rounded to 0.
-class custom_arg_formatter
-    : public fmt::detail::arg_formatter<fmt::format_context::iterator, char> {
- public:
-  using base = fmt::detail::arg_formatter<fmt::format_context::iterator, char>;
-
-  custom_arg_formatter(fmt::format_context& ctx,
-                       fmt::format_parse_context* parse_ctx,
-                       fmt::format_specs* s = nullptr,
-                       const char* = 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, specs()->precision)) == 0.0) value = 0;
-    return base::operator()(value);
-  }
-};
-
-std::string custom_vformat(fmt::string_view format_str, fmt::format_args args) {
-  fmt::memory_buffer buffer;
-  fmt::detail::buffer<char>& base = buffer;
-  // Pass custom argument formatter as a template arg to vwrite.
-  fmt::vformat_to<custom_arg_formatter>(std::back_inserter(base), format_str,
-                                        args);
-  return std::string(buffer.data(), buffer.size());
-}
-
-template <typename... Args>
-std::string custom_format(const char* format_str, const Args&... args) {
-  auto va = fmt::make_format_args(args...);
-  return custom_vformat(format_str, va);
-}
-
-TEST(CustomFormatterTest, Format) {
-  EXPECT_EQ("0.00", custom_format("{:.2f}", -.00001));
-}
-#endif

test/enforce-checks-test.cc

@@ -0,0 +1,63 @@
+// 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 <iterator>
+#include <vector>
+
+#include "fmt/chrono.h"
+#include "fmt/color.h"
+#include "fmt/format.h"
+#include "fmt/ostream.h"
+#include "fmt/ranges.h"
+#include "fmt/xchar.h"
+
+// Exercise the API to verify that everything we expect to can compile.
+void test_format_api() {
+  (void)fmt::format(FMT_STRING("{}"), 42);
+  (void)fmt::format(FMT_STRING(L"{}"), 42);
+  (void)fmt::format(FMT_STRING("noop"));
+
+  (void)fmt::to_string(42);
+  (void)fmt::to_wstring(42);
+
+  std::vector<char> out;
+  fmt::format_to(std::back_inserter(out), FMT_STRING("{}"), 42);
+
+  char buffer[4];
+  fmt::format_to_n(buffer, 3, FMT_STRING("{}"), 12345);
+
+  wchar_t wbuffer[4];
+  fmt::format_to_n(wbuffer, 3, FMT_STRING(L"{}"), 12345);
+}
+
+void test_chrono() {
+  (void)fmt::format(FMT_STRING("{}"), std::chrono::seconds(42));
+  (void)fmt::format(FMT_STRING(L"{}"), std::chrono::seconds(42));
+}
+
+void test_text_style() {
+  fmt::print(fg(fmt::rgb(255, 20, 30)), FMT_STRING("{}"), "rgb(255,20,30)");
+  (void)fmt::format(fg(fmt::rgb(255, 20, 30)), FMT_STRING("{}"),
+                    "rgb(255,20,30)");
+
+  fmt::text_style ts = fg(fmt::rgb(255, 20, 30));
+  std::string out;
+  fmt::format_to(std::back_inserter(out), ts,
+                 FMT_STRING("rgb(255,20,30){}{}{}"), 1, 2, 3);
+}
+
+void test_range() {
+  std::vector<char> hello = {'h', 'e', 'l', 'l', 'o'};
+  (void)fmt::format(FMT_STRING("{}"), hello);
+}
+
+int main() {
+  test_format_api();
+  test_chrono();
+  test_text_style();
+  test_range();
+}

test/find-package-test/CMakeLists.txt

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

test/find-package-test/main.cc

@@ -1,6 +1,5 @@
 #include "fmt/format.h"
 
 int main(int argc, char** argv) {
-  for(int i = 0; i < argc; ++i)
-    fmt::print("{}: {}\n", i, argv[i]);
+  for (int i = 0; i < argc; ++i) fmt::print("{}: {}\n", i, argv[i]);
 }

test/format

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

test/format-dyn-args-test.cc

@@ -1,6 +0,0 @@
-// Copyright (c) 2020 Vladimir Solontsov
-// SPDX-License-Identifier: MIT Licence
-
-#include <fmt/core.h>
-
-#include "gtest-extra.h"

test/format-impl-test.cc

@@ -5,21 +5,16 @@
 //
 // For the license information refer to format.h.
 
-#define FMT_NOEXCEPT
-#undef FMT_SHARED
-#include "test-assert.h"
-
-// Include format.cc instead of format.h to test implementation.
 #include <algorithm>
 #include <cstring>
 
-#include "../src/format.cc"
-#include "fmt/printf.h"
-#include "gmock.h"
-#include "gtest-extra.h"
-#include "util.h"
+// clang-format off
+#include "test-assert.h"
+// clang-format on
 
-#undef max
+#include "fmt/format.h"
+#include "gmock/gmock.h"
+#include "util.h"
 
 using fmt::detail::bigint;
 using fmt::detail::fp;
@@ -28,13 +23,13 @@ using fmt::detail::max_value;
 static_assert(!std::is_copy_constructible<bigint>::value, "");
 static_assert(!std::is_copy_assignable<bigint>::value, "");
 
-TEST(BigIntTest, Construct) {
+TEST(bigint_test, construct) {
   EXPECT_EQ("", fmt::format("{}", bigint()));
   EXPECT_EQ("42", fmt::format("{}", bigint(0x42)));
   EXPECT_EQ("123456789abcedf0", fmt::format("{}", bigint(0x123456789abcedf0)));
 }
 
-TEST(BigIntTest, Compare) {
+TEST(bigint_test, compare) {
   bigint n1(42);
   bigint n2(42);
   EXPECT_EQ(compare(n1, n2), 0);
@@ -48,7 +43,7 @@ TEST(BigIntTest, Compare) {
   EXPECT_GT(compare(n4, n2), 0);
 }
 
-TEST(BigIntTest, AddCompare) {
+TEST(bigint_test, add_compare) {
   EXPECT_LT(
       add_compare(bigint(0xffffffff), bigint(0xffffffff), bigint(1) <<= 64), 0);
   EXPECT_LT(add_compare(bigint(1) <<= 32, bigint(1), bigint(1) <<= 96), 0);
@@ -74,7 +69,7 @@ TEST(BigIntTest, AddCompare) {
             0);
 }
 
-TEST(BigIntTest, ShiftLeft) {
+TEST(bigint_test, shift_left) {
   bigint n(0x42);
   n <<= 0;
   EXPECT_EQ("42", fmt::format("{}", n));
@@ -84,7 +79,7 @@ TEST(BigIntTest, ShiftLeft) {
   EXPECT_EQ("108000000", fmt::format("{}", n));
 }
 
-TEST(BigIntTest, Multiply) {
+TEST(bigint_test, multiply) {
   bigint n(0x42);
   EXPECT_THROW(n *= 0, assertion_failure);
   n *= 1;
@@ -101,7 +96,7 @@ TEST(BigIntTest, Multiply) {
   EXPECT_EQ("fffffffffffffffe0000000000000001", fmt::format("{}", bigmax));
 }
 
-TEST(BigIntTest, Accumulator) {
+TEST(bigint_test, accumulator) {
   fmt::detail::accumulator acc;
   EXPECT_EQ(acc.lower, 0);
   EXPECT_EQ(acc.upper, 0);
@@ -110,7 +105,7 @@ TEST(BigIntTest, Accumulator) {
   EXPECT_EQ(static_cast<uint32_t>(acc), 34);
   acc += 56;
   EXPECT_EQ(acc.lower, 90);
-  acc += fmt::detail::max_value<uint64_t>();
+  acc += max_value<uint64_t>();
   EXPECT_EQ(acc.upper, 13);
   EXPECT_EQ(acc.lower, 89);
   acc >>= 32;
@@ -118,7 +113,7 @@ TEST(BigIntTest, Accumulator) {
   EXPECT_EQ(acc.lower, 13 * 0x100000000);
 }
 
-TEST(BigIntTest, Square) {
+TEST(bigint_test, square) {
   bigint n0(0);
   n0.square();
   EXPECT_EQ("0", fmt::format("{}", n0));
@@ -136,18 +131,18 @@ TEST(BigIntTest, Square) {
   EXPECT_EQ("2540be400", fmt::format("{}", n4));
 }
 
-TEST(BigIntTest, DivModAssignZeroDivisor) {
+TEST(bigint_test, divmod_assign_zero_divisor) {
   bigint zero(0);
   EXPECT_THROW(bigint(0).divmod_assign(zero), assertion_failure);
   EXPECT_THROW(bigint(42).divmod_assign(zero), assertion_failure);
 }
 
-TEST(BigIntTest, DivModAssignSelf) {
+TEST(bigint_test, divmod_assign_self) {
   bigint n(100);
   EXPECT_THROW(n.divmod_assign(n), assertion_failure);
 }
 
-TEST(BigIntTest, DivModAssignUnaligned) {
+TEST(bigint_test, divmod_assign_unaligned) {
   // (42 << 340) / pow(10, 100):
   bigint n1(42);
   n1 <<= 340;
@@ -159,7 +154,7 @@ TEST(BigIntTest, DivModAssignUnaligned) {
             fmt::format("{}", n1));
 }
 
-TEST(BigIntTest, DivModAssign) {
+TEST(bigint_test, divmod_assign) {
   // 100 / 10:
   bigint n1(100);
   int result = n1.divmod_assign(bigint(10));
@@ -186,70 +181,20 @@ template <bool is_iec559> void run_double_tests() {
 template <> void run_double_tests<true>() {
   // Construct from double.
   EXPECT_EQ(fp(1.23), fp(0x13ae147ae147aeu, -52));
-
-  // Compute boundaries:
-  fp value;
-  // Normalized & not power of 2 - equidistant boundaries:
-  auto b = value.assign_with_boundaries(1.23);
-  EXPECT_EQ(value, fp(0x0013ae147ae147ae, -52));
-  EXPECT_EQ(b.lower, 0x9d70a3d70a3d6c00);
-  EXPECT_EQ(b.upper, 0x9d70a3d70a3d7400);
-  // Normalized power of 2 - lower boundary is closer:
-  b = value.assign_with_boundaries(1.9807040628566084e+28);  // 2**94
-  EXPECT_EQ(value, fp(0x0010000000000000, 42));
-  EXPECT_EQ(b.lower, 0x7ffffffffffffe00);
-  EXPECT_EQ(b.upper, 0x8000000000000400);
-  // Smallest normalized double - equidistant boundaries:
-  b = value.assign_with_boundaries(2.2250738585072014e-308);
-  EXPECT_EQ(value, fp(0x0010000000000000, -1074));
-  EXPECT_EQ(b.lower, 0x7ffffffffffffc00);
-  EXPECT_EQ(b.upper, 0x8000000000000400);
-  // Subnormal - equidistant boundaries:
-  b = value.assign_with_boundaries(4.9406564584124654e-324);
-  EXPECT_EQ(value, fp(0x0000000000000001, -1074));
-  EXPECT_EQ(b.lower, 0x4000000000000000);
-  EXPECT_EQ(b.upper, 0xc000000000000000);
 }
 
-TEST(FPTest, DoubleTests) {
+TEST(fp_test, double_tests) {
   run_double_tests<std::numeric_limits<double>::is_iec559>();
 }
 
-TEST(FPTest, Normalize) {
+TEST(fp_test, normalize) {
   const auto v = fp(0xbeef, 42);
   auto normalized = normalize(v);
   EXPECT_EQ(0xbeef000000000000, normalized.f);
   EXPECT_EQ(-6, normalized.e);
 }
 
-TEST(FPTest, ComputeFloatBoundaries) {
-  struct {
-    double x, lower, upper;
-  } tests[] = {
-      // regular
-      {1.5f, 1.4999999403953552, 1.5000000596046448},
-      // boundary
-      {1.0f, 0.9999999701976776, 1.0000000596046448},
-      // min normal
-      {1.1754944e-38f, 1.1754942807573643e-38, 1.1754944208872107e-38},
-      // max subnormal
-      {1.1754942e-38f, 1.1754941406275179e-38, 1.1754942807573643e-38},
-      // min subnormal
-      {1e-45f, 7.006492321624085e-46, 2.1019476964872256e-45},
-  };
-  for (auto test : tests) {
-    fp vlower = normalize(fp(test.lower));
-    fp vupper = normalize(fp(test.upper));
-    vlower.f >>= vupper.e - vlower.e;
-    vlower.e = vupper.e;
-    fp value;
-    auto b = value.assign_float_with_boundaries(test.x);
-    EXPECT_EQ(vlower.f, b.lower);
-    EXPECT_EQ(vupper.f, b.upper);
-  }
-}
-
-TEST(FPTest, Multiply) {
+TEST(fp_test, multiply) {
   auto v = fp(123ULL << 32, 4) * fp(56ULL << 32, 7);
   EXPECT_EQ(v.f, 123u * 56u);
   EXPECT_EQ(v.e, 4 + 7 + 64);
@@ -258,19 +203,57 @@ TEST(FPTest, Multiply) {
   EXPECT_EQ(v.e, 4 + 8 + 64);
 }
 
-TEST(FPTest, GetCachedPower) {
-  typedef std::numeric_limits<double> limits;
+TEST(fp_test, get_cached_power) {
+  using limits = std::numeric_limits<double>;
   for (auto exp = limits::min_exponent; exp <= limits::max_exponent; ++exp) {
     int dec_exp = 0;
     auto fp = fmt::detail::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));
+    bigint exact, cache(fp.f);
+    if (dec_exp >= 0) {
+      exact.assign_pow10(dec_exp);
+      if (fp.e <= 0)
+        exact <<= -fp.e;
+      else
+        cache <<= fp.e;
+      exact.align(cache);
+      cache.align(exact);
+      auto exact_str = fmt::format("{}", exact);
+      auto cache_str = fmt::format("{}", cache);
+      EXPECT_EQ(exact_str.size(), cache_str.size());
+      EXPECT_EQ(exact_str.substr(0, 15), cache_str.substr(0, 15));
+      int diff = cache_str[15] - exact_str[15];
+      if (diff == 1)
+        EXPECT_GT(exact_str[16], '8');
+      else
+        EXPECT_EQ(diff, 0);
+    } else {
+      cache.assign_pow10(-dec_exp);
+      cache *= fp.f + 1;  // Inexact check.
+      exact.assign(1);
+      exact <<= -fp.e;
+      exact.align(cache);
+      auto exact_str = fmt::format("{}", exact);
+      auto cache_str = fmt::format("{}", cache);
+      EXPECT_EQ(exact_str.size(), cache_str.size());
+      EXPECT_EQ(exact_str.substr(0, 16), cache_str.substr(0, 16));
+    }
   }
 }
 
-TEST(FPTest, GetRoundDirection) {
+TEST(fp_test, dragonbox_max_k) {
+  using fmt::detail::dragonbox::floor_log10_pow2;
+  using float_info = fmt::detail::dragonbox::float_info<float>;
+  EXPECT_EQ(fmt::detail::const_check(float_info::max_k),
+            float_info::kappa - floor_log10_pow2(float_info::min_exponent -
+                                                 float_info::significand_bits));
+  using double_info = fmt::detail::dragonbox::float_info<double>;
+  EXPECT_EQ(
+      fmt::detail::const_check(double_info::max_k),
+      double_info::kappa - floor_log10_pow2(double_info::min_exponent -
+                                            double_info::significand_bits));
+}
+
+TEST(fp_test, get_round_direction) {
   using fmt::detail::get_round_direction;
   using fmt::detail::round_direction;
   EXPECT_EQ(round_direction::down, get_round_direction(100, 50, 0));
@@ -294,116 +277,42 @@ TEST(FPTest, GetRoundDirection) {
   EXPECT_EQ(round_direction::up, get_round_direction(max, max - 1, 1));
 }
 
-TEST(FPTest, FixedHandler) {
-  struct handler : fmt::detail::fixed_handler {
+TEST(fp_test, fixed_handler) {
+  struct handler : fmt::detail::gen_digits_handler {
     char buffer[10];
-    handler(int prec = 0) : fmt::detail::fixed_handler() {
+    handler(int prec = 0) : fmt::detail::gen_digits_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);
+  handler().on_digit('0', 100, 99, 0, false);
+  EXPECT_THROW(handler().on_digit('0', 100, 100, 0, false), assertion_failure);
   namespace digits = fmt::detail::digits;
-  EXPECT_EQ(handler(1).on_digit('0', 100, 10, 10, exp, false), digits::done);
+  EXPECT_EQ(handler(1).on_digit('0', 100, 10, 10, false), digits::error);
   // Check that divisor - error doesn't overflow.
-  EXPECT_EQ(handler(1).on_digit('0', 100, 10, 101, exp, false), digits::error);
+  EXPECT_EQ(handler(1).on_digit('0', 100, 10, 101, 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);
+  EXPECT_EQ(handler(1).on_digit('0', max, 10, max - 1, false), digits::error);
 }
 
-TEST(FPTest, GrisuFormatCompilesWithNonIEEEDouble) {
+TEST(fp_test, grisu_format_compiles_with_on_ieee_double) {
   fmt::memory_buffer buf;
   format_float(0.42, -1, fmt::detail::float_specs(), buf);
 }
 
-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()));
-  }
-
-#if FMT_USE_INT128
-  // Apple Clang does not define typeid for __int128_t and __uint128_t.
-  FMT_NORETURN T operator()(fmt::detail::int128_t) {
-    throw std::runtime_error("invalid type __int128_t");
-  }
-
-  FMT_NORETURN T operator()(fmt::detail::uint128_t) {
-    throw std::runtime_error("invalid type __uint128_t");
-  }
-#endif
-};
-
-TEST(FormatTest, ArgConverter) {
-  long long value = max_value<long long>();
-  auto arg = fmt::detail::make_arg<fmt::format_context>(value);
-  fmt::visit_format_arg(
-      fmt::detail::arg_converter<long long, fmt::format_context>(arg, 'd'),
-      arg);
-  EXPECT_EQ(value, fmt::visit_format_arg(value_extractor<long long>(), arg));
-}
-
-TEST(FormatTest, FormatNegativeNaN) {
-  double nan = std::numeric_limits<double>::quiet_NaN();
-  if (std::signbit(-nan))
-    EXPECT_EQ("-nan", fmt::format("{}", -nan));
-  else
-    fmt::print("Warning: compiler doesn't handle negative NaN correctly");
-}
-
-TEST(FormatTest, StrError) {
-  char* message = nullptr;
-  char buffer[BUFFER_SIZE];
-  EXPECT_ASSERT(fmt::detail::safe_strerror(EDOM, message = nullptr, 0),
-                "invalid buffer");
-  EXPECT_ASSERT(fmt::detail::safe_strerror(EDOM, message = buffer, 0),
-                "invalid buffer");
-  buffer[0] = 'x';
-#if defined(_GNU_SOURCE) && !defined(__COVERITY__)
-  // Use invalid error code to make sure that safe_strerror returns an error
-  // message in the buffer rather than a pointer to a static string.
-  int error_code = -1;
-#else
-  int error_code = EDOM;
-#endif
-
-  int result =
-      fmt::detail::safe_strerror(error_code, message = buffer, BUFFER_SIZE);
-  EXPECT_EQ(result, 0);
-  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.
-#if !defined(__MINGW32__) && !defined(__sun)
-  result =
-      fmt::detail::safe_strerror(error_code, message = buffer, message_size);
-  EXPECT_EQ(ERANGE, result);
-  result = fmt::detail::safe_strerror(error_code, message = buffer, 1);
-  EXPECT_EQ(buffer, message);  // Message should point to buffer.
-  EXPECT_EQ(ERANGE, result);
-  EXPECT_STREQ("", message);
-#endif
-}
-
-TEST(FormatTest, FormatErrorCode) {
+TEST(format_impl_test, format_error_code) {
   std::string msg = "error 42", sep = ": ";
   {
     fmt::memory_buffer buffer;
-    format_to(buffer, "garbage");
+    format_to(fmt::appender(buffer), "garbage");
     fmt::detail::format_error_code(buffer, 42, "test");
     EXPECT_EQ("test: " + msg, to_string(buffer));
   }
   {
     fmt::memory_buffer buffer;
-    std::string prefix(fmt::inline_buffer_size - msg.size() - sep.size() + 1,
-                       'x');
+    auto prefix =
+        std::string(fmt::inline_buffer_size - msg.size() - sep.size() + 1, 'x');
     fmt::detail::format_error_code(buffer, 42, prefix);
     EXPECT_EQ(msg, to_string(buffer));
   }
@@ -412,7 +321,8 @@ 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');
+    auto prefix =
+        std::string(fmt::inline_buffer_size - msg.size() - sep.size(), 'x');
     fmt::detail::format_error_code(buffer, codes[i], prefix);
     EXPECT_EQ(prefix + sep + msg, to_string(buffer));
     size_t size = fmt::inline_buffer_size;
@@ -425,9 +335,9 @@ TEST(FormatTest, FormatErrorCode) {
   }
 }
 
-TEST(FormatTest, CountCodePoints) {
+TEST(format_impl_test, compute_width) {
   EXPECT_EQ(4,
-            fmt::detail::count_code_points(
+            fmt::detail::compute_width(
                 fmt::basic_string_view<fmt::detail::char8_type>(
                     reinterpret_cast<const fmt::detail::char8_type*>("ёжик"))));
 }
@@ -442,15 +352,26 @@ template <typename Int> void test_count_digits() {
   }
 }
 
-TEST(UtilTest, CountDigits) {
+TEST(format_impl_test, count_digits) {
   test_count_digits<uint32_t>();
   test_count_digits<uint64_t>();
 }
 
-TEST(UtilTest, WriteFallbackUIntPtr) {
+TEST(format_impl_test, write_fallback_uintptr) {
   std::string s;
   fmt::detail::write_ptr<char>(
       std::back_inserter(s),
       fmt::detail::fallback_uintptr(reinterpret_cast<void*>(0xface)), nullptr);
   EXPECT_EQ(s, "0xface");
 }
+
+#ifdef _WIN32
+#  include <windows.h>
+#endif
+
+#ifdef _WIN32
+TEST(format_impl_test, write_console_signature) {
+  decltype(WriteConsoleW)* p = fmt::detail::WriteConsoleW;
+  (void)p;
+}
+#endif

test/fuzzing/CMakeLists.txt

@@ -1,38 +1,30 @@
 # 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)
+# Link in the main function. Useful for reproducing, kcov, gdb, afl, valgrind.
+# (Note that libFuzzer can also reproduce, just pass it the files.)
+option(FMT_FUZZ_LINKMAIN "Enables the reproduce mode, instead of libFuzzer" On)
 
 # For oss-fuzz - insert $LIB_FUZZING_ENGINE into the link flags, but only for
-# the fuzz targets, otherwise the cmake configuration step fails.
+# 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)
+# Adds a binary for reproducing, i.e. no fuzzing, just enables replaying data
+# through the fuzzers.
+function(add_fuzzer source)
+  get_filename_component(basename ${source} NAME_WE)
+  set(name ${basename}-fuzzer)
+  add_executable(${name} ${source} fuzzer-common.h)
   if (FMT_FUZZ_LINKMAIN)
-      target_sources(${name} PRIVATE main.cpp)
+    target_sources(${name} PRIVATE main.cc)
   endif ()
   target_link_libraries(${name} PRIVATE fmt)
-if (FMT_FUZZ_LDFLAGS)
-  target_link_libraries(${name} PRIVATE ${FMT_FUZZ_LDFLAGS})
-endif ()
+  if (FMT_FUZZ_LDFLAGS)
+    target_link_libraries(${name} PRIVATE ${FMT_FUZZ_LDFLAGS})
+  endif ()
   target_compile_features(${name} PRIVATE cxx_generic_lambdas)
-endmacro ()
+endfunction()
 
-foreach (X IN ITEMS ${SOURCES})
-  implement_fuzzer(${X})
+foreach (source chrono-duration.cc chrono-timepoint.cc float.cc named-arg.cc one-arg.cc two-args.cc)
+  add_fuzzer(${source})
 endforeach ()

test/fuzzing/README.md

@@ -1,27 +1,4 @@
-# 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 FMT_FUZZ
-if(spec.precision>100000) {
-  throw std::runtime_error("fuzz mode - avoiding large precision");
-}
-#endif
-``` 
-This macro `FMT_FUZZ` is enabled on OSS-Fuzz builds and makes fuzzing
-practically possible. It is used in fmt code to prevent resource exhaustion in
-fuzzing mode.  
-The macro `FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION` is the
-defacto standard for making fuzzing practically possible to disable certain
-fuzzing-unfriendly features (for example, randomness), see [the libFuzzer
-documentation](https://llvm.org/docs/LibFuzzer.html#fuzzer-friendly-build-mode).
-
-## Running the fuzzers locally
+# 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
@@ -34,7 +11,7 @@ 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 .. -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.
@@ -44,5 +21,5 @@ Execute a fuzzer with for instance
 cd build
 export UBSAN_OPTIONS=halt_on_error=1
 mkdir out_chrono
-bin/fuzzer_chrono_duration  out_chrono
+bin/fuzzer_chrono_duration out_chrono
 ```

test/fuzzing/build.sh

@@ -1,7 +1,6 @@
 #!/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)
@@ -9,7 +8,7 @@
 #
 # Copyright (c) 2019 Paul Dreik
 #
-# License: see LICENSE.rst in the fmt root directory
+# For the license information refer to format.h.
 
 set -e
 me=$(basename $0)
@@ -23,16 +22,9 @@ here=$(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
+CLANG=clang++-11
 
-#for performance analysis of the fuzzers
+# For performance analysis of the fuzzers.
 builddir=$here/build-fuzzers-perfanalysis
 mkdir -p $builddir
 cd $builddir
@@ -43,11 +35,11 @@ $CMAKEFLAGSALL \
 
 cmake --build $builddir
 
-#builds the fuzzers as oss-fuzz does
+# Builds the fuzzers as oss-fuzz does.
 builddir=$here/build-fuzzers-ossfuzz
 mkdir -p $builddir
 cd $builddir
-CXX="clang++" \
+CXX=$CLANG \
 CXXFLAGS="$CXXFLAGSALL -fsanitize=fuzzer-no-link" cmake \
 cmake $CMAKEFLAGSALL \
 -DFMT_FUZZ_LINKMAIN=Off \
@@ -56,11 +48,11 @@ cmake $CMAKEFLAGSALL \
 cmake --build $builddir
 
 
-#builds fuzzers for local fuzzing with libfuzzer with asan+usan
+# Builds fuzzers for local fuzzing with libfuzzer with asan+usan.
 builddir=$here/build-fuzzers-libfuzzer
 mkdir -p $builddir
 cd $builddir
-CXX="clang++" \
+CXX=$CLANG \
 CXXFLAGS="$CXXFLAGSALL -fsanitize=fuzzer-no-link,address,undefined" cmake \
 cmake $CMAKEFLAGSALL \
 -DFMT_FUZZ_LINKMAIN=Off \
@@ -68,23 +60,11 @@ cmake $CMAKEFLAGSALL \
 
 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 $builddir
-
-#builds a fast fuzzer for making coverage fast
+# Builds a fast fuzzer for making coverage fast.
 builddir=$here/build-fuzzers-fast
 mkdir -p $builddir
 cd $builddir
-CXX="clang++" \
+CXX=$CLANG \
 CXXFLAGS="$CXXFLAGSALL -fsanitize=fuzzer-no-link -O3" cmake \
 cmake $CMAKEFLAGSALL \
 -DFMT_FUZZ_LINKMAIN=Off \
@@ -94,7 +74,7 @@ cmake $CMAKEFLAGSALL \
 cmake --build $builddir
 
 
-#builds fuzzers for local fuzzing with afl
+# Builds fuzzers for local fuzzing with afl.
 builddir=$here/build-fuzzers-afl
 mkdir -p $builddir
 cd $builddir

test/fuzzing/chrono-duration.cc

@@ -0,0 +1,136 @@
+// Copyright (c) 2019, Paul Dreik
+// For the license information refer to format.h.
+
+#include <fmt/chrono.h>
+
+#include <cstdint>
+
+#include "fuzzer-common.h"
+
+template <typename Period, typename Rep>
+void invoke_inner(fmt::string_view format_str, Rep rep) {
+  auto value = std::chrono::duration<Rep, Period>(rep);
+  try {
+#if FMT_FUZZ_FORMAT_TO_STRING
+    std::string message = fmt::format(format_str, value);
+#else
+    auto buf = fmt::memory_buffer();
+    fmt::format_to(std::back_inserter(buf), format_str, value);
+#endif
+  } catch (std::exception&) {
+  }
+}
+
+// Rep is a duration's representation type.
+template <typename Rep>
+void invoke_outer(const uint8_t* data, size_t size, int period) {
+  // Always use a fixed location of the data.
+  static_assert(sizeof(Rep) <= fixed_size, "fixed size is too small");
+  if (size <= fixed_size + 1) return;
+
+  const Rep rep = assign_from_buf<Rep>(data);
+  data += fixed_size;
+  size -= fixed_size;
+
+  // data is already allocated separately in libFuzzer so reading past the end
+  // will most likely be detected anyway.
+  const auto format_str = fmt::string_view(as_chars(data), size);
+
+  // yocto, zepto, zetta and yotta are not handled.
+  switch (period) {
+  case 1:
+    invoke_inner<std::atto>(format_str, rep);
+    break;
+  case 2:
+    invoke_inner<std::femto>(format_str, rep);
+    break;
+  case 3:
+    invoke_inner<std::pico>(format_str, rep);
+    break;
+  case 4:
+    invoke_inner<std::nano>(format_str, rep);
+    break;
+  case 5:
+    invoke_inner<std::micro>(format_str, rep);
+    break;
+  case 6:
+    invoke_inner<std::milli>(format_str, rep);
+    break;
+  case 7:
+    invoke_inner<std::centi>(format_str, rep);
+    break;
+  case 8:
+    invoke_inner<std::deci>(format_str, rep);
+    break;
+  case 9:
+    invoke_inner<std::deca>(format_str, rep);
+    break;
+  case 10:
+    invoke_inner<std::kilo>(format_str, rep);
+    break;
+  case 11:
+    invoke_inner<std::mega>(format_str, rep);
+    break;
+  case 12:
+    invoke_inner<std::giga>(format_str, rep);
+    break;
+  case 13:
+    invoke_inner<std::tera>(format_str, rep);
+    break;
+  case 14:
+    invoke_inner<std::peta>(format_str, rep);
+    break;
+  case 15:
+    invoke_inner<std::exa>(format_str, rep);
+    break;
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  if (size <= 4) return 0;
+
+  const auto representation = data[0];
+  const auto period = data[1];
+  data += 2;
+  size -= 2;
+
+  switch (representation) {
+  case 1:
+    invoke_outer<char>(data, size, period);
+    break;
+  case 2:
+    invoke_outer<signed char>(data, size, period);
+    break;
+  case 3:
+    invoke_outer<unsigned char>(data, size, period);
+    break;
+  case 4:
+    invoke_outer<short>(data, size, period);
+    break;
+  case 5:
+    invoke_outer<unsigned short>(data, size, period);
+    break;
+  case 6:
+    invoke_outer<int>(data, size, period);
+    break;
+  case 7:
+    invoke_outer<unsigned int>(data, size, period);
+    break;
+  case 8:
+    invoke_outer<long>(data, size, period);
+    break;
+  case 9:
+    invoke_outer<unsigned long>(data, size, period);
+    break;
+  case 10:
+    invoke_outer<float>(data, size, period);
+    break;
+  case 11:
+    invoke_outer<double>(data, size, period);
+    break;
+  case 12:
+    invoke_outer<long double>(data, size, period);
+    break;
+  }
+  return 0;
+}

test/fuzzing/chrono-timepoint.cc

@@ -0,0 +1,32 @@
+// Copyright (c) 2021, Paul Dreik
+// For license information refer to format.h.
+#include <fmt/chrono.h>
+
+#include "fuzzer-common.h"
+
+/*
+ * a fuzzer for the chrono timepoints formatters
+ * C is a clock (std::chrono::system_clock etc)
+ */
+template <typename C> void doit(const uint8_t* data, size_t size) {
+  using Rep = typename C::time_point::rep;
+  constexpr auto N = sizeof(Rep);
+  if (size < N) return;
+
+  const auto x = assign_from_buf<Rep>(data);
+  typename C::duration dur{x};
+  typename C::time_point timepoint{dur};
+  data += N;
+  size -= N;
+  data_to_string format_str(data, size);
+
+  std::string message = fmt::format(format_str.get(), timepoint);
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  try {
+    doit<std::chrono::system_clock>(data, size);
+  } catch (...) {
+  }
+  return 0;
+}

test/fuzzing/chrono_duration.cpp

@@ -1,152 +0,0 @@
-// 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, 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, 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/float.cc

@@ -0,0 +1,39 @@
+// A fuzzer for floating-point formatter.
+// For the license information refer to format.h.
+
+#include <fmt/format.h>
+
+#include <cstdint>
+#include <cstdlib>
+#include <limits>
+#include <stdexcept>
+
+#include "fuzzer-common.h"
+
+void check_round_trip(fmt::string_view format_str, double value) {
+  auto buffer = fmt::memory_buffer();
+  fmt::format_to(std::back_inserter(buffer), format_str, value);
+
+  if (std::isnan(value)) {
+    auto nan = std::signbit(value) ? "-nan" : "nan";
+    if (fmt::string_view(buffer.data(), buffer.size()) != nan)
+      throw std::runtime_error("round trip failure");
+    return;
+  }
+
+  buffer.push_back('\0');
+  char* ptr = nullptr;
+  if (std::strtod(buffer.data(), &ptr) != value)
+    throw std::runtime_error("round trip failure");
+  if (ptr + 1 != buffer.end()) throw std::runtime_error("unparsed output");
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  if (size <= sizeof(double) || !std::numeric_limits<double>::is_iec559)
+    return 0;
+  check_round_trip("{}", assign_from_buf<double>(data));
+  // A larger than necessary precision is used to trigger the fallback
+  // formatter.
+  check_round_trip("{:.50g}", assign_from_buf<double>(data));
+  return 0;
+}

test/fuzzing/fuzzer-common.h

@@ -0,0 +1,77 @@
+// Copyright (c) 2019, Paul Dreik
+// For the license information refer to format.h.
+
+#ifndef FUZZER_COMMON_H
+#define FUZZER_COMMON_H
+
+#include <fmt/core.h>
+
+#include <cstdint>  // std::uint8_t
+#include <cstring>  // memcpy
+#include <vector>
+
+// One can format to either a string, or a buffer. The latter is faster, but
+// one may be interested in formatting to a string instead to verify it works
+// as intended. To avoid a combinatoric explosion, select this at compile time
+// instead of dynamically from the fuzz data.
+#define FMT_FUZZ_FORMAT_TO_STRING 0
+
+// If {fmt} is given a buffer that is separately allocated, chances that address
+// sanitizer detects out of bound reads is much higher. However, it slows down
+// the fuzzing.
+#define FMT_FUZZ_SEPARATE_ALLOCATION 1
+
+// The size of the largest possible type in use.
+// To let the the fuzzer mutation be efficient at cross pollinating between
+// different types, use a fixed size format. The same bit pattern, interpreted
+// as another type, is likely interesting.
+constexpr auto fixed_size = 16;
+
+// Casts data to a char pointer.
+template <typename T> inline const char* as_chars(const T* data) {
+  return reinterpret_cast<const char*>(data);
+}
+
+// Casts data to a byte pointer.
+template <typename T> inline const std::uint8_t* as_bytes(const T* data) {
+  return reinterpret_cast<const std::uint8_t*>(data);
+}
+
+// Blits bytes from data to form an (assumed trivially constructible) object
+// of type Item.
+template <class Item> inline Item assign_from_buf(const std::uint8_t* data) {
+  auto item = Item();
+  std::memcpy(&item, data, sizeof(Item));
+  return item;
+}
+
+// Reads a boolean value by looking at the first byte from data.
+template <> inline bool assign_from_buf<bool>(const std::uint8_t* data) {
+  return *data != 0;
+}
+
+struct data_to_string {
+#if FMT_FUZZ_SEPARATE_ALLOCATION
+  std::vector<char> buffer;
+
+  data_to_string(const uint8_t* data, size_t size, bool add_terminator = false)
+      : buffer(size + (add_terminator ? 1 : 0)) {
+    if (size) {
+      std::memcpy(buffer.data(), data, size);
+    }
+  }
+
+  fmt::string_view get() const { return {buffer.data(), buffer.size()}; }
+#else
+  fmt::string_view sv;
+
+  data_to_string(const uint8_t* data, size_t size, bool = false)
+      : str(as_chars(data), size) {}
+
+  fmt::string_view get() const { return sv; }
+#endif
+
+  const char* data() const { return get().data(); }
+};
+
+#endif  // FUZZER_COMMON_H

test/fuzzing/fuzzer_common.h

@@ -1,67 +0,0 @@
-#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.cc

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

test/fuzzing/main.cpp

@@ -1,21 +0,0 @@
-#include <cassert>
-#include <fstream>
-#include <sstream>
-#include <vector>
-#include "fuzzer_common.h"
-
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t* Data, size_t Size);
-int main(int argc, char* argv[]) {
-  for (int i = 1; i < argc; ++i) {
-    std::ifstream in(argv[i]);
-    assert(in);
-    in.seekg(0, std::ios_base::end);
-    const auto pos = in.tellg();
-    assert(pos >= 0);
-    in.seekg(0, std::ios_base::beg);
-    std::vector<char> buf(static_cast<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.cc

@@ -0,0 +1,102 @@
+// Copyright (c) 2019, Paul Dreik
+// For the license information refer to format.h.
+
+#include <fmt/chrono.h>
+
+#include <cstdint>
+#include <type_traits>
+#include <vector>
+
+#include "fuzzer-common.h"
+
+template <typename T>
+void invoke_fmt(const uint8_t* data, size_t size, unsigned arg_name_size) {
+  static_assert(sizeof(T) <= fixed_size, "fixed_size too small");
+  if (size <= fixed_size) return;
+  const T value = assign_from_buf<T>(data);
+  data += fixed_size;
+  size -= fixed_size;
+
+  if (arg_name_size <= 0 || arg_name_size >= size) return;
+  data_to_string arg_name(data, arg_name_size, true);
+  data += arg_name_size;
+  size -= arg_name_size;
+
+  data_to_string format_str(data, size);
+  try {
+#if FMT_FUZZ_FORMAT_TO_STRING
+    std::string message =
+        fmt::format(format_str.get(), fmt::arg(arg_name.data(), value));
+#else
+    fmt::memory_buffer out;
+    fmt::format_to(std::back_inserter(out), format_str.get(),
+                   fmt::arg(arg_name.data(), value));
+#endif
+  } catch (std::exception&) {
+  }
+}
+
+// For dynamic dispatching to an explicit instantiation.
+template <typename Callback> void invoke(int type, Callback callback) {
+  switch (type) {
+  case 0:
+    callback(bool());
+    break;
+  case 1:
+    callback(char());
+    break;
+  case 2:
+    using sc = signed char;
+    callback(sc());
+    break;
+  case 3:
+    using uc = unsigned char;
+    callback(uc());
+    break;
+  case 4:
+    callback(short());
+    break;
+  case 5:
+    using us = unsigned short;
+    callback(us());
+    break;
+  case 6:
+    callback(int());
+    break;
+  case 7:
+    callback(unsigned());
+    break;
+  case 8:
+    callback(long());
+    break;
+  case 9:
+    using ul = unsigned long;
+    callback(ul());
+    break;
+  case 10:
+    callback(float());
+    break;
+  case 11:
+    callback(double());
+    break;
+  case 12:
+    using LD = long double;
+    callback(LD());
+    break;
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  if (size <= 3) return 0;
+
+  // Switch types depending on the first byte of the input.
+  const auto type = data[0] & 0x0F;
+  const unsigned arg_name_size = (data[0] & 0xF0) >> 4;
+  data++;
+  size--;
+
+  invoke(type, [=](auto arg) {
+    invoke_fmt<decltype(arg)>(data, size, arg_name_size);
+  });
+  return 0;
+}

test/fuzzing/named_arg.cpp

@@ -1,128 +0,0 @@
-// 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, 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 + 1);
-  std::memcpy(argnamebuffer.data(), Data, argsize);
-  auto argname = argnamebuffer.data();
-#else
-  auto argname = fmt_fuzzer::as_chars(Data);
-#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, 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.cc

@@ -0,0 +1,92 @@
+// Copyright (c) 2019, Paul Dreik
+// For the license information refer to format.h.
+
+#include <fmt/chrono.h>
+
+#include <cstdint>
+#include <exception>
+
+#include "fuzzer-common.h"
+
+template <typename T, typename Repr> const T* from_repr(const Repr& r) {
+  return &r;
+}
+
+template <> const std::tm* from_repr<std::tm>(const std::time_t& t) {
+  return std::localtime(&t);
+}
+
+template <typename T, typename Repr = T>
+void invoke_fmt(const uint8_t* data, size_t size) {
+  static_assert(sizeof(Repr) <= fixed_size, "Nfixed is too small");
+  if (size <= fixed_size) return;
+  auto repr = assign_from_buf<Repr>(data);
+  const T* value = from_repr<T>(repr);
+  if (!value) return;
+  data += fixed_size;
+  size -= fixed_size;
+  data_to_string format_str(data, size);
+  try {
+#if FMT_FUZZ_FORMAT_TO_STRING
+    std::string message = fmt::format(format_str.get(), *value);
+#else
+    fmt::memory_buffer message;
+    fmt::format_to(message, format_str.get(), *value);
+#endif
+  } catch (std::exception&) {
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  if (size <= 3) return 0;
+
+  const auto first = data[0];
+  data++;
+  size--;
+
+  switch (first) {
+  case 0:
+    invoke_fmt<bool>(data, size);
+    break;
+  case 1:
+    invoke_fmt<char>(data, size);
+    break;
+  case 2:
+    invoke_fmt<unsigned char>(data, size);
+    break;
+  case 3:
+    invoke_fmt<signed char>(data, size);
+    break;
+  case 4:
+    invoke_fmt<short>(data, size);
+    break;
+  case 5:
+    invoke_fmt<unsigned short>(data, size);
+    break;
+  case 6:
+    invoke_fmt<int>(data, size);
+    break;
+  case 7:
+    invoke_fmt<unsigned int>(data, size);
+    break;
+  case 8:
+    invoke_fmt<long>(data, size);
+    break;
+  case 9:
+    invoke_fmt<unsigned long>(data, size);
+    break;
+  case 10:
+    invoke_fmt<float>(data, size);
+    break;
+  case 11:
+    invoke_fmt<double>(data, size);
+    break;
+  case 12:
+    invoke_fmt<long double>(data, size);
+    break;
+  case 13:
+    invoke_fmt<std::tm, std::time_t>(data, size);
+    break;
+  }
+  return 0;
+}

test/fuzzing/one_arg.cpp

@@ -1,131 +0,0 @@
-// 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, 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, 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, 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

@@ -1,116 +0,0 @@
-// 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, 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, 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.cc

@@ -0,0 +1,106 @@
+// Copyright (c) 2019, Paul Dreik
+// For the license information refer to format.h.
+
+#include <fmt/format.h>
+
+#include <cstdint>
+#include <exception>
+#include <string>
+
+#include "fuzzer-common.h"
+
+template <typename Item1, typename Item2>
+void invoke_fmt(const uint8_t* data, size_t size) {
+  static_assert(sizeof(Item1) <= fixed_size, "size1 exceeded");
+  static_assert(sizeof(Item2) <= fixed_size, "size2 exceeded");
+  if (size <= fixed_size + fixed_size) return;
+
+  const Item1 item1 = assign_from_buf<Item1>(data);
+  data += fixed_size;
+  size -= fixed_size;
+
+  const Item2 item2 = assign_from_buf<Item2>(data);
+  data += fixed_size;
+  size -= fixed_size;
+
+  auto format_str = fmt::string_view(as_chars(data), size);
+#if FMT_FUZZ_FORMAT_TO_STRING
+  std::string message = fmt::format(format_str, item1, item2);
+#else
+  fmt::memory_buffer message;
+  fmt::format_to(message, format_str, item1, item2);
+#endif
+}
+
+// For dynamic dispatching to an explicit instantiation.
+template <typename Callback> void invoke(int index, Callback callback) {
+  switch (index) {
+  case 0:
+    callback(bool());
+    break;
+  case 1:
+    callback(char());
+    break;
+  case 2:
+    using sc = signed char;
+    callback(sc());
+    break;
+  case 3:
+    using uc = unsigned char;
+    callback(uc());
+    break;
+  case 4:
+    callback(short());
+    break;
+  case 5:
+    using us = unsigned short;
+    callback(us());
+    break;
+  case 6:
+    callback(int());
+    break;
+  case 7:
+    callback(unsigned());
+    break;
+  case 8:
+    callback(long());
+    break;
+  case 9:
+    using ul = unsigned long;
+    callback(ul());
+    break;
+  case 10:
+    callback(float());
+    break;
+  case 11:
+    callback(double());
+    break;
+  case 12:
+    using LD = long double;
+    callback(LD());
+    break;
+  case 13:
+    using ptr = void*;
+    callback(ptr());
+    break;
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  if (size <= 3) return 0;
+
+  // Switch types depending on the first byte of the input.
+  const auto type1 = data[0] & 0x0F;
+  const auto type2 = (data[0] & 0xF0) >> 4;
+  data++;
+  size--;
+  try {
+    invoke(type1, [=](auto param1) {
+      invoke(type2, [=](auto param2) {
+        invoke_fmt<decltype(param1), decltype(param2)>(data, size);
+      });
+    });
+  } catch (std::exception&) {
+  }
+  return 0;
+}

test/fuzzing/two_args.cpp

@@ -1,112 +0,0 @@
-// 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, 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, 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

@@ -1,75 +0,0 @@
-// 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("100000000000.0", 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));
-  EXPECT_EQ("0.1", fmt::format("{}", 0.1f));
-  EXPECT_EQ("0.10000000149011612", fmt::format("{}", double(0.1f)));
-}
-
-TEST(GrisuTest, ZeroPrecision) { EXPECT_EQ("1", fmt::format("{:.0}", 1.0)); }
-
-TEST(GrisuTest, Fallback) {
-  EXPECT_EQ("1e+23", fmt::format("{}", 1e23));
-  EXPECT_EQ("9e-265", fmt::format("{}", 9e-265));
-  EXPECT_EQ("5.423717798060526e+125",
-            fmt::format("{}", 5.423717798060526e+125));
-  EXPECT_EQ("1.372371880954233e-288",
-            fmt::format("{}", 1.372371880954233e-288));
-  EXPECT_EQ("55388492.622190244", fmt::format("{}", 55388492.622190244));
-  EXPECT_EQ("2.2506787569811123e-253",
-            fmt::format("{}", 2.2506787569811123e-253));
-  EXPECT_EQ("1103618912042992.8", fmt::format("{}", 1103618912042992.8));
-  // pow(2, -25) - assymetric boundaries:
-  EXPECT_EQ("2.9802322387695312e-08",
-            fmt::format("{}", 2.9802322387695312e-08));
-}

test/gtest-extra-test.cc

@@ -9,31 +9,18 @@
 
 #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 "fmt/os.h"
 #include "util.h"
 
-namespace {
-
-// This is used to suppress coverity warnings about untrusted values.
-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));
-  return result;
-}
-
 // Tests that assertion macros evaluate their arguments exactly once.
-class SingleEvaluationTest : public ::testing::Test {
+namespace {
+class single_evaluation_test : public ::testing::Test {
  protected:
-  SingleEvaluationTest() {
+  single_evaluation_test() {
     p_ = s_;
     a_ = 0;
     b_ = 0;
@@ -45,11 +32,12 @@ class SingleEvaluationTest : public ::testing::Test {
   static int a_;
   static int b_;
 };
+}  // namespace
 
-const char* const SingleEvaluationTest::s_ = "01234";
-const char* SingleEvaluationTest::p_;
-int SingleEvaluationTest::a_;
-int SingleEvaluationTest::b_;
+const char* const single_evaluation_test::s_ = "01234";
+const char* single_evaluation_test::p_;
+int single_evaluation_test::a_;
+int single_evaluation_test::b_;
 
 void do_nothing() {}
 
@@ -61,7 +49,7 @@ FMT_NORETURN void throw_system_error() {
 
 // Tests that when EXPECT_THROW_MSG fails, it evaluates its message argument
 // exactly once.
-TEST_F(SingleEvaluationTest, FailedEXPECT_THROW_MSG) {
+TEST_F(single_evaluation_test, failed_expect_throw_msg) {
   EXPECT_NONFATAL_FAILURE(
       EXPECT_THROW_MSG(throw_exception(), std::exception, p_++), "01234");
   EXPECT_EQ(s_ + 1, p_);
@@ -69,14 +57,14 @@ 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) {
+TEST_F(single_evaluation_test, failed_expect_system_error) {
   EXPECT_NONFATAL_FAILURE(EXPECT_SYSTEM_ERROR(throw_system_error(), EDOM, p_++),
                           "01234");
   EXPECT_EQ(s_ + 1, p_);
 }
 
 // Tests that assertion arguments are evaluated exactly once.
-TEST_F(SingleEvaluationTest, ExceptionTests) {
+TEST_F(single_evaluation_test, exception_tests) {
   // successful EXPECT_THROW_MSG
   EXPECT_THROW_MSG(
       {  // NOLINT
@@ -116,7 +104,7 @@ TEST_F(SingleEvaluationTest, ExceptionTests) {
   EXPECT_EQ(4, b_);
 }
 
-TEST_F(SingleEvaluationTest, SystemErrorTests) {
+TEST_F(single_evaluation_test, system_error_tests) {
   // successful EXPECT_SYSTEM_ERROR
   EXPECT_SYSTEM_ERROR(
       {  // NOLINT
@@ -159,14 +147,14 @@ TEST_F(SingleEvaluationTest, SystemErrorTests) {
 #if FMT_USE_FCNTL
 // Tests that when EXPECT_WRITE fails, it evaluates its message argument
 // exactly once.
-TEST_F(SingleEvaluationTest, FailedEXPECT_WRITE) {
+TEST_F(single_evaluation_test, failed_expect_write) {
   EXPECT_NONFATAL_FAILURE(EXPECT_WRITE(stdout, std::printf("test"), p_++),
                           "01234");
   EXPECT_EQ(s_ + 1, p_);
 }
 
 // Tests that assertion arguments are evaluated exactly once.
-TEST_F(SingleEvaluationTest, WriteTests) {
+TEST_F(single_evaluation_test, write_tests) {
   // successful EXPECT_WRITE
   EXPECT_WRITE(
       stdout,
@@ -192,7 +180,7 @@ TEST_F(SingleEvaluationTest, WriteTests) {
 }
 
 // Tests EXPECT_WRITE.
-TEST(ExpectTest, EXPECT_WRITE) {
+TEST(gtest_extra_test, expect_write) {
   EXPECT_WRITE(stdout, do_nothing(), "");
   EXPECT_WRITE(stdout, std::printf("test"), "test");
   EXPECT_WRITE(stderr, std::fprintf(stderr, "test"), "test");
@@ -201,7 +189,7 @@ TEST(ExpectTest, EXPECT_WRITE) {
                           "  Actual: that");
 }
 
-TEST(StreamingAssertionsTest, EXPECT_WRITE) {
+TEST(gtest_extra_test, expect_write_streaming) {
   EXPECT_WRITE(stdout, std::printf("test"), "test") << "unexpected failure";
   EXPECT_NONFATAL_FAILURE(EXPECT_WRITE(stdout, std::printf("test"), "other")
                               << "expected failure",
@@ -211,7 +199,7 @@ TEST(StreamingAssertionsTest, EXPECT_WRITE) {
 
 // Tests that the compiler will not complain about unreachable code in the
 // EXPECT_THROW_MSG macro.
-TEST(ExpectThrowTest, DoesNotGenerateUnreachableCodeWarning) {
+TEST(gtest_extra_test, expect_throw_no_unreachable_code_warning) {
   int n = 0;
   using std::runtime_error;
   EXPECT_THROW_MSG(throw runtime_error(""), runtime_error, "");
@@ -223,7 +211,7 @@ TEST(ExpectThrowTest, DoesNotGenerateUnreachableCodeWarning) {
 
 // Tests that the compiler will not complain about unreachable code in the
 // EXPECT_SYSTEM_ERROR macro.
-TEST(ExpectSystemErrorTest, DoesNotGenerateUnreachableCodeWarning) {
+TEST(gtest_extra_test, expect_system_error_no_unreachable_code_warning) {
   int n = 0;
   EXPECT_SYSTEM_ERROR(throw fmt::system_error(EDOM, "test"), EDOM, "test");
   EXPECT_NONFATAL_FAILURE(EXPECT_SYSTEM_ERROR(n++, EDOM, ""), "");
@@ -233,7 +221,7 @@ TEST(ExpectSystemErrorTest, DoesNotGenerateUnreachableCodeWarning) {
       "");
 }
 
-TEST(AssertionSyntaxTest, ExceptionAssertionBehavesLikeSingleStatement) {
+TEST(gtest_extra_test, expect_throw_behaves_like_single_statement) {
   if (::testing::internal::AlwaysFalse())
     EXPECT_THROW_MSG(do_nothing(), std::exception, "");
 
@@ -243,7 +231,7 @@ TEST(AssertionSyntaxTest, ExceptionAssertionBehavesLikeSingleStatement) {
     do_nothing();
 }
 
-TEST(AssertionSyntaxTest, SystemErrorAssertionBehavesLikeSingleStatement) {
+TEST(gtest_extra_test, expect_system_error_behaves_like_single_statement) {
   if (::testing::internal::AlwaysFalse())
     EXPECT_SYSTEM_ERROR(do_nothing(), EDOM, "");
 
@@ -253,7 +241,7 @@ TEST(AssertionSyntaxTest, SystemErrorAssertionBehavesLikeSingleStatement) {
     do_nothing();
 }
 
-TEST(AssertionSyntaxTest, WriteAssertionBehavesLikeSingleStatement) {
+TEST(gtest_extra_test, expect_write_behaves_like_single_statement) {
   if (::testing::internal::AlwaysFalse())
     EXPECT_WRITE(stdout, std::printf("x"), "x");
 
@@ -264,7 +252,7 @@ TEST(AssertionSyntaxTest, WriteAssertionBehavesLikeSingleStatement) {
 }
 
 // Tests EXPECT_THROW_MSG.
-TEST(ExpectTest, EXPECT_THROW_MSG) {
+TEST(gtest_extra_test, expect_throw_msg) {
   EXPECT_THROW_MSG(throw_exception(), std::exception, "test");
   EXPECT_NONFATAL_FAILURE(
       EXPECT_THROW_MSG(throw_exception(), std::logic_error, "test"),
@@ -282,15 +270,15 @@ TEST(ExpectTest, EXPECT_THROW_MSG) {
 }
 
 // Tests EXPECT_SYSTEM_ERROR.
-TEST(ExpectTest, EXPECT_SYSTEM_ERROR) {
+TEST(gtest_extra_test, expect_system_error) {
   EXPECT_SYSTEM_ERROR(throw_system_error(), EDOM, "test");
   EXPECT_NONFATAL_FAILURE(
       EXPECT_SYSTEM_ERROR(throw_exception(), EDOM, "test"),
       "Expected: throw_exception() throws an exception of "
-      "type fmt::system_error.\n  Actual: it throws a different type.");
+      "type std::system_error.\n  Actual: it throws a different type.");
   EXPECT_NONFATAL_FAILURE(
       EXPECT_SYSTEM_ERROR(do_nothing(), EDOM, "test"),
-      "Expected: do_nothing() throws an exception of type fmt::system_error.\n"
+      "Expected: do_nothing() throws an exception of type std::system_error.\n"
       "  Actual: it throws nothing.");
   EXPECT_NONFATAL_FAILURE(
       EXPECT_SYSTEM_ERROR(throw_system_error(), EDOM, "other"),
@@ -298,11 +286,11 @@ TEST(ExpectTest, EXPECT_SYSTEM_ERROR) {
           "throw_system_error() throws an exception with a different message.\n"
           "Expected: {}\n"
           "  Actual: {}",
-          format_system_error(EDOM, "other"),
-          format_system_error(EDOM, "test")));
+          system_error_message(EDOM, "other"),
+          system_error_message(EDOM, "test")));
 }
 
-TEST(StreamingAssertionsTest, EXPECT_THROW_MSG) {
+TEST(gtest_extra_test, expect_throw_msg_streaming) {
   EXPECT_THROW_MSG(throw_exception(), std::exception, "test")
       << "unexpected failure";
   EXPECT_NONFATAL_FAILURE(
@@ -311,7 +299,7 @@ TEST(StreamingAssertionsTest, EXPECT_THROW_MSG) {
       "expected failure");
 }
 
-TEST(StreamingAssertionsTest, EXPECT_SYSTEM_ERROR) {
+TEST(gtest_extra_test, expect_system_error_streaming) {
   EXPECT_SYSTEM_ERROR(throw_system_error(), EDOM, "test")
       << "unexpected failure";
   EXPECT_NONFATAL_FAILURE(
@@ -320,31 +308,19 @@ TEST(StreamingAssertionsTest, EXPECT_SYSTEM_ERROR) {
       "expected failure");
 }
 
-TEST(UtilTest, FormatSystemError) {
-  fmt::memory_buffer out;
-  fmt::format_system_error(out, EDOM, "test message");
-  EXPECT_EQ(to_string(out), format_system_error(EDOM, "test message"));
-}
-
 #if FMT_USE_FCNTL
 
 using fmt::buffered_file;
-using fmt::error_code;
 using fmt::file;
 
-TEST(ErrorCodeTest, Ctor) {
-  EXPECT_EQ(error_code().get(), 0);
-  EXPECT_EQ(error_code(42).get(), 42);
-}
-
-TEST(OutputRedirectTest, ScopedRedirect) {
+TEST(output_redirect_test, scoped_redirect) {
   file read_end, write_end;
   file::pipe(read_end, write_end);
   {
     buffered_file file(write_end.fdopen("w"));
     std::fprintf(file.get(), "[[[");
     {
-      OutputRedirect redir(file.get());
+      output_redirect redir(file.get());
       std::fprintf(file.get(), "censored");
     }
     std::fprintf(file.get(), "]]]");
@@ -352,8 +328,8 @@ TEST(OutputRedirectTest, ScopedRedirect) {
   EXPECT_READ(read_end, "[[[]]]");
 }
 
-// Test that OutputRedirect handles errors in flush correctly.
-TEST(OutputRedirectTest, FlushErrorInCtor) {
+// Test that output_redirect handles errors in flush correctly.
+TEST(output_redirect_test, flush_error_in_ctor) {
   file read_end, write_end;
   file::pipe(read_end, write_end);
   int write_fd = write_end.descriptor();
@@ -362,47 +338,47 @@ TEST(OutputRedirectTest, FlushErrorInCtor) {
   // Put a character in a file buffer.
   EXPECT_EQ('x', fputc('x', f.get()));
   FMT_POSIX(close(write_fd));
-  std::unique_ptr<OutputRedirect> redir{nullptr};
-  EXPECT_SYSTEM_ERROR_NOASSERT(redir.reset(new OutputRedirect(f.get())), EBADF,
+  std::unique_ptr<output_redirect> redir{nullptr};
+  EXPECT_SYSTEM_ERROR_NOASSERT(redir.reset(new output_redirect(f.get())), EBADF,
                                "cannot flush stream");
   redir.reset(nullptr);
   write_copy.dup2(write_fd);  // "undo" close or dtor will fail
 }
 
-TEST(OutputRedirectTest, DupErrorInCtor) {
+TEST(output_redirect_test, dup_error_in_ctor) {
   buffered_file f = open_buffered_file();
   int fd = (f.fileno)();
   file copy = file::dup(fd);
   FMT_POSIX(close(fd));
-  std::unique_ptr<OutputRedirect> redir{nullptr};
+  std::unique_ptr<output_redirect> redir{nullptr};
   EXPECT_SYSTEM_ERROR_NOASSERT(
-      redir.reset(new OutputRedirect(f.get())), EBADF,
+      redir.reset(new output_redirect(f.get())), EBADF,
       fmt::format("cannot duplicate file descriptor {}", fd));
   copy.dup2(fd);  // "undo" close or dtor will fail
 }
 
-TEST(OutputRedirectTest, RestoreAndRead) {
+TEST(output_redirect_test, restore_and_read) {
   file read_end, write_end;
   file::pipe(read_end, write_end);
   buffered_file file(write_end.fdopen("w"));
   std::fprintf(file.get(), "[[[");
-  OutputRedirect redir(file.get());
+  output_redirect redir(file.get());
   std::fprintf(file.get(), "censored");
-  EXPECT_EQ("censored", sanitize(redir.restore_and_read()));
-  EXPECT_EQ("", sanitize(redir.restore_and_read()));
+  EXPECT_EQ("censored", redir.restore_and_read());
+  EXPECT_EQ("", redir.restore_and_read());
   std::fprintf(file.get(), "]]]");
   file = buffered_file();
   EXPECT_READ(read_end, "[[[]]]");
 }
 
 // Test that OutputRedirect handles errors in flush correctly.
-TEST(OutputRedirectTest, FlushErrorInRestoreAndRead) {
+TEST(output_redirect_test, flush_error_in_restore_and_read) {
   file read_end, write_end;
   file::pipe(read_end, write_end);
   int write_fd = write_end.descriptor();
   file write_copy = write_end.dup(write_fd);
   buffered_file f = write_end.fdopen("w");
-  OutputRedirect redir(f.get());
+  output_redirect redir(f.get());
   // Put a character in a file buffer.
   EXPECT_EQ('x', fputc('x', f.get()));
   FMT_POSIX(close(write_fd));
@@ -411,13 +387,13 @@ TEST(OutputRedirectTest, FlushErrorInRestoreAndRead) {
   write_copy.dup2(write_fd);  // "undo" close or dtor will fail
 }
 
-TEST(OutputRedirectTest, ErrorInDtor) {
+TEST(output_redirect_test, error_in_dtor) {
   file read_end, write_end;
   file::pipe(read_end, write_end);
   int write_fd = write_end.descriptor();
   file write_copy = write_end.dup(write_fd);
   buffered_file f = write_end.fdopen("w");
-  std::unique_ptr<OutputRedirect> redir(new OutputRedirect(f.get()));
+  std::unique_ptr<output_redirect> redir(new output_redirect(f.get()));
   // Put a character in a file buffer.
   EXPECT_EQ('x', fputc('x', f.get()));
   EXPECT_WRITE(
@@ -430,10 +406,8 @@ TEST(OutputRedirectTest, ErrorInDtor) {
         FMT_POSIX(close(write_fd));
         SUPPRESS_ASSERT(redir.reset(nullptr));
       },
-      format_system_error(EBADF, "cannot flush stream"));
+      system_error_message(EBADF, "cannot flush stream"));
   write_copy.dup2(write_fd);  // "undo" close or dtor of buffered_file will fail
 }
 
-#endif  // FMT_USE_FILE_DESCRIPTORS
-
-}  // namespace
+#endif  // FMT_USE_FCNTL

test/gtest-extra.cc

@@ -11,24 +11,7 @@
 
 using fmt::file;
 
-void OutputRedirect::flush() {
-#  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");
-}
-
-void OutputRedirect::restore() {
-  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) {
+output_redirect::output_redirect(FILE* f) : file_(f) {
   flush();
   int fd = FMT_POSIX(fileno(f));
   // Create a file object referring to the original file.
@@ -40,7 +23,7 @@ OutputRedirect::OutputRedirect(FILE* f) : file_(f) {
   write_end.dup2(fd);
 }
 
-OutputRedirect::~OutputRedirect() FMT_NOEXCEPT {
+output_redirect::~output_redirect() FMT_NOEXCEPT {
   try {
     restore();
   } catch (const std::exception& e) {
@@ -48,7 +31,23 @@ OutputRedirect::~OutputRedirect() FMT_NOEXCEPT {
   }
 }
 
-std::string OutputRedirect::restore_and_read() {
+void output_redirect::flush() {
+  int result = 0;
+  do {
+    result = fflush(file_);
+  } while (result == EOF && errno == EINTR);
+  if (result != 0) throw fmt::system_error(errno, "cannot flush stream");
+}
+
+void output_redirect::restore() {
+  if (original_.descriptor() == -1) return;  // Already restored.
+  flush();
+  // Restore the original file.
+  original_.dup2(FMT_POSIX(fileno(file_)));
+  original_.close();
+}
+
+std::string output_redirect::restore_and_read() {
   // Restore output.
   restore();
 
@@ -79,9 +78,3 @@ std::string read(file& f, size_t count) {
 }
 
 #endif  // FMT_USE_FCNTL
-
-std::string format_system_error(int error_code, fmt::string_view message) {
-  fmt::memory_buffer out;
-  format_system_error(out, error_code, message);
-  return to_string(out);
-}

test/gtest-extra.h

@@ -8,10 +8,17 @@
 #ifndef FMT_GTEST_EXTRA_H_
 #define FMT_GTEST_EXTRA_H_
 
+#include <stdlib.h>  // _invalid_parameter_handler
+
 #include <string>
 
-#include "fmt/os.h"
-#include "gmock.h"
+#ifdef FMT_MODULE_TEST
+import fmt;
+#else
+#  include "fmt/os.h"
+#endif  // FMG_MODULE_TEST
+
+#include "gmock/gmock.h"
 
 #define FMT_TEST_THROW_(statement, expected_exception, expected_message, fail) \
   GTEST_AMBIGUOUS_ELSE_BLOCKER_                                                \
@@ -51,30 +58,35 @@
   FMT_TEST_THROW_(statement, expected_exception, expected_message,        \
                   GTEST_NONFATAL_FAILURE_)
 
-std::string format_system_error(int error_code, fmt::string_view message);
+inline std::string system_error_message(int error_code,
+                                        const std::string& message) {
+  auto ec = std::error_code(error_code, std::generic_category());
+  return std::system_error(ec, message).what();
+}
 
 #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, std::system_error,            \
+                   system_error_message(error_code, message))
 
 #if FMT_USE_FCNTL
 
 // Captures file output by redirecting it to a pipe.
 // The output it can handle is limited by the pipe capacity.
-class OutputRedirect {
+class output_redirect {
  private:
   FILE* file_;
   fmt::file original_;  // Original file passed to redirector.
   fmt::file read_end_;  // Read end of the pipe where the output is redirected.
 
-  GTEST_DISALLOW_COPY_AND_ASSIGN_(OutputRedirect);
-
   void flush();
   void restore();
 
  public:
-  explicit OutputRedirect(FILE* file);
-  ~OutputRedirect() FMT_NOEXCEPT;
+  explicit output_redirect(FILE* file);
+  ~output_redirect() FMT_NOEXCEPT;
+
+  output_redirect(const output_redirect&) = delete;
+  void operator=(const output_redirect&) = delete;
 
   // Restores the original file, reads output from the pipe into a string
   // and returns it.
@@ -85,7 +97,7 @@ class OutputRedirect {
     GTEST_AMBIGUOUS_ELSE_BLOCKER_                                              \
     if (::testing::AssertionResult gtest_ar = ::testing::AssertionSuccess()) { \
       std::string gtest_expected_output = expected_output;                     \
-      OutputRedirect gtest_redir(file);                                        \
+      output_redirect 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) {                             \
@@ -106,7 +118,7 @@ class OutputRedirect {
 
 // Suppresses Windows assertions on invalid file descriptors, making
 // POSIX functions return proper error codes instead of crashing on Windows.
-class SuppressAssert {
+class suppress_assert {
  private:
   _invalid_parameter_handler original_handler_;
   int original_report_mode_;
@@ -115,19 +127,20 @@ class SuppressAssert {
                                        const wchar_t*, unsigned, uintptr_t) {}
 
  public:
-  SuppressAssert()
+  suppress_assert()
       : original_handler_(
             _set_invalid_parameter_handler(handle_invalid_parameter)),
         original_report_mode_(_CrtSetReportMode(_CRT_ASSERT, 0)) {}
-  ~SuppressAssert() {
+  ~suppress_assert() {
     _set_invalid_parameter_handler(original_handler_);
     _CrtSetReportMode(_CRT_ASSERT, original_report_mode_);
+    (void)original_report_mode_;
   }
 };
 
 #    define SUPPRESS_ASSERT(statement) \
       {                                \
-        SuppressAssert sa;             \
+        suppress_assert sa;            \
         statement;                     \
       }
 #  else
@@ -141,16 +154,17 @@ class SuppressAssert {
 std::string read(fmt::file& f, size_t count);
 
 #  define EXPECT_READ(file, expected_content) \
-    EXPECT_EQ(expected_content, \
+    EXPECT_EQ(expected_content,               \
               read(file, fmt::string_view(expected_content).size()))
 
 #else
-#  define EXPECT_WRITE(file, statement, expected_output) SUCCEED()
+#  define EXPECT_WRITE(file, statement, expected_output) \
+    do {                                                 \
+      (void)(file);                                      \
+      (void)(statement);                                 \
+      (void)(expected_output);                           \
+      SUCCEED();                                         \
+    } while (false)
 #endif  // FMT_USE_FCNTL
 
-template <typename Mock> struct ScopedMock : testing::StrictMock<Mock> {
-  ScopedMock() { Mock::instance = this; }
-  ~ScopedMock() { Mock::instance = nullptr; }
-};
-
 #endif  // FMT_GTEST_EXTRA_H_

test/gtest/.clang-format

@@ -0,0 +1,3 @@
+# Disable clang-format here
+DisableFormat: true
+SortIncludes: Never

test/gtest/CMakeLists.txt

@@ -0,0 +1,38 @@
+#------------------------------------------------------------------------------
+# Build the google test library
+
+# We compile Google Test ourselves instead of using pre-compiled libraries.
+# See the Google Test FAQ "Why is it not recommended to install a
+# pre-compiled copy of Google Test (for example, into /usr/local)?"
+# at http://code.google.com/p/googletest/wiki/FAQ for more details.
+add_library(gtest STATIC
+  gmock-gtest-all.cc gmock/gmock.h gtest/gtest.h gtest/gtest-spi.h)
+target_compile_definitions(gtest PUBLIC GTEST_HAS_STD_WSTRING=1)
+target_include_directories(gtest SYSTEM PUBLIC .)
+
+find_package(Threads)
+if (Threads_FOUND)
+  target_link_libraries(gtest ${CMAKE_THREAD_LIBS_INIT})
+else ()
+  target_compile_definitions(gtest PUBLIC GTEST_HAS_PTHREAD=0)
+endif ()
+
+# Workaround GTest bug https://github.com/google/googletest/issues/705.
+check_cxx_compiler_flag(
+  -fno-delete-null-pointer-checks HAVE_FNO_DELETE_NULL_POINTER_CHECKS)
+if (HAVE_FNO_DELETE_NULL_POINTER_CHECKS)
+  target_compile_options(gtest PUBLIC -fno-delete-null-pointer-checks)
+endif ()
+
+if (MSVC)
+  # Disable MSVC warnings of _CRT_INSECURE_DEPRECATE functions.
+  target_compile_definitions(gtest PRIVATE _CRT_SECURE_NO_WARNINGS)
+  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+    # Disable MSVC warnings of POSIX functions.
+    target_compile_options(gtest PUBLIC -Wno-deprecated-declarations)
+  endif ()
+endif ()
+
+# Silence MSVC tr1 deprecation warning in gmock.
+target_compile_definitions(gtest
+  PUBLIC _SILENCE_TR1_NAMESPACE_DEPRECATION_WARNING=1)

test/gtest/gtest/gtest-spi.h

@@ -26,17 +26,21 @@
 // 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.
-//
-// Author: wan@google.com (Zhanyong Wan)
+
 //
 // Utilities for testing Google Test itself and code that uses Google Test
 // (e.g. frameworks built on top of Google Test).
 
-#ifndef GTEST_INCLUDE_GTEST_GTEST_SPI_H_
-#define GTEST_INCLUDE_GTEST_GTEST_SPI_H_
+// GOOGLETEST_CM0004 DO NOT DELETE
+
+#ifndef GOOGLETEST_INCLUDE_GTEST_GTEST_SPI_H_
+#define GOOGLETEST_INCLUDE_GTEST_GTEST_SPI_H_
 
 #include "gtest/gtest.h"
 
+GTEST_DISABLE_MSC_WARNINGS_PUSH_(4251 \
+/* class A needs to have dll-interface to be used by clients of class B */)
+
 namespace testing {
 
 // This helper class can be used to mock out Google Test failure reporting
@@ -68,14 +72,15 @@ class GTEST_API_ ScopedFakeTestPartResultReporter
                                    TestPartResultArray* result);
 
   // The d'tor restores the previous test part result reporter.
-  virtual ~ScopedFakeTestPartResultReporter();
+  ~ScopedFakeTestPartResultReporter() override;
 
   // Appends the TestPartResult object to the TestPartResultArray
   // received in the constructor.
   //
   // This method is from the TestPartResultReporterInterface
   // interface.
-  virtual void ReportTestPartResult(const TestPartResult& result);
+  void ReportTestPartResult(const TestPartResult& result) override;
+
  private:
   void Init();
 
@@ -97,13 +102,12 @@ class GTEST_API_ SingleFailureChecker {
  public:
   // The constructor remembers the arguments.
   SingleFailureChecker(const TestPartResultArray* results,
-                       TestPartResult::Type type,
-                       const string& substr);
+                       TestPartResult::Type type, const std::string& substr);
   ~SingleFailureChecker();
  private:
   const TestPartResultArray* const results_;
   const TestPartResult::Type type_;
-  const string substr_;
+  const std::string substr_;
 
   GTEST_DISALLOW_COPY_AND_ASSIGN_(SingleFailureChecker);
 };
@@ -112,6 +116,8 @@ class GTEST_API_ SingleFailureChecker {
 
 }  // namespace testing
 
+GTEST_DISABLE_MSC_WARNINGS_POP_()  //  4251
+
 // A set of macros for testing Google Test assertions or code that's expected
 // to generate Google Test fatal failures.  It verifies that the given
 // statement will cause exactly one fatal Google Test failure with 'substr'
@@ -229,4 +235,4 @@ class GTEST_API_ SingleFailureChecker {
     }\
   } while (::testing::internal::AlwaysFalse())
 
-#endif  // GTEST_INCLUDE_GTEST_GTEST_SPI_H_
+#endif  // GOOGLETEST_INCLUDE_GTEST_GTEST_SPI_H_