Update version

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 3.1.2 to 4.0.0.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](0b7f8abb15...c7d193f32e)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.clang-format

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

.github/dependabot.yml

@@ -0,0 +1,8 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions" # Necessary to update action hashs	
+    directory: "/"
+    schedule:
+      interval: "monthly"
+    # Allow up to 3 opened pull requests for github-actions versions
+    open-pull-requests-limit: 3

.github/issue_template.md

@@ -0,0 +1,6 @@
+<!--
+Please make sure that the problem reproduces on the current master before
+submitting an issue.
+If possible please provide a repro on Compiler Explorer:
+https://godbolt.org/z/fxccbh53W.
+-->

.github/pull_request_template.md

@@ -0,0 +1,7 @@
+<!--
+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 to license your contribution(s)
+under the terms outlined in LICENSE.rst and represent that you have the right
+to do so.
+-->

.github/workflows/cifuzz.yml

@@ -0,0 +1,30 @@
+name: CIFuzz
+on: [pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  Fuzzing:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Build Fuzzers
+      id: build
+      uses: google/oss-fuzz/infra/cifuzz/actions/build_fuzzers@061583ebb5a96653e42feb3a97ee513eedc18078 # master
+      with:
+        oss-fuzz-project-name: 'fmt'
+        dry-run: false
+        language: c++
+    - name: Run Fuzzers
+      uses: google/oss-fuzz/infra/cifuzz/actions/run_fuzzers@061583ebb5a96653e42feb3a97ee513eedc18078 # master
+      with:
+        oss-fuzz-project-name: 'fmt'
+        fuzz-seconds: 300
+        dry-run: false
+        language: c++
+    - name: Upload Crash
+      uses: actions/upload-artifact@c7d193f32edcb7bfad88892161225aeda64e9392 # v4.0.0
+      if: failure() && steps.build.outcome == 'success'
+      with:
+        name: artifacts
+        path: ./out/artifacts

.github/workflows/doc.yml

@@ -0,0 +1,35 @@
+name: doc
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+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@8ade135a41bc03ea155e62e844d188df1ea18608 # v4.1.0
+
+    - name: Add ubuntu mirrors
+      run: |
+        # Github Actions caching proxy is at times unreliable
+        # see https://github.com/actions/runner-images/issues/7048
+        printf 'http://azure.archive.ubuntu.com/ubuntu\tpriority:1\n' | sudo tee /etc/apt/mirrors.txt
+        curl http://mirrors.ubuntu.com/mirrors.txt | sudo tee --append /etc/apt/mirrors.txt
+        sudo sed -i 's~http://azure.archive.ubuntu.com/ubuntu/~mirror+file:/etc/apt/mirrors.txt~' /etc/apt/sources.list
+
+    - 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/lint.yml

@@ -0,0 +1,26 @@
+name: lint
+
+on:
+  pull_request:
+    paths:
+      - '**.h'
+      - '**.cc'
+
+permissions:
+  contents: read
+
+jobs:
+  format_code:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Install clang-format
+      uses: aminya/setup-cpp@v1
+      with:
+        clangformat: 17.0.5
+
+    - name: Run clang-format
+      run: |
+        find include src -name '*.h' -o -name '*.cc' |  xargs clang-format -i -style=file -fallback-style=none
+        git diff --exit-code

.github/workflows/linux.yml

@@ -0,0 +1,111 @@
+name: linux
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    runs-on: ubuntu-20.04
+    strategy:
+      matrix:
+        cxx: [g++-4.8, g++-10, clang++-9]
+        build_type: [Debug, Release]
+        std: [11]
+        include:
+          - cxx: g++-4.8
+            install: sudo apt install g++-4.8
+          - cxx: g++-8
+            build_type: Debug
+            std: 14
+            install: sudo apt install g++-8
+          - cxx: g++-8
+            build_type: Debug
+            std: 17
+            install: sudo apt install g++-8
+          - cxx: g++-9
+            build_type: Debug
+            std: 17
+          - cxx: g++-10
+            build_type: Debug
+            std: 17
+          - cxx: g++-11
+            build_type: Debug
+            std: 20
+            install: sudo apt install g++-11
+          - cxx: clang++-8
+            build_type: Debug
+            std: 17
+            cxxflags: -stdlib=libc++
+            install: sudo apt install clang-8 libc++-8-dev libc++abi-8-dev
+          - cxx: clang++-9
+            install: sudo apt install clang-9
+          - cxx: clang++-9
+            build_type: Debug
+            fuzz: -DFMT_FUZZ=ON -DFMT_FUZZ_LINKMAIN=ON
+            std: 17
+            install: sudo apt install clang-9
+          - cxx: clang++-11
+            build_type: Debug
+            std: 20
+          - cxx: clang++-11
+            build_type: Debug
+            std: 20
+            cxxflags: -stdlib=libc++
+            install: sudo apt install libc++-11-dev libc++abi-11-dev
+          - shared: -DBUILD_SHARED_LIBS=ON
+
+    steps:
+    - uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # v4.1.0
+
+    - name: Set timezone
+      run: sudo timedatectl set-timezone 'Asia/Yekaterinburg'
+
+    - name: Add repositories for older GCC
+      run: |
+        # Below two repos provide GCC 4.8, 5.5 and 6.4
+        sudo apt-add-repository 'deb http://azure.archive.ubuntu.com/ubuntu/ bionic main'
+        sudo apt-add-repository 'deb http://azure.archive.ubuntu.com/ubuntu/ bionic universe'
+        # Below two repos additionally update GCC 6 to 6.5
+        # sudo apt-add-repository 'deb http://azure.archive.ubuntu.com/ubuntu/ bionic-updates main'
+        # sudo apt-add-repository 'deb http://azure.archive.ubuntu.com/ubuntu/ bionic-updates universe'
+      if: ${{ matrix.cxx == 'g++-4.8' }}
+
+    - name: Add ubuntu mirrors
+      run: |
+        # Github Actions caching proxy is at times unreliable
+        # see https://github.com/actions/runner-images/issues/7048
+        printf 'http://azure.archive.ubuntu.com/ubuntu\tpriority:1\n' | sudo tee /etc/apt/mirrors.txt
+        curl http://mirrors.ubuntu.com/mirrors.txt | sudo tee --append /etc/apt/mirrors.txt
+        sudo sed -i 's~http://azure.archive.ubuntu.com/ubuntu/~mirror+file:/etc/apt/mirrors.txt~' /etc/apt/sources.list
+
+    - name: Create Build Environment
+      run: |
+        sudo apt update
+        ${{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 +1,55 @@
+name: macos
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    strategy:
+      matrix:
+        os: [macos-11, macos-13]
+        build_type: [Debug, Release]
+        std: [11, 17, 20]
+        exclude:
+          - { os: macos-11, std: 20 }
+          - { os: macos-13, std: 11 }
+          - { os: macos-13, std: 17 }
+        include:
+          - shared: -DBUILD_SHARED_LIBS=ON
+
+    runs-on: '${{ matrix.os }}'
+
+    steps:
+    - uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # v4.1.0
+
+    - name: Set timezone
+      run: sudo systemsetup -settimezone 'Asia/Yekaterinburg'
+
+    - name: Select Xcode 14.3 (macOS 13)
+      run: sudo xcode-select -s "/Applications/Xcode_14.3.app"
+      if: ${{ matrix.os == 'macos-13' }}
+
+    - 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}} ${{matrix.shared}} \
+              -DCMAKE_CXX_STANDARD=${{matrix.std}} \
+              -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/scorecard.yml

@@ -0,0 +1,65 @@
+# This workflow uses actions that are not certified by GitHub. They are provided
+# by a third-party and are governed by separate terms of service, privacy
+# policy, and support documentation.
+
+name: Scorecard supply-chain security
+on:
+  # For Branch-Protection check. Only the default branch is supported. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#branch-protection
+  branch_protection_rule:
+  # To guarantee Maintained check is occasionally updated. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#maintained
+  schedule:
+    - cron: '26 14 * * 5'
+  push:
+    branches: [ "master" ]
+
+# Declare default permissions as read only.
+permissions: read-all
+
+jobs:
+  analysis:
+    name: Scorecard analysis
+    runs-on: ubuntu-latest
+    permissions:
+      # Needed to upload the results to code-scanning dashboard.
+      security-events: write
+      # Needed to publish results and get a badge (see publish_results below).
+      id-token: write
+
+    steps:
+      - name: "Checkout code"
+        uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # v4.1.0
+        with:
+          persist-credentials: false
+
+      - name: "Run analysis"
+        uses: ossf/scorecard-action@0864cf19026789058feabb7e87baa5f140aac736 # v2.3.1
+        with:
+          results_file: results.sarif
+          results_format: sarif
+          # (Optional) "write" PAT token. Uncomment the `repo_token` line below if:
+          # - you want to enable the Branch-Protection check on a *public* repository, or
+          # To create the PAT, follow the steps in https://github.com/ossf/scorecard-action#authentication-with-pat.
+          # repo_token: ${{ secrets.SCORECARD_TOKEN }}
+
+          # Public repositories:
+          #   - Publish results to OpenSSF REST API for easy access by consumers
+          #   - Allows the repository to include the Scorecard badge.
+          #   - See https://github.com/ossf/scorecard-action#publishing-results.
+          publish_results: true
+
+      # Upload the results as artifacts (optional). Commenting out will disable uploads of run results in SARIF
+      # format to the repository Actions tab.
+      - name: "Upload artifact"
+        uses: actions/upload-artifact@c7d193f32edcb7bfad88892161225aeda64e9392 # v4.0.0
+        with:
+          name: SARIF file
+          path: results.sarif
+          retention-days: 5
+
+      # Upload the results to GitHub's code scanning dashboard.
+      - name: "Upload to code-scanning"
+        uses: github/codeql-action/upload-sarif@74483a38d39275f33fcff5f35b679b5ca4a26a99 # v2.22.5
+        with:
+          sarif_file: results.sarif

.github/workflows/windows.yml

@@ -0,0 +1,100 @@
+name: windows
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    runs-on: ${{matrix.os}}
+    strategy:
+      matrix:
+        # windows-2019 has MSVC 2019 installed;
+        # windows-2022 has MSVC 2022 installed:
+        # https://github.com/actions/virtual-environments.
+        os: [windows-2019]
+        platform: [Win32, x64]
+        toolset: [v140, v141, v142]
+        standard: [14, 17, 20]
+        shared: ["", -DBUILD_SHARED_LIBS=ON]
+        build_type: [Debug, Release]
+        exclude:
+          - { toolset: v140, standard: 17 }
+          - { toolset: v140, standard: 20 }
+          - { toolset: v141, standard: 14 }
+          - { toolset: v141, standard: 20 }
+          - { toolset: v142, standard: 14 }
+          - { platform: Win32, toolset: v140 }
+          - { platform: Win32, toolset: v141 }
+          - { platform: Win32, standard: 14 }
+          - { platform: Win32, standard: 20 }
+          - { platform: x64, toolset: v140, shared: -DBUILD_SHARED_LIBS=ON }
+          - { platform: x64, toolset: v141, shared: -DBUILD_SHARED_LIBS=ON }
+          - { platform: x64, standard: 14, shared: -DBUILD_SHARED_LIBS=ON }
+          - { platform: x64, standard: 20, shared: -DBUILD_SHARED_LIBS=ON }
+        include:
+          - os: windows-2022
+            platform: x64
+            toolset: v143
+            build_type: Debug
+            standard: 20
+
+    steps:
+    - uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # v4.1.0
+
+    - name: Set timezone
+      run: tzutil /s "Ekaterinburg Standard Time"
+
+    - 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 -A ${{matrix.platform}} -T ${{matrix.toolset}} \
+              -DCMAKE_CXX_STANDARD=${{matrix.standard}} \
+              ${{matrix.shared}} -DCMAKE_BUILD_TYPE=${{matrix.build_type}} \
+              $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
+
+  mingw:
+    runs-on: windows-latest
+    defaults:
+      run:
+        shell: msys2 {0}
+    strategy:
+      matrix:
+        sys: [ mingw64, ucrt64 ]
+    steps:
+    - name: Set timezone
+      run: tzutil /s "Ekaterinburg Standard Time"
+      shell: cmd
+    - uses: msys2/setup-msys2@7efe20baefed56359985e327d329042cde2434ff # v2
+      with:
+        release: false
+        msystem: ${{matrix.sys}}
+        pacboy: cc:p cmake:p ninja:p lld:p
+    - uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # v4.1.0
+    - name: Configure
+      run: cmake -B ../build -DBUILD_SHARED_LIBS=ON -DCMAKE_BUILD_TYPE=Debug
+      env: { LDFLAGS: -fuse-ld=lld }
+    - name: Build
+      run: cmake --build ../build
+    - name: Test
+      run: ctest -j `nproc` --test-dir ../build
+      env:
+        CTEST_OUTPUT_ON_FAILURE: True

.gitignore

@@ -1,33 +1,24 @@
-.vscode/
-
-*.iml
-.idea/
-.externalNativeBuild/
-.gradle/
-gradle/
-gradlew*
-local.properties
-build/
-
-bin/
-/_CPack_Packages
-/CMakeScripts
-/doc/doxyxml
-/doc/html
-virtualenv
-/Testing
-/install_manifest.txt
-*~
 *.a
 *.so*
 *.xcodeproj
-*.zip
-cmake_install.cmake
-CPack*.cmake
-fmt-*.cmake
-CTestTestfile.cmake
+*~
+.vscode/
+/CMakeScripts
+/Testing
+/_CPack_Packages
+/doc/doxyxml
+/doc/html
+/doc/node_modules
+/install_manifest.txt
 CMakeCache.txt
 CMakeFiles
+CPack*.cmake
+CTestTestfile.cmake
 FMT.build
 Makefile
-run-msbuild.bat
+bin/
+build/
+cmake_install.cmake
+fmt-*.cmake
+fmt.pc
+virtualenv

.travis.yml

@@ -1,67 +0,0 @@
-language: cpp
-dist: trusty
-sudo: required # the doc target uses sudo to install dependencies
-
-os:
-  - linux
-  - osx
-
-env:
-  global:
-    - secure: |-
-        a1eovNn4uol9won7ghr67eD3/59oeESN+G9bWE+ecI1V6yRseG9whniGhIpC/YfMW/Qz5I
-        5sxSmFjaw9bxCISNwUIrL1O5x2AmRYTnFcXk4dFsUvlZg+WeF/aKyBYCNRM8C2ndbBmtAO
-        o1F2EwFbiso0EmtzhAPs19ujiVxkLn4=
-  matrix:
-    - BUILD=Doc
-    - BUILD=Debug STANDARD=14
-    - BUILD=Release STANDARD=14
-
-matrix:
-  exclude:
-    - os: osx
-      env: BUILD=Doc
-  include:
-    - language: android
-      android:
-      components:
-        - tools
-        - platform-tools
-        - android-21
-        - sys-img-armeabi-v7a-android-21
-      env:
-        - ANDROID=true
-      before_install:
-        - git submodule update --init --recursive
-        - sudo apt-get install wget unzip tree
-      install:
-        # Accept SDK Licenses + Install NDK
-        - yes | sdkmanager --update > /dev/null 2>&1
-        - sdkmanager ndk-bundle > /dev/null 2>&1
-        # Download Gradle 4.3.1 
-        - wget https://services.gradle.org/distributions/gradle-4.3.1-bin.zip
-        - mkdir -p gradle
-        - unzip -q -d ./gradle gradle-4.3.1-bin.zip
-        - export GRADLE=${TRAVIS_BUILD_DIR}/gradle/gradle-4.3.1/bin/gradle
-      before_script:
-        - bash $GRADLE --version
-        - cd ./support
-      script:
-        - bash $GRADLE clean assemble
-      after_success:
-        - cd ${TRAVIS_BUILD_DIR}
-        - tree ./libs
-
-# Install gcc-6 for extended constexpr support.
-addons:
-  apt:
-    sources:
-    - ubuntu-toolchain-r-test
-    packages:
-    - g++-6
-
-before_install:
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then export CXX=g++-6; fi
-
-script:
-  - support/travis-build.py

CMakeLists.txt

@@ -1,41 +1,171 @@
-message(STATUS "CMake version: ${CMAKE_VERSION}")
+cmake_minimum_required(VERSION 3.8...3.26)
 
-cmake_minimum_required(VERSION 2.8.12)
+# 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})
+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)
+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()
 
+# DEPRECATED! Should be merged into add_module_library.
+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})
+    set_target_properties(${target} PROPERTIES ADDITIONAL_CLEAN_FILES ${BMI})
+    set_source_files_properties(${BMI} PROPERTIES GENERATED ON)
+  endif ()
+endfunction()
+
+# Adds a library compiled with C++20 module support.
+# `enabled` is a CMake variables that specifies if modules are enabled.
+# If modules are disabled `add_module_library` falls back to creating a
+# non-modular library.
+#
+# Usage:
+#   add_module_library(<name> [sources...] FALLBACK [sources...] [IF enabled])
+function(add_module_library name)
+  cmake_parse_arguments(AML "" "IF" "FALLBACK" ${ARGN})
+  set(sources ${AML_UNPARSED_ARGUMENTS})
+
+  add_library(${name})
+  set_target_properties(${name} PROPERTIES LINKER_LANGUAGE CXX)
+
+  if (NOT ${${AML_IF}})
+    # Create a non-modular library.
+    target_sources(${name} PRIVATE ${AML_FALLBACK})
+    return()
+  endif ()
+
+  # Modules require C++20.
+  target_compile_features(${name} PUBLIC cxx_std_20)
+  if (CMAKE_COMPILER_IS_GNUCXX)
+    target_compile_options(${name} PUBLIC -fmodules-ts)
+  endif ()
+
+  # `std` is affected by CMake options and may be higher than C++20.
+  get_target_property(std ${name} CXX_STANDARD)
+
+  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+    set(pcms)
+    foreach (src ${sources})
+      get_filename_component(pcm ${src} NAME_WE)
+      set(pcm ${pcm}.pcm)
+
+      # Propagate -fmodule-file=*.pcm to targets that link with this library.
+      target_compile_options(
+        ${name} PUBLIC -fmodule-file=${CMAKE_CURRENT_BINARY_DIR}/${pcm})
+
+      # Use an absolute path to prevent target_link_libraries prepending -l
+      # to it.
+      set(pcms ${pcms} ${CMAKE_CURRENT_BINARY_DIR}/${pcm})
+      add_custom_command(
+        OUTPUT ${pcm}
+        COMMAND ${CMAKE_CXX_COMPILER}
+                -std=c++${std} -x c++-module --precompile -c
+                -o ${pcm} ${CMAKE_CURRENT_SOURCE_DIR}/${src}
+                "-I$<JOIN:$<TARGET_PROPERTY:${name},INCLUDE_DIRECTORIES>,;-I>"
+        # Required by the -I generator expression above.
+        COMMAND_EXPAND_LISTS
+        DEPENDS ${src})
+    endforeach ()
+
+    # Add .pcm files as sources to make sure they are built before the library.
+    set(sources)
+    foreach (pcm ${pcms})
+      get_filename_component(pcm_we ${pcm} NAME_WE)
+      set(obj ${pcm_we}.o)
+      # Use an absolute path to prevent target_link_libraries prepending -l.
+      set(sources ${sources} ${pcm} ${CMAKE_CURRENT_BINARY_DIR}/${obj})
+      add_custom_command(
+        OUTPUT ${obj}
+        COMMAND ${CMAKE_CXX_COMPILER} $<TARGET_PROPERTY:${name},COMPILE_OPTIONS>
+                -c -o ${obj} ${pcm}
+        DEPENDS ${pcm})
+    endforeach ()
+  endif ()
+  target_sources(${name} PRIVATE ${sources})
+endfunction()
+
+include(CMakeParseArguments)
+
+# Sets a cache variable with a docstring joined from multiple arguments:
+#   set(<variable> <value>... CACHE <type> <docstring>...)
+# This allows splitting a long docstring for readability.
+function(set_verbose)
+  # cmake_parse_arguments is broken in CMake 3.4 (cannot parse CACHE) so use
+  # list instead.
+  list(GET ARGN 0 var)
+  list(REMOVE_AT ARGN 0)
+  list(GET ARGN 0 val)
+  list(REMOVE_AT ARGN 0)
+  list(REMOVE_AT ARGN 0)
+  list(GET ARGN 0 type)
+  list(REMOVE_AT ARGN 0)
+  join(doc ${ARGN})
+  set(${var} ${val} CACHE ${type} ${doc})
+endfunction()
+
 # Set the default CMAKE_BUILD_TYPE to Release.
 # This should be done before the project command since the latter can set
 # CMAKE_BUILD_TYPE itself (it does so for nmake).
-if (NOT CMAKE_BUILD_TYPE)
-  join(doc "Choose the type of build, options are: None(CMAKE_CXX_FLAGS or "
-           "CMAKE_C_FLAGS used) Debug Release RelWithDebInfo MinSizeRel.")
-  set(CMAKE_BUILD_TYPE Release CACHE STRING ${doc})
+if (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.")
 endif ()
 
+project(FMT CXX)
+include(GNUInstallDirs)
+set_verbose(FMT_INC_DIR ${CMAKE_INSTALL_INCLUDEDIR} CACHE STRING
+            "Installation directory for include files, a relative path that "
+            "will be joined with ${CMAKE_INSTALL_PREFIX} or an absolute path.")
+
 option(FMT_PEDANTIC "Enable extra warnings and expensive tests." OFF)
+option(FMT_WERROR "Halt the compilation with an error on compiler warnings."
+       OFF)
 
 # 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_USE_CPP14 "Enable the addition of C++14 compiler flags." ON)
+option(FMT_DOC "Generate the doc target." ${FMT_MASTER_PROJECT})
+option(FMT_INSTALL "Generate the install target." ON)
+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)
 
-project(FMT)
+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 ()
+if (CMAKE_SYSTEM_NAME STREQUAL "MSDOS")
+  set(FMT_TEST OFF)
+  message(STATUS "MSDOS is incompatible with gtest")
+endif ()
 
 # Get version from core.h
 file(READ include/fmt/core.h core_h)
@@ -52,18 +182,72 @@ message(STATUS "Version: ${FMT_VERSION}")
 
 message(STATUS "Build type: ${CMAKE_BUILD_TYPE}")
 
-set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
+if (NOT CMAKE_RUNTIME_OUTPUT_DIRECTORY)
+  set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/bin)
+endif ()
 
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH}
   "${CMAKE_CURRENT_SOURCE_DIR}/support/cmake")
 
-include(cxx14)
+include(CheckCXXCompilerFlag)
+include(JoinPaths)
 
-if (CMAKE_COMPILER_IS_GNUCXX OR (CMAKE_CXX_COMPILER_ID MATCHES "Clang"))
-  set(PEDANTIC_COMPILE_FLAGS -Wall -Wextra -Wshadow -pedantic)
+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 (MASTER_PROJECT AND CMAKE_GENERATOR MATCHES "Visual Studio")
+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
+      -Wctor-dtor-privacy -Wdisabled-optimization
+      -Winvalid-pch -Woverloaded-virtual
+      -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}
+         -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 -Wshadow)
+  endif ()
+  if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 6.0)
+      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wshift-overflow=2
+          -Wnull-dereference -Wduplicated-cond)
+  endif ()
+  set(WERROR_FLAG -Werror)
+endif ()
+
+if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+  set(PEDANTIC_COMPILE_FLAGS -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 ${PEDANTIC_COMPILE_FLAGS}
+        -Wzero-as-null-pointer-constant)
+  endif ()
+  set(WERROR_FLAG -Werror)
+endif ()
+
+if (MSVC)
+  set(PEDANTIC_COMPILE_FLAGS /W3)
+  set(WERROR_FLAG /WX)
+endif ()
+
+if (FMT_MASTER_PROJECT AND CMAKE_GENERATOR MATCHES "Visual Studio")
   # If Microsoft SDK is installed create script run-msbuild.bat that
   # calls SetEnv.cmd to set up build environment and runs msbuild.
   # It is useful when building Visual Studio projects with the SDK
@@ -73,19 +257,14 @@ if (MASTER_PROJECT AND CMAKE_GENERATOR MATCHES "Visual Studio")
     set(MSBUILD_SETUP "call \"${WINSDK_SETENV}\"")
   endif ()
   # Set FrameworkPathOverride to get rid of MSB3644 warnings.
-  set(netfxpath "C:\\Program Files\\Reference Assemblies\\Microsoft\\Framework\\.NETFramework\\v4.0")
+  join(netfxpath
+       "C:\\Program Files\\Reference Assemblies\\Microsoft\\Framework\\"
+       ".NETFramework\\v4.0")
   file(WRITE run-msbuild.bat "
     ${MSBUILD_SETUP}
     ${CMAKE_MAKE_PROGRAM} -p:FrameworkPathOverride=\"${netfxpath}\" %*")
 endif ()
 
-include(CheckSymbolExists)
-if (WIN32)
-  check_symbol_exists(open io.h HAVE_OPEN)
-else ()
-  check_symbol_exists(open fcntl.h HAVE_OPEN)
-endif ()
-
 function(add_headers VAR)
   set(headers ${${VAR}})
   foreach (header ${ARGN})
@@ -95,83 +274,127 @@ function(add_headers VAR)
 endfunction()
 
 # Define the fmt library, its includes and the needed defines.
-add_headers(FMT_HEADERS core.h format.h format-inl.h ostream.h printf.h time.h
-                        ranges.h)
+add_headers(FMT_HEADERS args.h chrono.h color.h compile.h core.h format.h
+                        format-inl.h os.h ostream.h printf.h ranges.h std.h
+                        xchar.h)
 set(FMT_SOURCES src/format.cc)
-if (HAVE_OPEN)
-  add_headers(FMT_HEADERS posix.h)
-  set(FMT_SOURCES ${FMT_SOURCES} src/posix.cc)
+if (FMT_OS)
+  set(FMT_SOURCES ${FMT_SOURCES} src/os.cc)
 endif ()
 
-add_library(fmt ${FMT_SOURCES} ${FMT_HEADERS} README.rst ChangeLog.rst)
+add_module_library(fmt src/fmt.cc FALLBACK
+                   ${FMT_SOURCES} ${FMT_HEADERS} README.md ChangeLog.md
+                   IF FMT_MODULE)
 add_library(fmt::fmt ALIAS fmt)
+if (FMT_MODULE)
+  enable_module(fmt)
+endif ()
 
-# Starting with CMake 3.1 the CXX_STANDARD property can be used instead.
-# Don't export -std since it may break projects that use other standards.
-target_compile_options(fmt PRIVATE ${CPP14_FLAG})
+if (FMT_WERROR)
+  target_compile_options(fmt PRIVATE ${WERROR_FLAG})
+endif ()
 if (FMT_PEDANTIC)
   target_compile_options(fmt PRIVATE ${PEDANTIC_COMPILE_FLAGS})
 endif ()
 
-target_include_directories(fmt PUBLIC
+if (cxx_std_11 IN_LIST CMAKE_CXX_COMPILE_FEATURES)
+  target_compile_features(fmt PUBLIC cxx_std_11)
+else ()
+  message(WARNING "Feature cxx_std_11 is unknown for the CXX compiler")
+endif ()
+
+target_include_directories(fmt ${FMT_SYSTEM_HEADERS_ATTRIBUTE} PUBLIC
   $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
-  $<INSTALL_INTERFACE:include>)
+  $<INSTALL_INTERFACE:${FMT_INC_DIR}>)
+
+set(FMT_DEBUG_POSTFIX d CACHE STRING "Debug library postfix.")
 
 set_target_properties(fmt PROPERTIES
   VERSION ${FMT_VERSION} SOVERSION ${CPACK_PACKAGE_VERSION_MAJOR}
-  DEBUG_POSTFIX d)
+  PUBLIC_HEADER "${FMT_HEADERS}"
+  DEBUG_POSTFIX "${FMT_DEBUG_POSTFIX}"
+
+  # Workaround for Visual Studio 2017:
+  # Ensure the .pdb is created with the same name and in the same directory
+  # as the .lib. Newer VS versions already do this by default, but there is no
+  # harm in setting it for those too. Ignored by other generators.
+  COMPILE_PDB_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}"
+  COMPILE_PDB_NAME "fmt"
+  COMPILE_PDB_NAME_DEBUG "fmt${FMT_DEBUG_POSTFIX}")
+
+# Set FMT_LIB_NAME for pkg-config fmt.pc. We cannot use the OUTPUT_NAME target
+# property because it's not set by default.
+set(FMT_LIB_NAME fmt)
+if (CMAKE_BUILD_TYPE STREQUAL "Debug")
+  set(FMT_LIB_NAME ${FMT_LIB_NAME}${FMT_DEBUG_POSTFIX})
+endif ()
 
 if (BUILD_SHARED_LIBS)
-  if (UNIX AND NOT APPLE)
-    # Fix rpmlint warning:
-    # unused-direct-shlib-dependency /usr/lib/libformat.so.1.1.0 /lib/libm.so.6.
-    target_link_libraries(fmt -Wl,--as-needed)
-  endif ()
-  target_compile_definitions(fmt PRIVATE FMT_EXPORT INTERFACE FMT_SHARED)
+  target_compile_definitions(fmt PRIVATE FMT_LIB_EXPORT INTERFACE FMT_SHARED)
+endif ()
+if (FMT_SAFE_DURATION_CAST)
+  target_compile_definitions(fmt PUBLIC FMT_SAFE_DURATION_CAST)
 endif ()
 
-# Additionally define a header-only library when CMake is new enough.
-if (CMAKE_VERSION VERSION_GREATER 3.1.0 OR CMAKE_VERSION VERSION_EQUAL 3.1.0)
-  add_library(fmt-header-only INTERFACE)
-  add_library(fmt::fmt-header-only ALIAS fmt-header-only)
+add_library(fmt-header-only INTERFACE)
+add_library(fmt::fmt-header-only ALIAS fmt-header-only)
 
-  target_compile_definitions(fmt-header-only INTERFACE FMT_HEADER_ONLY=1)
+target_compile_definitions(fmt-header-only INTERFACE FMT_HEADER_ONLY=1)
+target_compile_features(fmt-header-only INTERFACE cxx_std_11)
 
-  target_include_directories(fmt-header-only INTERFACE
-    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
-    $<INSTALL_INTERFACE:include>)
-endif ()
+target_include_directories(fmt-header-only
+  ${FMT_SYSTEM_HEADERS_ATTRIBUTE} INTERFACE
+  $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
+  $<INSTALL_INTERFACE:${FMT_INC_DIR}>)
 
 # Install targets.
 if (FMT_INSTALL)
-  include(GNUInstallDirs)
   include(CMakePackageConfigHelpers)
-  set(FMT_CMAKE_DIR ${CMAKE_INSTALL_LIBDIR}/cmake/fmt CACHE STRING
-    "Installation directory for cmake files, relative to ${CMAKE_INSTALL_PREFIX}.")
+  set_verbose(FMT_CMAKE_DIR ${CMAKE_INSTALL_LIBDIR}/cmake/fmt CACHE STRING
+              "Installation directory for cmake files, a relative path that "
+              "will be joined with ${CMAKE_INSTALL_PREFIX} or an absolute "
+              "path.")
   set(version_config ${PROJECT_BINARY_DIR}/fmt-config-version.cmake)
   set(project_config ${PROJECT_BINARY_DIR}/fmt-config.cmake)
+  set(pkgconfig ${PROJECT_BINARY_DIR}/fmt.pc)
   set(targets_export_name fmt-targets)
 
-  set (INSTALL_TARGETS fmt)
-  if (TARGET fmt-header-only)
-    set(INSTALL_TARGETS ${INSTALL_TARGETS} fmt-header-only)
-  endif ()
+  set_verbose(FMT_LIB_DIR ${CMAKE_INSTALL_LIBDIR} CACHE STRING
+              "Installation directory for libraries, a relative path that "
+              "will be joined to ${CMAKE_INSTALL_PREFIX} or an absolute path.")
 
-  set(FMT_LIB_DIR ${CMAKE_INSTALL_LIBDIR} CACHE STRING
-      "Installation directory for libraries, relative to ${CMAKE_INSTALL_PREFIX}.")
-
-  set(FMT_INC_DIR ${CMAKE_INSTALL_INCLUDEDIR}/fmt CACHE STRING
-      "Installation directory for include files, relative to ${CMAKE_INSTALL_PREFIX}.")
+  set_verbose(FMT_PKGCONFIG_DIR ${CMAKE_INSTALL_LIBDIR}/pkgconfig CACHE STRING
+              "Installation directory for pkgconfig (.pc) files, a relative "
+              "path that will be joined with ${CMAKE_INSTALL_PREFIX} or an "
+              "absolute path.")
 
   # Generate the version, config and target files into the build directory.
   write_basic_package_version_file(
     ${version_config}
     VERSION ${FMT_VERSION}
     COMPATIBILITY AnyNewerVersion)
+
+  join_paths(libdir_for_pc_file "\${exec_prefix}" "${FMT_LIB_DIR}")
+  join_paths(includedir_for_pc_file "\${prefix}" "${FMT_INC_DIR}")
+
+  configure_file(
+    "${PROJECT_SOURCE_DIR}/support/cmake/fmt.pc.in"
+    "${pkgconfig}"
+    @ONLY)
   configure_package_config_file(
     ${PROJECT_SOURCE_DIR}/support/cmake/fmt-config.cmake.in
     ${project_config}
     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 ${FMT_LIB_DIR}
+          PUBLIC_HEADER DESTINATION "${FMT_INC_DIR}/fmt"
+          RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+
   # Use a namespace because CMake provides better diagnostics for namespaced
   # imported targets.
   export(TARGETS ${INSTALL_TARGETS} NAMESPACE fmt::
@@ -184,10 +407,7 @@ 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}
-          DESTINATION ${FMT_LIB_DIR})
-  install(FILES ${FMT_HEADERS} DESTINATION ${FMT_INC_DIR})
+  install(FILES "${pkgconfig}" DESTINATION "${FMT_PKGCONFIG_DIR}")
 endif ()
 
 if (FMT_DOC)
@@ -199,11 +419,23 @@ if (FMT_TEST)
   add_subdirectory(test)
 endif ()
 
+# Control fuzzing independent of the unit tests.
+if (FMT_FUZZ)
+  add_subdirectory(test/fuzzing)
+
+  # The FMT_FUZZ macro is used to prevent resource exhaustion in fuzzing
+  # mode and make fuzzing practically possible. It is similar to
+  # FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION but uses a different name to
+  # avoid interfering with fuzzing of projects that use {fmt}.
+  # See also https://llvm.org/docs/LibFuzzer.html#fuzzer-friendly-build-mode.
+  target_compile_definitions(fmt PUBLIC FMT_FUZZ)
+endif ()
+
 set(gitignore ${PROJECT_SOURCE_DIR}/.gitignore)
-if (MASTER_PROJECT AND EXISTS ${gitignore})
+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)
+  list(REMOVE_ITEM lines /doc/html)
   foreach (line ${lines})
     string(REPLACE "." "[.]" line "${line}")
     string(REPLACE "*" ".*" line "${line}")
@@ -216,6 +448,6 @@ if (MASTER_PROJECT AND EXISTS ${gitignore})
   set(CPACK_SOURCE_IGNORE_FILES ${ignored_files})
   set(CPACK_SOURCE_PACKAGE_FILE_NAME fmt-${FMT_VERSION})
   set(CPACK_PACKAGE_NAME fmt)
-  set(CPACK_RESOURCE_FILE_README ${PROJECT_SOURCE_DIR}/README.rst)
+  set(CPACK_RESOURCE_FILE_README ${PROJECT_SOURCE_DIR}/README.md)
   include(CPack)
 endif ()

CONTRIBUTING.md

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

CONTRIBUTING.rst

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

LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2012 - present, Victor Zverovich and {fmt} contributors
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+--- Optional exception to the license ---
+
+As an exception, if, as a result of your compiling your source code, portions
+of this Software are embedded into a machine-executable object form of such
+source code, you may redistribute such embedded portions in such object form
+without including the above copyright and permission notices.

LICENSE.rst

@@ -1,23 +0,0 @@
-Copyright (c) 2012 - 2016, Victor Zverovich
-
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are met:
-
-1. Redistributions of source code must retain the above copyright notice, this
-   list of conditions and the following disclaimer.
-2. Redistributions in binary form must reproduce the above copyright notice,
-   this list of conditions and the following disclaimer in the documentation
-   and/or other materials provided with the distribution.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
-ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
-DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
-ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
-(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
-LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
-ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
-SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

README.md

@@ -0,0 +1,490 @@
+<img src="https://user-images.githubusercontent.com/576385/156254208-f5b743a9-88cf-439d-b0c0-923d53e8d551.png" alt="{fmt}" width="25%"/>
+
+[![image](https://github.com/fmtlib/fmt/workflows/linux/badge.svg)](https://github.com/fmtlib/fmt/actions?query=workflow%3Alinux)
+[![image](https://github.com/fmtlib/fmt/workflows/macos/badge.svg)](https://github.com/fmtlib/fmt/actions?query=workflow%3Amacos)
+[![image](https://github.com/fmtlib/fmt/workflows/windows/badge.svg)](https://github.com/fmtlib/fmt/actions?query=workflow%3Awindows)
+[![fmt is continuously fuzzed at oss-fuzz](https://oss-fuzz-build-logs.storage.googleapis.com/badges/fmt.svg)](https://bugs.chromium.org/p/oss-fuzz/issues/list?\%0Acolspec=ID%20Type%20Component%20Status%20Proj%20Reported%20Owner%20\%0ASummary&q=proj%3Dfmt&can=1)
+[![Ask questions at StackOverflow with the tag fmt](https://img.shields.io/badge/stackoverflow-fmt-blue.svg)](https://stackoverflow.com/questions/tagged/fmt)
+[![image](https://api.securityscorecards.dev/projects/github.com/fmtlib/fmt/badge)](https://securityscorecards.dev/viewer/?uri=github.com/fmtlib/fmt)
+
+**{fmt}** is an open-source formatting library providing a fast and safe
+alternative to C stdio and C++ iostreams.
+
+If you like this project, please consider donating to one of the funds
+that help victims of the war in Ukraine: <https://www.stopputin.net/>.
+
+[Documentation](https://fmt.dev)
+
+[Cheat Sheets](https://hackingcpp.com/cpp/libs/fmt.html)
+
+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/latest/api.html) with positional
+  arguments for localization
+- Implementation of [C++20
+  std::format](https://en.cppreference.com/w/cpp/utility/format) and
+  [C++23 std::print](https://en.cppreference.com/w/cpp/io/print)
+- [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 using the
+  [Dragonbox](https://github.com/jk-jeon/dragonbox) algorithm
+- Portable Unicode support
+- 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#formatting-user-defined-types)
+- High performance: faster than common standard library
+  implementations of `(s)printf`, iostreams, `to_string` and
+  `to_chars`, see [Speed tests](#speed-tests) and [Converting a
+  hundred million integers to strings per
+  second](http://www.zverovich.net/2020/06/13/fast-int-to-string-revisited.html)
+- Small code size both in terms of source code with the minimum
+  configuration consisting of just three files, `core.h`, `format.h`
+  and `format-inl.h`, and compiled code; see [Compile time and code
+  bloat](#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%20Component%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
+- Ease of use: small self-contained code base, no external
+  dependencies, permissive MIT
+  [license](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 such as
+  `-Wall -Wextra -pedantic`
+- Locale independence by default
+- Optional header-only configuration enabled with the
+  `FMT_HEADER_ONLY` macro
+
+See the [documentation](https://fmt.dev) for more details.
+
+# Examples
+
+**Print to stdout** ([run](https://godbolt.org/z/Tevcjh))
+
+``` c++
+#include <fmt/core.h>
+
+int main() {
+  fmt::print("Hello, world!\n");
+}
+```
+
+**Format a string** ([run](https://godbolt.org/z/oK8h33))
+
+``` c++
+std::string s = fmt::format("The answer is {}.", 42);
+// s == "The answer is 42."
+```
+
+**Format a string using positional arguments**
+([run](https://godbolt.org/z/Yn7Txe))
+
+``` c++
+std::string s = fmt::format("I'd rather be {1} than {0}.", "right", "happy");
+// s == "I'd rather be happy than right."
+```
+
+**Print dates and times** ([run](https://godbolt.org/z/c31ExdY3W))
+
+``` c++
+#include <fmt/chrono.h>
+
+int main() {
+  auto now = std::chrono::system_clock::now();
+  fmt::print("Date and time: {}\n", now);
+  fmt::print("Time: {:%H:%M}\n", now);
+}
+```
+
+Output:
+
+    Date and time: 2023-12-26 19:10:31.557195597
+    Time: 19:10
+
+**Print a container** ([run](https://godbolt.org/z/MxM1YqjE7))
+
+``` c++
+#include <vector>
+#include <fmt/ranges.h>
+
+int main() {
+  std::vector<int> v = {1, 2, 3};
+  fmt::print("{}\n", v);
+}
+```
+
+Output:
+
+    [1, 2, 3]
+
+**Check a format string at compile time**
+
+``` 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**
+
+``` 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**
+
+``` 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, "Olá, {}!\n", "Mundo");
+  fmt::print(fg(fmt::color::steel_blue) | fmt::emphasis::italic,
+             "你好{}！\n", "世界");
+}
+```
+
+Output on a modern terminal with Unicode support:
+
+![image](https://github.com/fmtlib/fmt/assets/%0A576385/2a93c904-d6fa-4aa6-b453-2618e1c327d7)
+
+# Benchmarks
+
+## Speed tests
+
+| Library           | Method        | Run Time, s |
+|-------------------|---------------|-------------|
+| libc              | printf        |   0.91      |
+| libc++            | std::ostream  |   2.49      |
+| {fmt} 9.1         | fmt::print    |   0.74      |
+| Boost Format 1.80 | boost::format |   6.26      |
+| Folly Format      | folly::format |   1.87      |
+
+{fmt} is the fastest of the benchmarked methods, \~20% faster than
+`printf`.
+
+The above results were generated by building `tinyformat_test.cpp` on
+macOS 12.6.1 with `clang++ -O3 -DNDEBUG -DSPEED_TEST -DHAVE_FORMAT`, and
+taking the best of three runs. In the test, the format string
+`"%0.10f:%04d:%+g:%s:%p:%c:%%\n"` or equivalent is filled 2,000,000
+times with output sent to `/dev/null`; for further details refer to the
+[source](https://github.com/fmtlib/format-benchmark/blob/master/src/tinyformat-test.cc).
+
+{fmt} is up to 20-30x faster than `std::ostringstream` and `sprintf` on
+IEEE754 `float` and `double` formatting
+([dtoa-benchmark](https://github.com/fmtlib/dtoa-benchmark)) and faster
+than [double-conversion](https://github.com/google/double-conversion)
+and [ryu](https://github.com/ulfjack/ryu):
+
+[![image](https://user-images.githubusercontent.com/576385/95684665-11719600-0ba8-11eb-8e5b-972ff4e49428.png)](https://fmt.dev/unknown_mac64_clang12.0.html)
+
+## Compile time and code bloat
+
+The script
+[bloat-test.py](https://github.com/fmtlib/format-benchmark/blob/master/bloat-test.py)
+from [format-benchmark](https://github.com/fmtlib/format-benchmark)
+tests compile time and code bloat for nontrivial projects. It generates
+100 translation units and uses `printf()` or its alternative five times
+in each to simulate a medium-sized project. The resulting executable
+size and compile time (Apple LLVM version 8.1.0 (clang-802.0.42), macOS
+Sierra, best of three) is shown in the following tables.
+
+**Optimized build (-O3)**
+
+| Method        | Compile Time, s | Executable size, KiB | Stripped size, KiB |
+|---------------|-----------------|----------------------|--------------------|
+| printf        |   2.6           |   29                 |   26               |
+| printf+string |   16.4          |   29                 |   26               |
+| iostreams     |   31.1          |   59                 |   55               |
+| {fmt}         |   19.0          |   37                 |   34               |
+| Boost Format  |   91.9          |   226                |   203              |
+| Folly Format  |   115.7         |   101                |   88               |
+
+As you can see, {fmt} has 60% less overhead in terms of resulting binary
+code size compared to iostreams and comes pretty close to `printf`.
+Boost Format and Folly Format have the largest overheads.
+
+`printf+string` is the same as `printf` but with an extra `<string>`
+include to measure the overhead of the latter.
+
+**Non-optimized build**
+
+| Method        | Compile Time, s | Executable size, KiB | Stripped size, KiB |
+|---------------|-----------------|----------------------|--------------------|
+| printf        |   2.2           |   33                 |   30               |
+| printf+string |   16.0          |   33                 |   30               |
+| iostreams     |   28.3          |   56                 |   52               |
+| {fmt}         |   18.2          |   59                 |   50               |
+| Boost Format  |   54.1          |   365                |   303              |
+| Folly Format  |   79.9          |   445                |   430              |
+
+`libc`, `lib(std)c++`, and `libfmt` are all linked as shared libraries
+to compare formatting function overhead only. Boost Format is a
+header-only library so it doesn\'t provide any linkage options.
+
+## Running the tests
+
+Please refer to [Building the
+library](https://fmt.dev/latest/usage.html#building-the-library) for
+instructions on how to build the library and run the unit tests.
+
+Benchmarks reside in a separate repository,
+[format-benchmarks](https://github.com/fmtlib/format-benchmark), so to
+run the benchmarks you first need to clone this repository and generate
+Makefiles with CMake:
+
+    $ git clone --recursive https://github.com/fmtlib/format-benchmark.git
+    $ cd format-benchmark
+    $ cmake .
+
+Then you can run the speed test:
+
+    $ make speed-test
+
+or the bloat test:
+
+    $ make bloat-test
+
+# Migrating code
+
+[clang-tidy](https://clang.llvm.org/extra/clang-tidy/) v17 (not yet
+released) provides the
+[modernize-use-std-print](https://clang.llvm.org/extra/clang-tidy/checks/modernize/use-std-print.html)
+check that is capable of converting occurrences of `printf` and
+`fprintf` to `fmt::print` if configured to do so. (By default it
+converts to `std::print`.)
+
+# Notable projects using this library
+
+- [0 A.D.](https://play0ad.com/): a free, open-source, cross-platform
+  real-time strategy game
+- [AMPL/MP](https://github.com/ampl/mp): an open-source library for
+  mathematical programming
+- [Apple's FoundationDB](https://github.com/apple/foundationdb): an open-source,
+  distributed, transactional key-value store
+- [Aseprite](https://github.com/aseprite/aseprite): animated sprite
+  editor & pixel art tool
+- [AvioBook](https://www.aviobook.aero/en): a comprehensive aircraft
+  operations suite
+- [Blizzard Battle.net](https://battle.net/): an online gaming
+  platform
+- [Celestia](https://celestia.space/): real-time 3D visualization of
+  space
+- [Ceph](https://ceph.com/): a scalable distributed storage system
+- [ccache](https://ccache.dev/): a compiler cache
+- [ClickHouse](https://github.com/ClickHouse/ClickHouse): an
+  analytical database management system
+- [Contour](https://github.com/contour-terminal/contour/): a modern
+  terminal emulator
+- [CUAUV](https://cuauv.org/): Cornell University\'s autonomous
+  underwater vehicle
+- [Drake](https://drake.mit.edu/): a planning, control, and analysis
+  toolbox for nonlinear dynamical systems (MIT)
+- [Envoy](https://lyft.github.io/envoy/): C++ L7 proxy and
+  communication bus (Lyft)
+- [FiveM](https://fivem.net/): a modification framework for GTA V
+- [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
+- [GemRB](https://gemrb.org/): a portable open-source implementation
+  of Bioware's Infinity Engine
+- [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://github.com/kbengine/kbengine): an open-source
+  MMOG server engine
+- [Keypirinha](https://keypirinha.com/): a semantic launcher for
+  Windows
+- [Kodi](https://kodi.tv/) (formerly xbmc): home theater software
+- [Knuth](https://kth.cash/): high-performance Bitcoin full-node
+- [libunicode](https://github.com/contour-terminal/libunicode/): a
+  modern C++17 Unicode library
+- [MariaDB](https://mariadb.org/): relational database management
+  system
+- [Microsoft Verona](https://github.com/microsoft/verona): research
+  programming language for concurrent ownership
+- [MongoDB](https://mongodb.com/): distributed document database
+- [MongoDB Smasher](https://github.com/duckie/mongo_smasher): a small
+  tool to generate randomized datasets
+- [OpenSpace](https://openspaceproject.com/): an open-source
+  astrovisualization framework
+- [PenUltima Online (POL)](https://www.polserver.com/): an MMO server,
+  compatible with most Ultima Online clients
+- [PyTorch](https://github.com/pytorch/pytorch): an open-source
+  machine learning library
+- [quasardb](https://www.quasardb.net/): a distributed,
+  high-performance, associative database
+- [Quill](https://github.com/odygrd/quill): asynchronous low-latency
+  logging library
+- [QKW](https://github.com/ravijanjam/qkw): generalizing aliasing to
+  simplify navigation, and executing complex multi-line terminal
+  command sequences
+- [redis-cerberus](https://github.com/HunanTV/redis-cerberus): a Redis
+  cluster proxy
+- [redpanda](https://vectorized.io/redpanda): a 10x faster Kafka®
+  replacement for mission-critical systems written in C++
+- [rpclib](http://rpclib.net/): a modern C++ msgpack-RPC server and
+  client library
+- [Salesforce Analytics
+  Cloud](https://www.salesforce.com/analytics-cloud/overview/):
+  business intelligence software
+- [Scylla](https://www.scylladb.com/): a Cassandra-compatible NoSQL
+  data store that can handle 1 million transactions per second on a
+  single server
+- [Seastar](http://www.seastar-project.org/): an advanced, open-source
+  C++ framework for high-performance server applications on modern
+  hardware
+- [spdlog](https://github.com/gabime/spdlog): super fast C++ logging
+  library
+- [Stellar](https://www.stellar.org/): financial platform
+- [Touch Surgery](https://www.touchsurgery.com/): surgery simulator
+- [TrinityCore](https://github.com/TrinityCore/TrinityCore):
+  open-source MMORPG framework
+- [🐙 userver framework](https://userver.tech/): open-source
+  asynchronous framework with a rich set of abstractions and database
+  drivers
+- [Windows Terminal](https://github.com/microsoft/terminal): the new
+  Windows terminal
+
+[More\...](https://github.com/search?q=fmtlib&type=Code)
+
+If you are aware of other projects using this library, please let me
+know by [email](mailto:victor.zverovich@gmail.com) or by submitting an
+[issue](https://github.com/fmtlib/fmt/issues).
+
+# Motivation
+
+So why yet another formatting library?
+
+There are plenty of methods for doing this task, from standard ones like
+the printf family of function and iostreams to Boost Format and
+FastFormat libraries. The reason for creating a new library is that
+every existing solution that I found either had serious issues or
+didn\'t provide all the features I needed.
+
+## printf
+
+The good thing about `printf` is that it is pretty fast and readily
+available being a part of the C standard library. The main drawback is
+that it doesn\'t support user-defined types. `printf` also has safety
+issues although they are somewhat mitigated with [\_\_attribute\_\_
+((format (printf,
+\...))](https://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html) in
+GCC. There is a POSIX extension that adds positional arguments required
+for
+[i18n](https://en.wikipedia.org/wiki/Internationalization_and_localization)
+to `printf` but it is not a part of C99 and may not be available on some
+platforms.
+
+## iostreams
+
+The main issue with iostreams is best illustrated with an example:
+
+``` c++
+std::cout << std::setprecision(2) << std::fixed << 1.23456 << "\n";
+```
+
+which is a lot of typing compared to printf:
+
+``` c++
+printf("%.2f\n", 1.23456);
+```
+
+Matthew Wilson, the author of FastFormat, called this \"chevron hell\".
+iostreams don\'t support positional arguments by design.
+
+The good part is that iostreams support user-defined types and are safe
+although error handling is awkward.
+
+## Boost Format
+
+This is a very powerful library that supports both `printf`-like format
+strings and positional arguments. Its main drawback is performance.
+According to various benchmarks, it is much slower than other methods
+considered here. Boost Format also has excessive build times and severe
+code bloat issues (see [Benchmarks](#benchmarks)).
+
+## FastFormat
+
+This is an interesting library that is fast, safe, and has positional
+arguments. However, it has significant limitations, citing its author:
+
+> Three features that have no hope of being accommodated within the
+> current design are:
+>
+> - Leading zeros (or any other non-space padding)
+> - Octal/hexadecimal encoding
+> - Runtime width/alignment specification
+
+It is also quite big and has a heavy dependency, STLSoft, which might be
+too restrictive for using it in some projects.
+
+## Boost Spirit.Karma
+
+This is not a formatting library but I decided to include it here for
+completeness. As iostreams, it suffers from the problem of mixing
+verbatim text with arguments. The library is pretty fast, but slower on
+integer formatting than `fmt::format_to` with format string compilation
+on Karma\'s own benchmark, see [Converting a hundred million integers to
+strings per
+second](http://www.zverovich.net/2020/06/13/fast-int-to-string-revisited.html).
+
+# License
+
+{fmt} is distributed under the MIT
+[license](https://github.com/fmtlib/fmt/blob/master/LICENSE).
+
+# Documentation License
+
+The [Format String Syntax](https://fmt.dev/latest/syntax.html) section
+in the documentation is based on the one from Python [string module
+documentation](https://docs.python.org/3/library/string.html#module-string).
+For this reason, the documentation is distributed under the Python
+Software Foundation license available in
+[doc/python-license.txt](https://raw.github.com/fmtlib/fmt/master/doc/python-license.txt).
+It only applies if you distribute the documentation of {fmt}.
+
+# Maintainers
+
+The {fmt} library is maintained by Victor Zverovich
+([vitaut](https://github.com/vitaut)) with contributions from many other
+people. See
+[Contributors](https://github.com/fmtlib/fmt/graphs/contributors) and
+[Releases](https://github.com/fmtlib/fmt/releases) for some of the
+names. Let us know if your contribution is not listed or mentioned
+incorrectly and we\'ll make it right.
+
+# Security Policy
+
+To report a security issue, please disclose it at [security
+advisory](https://github.com/fmtlib/fmt/security/advisories/new).
+
+This project is maintained by a team of volunteers on a
+reasonable-effort basis. As such, please give us at least 90 days to
+work on a fix before public exposure.

README.rst

@@ -1,477 +0,0 @@
-{fmt}
-=====
-
-.. image:: https://travis-ci.org/fmtlib/fmt.png?branch=master
-   :target: https://travis-ci.org/fmtlib/fmt
-
-.. image:: https://ci.appveyor.com/api/projects/status/ehjkiefde6gucy1v
-   :target: https://ci.appveyor.com/project/vitaut/fmt
-   
-.. image:: https://badges.gitter.im/Join%20Chat.svg
-   :alt: Join the chat at https://gitter.im/fmtlib/fmt
-   :target: https://gitter.im/fmtlib/fmt
-
-**{fmt}** is an open-source formatting library for C++.
-It can be used as a safe and fast alternative to (s)printf and IOStreams.
-
-`Documentation <http://fmtlib.net/latest/>`__
-
-This is a development branch that implements the C++ standards proposal `P0645
-Text Formatting <http://fmtlib.net/Text%20Formatting.html>`__.
-Released versions are available from the `Releases page
-<https://github.com/fmtlib/fmt/releases>`__.
-
-Features
---------
-
-* Replacement-based `format API <http://fmtlib.net/dev/api.html>`_ with
-  positional arguments for localization.
-* `Format string syntax <http://fmtlib.net/dev/syntax.html>`_ similar to the one
-  of `str.format <https://docs.python.org/2/library/stdtypes.html#str.format>`_
-  in Python.
-* Safe `printf implementation
-  <http://fmtlib.net/latest/api.html#printf-formatting-functions>`_ including
-  the POSIX extension for positional arguments.
-* Support for user-defined types.
-* High speed: performance of the format API is close to that of glibc's `printf
-  <http://en.cppreference.com/w/cpp/io/c/fprintf>`_ and better than the
-  performance of IOStreams. See `Speed tests`_ and
-  `Fast integer to string conversion in C++
-  <http://zverovich.net/2013/09/07/integer-to-string-conversion-in-cplusplus.html>`_.
-* Small code size both in terms of source code (the minimum configuration
-  consists of just three header files, ``core.h``, ``format.h`` and
-  ``format-inl.h``) and compiled code. See `Compile time and code bloat`_.
-* Reliability: the library has an extensive set of `unit tests
-  <https://github.com/fmtlib/fmt/tree/master/test>`_.
-* Safety: the library is fully type safe, errors in format strings can be
-  reported at compile time, automatic memory management prevents buffer overflow
-  errors.
-* Ease of use: small self-contained code base, no external dependencies,
-  permissive BSD `license
-  <https://github.com/fmtlib/fmt/blob/master/LICENSE.rst>`_
-* `Portability <http://fmtlib.net/latest/index.html#portability>`_ with
-  consistent output across platforms and support for older compilers.
-* Clean warning-free codebase even on high warning levels
-  (``-Wall -Wextra -pedantic``).
-* Support for wide strings.
-* Optional header-only configuration enabled with the ``FMT_HEADER_ONLY`` macro.
-
-See the `documentation <http://fmtlib.net/latest/>`_ for more details.
-
-Examples
---------
-
-This prints ``Hello, world!`` to stdout:
-
-.. code:: c++
-
-    fmt::print("Hello, {}!", "world");  // uses Python-like format string syntax
-    fmt::printf("Hello, %s!", "world"); // uses printf format string syntax
-
-Arguments can be accessed by position and arguments' indices can be repeated:
-
-.. code:: c++
-
-    std::string s = fmt::format("{0}{1}{0}", "abra", "cad");
-    // s == "abracadabra"
-
-Format strings can be checked at compile time:
-
-.. code:: c++
-
-    // test.cc
-    #include <fmt/format.h>
-    std::string s = fmt::format(fmt("{2}"), 42);
-
-.. code::
-
-    $ g++ -Iinclude test.cc -std=c++14
-    ...
-    test.cc:2:22: note: in instantiation of function template specialization 'fmt::format<S, int>' requested here
-    std::string s = fmt::format(fmt("{2}"), 42);
-                         ^
-    include/fmt/core.h:749:19: note: non-constexpr function 'on_error' cannot be used in a constant expression
-        ErrorHandler::on_error(message);
-                      ^
-    include/fmt/format.h:2081:16: note: in call to '&checker.context_->on_error(&"argument index out of range"[0])'
-          context_.on_error("argument index out of range");
-                   ^
-
-{fmt} can be used as a safe portable replacement for ``itoa``
-(`godbolt <https://godbolt.org/g/NXmpU4>`_):
-
-.. code:: c++
-
-    fmt::memory_buffer buf;
-    format_to(buf, "{}", 42);    // replaces itoa(42, buffer, 10)
-    format_to(buf, "{:x}", 42);  // replaces itoa(42, buffer, 16)
-    // access the string using to_string(buf) or buf.data()
-
-An object of any user-defined type for which there is an overloaded
-:code:`std::ostream` insertion operator (``operator<<``) can be formatted:
-
-.. code:: c++
-
-    #include "fmt/ostream.h"
-
-    class Date {
-      int year_, month_, day_;
-     public:
-      Date(int year, int month, int day) : year_(year), month_(month), day_(day) {}
-
-      friend std::ostream &operator<<(std::ostream &os, const Date &d) {
-        return os << d.year_ << '-' << d.month_ << '-' << d.day_;
-      }
-    };
-
-    std::string s = fmt::format("The date is {}", Date(2012, 12, 9));
-    // s == "The date is 2012-12-9"
-
-You can create your own functions similar to `format
-<http://fmtlib.net/latest/api.html#format>`_ and
-`print <http://fmtlib.net/latest/api.html#print>`_
-which take arbitrary arguments (`godbolt <https://godbolt.org/g/MHjHVf>`_):
-
-.. code:: c++
-
-    // Prints formatted error message.
-    void vreport_error(const char *format, fmt::format_args args) {
-      fmt::print("Error: ");
-      fmt::vprint(format, args);
-    }
-    template <typename... Args>
-    void report_error(const char *format, const Args & ... args) {
-      vreport_error(format, fmt::make_format_args(args...));
-    }
-
-    report_error("file not found: {}", path);
-
-Note that ``vreport_error`` is not parameterized on argument types which can
-improve compile times and reduce code size compared to fully parameterized version.
-
-Projects using this library
----------------------------
-
-* `0 A.D. <http://play0ad.com/>`_: A free, open-source, cross-platform real-time strategy game
-
-* `AMPL/MP <https://github.com/ampl/mp>`_:
-  An open-source library for mathematical programming
-  
-* `AvioBook <https://www.aviobook.aero/en>`_: A comprehensive aircraft operations suite
-
-* `CUAUV <http://cuauv.org/>`_: Cornell University's autonomous underwater vehicle
-
-* `HarpyWar/pvpgn <https://github.com/pvpgn/pvpgn-server>`_:
-  Player vs Player Gaming Network with tweaks
-
-* `KBEngine <http://kbengine.org/>`_: An open-source MMOG server engine
-
-* `Keypirinha <http://keypirinha.com/>`_: A semantic launcher for Windows
-
-* `Kodi <https://kodi.tv/>`_ (formerly xbmc): Home theater software
-
-* `Lifeline <https://github.com/peter-clark/lifeline>`_: A 2D game
-
-* `Drake <http://drake.mit.edu/>`_: A planning, control, and analysis toolbox
-  for nonlinear dynamical systems (MIT)
-
-* `Envoy <https://lyft.github.io/envoy/>`_: C++ L7 proxy and communication bus
-  (Lyft)
-
-* `FiveM <https://fivem.net/>`_: a modification framework for GTA V
-
-* `MongoDB Smasher <https://github.com/duckie/mongo_smasher>`_: A small tool to
-  generate randomized datasets
-
-* `OpenSpace <http://openspaceproject.com/>`_: An open-source astrovisualization
-  framework
-
-* `PenUltima Online (POL) <http://www.polserver.com/>`_:
-  An MMO server, compatible with most Ultima Online clients
-
-* `quasardb <https://www.quasardb.net/>`_: A distributed, high-performance,
-  associative database
-
-* `readpe <https://bitbucket.org/sys_dev/readpe>`_: Read Portable Executable
-
-* `redis-cerberus <https://github.com/HunanTV/redis-cerberus>`_: A Redis cluster proxy
-
-* `Saddy <https://github.com/mamontov-cpp/saddy-graphics-engine-2d>`_:
-  Small crossplatform 2D graphic engine
-
-* `Salesforce Analytics Cloud <http://www.salesforce.com/analytics-cloud/overview/>`_:
-  Business intelligence software
-
-* `Scylla <http://www.scylladb.com/>`_: A Cassandra-compatible NoSQL data store that can handle
-  1 million transactions per second on a single server
-
-* `Seastar <http://www.seastar-project.org/>`_: An advanced, open-source C++ framework for
-  high-performance server applications on modern hardware
-
-* `spdlog <https://github.com/gabime/spdlog>`_: Super fast C++ logging library
-
-* `Stellar <https://www.stellar.org/>`_: Financial platform
-
-* `Touch Surgery <https://www.touchsurgery.com/>`_: Surgery simulator
-
-* `TrinityCore <https://github.com/TrinityCore/TrinityCore>`_: Open-source MMORPG framework
-
-`More... <https://github.com/search?q=cppformat&type=Code>`_
-
-If you are aware of other projects using this library, please let me know
-by `email <mailto:victor.zverovich@gmail.com>`_ or by submitting an
-`issue <https://github.com/fmtlib/fmt/issues>`_.
-
-Motivation
-----------
-
-So why yet another formatting library?
-
-There are plenty of methods for doing this task, from standard ones like
-the printf family of function and IOStreams to Boost Format library and
-FastFormat. The reason for creating a new library is that every existing
-solution that I found either had serious issues or didn't provide
-all the features I needed.
-
-Printf
-~~~~~~
-
-The good thing about printf is that it is pretty fast and readily available
-being a part of the C standard library. The main drawback is that it
-doesn't support user-defined types. Printf also has safety issues although
-they are mostly solved with `__attribute__ ((format (printf, ...))
-<http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html>`_ in GCC.
-There is a POSIX extension that adds positional arguments required for
-`i18n <https://en.wikipedia.org/wiki/Internationalization_and_localization>`_
-to printf but it is not a part of C99 and may not be available on some
-platforms.
-
-IOStreams
-~~~~~~~~~
-
-The main issue with IOStreams is best illustrated with an example:
-
-.. code:: c++
-
-    std::cout << std::setprecision(2) << std::fixed << 1.23456 << "\n";
-
-which is a lot of typing compared to printf:
-
-.. code:: c++
-
-    printf("%.2f\n", 1.23456);
-
-Matthew Wilson, the author of FastFormat, referred to this situation with
-IOStreams as "chevron hell". IOStreams doesn't support positional arguments
-by design.
-
-The good part is that IOStreams supports user-defined types and is safe
-although error reporting is awkward.
-
-Boost Format library
-~~~~~~~~~~~~~~~~~~~~
-
-This is a very powerful library which supports both printf-like format
-strings and positional arguments. The main its drawback is performance.
-According to various benchmarks it is much slower than other methods
-considered here. Boost Format also has excessive build times and severe
-code bloat issues (see `Benchmarks`_).
-
-FastFormat
-~~~~~~~~~~
-
-This is an interesting library which is fast, safe and has positional
-arguments. However it has significant limitations, citing its author:
-
-    Three features that have no hope of being accommodated within the
-    current design are:
-
-    * Leading zeros (or any other non-space padding)
-    * Octal/hexadecimal encoding
-    * Runtime width/alignment specification
-
-It is also quite big and has a heavy dependency, STLSoft, which might be
-too restrictive for using it in some projects.
-
-Loki SafeFormat
-~~~~~~~~~~~~~~~
-
-SafeFormat is a formatting library which uses printf-like format strings
-and is type safe. It doesn't support user-defined types or positional
-arguments. It makes unconventional use of ``operator()`` for passing
-format arguments.
-
-Tinyformat
-~~~~~~~~~~
-
-This library supports printf-like format strings and is very small and
-fast. Unfortunately it doesn't support positional arguments and wrapping
-it in C++98 is somewhat difficult. Also its performance and code compactness
-are limited by IOStreams.
-
-Boost Spirit.Karma
-~~~~~~~~~~~~~~~~~~
-
-This is not really a formatting library but I decided to include it here
-for completeness. As IOStreams it suffers from the problem of mixing
-verbatim text with arguments. The library is pretty fast, but slower
-on integer formatting than ``fmt::Writer`` on Karma's own benchmark,
-see `Fast integer to string conversion in C++
-<http://zverovich.net/2013/09/07/integer-to-string-conversion-in-cplusplus.html>`_.
-
-Benchmarks
-----------
-
-Speed tests
-~~~~~~~~~~~
-
-The following speed tests results were generated by building
-``tinyformat_test.cpp`` on Ubuntu GNU/Linux 14.04.1 with
-``g++-4.8.2 -O3 -DSPEED_TEST -DHAVE_FORMAT``, and taking the best of three
-runs.  In the test, the format string ``"%0.10f:%04d:%+g:%s:%p:%c:%%\n"`` or
-equivalent is filled 2000000 times with output sent to ``/dev/null``; for
-further details see the `source
-<https://github.com/fmtlib/format-benchmark/blob/master/tinyformat_test.cpp>`_.
-
-================= ============= ===========
-Library           Method        Run Time, s
-================= ============= ===========
-libc              printf          1.35
-libc++            std::ostream    3.42
-fmt 534bff7       fmt::print      1.56
-tinyformat 2.0.1  tfm::printf     3.73
-Boost Format 1.54 boost::format   8.44
-Folly Format      folly::format   2.54
-================= ============= ===========
-
-As you can see ``boost::format`` is much slower than the alternative methods; this
-is confirmed by `other tests <http://accu.org/index.php/journals/1539>`_.
-Tinyformat is quite good coming close to IOStreams.  Unfortunately tinyformat
-cannot be faster than the IOStreams because it uses them internally.
-Performance of fmt is close to that of printf, being `faster than printf on integer
-formatting <http://zverovich.net/2013/09/07/integer-to-string-conversion-in-cplusplus.html>`_,
-but slower on floating-point formatting which dominates this benchmark.
-
-Compile time and code bloat
-~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-The script `bloat-test.py
-<https://github.com/fmtlib/format-benchmark/blob/master/bloat-test.py>`_
-from `format-benchmark <https://github.com/fmtlib/format-benchmark>`_
-tests compile time and code bloat for nontrivial projects.
-It generates 100 translation units and uses ``printf()`` or its alternative
-five times in each to simulate a medium sized project.  The resulting
-executable size and compile time (Apple LLVM version 8.1.0 (clang-802.0.42),
-macOS Sierra, best of three) is shown in the following tables.
-
-**Optimized build (-O3)**
-
-============= =============== ==================== ==================
-Method        Compile Time, s Executable size, KiB Stripped size, KiB
-============= =============== ==================== ==================
-printf                    2.7                   29                 26
-printf+string            18.4                   29                 26
-IOStreams                34.6                   59                 55
-fmt                      22.0                   37                 34
-tinyformat               51.8                  103                 97
-Boost Format            120.5                  762                739
-Folly Format            158.7                  102                 87
-============= =============== ==================== ==================
-
-As you can see, fmt has 60% less overhead in terms of resulting binary code
-size compared to IOStreams and comes pretty close to ``printf``. Boost Format
-has by far the largest overheads.
-
-``printf+string`` is the same as ``printf`` but with extra ``<string>``
-include to measure the overhead of the latter.
-
-**Non-optimized build**
-
-============= =============== ==================== ==================
-Method        Compile Time, s Executable size, KiB Stripped size, KiB
-============= =============== ==================== ==================
-printf                    2.4                   33                 30
-printf+string            18.5                   33                 30
-IOStreams                31.9                   56                 52
-fmt                      20.9                   56                 51
-tinyformat               38.9                   88                 82
-Boost Format             64.8                  366                304
-Folly Format            113.5                  442                428
-============= =============== ==================== ==================
-
-``libc``, ``lib(std)c++`` and ``libfmt`` are all linked as shared
-libraries to compare formatting function overhead only. Boost Format
-and tinyformat are header-only libraries so they don't provide any
-linkage options.
-
-Running the tests
-~~~~~~~~~~~~~~~~~
-
-Please refer to `Building the library`__ for the instructions on how to build
-the library and run the unit tests.
-
-__ http://fmtlib.net/latest/usage.html#building-the-library
-
-Benchmarks reside in a separate repository,
-`format-benchmarks <https://github.com/fmtlib/format-benchmark>`_,
-so to run the benchmarks you first need to clone this repository and
-generate Makefiles with CMake::
-
-    $ git clone --recursive https://github.com/fmtlib/format-benchmark.git
-    $ cd format-benchmark
-    $ cmake .
-
-Then you can run the speed test::
-
-    $ make speed-test
-
-or the bloat test::
-
-    $ make bloat-test
-
-License
--------
-
-fmt is distributed under the BSD `license
-<https://github.com/fmtlib/fmt/blob/master/LICENSE.rst>`_.
-
-The `Format String Syntax
-<http://fmtlib.net/latest/syntax.html>`_
-section in the documentation is based on the one from Python `string module
-documentation <https://docs.python.org/3/library/string.html#module-string>`_
-adapted for the current library. For this reason the documentation is
-distributed under the Python Software Foundation license available in
-`doc/python-license.txt
-<https://raw.github.com/fmtlib/fmt/master/doc/python-license.txt>`_.
-It only applies if you distribute the documentation of fmt.
-
-Acknowledgments
----------------
-
-The fmt library is maintained by Victor Zverovich (`vitaut
-<https://github.com/vitaut>`_) and Jonathan Müller (`foonathan
-<https://github.com/foonathan>`_) with contributions from many other people.
-See `Contributors <https://github.com/fmtlib/fmt/graphs/contributors>`_ and
-`Releases <https://github.com/fmtlib/fmt/releases>`_ for some of the names.
-Let us know if your contribution is not listed or mentioned incorrectly and
-we'll make it right.
-
-The benchmark section of this readme file and the performance tests are taken
-from the excellent `tinyformat <https://github.com/c42f/tinyformat>`_ library
-written by Chris Foster.  Boost Format library is acknowledged transitively
-since it had some influence on tinyformat.
-Some ideas used in the implementation are borrowed from `Loki
-<http://loki-lib.sourceforge.net/>`_ SafeFormat and `Diagnostic API
-<http://clang.llvm.org/doxygen/classclang_1_1Diagnostic.html>`_ in
-`Clang <http://clang.llvm.org/>`_.
-Format string syntax and the documentation are based on Python's `str.format
-<http://docs.python.org/2/library/stdtypes.html#str.format>`_.
-Thanks `Doug Turnbull <https://github.com/softwaredoug>`_ for his valuable
-comments and contribution to the design of the type-safe API and
-`Gregory Czajkowski <https://github.com/gcflymoto>`_ for implementing binary
-formatting. Thanks `Ruslan Baratov <https://github.com/ruslo>`_ for comprehensive
-`comparison of integer formatting algorithms <https://github.com/ruslo/int-dec-format-tests>`_
-and useful comments regarding performance, `Boris Kaul <https://github.com/localvoid>`_ for
-`C++ counting digits benchmark <https://github.com/localvoid/cxx-benchmark-count-digits>`_.
-Thanks to `CarterLi <https://github.com/CarterLi>`_ for contributing various
-improvements to the code.

doc/CMakeLists.txt

@@ -1,12 +1,26 @@
-find_program(DOXYGEN doxygen)
+find_program(DOXYGEN doxygen
+  PATHS "$ENV{ProgramFiles}/doxygen/bin"
+        "$ENV{ProgramFiles\(x86\)}/doxygen/bin")
 if (NOT DOXYGEN)
   message(STATUS "Target 'doc' disabled (requires doxygen)")
   return ()
 endif ()
 
-add_custom_target(doc
-  COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/build.py ${FMT_VERSION}
-  SOURCES api.rst syntax.rst build.py conf.py _templates/layout.html)
+# Find the Python interpreter and set the PYTHON_EXECUTABLE variable.
+if (CMAKE_VERSION VERSION_LESS 3.12)
+  # This logic is deprecated in CMake after 3.12.
+  find_package(PythonInterp QUIET REQUIRED)
+else ()
+  find_package(Python QUIET REQUIRED)
+  set(PYTHON_EXECUTABLE ${Python_EXECUTABLE})
+endif ()
 
+add_custom_target(doc
+  COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/build.py
+                               ${FMT_VERSION}
+  SOURCES api.rst syntax.rst usage.rst build.py conf.py _templates/layout.html)
+
+include(GNUInstallDirs)
 install(DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/html/
-        DESTINATION share/doc/fmt OPTIONAL)
+        DESTINATION ${CMAKE_INSTALL_DATAROOTDIR}/doc/fmt OPTIONAL
+        PATTERN ".doctrees" EXCLUDE)

doc/_templates/layout.html

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

doc/api.rst

@@ -6,57 +6,296 @@ 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, output iterator and user-defined type support
-* :ref:`fmt/time.h <time-api>`: date and time formatting
+* :ref:`fmt/core.h <core-api>`: the core API providing main formatting functions
+  for ``char``/UTF-8 with C++20 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/std.h <std-api>`: formatters for standard library types
+* :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/args.h <args-api>`: dynamic argument lists
 * :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_`` or ``fmt``.
+macros have prefix ``FMT_``.
 
 .. _core-api:
 
 Core API
 ========
 
-``fmt/core.h`` defines the core API which provides argument handling facilities
-and a lightweight subset of formatting functions.
+``fmt/core.h`` defines the core API which provides main formatting functions
+for ``char``/UTF-8 with C++20 compile-time checks. It has minimal include
+dependencies for better compile times. This header is only beneficial when
+using {fmt} as a library (the default) and not in the header-only mode.
+It also provides ``formatter`` specializations for built-in and string types.
 
 The following functions use :ref:`format string syntax <syntax>`
-imilar 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.
+similar to that of Python's `str.format
+<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.
+*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.
 
+I/O errors are reported as `std::system_error
+<https://en.cppreference.com/w/cpp/error/system_error>`_ exceptions unless
+specified otherwise.
+
 .. _format:
 
-.. doxygenfunction:: format(string_view, const Args&...)
-.. doxygenfunction:: vformat(string_view, format_args)
+.. 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(string_view, const 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 *, string_view, const 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)
 
-Named arguments
+Compile-Time Format String Checks
+---------------------------------
+
+Compile-time format string checks are enabled by default on compilers
+that support C++20 ``consteval``. On older compilers you can use the
+:ref:`FMT_STRING <legacy-checks>`: macro defined in ``fmt/format.h`` instead.
+
+Unused arguments are allowed as in Python's `str.format` and ordinary functions.
+
+.. doxygenclass:: fmt::basic_format_string
+   :members:
+
+.. doxygentypedef:: fmt::format_string
+
+.. doxygenfunction:: fmt::runtime(string_view) -> runtime_format_string<>
+
+.. _udt:
+
+Formatting User-Defined Types
+-----------------------------
+
+The {fmt} library provides formatters for many standard C++ types.
+See :ref:`fmt/ranges.h <ranges-api>` for ranges and tuples including standard
+containers such as ``std::vector``, :ref:`fmt/chrono.h <chrono-api>` for date
+and time formatting and :ref:`fmt/std.h <std-api>` for other standard library
+types.
+
+There are two ways to make a user-defined type formattable: providing a
+``format_as`` function or specializing the ``formatter`` struct template.
+
+Use ``format_as`` if you want to make your type formattable as some other type
+with the same format specifiers. The ``format_as`` function should take an
+object of your type and return an object of a formattable type. It should be
+defined in the same namespace as your type.
+
+Example (https://godbolt.org/z/nvME4arz8)::
+
+  #include <fmt/format.h>
+
+  namespace kevin_namespacy {
+  enum class film {
+    house_of_cards, american_beauty, se7en = 7
+  };
+  auto format_as(film f) { return fmt::underlying(f); }
+  }
+
+  int main() {
+    fmt::print("{}\n", kevin_namespacy::film::se7en); // prints "7"
+  }
+
+Using specialization is more complex but gives you full control over parsing and
+formatting. To use this method specialize the ``formatter`` struct template for
+your type and implement ``parse`` and ``format`` methods.
+
+The recommended way of defining a formatter is by reusing an existing one via
+inheritance or composition. This way you can support standard format specifiers
+without implementing them yourself. For example::
+
+  // color.h:
+  #include <fmt/core.h>
+
+  enum class color {red, green, blue};
+
+  template <> struct fmt::formatter<color>: formatter<string_view> {
+    // parse is inherited from formatter<string_view>.
+
+    auto format(color c, format_context& ctx) const;
+  };
+
+  // color.cc:
+  #include "color.h"
+  #include <fmt/format.h>
+
+  auto fmt::formatter<color>::format(color c, format_context& ctx) const {
+    string_view name = "unknown";
+    switch (c) {
+    case color::red:   name = "red"; break;
+    case color::green: name = "green"; break;
+    case color::blue:  name = "blue"; break;
+    }
+    return formatter<string_view>::format(name, ctx);
+  }
+
+Note that ``formatter<string_view>::format`` is defined in ``fmt/format.h`` so
+it has to be included in the source file. Since ``parse`` is inherited from
+``formatter<string_view>`` it will recognize all string format specifications,
+for example
+
+.. code-block:: c++
+
+   fmt::format("{:>10}", color::blue)
+
+will return ``"      blue"``.
+
+The experimental ``nested_formatter`` provides an easy way of applying a
+formatter to one or more subobjects.
+
+For example::
+
+  #include <fmt/format.h>
+
+  struct point {
+    double x, y;
+  };
+
+  template <>
+  struct fmt::formatter<point> : nested_formatter<double> {
+    auto format(point p, format_context& ctx) const {
+      return write_padded(ctx, [=](auto out) {
+        return format_to(out, "({}, {})", nested(p.x), nested(p.y));
+      });
+    }
+  };
+
+  int main() {
+    fmt::print("[{:>20.2f}]", point{1, 2});
+  }
+
+prints::
+
+  [          (1.00, 2.00)]
+
+Notice that fill, align and width are applied to the whole object which is the
+recommended behavior while the remaining specifiers apply to elements.
+
+In general the formatter has the following form::
+
+  template <> struct fmt::formatter<T> {
+    // Parses format specifiers and stores them in the formatter.
+    //
+    // [ctx.begin(), ctx.end()) is a, possibly empty, character range that
+    // contains a part of the format string starting from the format
+    // specifications to be parsed, e.g. in
+    //
+    //   fmt::format("{:f} continued", ...);
+    //
+    // the range will contain "f} continued". The formatter should parse
+    // specifiers until '}' or the end of the range. In this example the
+    // formatter should parse the 'f' specifier and return an iterator
+    // pointing to '}'.
+    constexpr auto parse(format_parse_context& ctx)
+      -> format_parse_context::iterator;
+
+    // Formats value using the parsed format specification stored in this
+    // formatter and writes the output to ctx.out().
+    auto format(const T& value, format_context& ctx) const
+      -> format_context::iterator;
+  };
+
+It is recommended to at least support fill, align and width that apply to the
+whole object and have the same semantics as in standard formatters.
+
+You can also write a formatter for a hierarchy of classes::
+
+  // demo.h:
+  #include <type_traits>
+  #include <fmt/core.h>
+
+  struct A {
+    virtual ~A() {}
+    virtual std::string name() const { return "A"; }
+  };
+
+  struct B : A {
+    virtual std::string name() const { return "B"; }
+  };
+
+  template <typename T>
+  struct fmt::formatter<T, std::enable_if_t<std::is_base_of<A, T>::value, char>> :
+      fmt::formatter<std::string> {
+    auto format(const A& a, format_context& ctx) const {
+      return fmt::formatter<std::string>::format(a.name(), ctx);
+    }
+  };
+
+  // demo.cc:
+  #include "demo.h"
+  #include <fmt/format.h>
+
+  int main() {
+    B b;
+    A& a = b;
+    fmt::print("{}", a); // prints "B"
+  }
+
+Providing both a ``formatter`` specialization and a ``format_as`` overload is
+disallowed.
+
+Named Arguments
 ---------------
 
-.. doxygenfunction:: fmt::arg(string_view, const T&)
+.. doxygenfunction:: fmt::arg(const S&, const T&)
 
-Argument lists
+Named arguments are not supported in compile-time checks at the moment.
+
+Argument Lists
 --------------
 
+You can create your own formatting function with compile-time checks and small
+binary footprint, for example (https://godbolt.org/z/vajfWEG4b):
+
+.. code:: c++
+
+    #include <fmt/core.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... T>
+    void log(const char* file, int line, fmt::format_string<T...> format, T&&... args) {
+      vlog(file, line, format, fmt::make_format_args(args...));
+    }
+
+    #define MY_LOG(format, ...) log(__FILE__, __LINE__, 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_format_args(const Args&...)
 
 .. doxygenclass:: fmt::format_arg_store
@@ -65,11 +304,30 @@ 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_parse_context
+   :members:
+
+.. doxygenclass:: fmt::basic_format_context
+   :members:
+
+.. doxygentypedef:: fmt::format_context
+
+.. _args-api:
+
+Dynamic Argument Lists
+----------------------
+
+The header ``fmt/args.h`` provides ``dynamic_format_arg_store``, a builder-like
+API that can be used to construct format argument lists dynamically.
+
+.. doxygenclass:: fmt::dynamic_format_arg_store
+   :members:
+
 Compatibility
 -------------
 
@@ -77,108 +335,58 @@ Compatibility
    :members:
 
 .. doxygentypedef:: fmt::string_view
-.. doxygentypedef:: fmt::wstring_view
 
 .. _format-api:
 
 Format API
 ==========
 
-``fmt/format.h`` defines the full format API providing compile-time format
-string checks, output iterator and user-defined type support.
+``fmt/format.h`` defines the full format API providing additional formatting
+functions and locale support.
 
-Compile-time format string checks
----------------------------------
-
-.. doxygendefine:: fmt
-
-Formatting user-defined types
------------------------------
-
-To make a user-defined type formattable, specialize the ``formatter<T>`` struct
-template and implement ``parse`` and ``format`` methods::
-
-  #include <fmt/format.h>
-
-  struct point { double x, y; };
-
-  namespace fmt {
-  template <>
-  struct formatter<point> {
-    template <typename ParseContext>
-    constexpr auto parse(ParseContext &ctx) { return ctx.begin(); }
-
-    template <typename FormatContext>
-    auto format(const point &p, FormatContext &ctx) {
-      return format_to(ctx.begin(), "({:.1f}, {:.1f})", p.x, p.y);
-    }
-  };
-  }
-
-Then you can pass objects of type ``point`` to any formatting function::
-
-  point p = {1, 2};
-  std::string s = fmt::format("{}", p);
-  // s == "(1.0, 2.0)"
-
-In the example above the ``formatter<point>::parse`` function ignores the
-contents of the format string referred to by ``ctx.begin()`` so the object will
-always be formatted in the same way. See ``formatter<tm>::parse`` in
-:file:`fmt/time.h` for an advanced example of how to parse the format string and
-customize the formatted output.
-
-This section shows how to define a custom format function for a user-defined
-type. The next section describes how to get ``fmt`` to use a conventional stream
-output ``operator<<`` when one is defined for a user-defined type.
-
-Output iterator support
------------------------
-
-.. doxygenfunction:: fmt::format_to(OutputIt, string_view, const Args&...)
-.. doxygenfunction:: fmt::format_to_n(OutputIt, size_t, string_view, const Args&...)
-.. doxygenstruct:: fmt::format_to_n_result
-   :members:
-
-Literal-based API
+Literal-Based API
 -----------------
 
 The following user-defined literals are defined in ``fmt/format.h``.
 
-.. doxygenfunction:: operator""_format(const char *, std::size_t)
-
-.. doxygenfunction:: operator""_a(const char *, std::size_t)
+.. doxygenfunction:: operator""_a()
 
 Utilities
 ---------
 
-.. doxygenfunction:: fmt::formatted_size(string_view, const Args&...)
+.. doxygenfunction:: fmt::ptr(T p) -> const void*
+.. doxygenfunction:: fmt::ptr(const std::unique_ptr<T, Deleter> &p) -> const void*
+.. doxygenfunction:: fmt::ptr(const std::shared_ptr<T> &p) -> const void*
 
-.. doxygenfunction:: fmt::to_string(const T&)
+.. doxygenfunction:: fmt::underlying(Enum e) -> typename std::underlying_type<Enum>::type
 
-.. doxygenfunction:: fmt::to_wstring(const T&)
+.. doxygenfunction:: fmt::to_string(const T &value) -> std::string
+
+.. doxygenfunction:: fmt::join(Range &&range, string_view sep) -> join_view<detail::iterator_t<Range>, detail::sentinel_t<Range>>
+
+.. doxygenfunction:: fmt::join(It begin, Sentinel end, string_view sep) -> join_view<It, Sentinel>
+
+.. doxygenfunction:: fmt::group_digits(T value) -> group_digits_view<T>
+
+.. doxygenclass:: fmt::detail::buffer
+   :members:
 
 .. doxygenclass:: fmt::basic_memory_buffer
    :protected-members:
    :members:
 
-System errors
+System Errors
 -------------
 
-fmt does not use ``errno`` to communicate errors to the user, but it may call
-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
+Custom Allocators
 -----------------
 
 The {fmt} library supports custom dynamic memory allocators.
@@ -196,126 +404,275 @@ 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);
     }
 
     template <typename ...Args>
     inline custom_string format(custom_allocator alloc,
                                 fmt::string_view format_str,
-                                const Args & ... args) {
+                                const Args& ... args) {
       return vformat(alloc, format_str, fmt::make_format_args(args...));
     }
 
-The allocator will be used for the output container only. If you are using named
-arguments, the container that stores pointers to them will be allocated using
-the default allocator. Also floating-point formatting falls back on ``sprintf``
-which may do allocations.
+The allocator will be used for the output container only. Formatting functions
+normally don't do any allocations for built-in and string types except for
+non-default floating-point formatting that occasionally falls back on
+``sprintf``.
 
-Custom formatting of built-in types
------------------------------------
+Locale
+------
 
-It is possible to change the way arguments are formatted by providing a
-custom argument formatter class::
+All formatting is locale-independent by default. Use the ``'L'`` format
+specifier to insert the appropriate number separator characters from the
+locale::
 
-  using arg_formatter =
-    fmt::arg_formatter<fmt::back_insert_range<fmt::internal::buffer>>;
+  #include <fmt/core.h>
+  #include <locale>
 
-  // A custom argument formatter that formats negative integers as unsigned
-  // with the ``x`` format specifier.
-  class custom_arg_formatter : public arg_formatter {
-   public:
-    custom_arg_formatter(fmt::format_context &ctx, fmt::format_specs &spec)
-      : arg_formatter(ctx, spec) {}
+  std::locale::global(std::locale("en_US.UTF-8"));
+  auto s = fmt::format("{:L}", 1000000);  // s == "1,000,000"
 
-    using arg_formatter::operator();
+``fmt/format.h`` provides the following overloads of formatting functions that
+take ``std::locale`` as a parameter. The locale type is a template parameter to
+avoid the expensive ``<locale>`` include.
 
-    void operator()(int value) {
-      if (spec().type() == 'x')
-        (*this)(static_cast<unsigned>(value)); // convert to unsigned and format
-      else
-        arg_formatter::operator()(value);
-    }
-  };
+.. doxygenfunction:: format(const Locale& loc, format_string<T...> fmt, T&&... args) -> std::string
+.. doxygenfunction:: format_to(OutputIt out, const Locale& loc, format_string<T...> fmt, T&&... args) -> OutputIt
+.. doxygenfunction:: formatted_size(const Locale& loc, format_string<T...> fmt, T&&... args) -> size_t
 
-  std::string custom_vformat(fmt::string_view format_str, fmt::format_args args) {
-    fmt::memory_buffer buffer;
-    // Pass custom argument formatter as a template arg to vformat_to.
-    fmt::vformat_to<custom_arg_formatter>(buffer, format_str, args);
-    return fmt::to_string(buffer);
-  }
+.. _legacy-checks:
 
-  template <typename ...Args>
-  inline std::string custom_format(
-      fmt::string_view format_str, const Args &... args) {
-    return custom_vformat(format_str, fmt::make_format_args(args...));
-  }
+Legacy Compile-Time Format String Checks
+----------------------------------------
 
-  std::string s = custom_format("{:x}", -42); // s == "ffffffd6"
+``FMT_STRING`` enables compile-time checks on older compilers. It requires C++14
+or later and is a no-op in C++11.
 
-.. doxygenclass:: fmt::arg_formatter
-   :members:
+.. doxygendefine:: FMT_STRING
 
-.. _time-api:
+To force the use of legacy compile-time checks, define the preprocessor variable
+``FMT_ENFORCE_COMPILE_STRING``. When set, functions accepting ``FMT_STRING``
+will fail to compile with regular strings.
 
-Date and time formatting
+.. _ranges-api:
+
+Range and Tuple Formatting
+==========================
+
+The library also supports convenient formatting of ranges and tuples::
+
+  #include <fmt/ranges.h>
+
+  std::tuple<char, int, float> t{'a', 1, 2.0f};
+  // Prints "('a', 1, 2.0)"
+  fmt::print("{}", t);
+
+
+NOTE: currently, the overload of ``fmt::join`` for iterables exists in the main
+``format.h`` header, but expect this to change in the future.
+
+Using ``fmt::join``, you can separate tuple elements with a custom separator::
+
+  #include <fmt/ranges.h>
+
+  std::tuple<int, char> t = {1, 'a'};
+  // Prints "1, a"
+  fmt::print("{}", fmt::join(t, ", "));
+
+.. _chrono-api:
+
+Date and Time Formatting
 ========================
 
-The library supports `strftime
-<http://en.cppreference.com/w/cpp/chrono/c/strftime>`_-like date and time
-formatting::
+``fmt/chrono.h`` provides formatters for
 
-  #include <fmt/time.h>
+* `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>`_
 
-  std::time_t t = std::time(nullptr);
-  // Prints "The date is 2016-04-29." (with the current date)
-  fmt::print("The date is {:%Y-%m-%d}.", *std::localtime(&t));
+The format syntax is described in :ref:`chrono-specs`.
 
-The format string syntax is described in the documentation of
-`strftime <http://en.cppreference.com/w/cpp/chrono/c/strftime>`_.
+**Example**::
+
+  #include <fmt/chrono.h>
+
+  int main() {
+    std::time_t t = std::time(nullptr);
+
+    // 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)
+
+.. _std-api:
+
+Standard Library Types Formatting
+=================================
+
+``fmt/std.h`` provides formatters for:
+
+* `std::filesystem::path <https://en.cppreference.com/w/cpp/filesystem/path>`_
+* `std::thread::id <https://en.cppreference.com/w/cpp/thread/thread/id>`_
+* `std::monostate <https://en.cppreference.com/w/cpp/utility/variant/monostate>`_
+* `std::variant <https://en.cppreference.com/w/cpp/utility/variant/variant>`_
+* `std::optional <https://en.cppreference.com/w/cpp/utility/optional>`_
+
+Formatting Variants
+-------------------
+
+A ``std::variant`` is only formattable if every variant alternative is formattable, and requires the
+``__cpp_lib_variant`` `library feature <https://en.cppreference.com/w/cpp/feature_test>`_.
+  
+**Example**::
+
+  #include <fmt/std.h>
+
+  std::variant<char, float> v0{'x'};
+  // Prints "variant('x')"
+  fmt::print("{}", v0);
+
+  std::variant<std::monostate, char> v1;
+  // Prints "variant(monostate)"
+
+.. _compile-api:
+
+Format String Compilation
+=========================
+
+``fmt/compile.h`` provides format string compilation enabled via the
+``FMT_COMPILE`` macro or the ``_cf`` user-defined literal. Format strings
+marked with ``FMT_COMPILE`` or ``_cf`` 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 ``format`` functions taking
+the format context type as a template parameter in their ``formatter``
+specializations. For example::
+
+  template <> struct fmt::formatter<point> {
+    constexpr auto parse(format_parse_context& ctx);
+
+    template <typename FormatContext>
+    auto format(const point& p, FormatContext& ctx) const;
+  };
+
+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
+
+.. doxygenfunction:: operator""_cf()
+
+.. _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)
+
+.. doxygenfunction:: styled(const T& value, text_style ts)
+
+.. _os-api:
+
+System APIs
+===========
+
+.. doxygenclass:: fmt::ostream
+   :members:
+
+.. doxygenfunction:: fmt::windows_error
 
 .. _ostream-api:
 
-``std::ostream`` support
+``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<<``).
+In order to make a type formattable via ``std::ostream`` you should provide a
+``formatter`` specialization inherited from ``ostream_formatter``::
 
   #include <fmt/ostream.h>
 
-  class date {
-    int year_, month_, day_;
-  public:
-    date(int year, int month, int day): year_(year), month_(month), day_(day) {}
+  struct date {
+    int year, month, day;
 
-    friend std::ostream &operator<<(std::ostream &os, const date &d) {
-      return os << d.year_ << '-' << d.month_ << '-' << d.day_;
+    friend std::ostream& operator<<(std::ostream& os, const date& d) {
+      return os << d.year << '-' << d.month << '-' << d.day;
     }
   };
 
-  std::string s = fmt::format("The date is {}", date(2012, 12, 9));
+  template <> struct fmt::formatter<date> : ostream_formatter {};
+
+  std::string s = fmt::format("The date is {}", date{2012, 12, 9});
   // s == "The date is 2012-12-9"
 
-.. doxygenfunction:: print(std::ostream&, string_view, const Args&...)
+.. doxygenfunction:: streamed(const T &)
+
+.. doxygenfunction:: print(std::ostream &os, format_string<T...> fmt, T&&... args)
 
 .. _printf-api:
 
-``printf`` formatting
+``printf`` Formatting
 =====================
 
 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(string_view, const Args&...)
+.. doxygenfunction:: printf(string_view fmt, const T&... args) -> int
 
-.. doxygenfunction:: fprintf(std::FILE *, string_view, const Args&...)
+.. doxygenfunction:: fprintf(std::FILE *f, const S &fmt, const T&... args) -> int
 
-.. doxygenfunction:: fprintf(std::ostream&, string_view, const Args&...)
+.. doxygenfunction:: sprintf(const S&, const T&...)
 
-.. doxygenfunction:: sprintf(string_view, 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``
+========================================
+
+{fmt} implements nearly all of the `C++20 formatting library
+<https://en.cppreference.com/w/cpp/utility/format>`_ with the following
+differences:
+
+* Names are defined in the ``fmt`` namespace instead of ``std`` to avoid
+  collisions with standard library implementations.
+* Width calculation doesn't use grapheme clusterization. The latter has been
+  implemented in a separate branch but hasn't been integrated yet.
+* 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 +1,43 @@
-#!/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']
+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', '8.1.0', '8.1.1', '9.0.0', '9.1.0']
+versions += ['10.0.0', '10.1.0', '10.1.1', '10.1.1', '10.2.0']
 
-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',
-              '6b1c5bb7a1866f15fc328b8716258354b10c1daa',
-              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')
+  # Jinja2 >= 3.1 incompatible with sphinx 3.3.0
+  # See: https://github.com/sphinx-doc/sphinx/issues/10291
+  pip.install('Jinja2<3.1')
+  pip.install('sphinx==3.3.0')
+  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 +46,17 @@ 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}/format.h {0}/ostream.h \
-                          {0}/printf.h {0}/time.h
+      INPUT             = {0}/args.h {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
@@ -86,25 +67,49 @@ 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 \
+                          FMT_USE_ALIAS_TEMPLATES=1 \
+                          FMT_USE_NONTYPE_TEMPLATE_ARGS=1 \
                           FMT_API= \
                           "FMT_BEGIN_NAMESPACE=namespace fmt {{" \
-                          "FMT_END_NAMESPACE=}}"
-      EXCLUDE_SYMBOLS   = fmt::internal::* StringValue write_str
+                          "FMT_END_NAMESPACE=}}" \
+                          "FMT_STRING_ALIAS=1" \
+                          "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'
+  ]
+  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

@@ -1,17 +1,18 @@
 Overview
 ========
 
-**fmt** (formerly cppformat) is an open-source formatting library.
-It can be used as a fast and safe alternative to printf and IOStreams.
+**{fmt}** is an open-source formatting library providing a fast and safe
+alternative to C stdio and C++ iostreams.
 
 .. raw:: html
 
    <div class="panel panel-default">
      <div class="panel-heading">What users say:</div>
      <div class="panel-body">
-       Thanks for creating this library. It’s been a hole in C++ for a long
-       time. I’ve used both boost::format and loki::SPrintf, and neither felt
-       like the right answer. This does.
+       Thanks for creating this library. It’s been a hole in C++ for
+       a long time. I’ve used both <code>boost::format</code> and
+       <code>loki::SPrintf</code>, and neither felt like the right answer.
+       This does.
      </div>
    </div>
 
@@ -20,47 +21,48 @@ It can be used as a fast and safe alternative to printf and IOStreams.
 Format API
 ----------
 
-The replacement-based Format API provides a safe alternative to ``printf``,
-``sprintf`` and friends with comparable or `better performance
-<http://zverovich.net/2013/09/07/integer-to-string-conversion-in-cplusplus.html>`_.
+The format API is similar in spirit to the C ``printf`` family of function but
+is safer, simpler and several times `faster
+<https://www.zverovich.net/2020/06/13/fast-int-to-string-revisited.html>`_
+than common standard library implementations.
 The `format string syntax <syntax.html>`_ is similar to the one used by
-`str.format <http://docs.python.org/3/library/stdtypes.html#str.format>`_
-in Python:
+`str.format <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();
+  fmt::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 file:
+The ``fmt::print`` function performs formatting and writes the result to a stream:
 
 .. code:: c++
 
   fmt::print(stderr, "System error code = {}\n", errno);
 
-The file argument can be omitted in which case the function prints to
-``stdout``:
+If you omit the file argument the function will print to ``stdout``:
 
 .. code:: c++
 
   fmt::print("Don't {}\n", "panic");
 
-The Format API also supports positional arguments useful for localization:
+The format API also supports positional arguments useful for localization:
 
 .. code:: c++
 
   fmt::print("I'd rather be {1} than {0}.", "right", "happy");
 
-Named arguments can be created with ``fmt::arg``. This makes it easier to track 
-what goes where when multiple values are being inserted:
+You can pass named arguments with ``fmt::arg``:
 
 .. code:: c++
 
@@ -72,21 +74,10 @@ an alternative, slightly terser syntax for named arguments:
 
 .. code:: c++
 
+  using namespace fmt::literals;
   fmt::print("Hello, {name}! The answer is {number}. Goodbye, {name}.",
              "name"_a="World", "number"_a=42);
 
-The ``_format`` suffix may be used to format string literals similar to Python:
-
-.. code:: c++
-
-  std::string message = "{0}{1}{0}"_format("abra", "cad"); 
-
-Other than the placement of the format string on the left of the operator, 
-``_format`` is functionally identical to ``fmt::format``. In order to use the 
-literal operators, they must be made visible with the directive 
-``using namespace fmt::literals;``. Note that this brings in only ``_a`` and 
-``_format`` but nothing else from the ``fmt`` namespace.
-
 .. _safety:
 
 Safety
@@ -94,22 +85,23 @@ Safety
 
 The library is fully type safe, automatic memory management prevents buffer
 overflow, errors in format strings are reported using exceptions or at compile
-tim. For example, the code
+time. For example, the code
 
 .. code:: c++
 
   fmt::format("The answer is {:d}", "forty-two");
 
-throws a ``format_error`` exception with description "unknown format code 'd' for
-string", because the argument ``"forty-two"`` is a string while the format code
-``d`` only applies to integers, while
+throws the ``format_error`` exception because the argument ``"forty-two"`` is a
+string while the format code ``d`` only applies to integers.
+
+The code
 
 .. code:: c++
 
-  format(fmt("The answer is {:d}"), "forty-two");
+  format(FMT_STRING("The answer is {:d}"), "forty-two");
 
-reports a compile-time error for the same reason on compilers that support
-relaxed ``constexpr``.
+reports a compile-time error on compilers that support relaxed ``constexpr``.
+See `here <api.html#compile-time-format-string-checks>`_ for details.
 
 The following code
 
@@ -118,21 +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:
+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.
 
-.. 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.
-
-Compact binary code
+Compact Binary Code
 -------------------
 
-The library is designed to produce compact per-call compiled code. For example
+The library produces compact per-call compiled code. For example
 (`godbolt <https://godbolt.org/g/TZU4KF>`_),
 
 .. code:: c++
@@ -153,8 +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
@@ -174,37 +160,39 @@ The library is highly portable and relies only on a small set of C++11 features:
 * decltype
 * trailing return types
 * deleted functions
+* alias templates
 
-These are available since GCC 4.4, Clang 2.9 and MSVC 18.0 (2013). For older
-compilers use fmt `version 4.x
-<https://github.com/fmtlib/fmt/releases/tag/4.1.0>`_ which continues to be
-maintained and only requires C++98.
+These are available in GCC 4.8, Clang 3.4, 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 in this case. For example,
+The output of all formatting functions is consistent across platforms.
+For example,
 
 .. code::
 
   fmt::print("{}", std::numeric_limits<double>::infinity());
 
-always prints ``inf``.
+always prints ``inf`` while the output of ``printf`` is platform-dependent.
 
 .. _ease-of-use:
 
 Ease of Use
 -----------
 
-fmt has a small self-contained code base with the core library consisting of
+{fmt} has a small self-contained code base with the core library consisting of
 just three header files and no external dependencies.
-A permissive BSD `license <https://github.com/fmtlib/fmt#license>`_ allows
+A permissive MIT `license <https://github.com/fmtlib/fmt#license>`_ allows
 using the library both in open-source and commercial projects.
 
+`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.
 
@@ -75,20 +75,20 @@ 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: "<" | ">" | "=" | "^"
+   align: "<" | ">" | "^"
    sign: "+" | "-" | " "
-   width: `integer` | "{" `arg_id` "}"
-   precision: `integer` | "{" `arg_id` "}"
-   type: `int_type` | "a" | "A" | "c" | "e" | "E" | "f" | "F" | "g" | "G" | "p" | "s"
-   int_type: "b" | "B" | "d" | "n" | "o" | "x" | "X"
+   width: `integer` | "{" [`arg_id`] "}"
+   precision: `integer` | "{" [`arg_id`] "}"
+   type: "a" | "A" | "b" | "B" | "c" | "d" | "e" | "E" | "f" | "F" | "g" | "G" |
+       : "o" | "p" | "s" | "x" | "X" | "?"
 
-The *fill* character can be any character other than '{' or '}'.  The presence
-of a fill character is signaled by the character following it, which must be
-one of the alignment options.  If the second character of *format_spec* is not
-a valid alignment option, then it is assumed that both the fill character and
-the alignment option are absent.
+The *fill* character can be any Unicode code point other than ``'{'`` or
+``'}'``. The presence of a fill character is signaled by the character following
+it, which must be one of the alignment options. If the second character of
+*format_spec* is not a valid alignment option, then it is assumed that both the
+fill character and the alignment option are absent.
 
 The meaning of the various alignment options is as follows:
 
@@ -101,11 +101,6 @@ The meaning of the various alignment options is as follows:
 | ``'>'`` | Forces the field to be right-aligned within the          |
 |         | available space (this is the default for numbers).       |
 +---------+----------------------------------------------------------+
-| ``'='`` | Forces the padding to be placed after the sign (if any)  |
-|         | but before the digits.  This is used for printing fields |
-|         | in the form '+000000120'. This alignment option is only  |
-|         | valid for numeric types.                                 |
-+---------+----------------------------------------------------------+
 | ``'^'`` | Forces the field to be centered within the available     |
 |         | space.                                                   |
 +---------+----------------------------------------------------------+
@@ -114,21 +109,21 @@ Note that unless a minimum field width is defined, the field width will always
 be the same size as the data to fill it, so that the alignment option has no
 meaning in this case.
 
-The *sign* option is only valid for number types, and can be one of the
-following:
+The *sign* option is only valid for floating point and signed integer 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
@@ -148,15 +143,17 @@ conversions, trailing zeros are not removed from the result.
 .. ifconfig:: False
 
    The ``','`` option signals the use of a comma for a thousands separator.
-   For a locale aware separator, use the ``'n'`` integer presentation type
+   For a locale aware separator, use the ``'L'`` integer presentation type
    instead.
 
 *width* is a decimal integer defining the minimum field width.  If not
 specified, then the field width will be determined by the content.
 
-Preceding the *width* field by a zero (``'0'``) character enables
-sign-aware zero-padding for numeric types.  This is equivalent to a *fill*
-character of ``'0'`` with an *alignment* type of ``'='``.
+Preceding the *width* field by a zero (``'0'``) character enables sign-aware
+zero-padding for numeric types. It forces the padding to be placed after the
+sign or base (if any) but before the digits. This is used for printing fields in
+the form '+000000120'. This option is only valid for numeric types and it has no
+effect on formatting of infinity and NaN.
 
 The *precision* is a decimal number indicating how many digits should be
 displayed after the decimal point for a floating-point value formatted with
@@ -164,7 +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.
 
@@ -176,6 +177,9 @@ The available string presentation types are:
 | ``'s'`` | String format. This is the default type for strings and  |
 |         | may be omitted.                                          |
 +---------+----------------------------------------------------------+
+| ``'?'`` | Debug format. The string is quoted and special           |
+|         | characters escaped.                                      |
++---------+----------------------------------------------------------+
 | none    | The same as ``'s'``.                                     |
 +---------+----------------------------------------------------------+
 
@@ -187,6 +191,9 @@ The available character presentation types are:
 | ``'c'`` | Character format. This is the default type for           |
 |         | characters and may be omitted.                           |
 +---------+----------------------------------------------------------+
+| ``'?'`` | Debug format. The character is quoted and special        |
+|         | characters escaped.                                      |
++---------+----------------------------------------------------------+
 | none    | The same as ``'c'``.                                     |
 +---------+----------------------------------------------------------+
 
@@ -203,6 +210,8 @@ 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.              |
@@ -217,16 +226,13 @@ The available integer presentation types are:
 |         | ``'#'`` option with this type adds the prefix ``"0X"``   |
 |         | to the output value.                                     |
 +---------+----------------------------------------------------------+
-| ``'n'`` | Number. This is the same as ``'d'``, except that it uses |
-|         | the current locale setting to insert the appropriate     |
-|         | number separator characters.                             |
-+---------+----------------------------------------------------------+
 | none    | The same as ``'d'``.                                     |
 +---------+----------------------------------------------------------+
 
-Integer presentation types can also be used with character and Boolean values.
-Boolean values are formatted using textual representation, either ``true`` or
-``false``, if the presentation type is not specified.
+Integer presentation types can also be used with character and Boolean values
+with the only exception that ``'c'`` cannot be used with `bool`. Boolean values
+are formatted using textual representation, either ``true`` or ``false``, if the
+presentation type is not specified.
 
 The available presentation types for floating-point values are:
 
@@ -244,7 +250,7 @@ The available presentation types for floating-point values are:
 |         | notation using the letter 'e' to indicate the exponent.  |
 +---------+----------------------------------------------------------+
 | ``'E'`` | Exponent notation. Same as ``'e'`` except it uses an     |
-|         | upper-case 'E' as the separator character.               |
+|         | upper-case ``'E'`` as the separator character.           |
 +---------+----------------------------------------------------------+
 | ``'f'`` | Fixed point. Displays the number as a fixed-point        |
 |         | number.                                                  |
@@ -264,11 +270,10 @@ The available presentation types for floating-point values are:
 |         | ``'E'`` if the number gets too large. The                |
 |         | representations of infinity and NaN are uppercased, too. |
 +---------+----------------------------------------------------------+
-| none    | The same as ``'g'``.                                     |
+| none    | Similar to ``'g'``, except that the default precision is |
+|         | as high as needed to represent the particular value.     |
 +---------+----------------------------------------------------------+
 
-Floating-point formatting is locale-dependent.
-
 .. ifconfig:: False
 
    +---------+----------------------------------------------------------+
@@ -301,9 +306,215 @@ The available presentation types for pointers are:
 | none    | The same as ``'p'``.                                     |
 +---------+----------------------------------------------------------+
 
+.. _chrono-specs:
+
+Chrono Format Specifications
+============================
+
+Format specifications for chrono duration and time point types as well as
+``std::tm`` 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*) are:
+
++---------+--------------------------------------------------------------------+
+| Type    | Meaning                                                            |
++=========+====================================================================+
+| ``'a'`` | The abbreviated weekday name, e.g. "Sat". If the value does not    |
+|         | contain a valid weekday, an exception of type ``format_error`` is  |
+|         | thrown.                                                            |
++---------+--------------------------------------------------------------------+
+| ``'A'`` | The full weekday name, e.g. "Saturday". If the value does not      |
+|         | contain a valid weekday, an exception of type ``format_error`` is  |
+|         | thrown.                                                            |
++---------+--------------------------------------------------------------------+
+| ``'b'`` | The abbreviated month name, e.g. "Nov". If the value does not      |
+|         | contain a valid month, an exception of type ``format_error`` is    |
+|         | thrown.                                                            |
++---------+--------------------------------------------------------------------+
+| ``'B'`` | The full month name, e.g. "November". If the value does not        |
+|         | contain a valid month, an exception of type ``format_error`` is    |
+|         | thrown.                                                            |
++---------+--------------------------------------------------------------------+
+| ``'c'`` | The date and time representation, e.g. "Sat Nov 12 22:04:00 1955". |
+|         | The modified command ``%Ec`` produces the locale's alternate date  |
+|         | and time representation.                                           |
++---------+--------------------------------------------------------------------+
+| ``'C'`` | The year divided by 100 using floored division, e.g. "55". If the  |
+|         | result is a single decimal digit, it is prefixed with 0.           |
+|         | The modified command ``%EC`` produces the locale's alternative     |
+|         | representation of the century.                                     |
++---------+--------------------------------------------------------------------+
+| ``'d'`` | The day of month as a decimal number. If the result is a single    |
+|         | decimal digit, it is prefixed with 0. The modified command ``%Od`` |
+|         | produces the locale's alternative representation.                  |
++---------+--------------------------------------------------------------------+
+| ``'D'`` | Equivalent to ``%m/%d/%y``, e.g. "11/12/55".                       |
++---------+--------------------------------------------------------------------+
+| ``'e'`` | The day of month as a decimal number. If the result is a single    |
+|         | decimal digit, it is prefixed with a space. The modified command   |
+|         | ``%Oe`` produces the locale's alternative representation.          |
++---------+--------------------------------------------------------------------+
+| ``'F'`` | Equivalent to ``%Y-%m-%d``, e.g. "1955-11-12".                     |
++---------+--------------------------------------------------------------------+
+| ``'g'`` | The last two decimal digits of the ISO week-based year. If the     |
+|         | result is a single digit it is prefixed by 0.                      |
++---------+--------------------------------------------------------------------+
+| ``'G'`` | The ISO week-based year as a decimal number. If the result is less |
+|         | than four digits it is left-padded with 0 to four digits.          |
++---------+--------------------------------------------------------------------+
+| ``'h'`` | Equivalent to ``%b``, e.g. "Nov".                                  |
++---------+--------------------------------------------------------------------+
+| ``'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.                  |
++---------+--------------------------------------------------------------------+
+| ``'I'`` | The hour (12-hour clock) as a decimal number. If the result is a   |
+|         | single digit, it is prefixed with 0. The modified command ``%OI``  |
+|         | produces the locale's alternative representation.                  |
++---------+--------------------------------------------------------------------+
+| ``'j'`` | If the type being formatted is a specialization of duration, the   |
+|         | decimal number of days without padding. Otherwise, the day of the  |
+|         | year as a decimal number. Jan 1 is 001. If the result is less than |
+|         | three digits, it is left-padded with 0 to three digits.            |
++---------+--------------------------------------------------------------------+
+| ``'m'`` | The month as a decimal number. Jan is 01. If the result is a       |
+|         | single digit, it is prefixed with 0. The modified command ``%Om``  |
+|         | 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.                               |
++---------+--------------------------------------------------------------------+
+| ``'n'`` | A new-line character.                                              |
++---------+--------------------------------------------------------------------+
+| ``'p'`` | The AM/PM designations associated with a 12-hour clock.            |
++---------+--------------------------------------------------------------------+
+| ``'q'`` | The duration's unit suffix.                                        |
++---------+--------------------------------------------------------------------+
+| ``'Q'`` | The duration's numeric value (as if extracted via ``.count()``).   |
++---------+--------------------------------------------------------------------+
+| ``'r'`` | The 12-hour clock time, e.g. "10:04:00 PM".                        |
++---------+--------------------------------------------------------------------+
+| ``'R'`` | Equivalent to ``%H:%M``, e.g. "22:04".                             |
++---------+--------------------------------------------------------------------+
+| ``'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.  |
++---------+--------------------------------------------------------------------+
+| ``'t'`` | A horizontal-tab character.                                        |
++---------+--------------------------------------------------------------------+
+| ``'T'`` | Equivalent to ``%H:%M:%S``.                                        |
++---------+--------------------------------------------------------------------+
+| ``'u'`` | The ISO weekday as a decimal number (1-7), where Monday is 1. The  |
+|         | modified command ``%Ou`` produces the locale's alternative         |
+|         | representation.                                                    |
++---------+--------------------------------------------------------------------+
+| ``'U'`` | The week number of the year as a decimal number. The first Sunday  |
+|         | of the year is the first day of week 01. Days of the same year     |
+|         | prior to that are in week 00. If the result is a single digit, it  |
+|         | is prefixed with 0. The modified command ``%OU`` produces the      |
+|         | locale's alternative representation.                               |
++---------+--------------------------------------------------------------------+
+| ``'V'`` | The ISO week-based week number as a decimal number. If the result  |
+|         | is a single digit, it is prefixed with 0. The modified command     |
+|         | ``%OV`` produces the locale's alternative representation.          |
++---------+--------------------------------------------------------------------+
+| ``'w'`` | The weekday as a decimal number (0-6), where Sunday is 0.          |
+|         | The modified command ``%Ow`` produces the locale's alternative     |
+|         | representation.                                                    |
++---------+--------------------------------------------------------------------+
+| ``'W'`` | The week number of the year as a decimal number. The first Monday  |
+|         | of the year is the first day of week 01. Days of the same year     |
+|         | prior to that are in week 00. If the result is a single digit, it  |
+|         | is prefixed with 0. The modified command ``%OW`` produces the      |
+|         | locale's alternative representation.                               |
++---------+--------------------------------------------------------------------+
+| ``'x'`` | The date representation, e.g. "11/12/55". The modified command     |
+|         | ``%Ex`` produces the locale's alternate date representation.       |
++---------+--------------------------------------------------------------------+
+| ``'X'`` | The time representation, e.g. "10:04:00". The modified command     |
+|         | ``%EX`` produces the locale's alternate time representation.       |
++---------+--------------------------------------------------------------------+
+| ``'y'`` | The last two decimal digits of the year. If the result is a single |
+|         | digit it is prefixed by 0. The modified command ``%Oy`` produces   |
+|         | the locale's alternative representation. The modified command      |
+|         | ``%Ey`` produces the locale's alternative representation of offset |
+|         | from ``%EC`` (year only).                                          |
++---------+--------------------------------------------------------------------+
+| ``'Y'`` | The year as a decimal number. If the result is less than four      |
+|         | digits it is left-padded with 0 to four digits. The modified       |
+|         | command ``%EY`` produces the locale's alternative full year        |
+|         | representation.                                                    |
++---------+--------------------------------------------------------------------+
+| ``'z'`` | The offset from UTC in the ISO 8601:2004 format. For example -0430 |
+|         | refers to 4 hours 30 minutes behind UTC. If the offset is zero,    |
+|         | +0000 is used. The modified commands ``%Ez`` and ``%Oz`` insert a  |
+|         | ``:`` between the hours and minutes: -04:30. If the offset         |
+|         | information is not available, an exception of type                 |
+|         | ``format_error`` is thrown.                                        |
++---------+--------------------------------------------------------------------+
+| ``'Z'`` | The time zone abbreviation. If the time zone abbreviation is not   |
+|         | available, an exception of type ``format_error`` is thrown.        |
++---------+--------------------------------------------------------------------+
+| ``'%'`` | A % character.                                                     |
++---------+--------------------------------------------------------------------+
+
+Specifiers that have a calendaric component such as ``'d'`` (the day of month)
+are valid only for ``std::tm`` and time points but not durations.
+
+.. range-specs:
+
+Range Format Specifications
+===========================
+
+Format specifications for range types have the following syntax:
+
+.. productionlist:: sf
+   range_format_spec: [":" [`underlying_spec`]]
+
+The `underlying_spec` is parsed based on the formatter of the range's
+reference type.
+
+By default, a range of characters or strings is printed escaped and quoted. But
+if any `underlying_spec` is provided (even if it is empty), then the characters
+or strings are printed according to the provided specification.
+
+Examples::
+
+  fmt::format("{}", std::vector{10, 20, 30});
+  // Result: [10, 20, 30]
+  fmt::format("{::#x}", std::vector{10, 20, 30});
+  // Result: [0xa, 0x14, 0x1e]
+  fmt::format("{}", vector{'h', 'e', 'l', 'l', 'o'});
+  // Result: ['h', 'e', 'l', 'l', 'o']
+  fmt::format("{::}", vector{'h', 'e', 'l', 'l', 'o'});
+  // Result: [h, e, l, l, o]
+  fmt::format("{::d}", vector{'h', 'e', 'l', 'l', 'o'});
+  // Result: [104, 101, 108, 108, 111]
+
 .. _formatexamples:
 
-Format examples
+Format Examples
 ===============
 
 This section contains examples of the format syntax and comparison with
@@ -318,72 +529,94 @@ following examples.
 
 Accessing arguments by position::
 
-   format("{0}, {1}, {2}", 'a', 'b', 'c');
+   fmt::format("{0}, {1}, {2}", 'a', 'b', 'c');
    // Result: "a, b, c"
-   format("{}, {}, {}", 'a', 'b', 'c');
+   fmt::format("{}, {}, {}", 'a', 'b', 'c');
    // Result: "a, b, c"
-   format("{2}, {1}, {0}", 'a', 'b', 'c');
+   fmt::format("{2}, {1}, {0}", 'a', 'b', 'c');
    // Result: "c, b, a"
-   format("{0}{1}{0}", "abra", "cad");  // arguments' indices can be repeated
+   fmt::format("{0}{1}{0}", "abra", "cad");  // arguments' indices can be repeated
    // Result: "abracadabra"
 
 Aligning the text and specifying a width::
 
-   format("{:<30}", "left aligned");
+   fmt::format("{:<30}", "left aligned");
    // Result: "left aligned                  "
-   format("{:>30}", "right aligned");
+   fmt::format("{:>30}", "right aligned");
    // Result: "                 right aligned"
-   format("{:^30}", "centered");
+   fmt::format("{:^30}", "centered");
    // Result: "           centered           "
-   format("{:*^30}", "centered");  // use '*' as a fill char
+   fmt::format("{:*^30}", "centered");  // use '*' as a fill char
    // Result: "***********centered***********"
 
 Dynamic width::
 
-   format("{:<{}}", "left aligned", 30);
+   fmt::format("{:<{}}", "left aligned", 30);
    // Result: "left aligned                  "
 
 Dynamic precision::
 
-   format("{:.{}f}", 3.14, 1);
+   fmt::format("{:.{}f}", 3.14, 1);
    // Result: "3.1"
 
 Replacing ``%+f``, ``%-f``, and ``% f`` and specifying a sign::
 
-   format("{:+f}; {:+f}", 3.14, -3.14);  // show it always
+   fmt::format("{:+f}; {:+f}", 3.14, -3.14);  // show it always
    // Result: "+3.140000; -3.140000"
-   format("{: f}; {: f}", 3.14, -3.14);  // show a space for positive numbers
+   fmt::format("{: f}; {: f}", 3.14, -3.14);  // show a space for positive numbers
    // Result: " 3.140000; -3.140000"
-   format("{:-f}; {:-f}", 3.14, -3.14);  // show only the minus -- same as '{:f}; {:f}'
+   fmt::format("{:-f}; {:-f}", 3.14, -3.14);  // show only the minus -- same as '{:f}; {:f}'
    // Result: "3.140000; -3.140000"
 
 Replacing ``%x`` and ``%o`` and converting the value to different bases::
 
-   format("int: {0:d};  hex: {0:x};  oct: {0:o}; bin: {0:b}", 42);
+   fmt::format("int: {0:d};  hex: {0:x};  oct: {0:o}; bin: {0:b}", 42);
    // Result: "int: 42;  hex: 2a;  oct: 52; bin: 101010"
    // with 0x or 0 or 0b as prefix:
-   format("int: {0:d};  hex: {0:#x};  oct: {0:#o};  bin: {0:#b}", 42);
+   fmt::format("int: {0:d};  hex: {0:#x};  oct: {0:#o};  bin: {0:#b}", 42);
    // Result: "int: 42;  hex: 0x2a;  oct: 052;  bin: 0b101010"
 
 Padded hex byte with prefix and always prints both hex characters::
 
-   format("{:#04x}", 0);
+   fmt::format("{:#04x}", 0);
    // Result: "0x00"
 
+Box drawing using Unicode fill::
+
+   fmt::print(
+     "┌{0:─^{2}}┐\n"
+     "│{1: ^{2}}│\n"
+     "└{0:─^{2}}┘\n", "", "Hello, world!", 20);
+
+prints::
+
+   ┌────────────────────┐
+   │   Hello, world!    │
+   └────────────────────┘
+
+Using type-specific formatting::
+
+   #include <fmt/chrono.h>
+
+   auto t = tm();
+   t.tm_year = 2010 - 1900;
+   t.tm_mon = 7;
+   t.tm_mday = 4;
+   t.tm_hour = 12;
+   t.tm_min = 15;
+   t.tm_sec = 58;
+   fmt::print("{:%Y-%m-%d %H:%M:%S}", t);
+   // Prints: 2010-08-04 12:15:58
+
+Using the comma as a thousands separator::
+
+   #include <fmt/format.h>
+
+   auto s = fmt::format(std::locale("en_US.UTF-8"), "{:L}", 1234567890);
+   // s == "1,234,567,890"
+
 .. ifconfig:: False
 
-   Using the comma as a thousands separator::
-
-      format("{:,}", 1234567890);
-      '1,234,567,890'
-
-   Using type-specific formatting::
-
-      >>> import datetime
-      >>> d = datetime.datetime(2010, 7, 4, 12, 15, 58)
-      Format("{:%Y-%m-%d %H:%M:%S}") << d)
-      '2010-07-04 12:15:58'
-
    Nesting arguments and more complex examples::
 
       >>> for align, text in zip('<^>', ['left', 'center', 'right']):
@@ -412,4 +645,3 @@ Padded hex byte with prefix and always prints both hex characters::
           9     9    11  1001
          10     A    12  1010
          11     B    13  1011
-

doc/usage.rst

@@ -2,26 +2,20 @@
 Usage
 *****
 
-To use the fmt library, add :file:`format.h` and :file:`format.cc` from
-a `release archive <https://github.com/fmtlib/fmt/releases/latest>`_
-or the `Git repository <https://github.com/fmtlib/fmt>`_ to your project.
+To use the {fmt} library, add :file:`fmt/core.h`, :file:`fmt/format.h`,
+:file:`fmt/format-inl.h`, :file:`src/format.cc` and optionally other headers
+from a `release archive <https://github.com/fmtlib/fmt/releases/latest>`_ or
+the `Git repository <https://github.com/fmtlib/fmt>`_ to your project.
 Alternatively, you can :ref:`build the library with CMake <building>`.
 
-If you are using Visual C++ with precompiled headers, you might need to add
-the line ::
-
-   #include "stdafx.h"
-
-before other includes in :file:`format.cc`.
-
 .. _building:
 
-Building the library
+Building the Library
 ====================
 
 The included `CMake build script`__ can be used to build the fmt
 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
 
@@ -31,7 +25,7 @@ workflow starts with::
 
   mkdir build          # Create a directory to hold the build output.
   cd build
-  cmake <path/to/fmt>  # Generate native build scripts.
+  cmake ..  # Generate native build scripts.
 
 where :file:`{<path/to/fmt>}` is a path to the ``fmt`` repository.
 
@@ -45,7 +39,7 @@ You can control generation of the make ``test`` target with the ``FMT_TEST``
 CMake option. This can be useful if you include fmt as a subdirectory in
 your project but don't want to add fmt's tests to your ``test`` target.
 
-If you use Windows and have Visual Studio installed, a :file:`FORMAT.sln`
+If you use Windows and have Visual Studio installed, a :file:`FMT.sln`
 file and several :file:`.vcproj` files will be created. You can then build them
 using Visual Studio or msbuild.
 
@@ -56,10 +50,24 @@ 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
 
-Header-only usage with CMake
-============================
+
+To build a `static library` with position independent code (required if the main
+consumer of the fmt library is a shared library i.e. a Python extension) set the
+``CMAKE_POSITION_INDEPENDENT_CODE`` CMake variable to ``TRUE``::
+
+  cmake -DCMAKE_POSITION_INDEPENDENT_CODE=TRUE ...
+
+
+Installing the Library
+======================
+
+After building the library you can install it on a Unix-like system by running
+:command:`sudo make install`.
+
+Usage with CMake
+================
 
 You can add the ``fmt`` library directory into your project and include it in
 your ``CMakeLists.txt`` file::
@@ -74,11 +82,97 @@ or
 
 to exclude it from ``make``, ``make all``, or ``cmake --build .``.
 
-Settting up your target to use a header-only version of ``fmt`` is equaly easy::
+You can detect and use an installed version of {fmt} as follows::
 
-   target_link_libraries(<your-target> PRIVATE fmt-header-only)
+   find_package(fmt)
+   target_link_libraries(<your-target> fmt::fmt)
 
-Building the documentation
+Setting up your target to use a header-only version of ``fmt`` is equally easy::
+
+   target_link_libraries(<your-target> PRIVATE fmt::fmt-header-only)
+
+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>`_.
+
+Usage with Meson
+================
+
+`Meson's WrapDB <https://mesonbuild.com/Wrapdb-projects.html>` includes a ``fmt``
+package, which repackages fmt to be built by Meson as a subproject.
+
+**Usage:**
+
+- Install the ``fmt`` subproject from the WrapDB by running::
+
+    meson wrap install fmt
+
+  from the root of your project.
+
+- In your project's ``meson.build`` file, add an entry for the new subproject::
+
+    fmt = subproject('fmt')
+    fmt_dep = fmt.get_variable('fmt_dep')
+
+- Include the new dependency object to link with fmt::
+
+    my_build_target = executable('name', 'src/main.cc', dependencies: [fmt_dep])
+
+**Options:**
+
+If desired, ``fmt`` may be built as a static library, or as a header-only
+library.
+
+For a static build, use the following subproject definition::
+
+  fmt = subproject('fmt', default_options: 'default_library=static')
+  fmt_dep = fmt.get_variable('fmt_dep')
+
+For the header-only version, use::
+
+  fmt = subproject('fmt')
+  fmt_dep = fmt.get_variable('fmt_header_only_dep')
+
+Building the Documentation
 ==========================
 
 To build the documentation you need the following software installed on your
@@ -98,7 +192,45 @@ the previous section. Then compile the ``doc`` target/project, for example::
   make doc
 
 This will generate the HTML documentation in ``doc/html``.
-  
+
+Conda
+=====
+
+fmt can be installed on Linux, macOS and Windows with
+`Conda <https://docs.conda.io/en/latest/>`__, using its
+`conda-forge <https://conda-forge.org>`__
+`package <https://github.com/conda-forge/fmt-feedstock>`__, as follows::
+
+  conda install -c conda-forge fmt
+
+Vcpkg
+=====
+
+You can download and install fmt using the `vcpkg
+<https://github.com/Microsoft/vcpkg>`__ dependency manager::
+
+  git clone https://github.com/Microsoft/vcpkg.git
+  cd vcpkg
+  ./bootstrap-vcpkg.sh
+  ./vcpkg integrate install
+  ./vcpkg install fmt
+
+The fmt port in vcpkg is kept up to date by Microsoft team members and community
+contributors. If the version is out of date, please `create an issue or pull
+request <https://github.com/Microsoft/vcpkg>`__ on the vcpkg repository.
+
+LHelper
+=======
+
+You can download and install fmt using
+`lhelper <https://github.com/franko/lhelper>`__ dependency manager::
+
+  lhelper activate <some-environment>
+  lhelper install fmt
+
+All the recipes for lhelper are kept in the
+`lhelper's recipe <https://github.com/franko/lhelper-recipes>`__ repository.
+
 Android NDK
 ===========
 
@@ -108,11 +240,11 @@ 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 +1,235 @@
+// Formatting library for C++ - dynamic argument lists
+//
+// 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> auto unwrap(const T& v) -> const T& { return v; }
+template <typename T>
+auto unwrap(const std::reference_wrapper<T>& v) -> const T& {
+  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> auto push(const Arg& arg) -> const T& {
+    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<
+      std::is_convertible<T, std::basic_string<char_type>>::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>;
+
+  auto get_types() const -> unsigned long long {
+    return detail::is_unpacked_bit | data_.size() |
+           (named_info_.empty()
+                ? 0ULL
+                : static_cast<unsigned long long>(detail::has_named_args_bit));
+  }
+
+  auto data() const -> const basic_format_arg<Context>* {
+    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

@@ -0,0 +1,643 @@
+// Formatting library for C++ - color support
+//
+// Copyright (c) 2018 - present, Victor Zverovich and fmt contributors
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_COLOR_H_
+#define FMT_COLOR_H_
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+FMT_BEGIN_EXPORT
+
+enum class color : uint32_t {
+  alice_blue = 0xF0F8FF,               // rgb(240,248,255)
+  antique_white = 0xFAEBD7,            // rgb(250,235,215)
+  aqua = 0x00FFFF,                     // rgb(0,255,255)
+  aquamarine = 0x7FFFD4,               // rgb(127,255,212)
+  azure = 0xF0FFFF,                    // rgb(240,255,255)
+  beige = 0xF5F5DC,                    // rgb(245,245,220)
+  bisque = 0xFFE4C4,                   // rgb(255,228,196)
+  black = 0x000000,                    // rgb(0,0,0)
+  blanched_almond = 0xFFEBCD,          // rgb(255,235,205)
+  blue = 0x0000FF,                     // rgb(0,0,255)
+  blue_violet = 0x8A2BE2,              // rgb(138,43,226)
+  brown = 0xA52A2A,                    // rgb(165,42,42)
+  burly_wood = 0xDEB887,               // rgb(222,184,135)
+  cadet_blue = 0x5F9EA0,               // rgb(95,158,160)
+  chartreuse = 0x7FFF00,               // rgb(127,255,0)
+  chocolate = 0xD2691E,                // rgb(210,105,30)
+  coral = 0xFF7F50,                    // rgb(255,127,80)
+  cornflower_blue = 0x6495ED,          // rgb(100,149,237)
+  cornsilk = 0xFFF8DC,                 // rgb(255,248,220)
+  crimson = 0xDC143C,                  // rgb(220,20,60)
+  cyan = 0x00FFFF,                     // rgb(0,255,255)
+  dark_blue = 0x00008B,                // rgb(0,0,139)
+  dark_cyan = 0x008B8B,                // rgb(0,139,139)
+  dark_golden_rod = 0xB8860B,          // rgb(184,134,11)
+  dark_gray = 0xA9A9A9,                // rgb(169,169,169)
+  dark_green = 0x006400,               // rgb(0,100,0)
+  dark_khaki = 0xBDB76B,               // rgb(189,183,107)
+  dark_magenta = 0x8B008B,             // rgb(139,0,139)
+  dark_olive_green = 0x556B2F,         // rgb(85,107,47)
+  dark_orange = 0xFF8C00,              // rgb(255,140,0)
+  dark_orchid = 0x9932CC,              // rgb(153,50,204)
+  dark_red = 0x8B0000,                 // rgb(139,0,0)
+  dark_salmon = 0xE9967A,              // rgb(233,150,122)
+  dark_sea_green = 0x8FBC8F,           // rgb(143,188,143)
+  dark_slate_blue = 0x483D8B,          // rgb(72,61,139)
+  dark_slate_gray = 0x2F4F4F,          // rgb(47,79,79)
+  dark_turquoise = 0x00CED1,           // rgb(0,206,209)
+  dark_violet = 0x9400D3,              // rgb(148,0,211)
+  deep_pink = 0xFF1493,                // rgb(255,20,147)
+  deep_sky_blue = 0x00BFFF,            // rgb(0,191,255)
+  dim_gray = 0x696969,                 // rgb(105,105,105)
+  dodger_blue = 0x1E90FF,              // rgb(30,144,255)
+  fire_brick = 0xB22222,               // rgb(178,34,34)
+  floral_white = 0xFFFAF0,             // rgb(255,250,240)
+  forest_green = 0x228B22,             // rgb(34,139,34)
+  fuchsia = 0xFF00FF,                  // rgb(255,0,255)
+  gainsboro = 0xDCDCDC,                // rgb(220,220,220)
+  ghost_white = 0xF8F8FF,              // rgb(248,248,255)
+  gold = 0xFFD700,                     // rgb(255,215,0)
+  golden_rod = 0xDAA520,               // rgb(218,165,32)
+  gray = 0x808080,                     // rgb(128,128,128)
+  green = 0x008000,                    // rgb(0,128,0)
+  green_yellow = 0xADFF2F,             // rgb(173,255,47)
+  honey_dew = 0xF0FFF0,                // rgb(240,255,240)
+  hot_pink = 0xFF69B4,                 // rgb(255,105,180)
+  indian_red = 0xCD5C5C,               // rgb(205,92,92)
+  indigo = 0x4B0082,                   // rgb(75,0,130)
+  ivory = 0xFFFFF0,                    // rgb(255,255,240)
+  khaki = 0xF0E68C,                    // rgb(240,230,140)
+  lavender = 0xE6E6FA,                 // rgb(230,230,250)
+  lavender_blush = 0xFFF0F5,           // rgb(255,240,245)
+  lawn_green = 0x7CFC00,               // rgb(124,252,0)
+  lemon_chiffon = 0xFFFACD,            // rgb(255,250,205)
+  light_blue = 0xADD8E6,               // rgb(173,216,230)
+  light_coral = 0xF08080,              // rgb(240,128,128)
+  light_cyan = 0xE0FFFF,               // rgb(224,255,255)
+  light_golden_rod_yellow = 0xFAFAD2,  // rgb(250,250,210)
+  light_gray = 0xD3D3D3,               // rgb(211,211,211)
+  light_green = 0x90EE90,              // rgb(144,238,144)
+  light_pink = 0xFFB6C1,               // rgb(255,182,193)
+  light_salmon = 0xFFA07A,             // rgb(255,160,122)
+  light_sea_green = 0x20B2AA,          // rgb(32,178,170)
+  light_sky_blue = 0x87CEFA,           // rgb(135,206,250)
+  light_slate_gray = 0x778899,         // rgb(119,136,153)
+  light_steel_blue = 0xB0C4DE,         // rgb(176,196,222)
+  light_yellow = 0xFFFFE0,             // rgb(255,255,224)
+  lime = 0x00FF00,                     // rgb(0,255,0)
+  lime_green = 0x32CD32,               // rgb(50,205,50)
+  linen = 0xFAF0E6,                    // rgb(250,240,230)
+  magenta = 0xFF00FF,                  // rgb(255,0,255)
+  maroon = 0x800000,                   // rgb(128,0,0)
+  medium_aquamarine = 0x66CDAA,        // rgb(102,205,170)
+  medium_blue = 0x0000CD,              // rgb(0,0,205)
+  medium_orchid = 0xBA55D3,            // rgb(186,85,211)
+  medium_purple = 0x9370DB,            // rgb(147,112,219)
+  medium_sea_green = 0x3CB371,         // rgb(60,179,113)
+  medium_slate_blue = 0x7B68EE,        // rgb(123,104,238)
+  medium_spring_green = 0x00FA9A,      // rgb(0,250,154)
+  medium_turquoise = 0x48D1CC,         // rgb(72,209,204)
+  medium_violet_red = 0xC71585,        // rgb(199,21,133)
+  midnight_blue = 0x191970,            // rgb(25,25,112)
+  mint_cream = 0xF5FFFA,               // rgb(245,255,250)
+  misty_rose = 0xFFE4E1,               // rgb(255,228,225)
+  moccasin = 0xFFE4B5,                 // rgb(255,228,181)
+  navajo_white = 0xFFDEAD,             // rgb(255,222,173)
+  navy = 0x000080,                     // rgb(0,0,128)
+  old_lace = 0xFDF5E6,                 // rgb(253,245,230)
+  olive = 0x808000,                    // rgb(128,128,0)
+  olive_drab = 0x6B8E23,               // rgb(107,142,35)
+  orange = 0xFFA500,                   // rgb(255,165,0)
+  orange_red = 0xFF4500,               // rgb(255,69,0)
+  orchid = 0xDA70D6,                   // rgb(218,112,214)
+  pale_golden_rod = 0xEEE8AA,          // rgb(238,232,170)
+  pale_green = 0x98FB98,               // rgb(152,251,152)
+  pale_turquoise = 0xAFEEEE,           // rgb(175,238,238)
+  pale_violet_red = 0xDB7093,          // rgb(219,112,147)
+  papaya_whip = 0xFFEFD5,              // rgb(255,239,213)
+  peach_puff = 0xFFDAB9,               // rgb(255,218,185)
+  peru = 0xCD853F,                     // rgb(205,133,63)
+  pink = 0xFFC0CB,                     // rgb(255,192,203)
+  plum = 0xDDA0DD,                     // rgb(221,160,221)
+  powder_blue = 0xB0E0E6,              // rgb(176,224,230)
+  purple = 0x800080,                   // rgb(128,0,128)
+  rebecca_purple = 0x663399,           // rgb(102,51,153)
+  red = 0xFF0000,                      // rgb(255,0,0)
+  rosy_brown = 0xBC8F8F,               // rgb(188,143,143)
+  royal_blue = 0x4169E1,               // rgb(65,105,225)
+  saddle_brown = 0x8B4513,             // rgb(139,69,19)
+  salmon = 0xFA8072,                   // rgb(250,128,114)
+  sandy_brown = 0xF4A460,              // rgb(244,164,96)
+  sea_green = 0x2E8B57,                // rgb(46,139,87)
+  sea_shell = 0xFFF5EE,                // rgb(255,245,238)
+  sienna = 0xA0522D,                   // rgb(160,82,45)
+  silver = 0xC0C0C0,                   // rgb(192,192,192)
+  sky_blue = 0x87CEEB,                 // rgb(135,206,235)
+  slate_blue = 0x6A5ACD,               // rgb(106,90,205)
+  slate_gray = 0x708090,               // rgb(112,128,144)
+  snow = 0xFFFAFA,                     // rgb(255,250,250)
+  spring_green = 0x00FF7F,             // rgb(0,255,127)
+  steel_blue = 0x4682B4,               // rgb(70,130,180)
+  tan = 0xD2B48C,                      // rgb(210,180,140)
+  teal = 0x008080,                     // rgb(0,128,128)
+  thistle = 0xD8BFD8,                  // rgb(216,191,216)
+  tomato = 0xFF6347,                   // rgb(255,99,71)
+  turquoise = 0x40E0D0,                // rgb(64,224,208)
+  violet = 0xEE82EE,                   // rgb(238,130,238)
+  wheat = 0xF5DEB3,                    // rgb(245,222,179)
+  white = 0xFFFFFF,                    // rgb(255,255,255)
+  white_smoke = 0xF5F5F5,              // rgb(245,245,245)
+  yellow = 0xFFFF00,                   // rgb(255,255,0)
+  yellow_green = 0x9ACD32              // rgb(154,205,50)
+};                                     // enum class color
+
+enum class terminal_color : uint8_t {
+  black = 30,
+  red,
+  green,
+  yellow,
+  blue,
+  magenta,
+  cyan,
+  white,
+  bright_black = 90,
+  bright_red,
+  bright_green,
+  bright_yellow,
+  bright_blue,
+  bright_magenta,
+  bright_cyan,
+  bright_white
+};
+
+enum class emphasis : uint8_t {
+  bold = 1,
+  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.
+// Using the name "rgb" makes some editors show the color in a tooltip.
+struct rgb {
+  FMT_CONSTEXPR rgb() : r(0), g(0), b(0) {}
+  FMT_CONSTEXPR rgb(uint8_t r_, uint8_t g_, uint8_t b_) : r(r_), g(g_), b(b_) {}
+  FMT_CONSTEXPR rgb(uint32_t hex)
+      : r((hex >> 16) & 0xFF), g((hex >> 8) & 0xFF), b(hex & 0xFF) {}
+  FMT_CONSTEXPR rgb(color hex)
+      : r((uint32_t(hex) >> 16) & 0xFF),
+        g((uint32_t(hex) >> 8) & 0xFF),
+        b(uint32_t(hex) & 0xFF) {}
+  uint8_t r;
+  uint8_t g;
+  uint8_t b;
+};
+
+namespace detail {
+
+// color is a struct of either a rgb color or a terminal color.
+struct color_type {
+  FMT_CONSTEXPR color_type() noexcept : is_rgb(), value{} {}
+  FMT_CONSTEXPR color_type(color rgb_color) noexcept : is_rgb(true), value{} {
+    value.rgb_color = static_cast<uint32_t>(rgb_color);
+  }
+  FMT_CONSTEXPR color_type(rgb rgb_color) noexcept : is_rgb(true), value{} {
+    value.rgb_color = (static_cast<uint32_t>(rgb_color.r) << 16) |
+                      (static_cast<uint32_t>(rgb_color.g) << 8) | rgb_color.b;
+  }
+  FMT_CONSTEXPR color_type(terminal_color term_color) noexcept
+      : is_rgb(), value{} {
+    value.term_color = static_cast<uint8_t>(term_color);
+  }
+  bool is_rgb;
+  union color_union {
+    uint8_t term_color;
+    uint32_t rgb_color;
+  } value;
+};
+}  // namespace detail
+
+/** A text style consisting of foreground and background colors and emphasis. */
+class text_style {
+ public:
+  FMT_CONSTEXPR text_style(emphasis em = emphasis()) noexcept
+      : set_foreground_color(), set_background_color(), ems(em) {}
+
+  FMT_CONSTEXPR auto operator|=(const text_style& rhs) -> text_style& {
+    if (!set_foreground_color) {
+      set_foreground_color = rhs.set_foreground_color;
+      foreground_color = rhs.foreground_color;
+    } else if (rhs.set_foreground_color) {
+      if (!foreground_color.is_rgb || !rhs.foreground_color.is_rgb)
+        FMT_THROW(format_error("can't OR a terminal color"));
+      foreground_color.value.rgb_color |= rhs.foreground_color.value.rgb_color;
+    }
+
+    if (!set_background_color) {
+      set_background_color = rhs.set_background_color;
+      background_color = rhs.background_color;
+    } else if (rhs.set_background_color) {
+      if (!background_color.is_rgb || !rhs.background_color.is_rgb)
+        FMT_THROW(format_error("can't OR a terminal color"));
+      background_color.value.rgb_color |= rhs.background_color.value.rgb_color;
+    }
+
+    ems = static_cast<emphasis>(static_cast<uint8_t>(ems) |
+                                static_cast<uint8_t>(rhs.ems));
+    return *this;
+  }
+
+  friend FMT_CONSTEXPR auto operator|(text_style lhs, const text_style& rhs)
+      -> text_style {
+    return lhs |= rhs;
+  }
+
+  FMT_CONSTEXPR auto has_foreground() const noexcept -> bool {
+    return set_foreground_color;
+  }
+  FMT_CONSTEXPR auto has_background() const noexcept -> bool {
+    return set_background_color;
+  }
+  FMT_CONSTEXPR auto has_emphasis() const noexcept -> bool {
+    return static_cast<uint8_t>(ems) != 0;
+  }
+  FMT_CONSTEXPR auto get_foreground() const noexcept -> detail::color_type {
+    FMT_ASSERT(has_foreground(), "no foreground specified for this style");
+    return foreground_color;
+  }
+  FMT_CONSTEXPR auto get_background() const noexcept -> detail::color_type {
+    FMT_ASSERT(has_background(), "no background specified for this style");
+    return background_color;
+  }
+  FMT_CONSTEXPR auto get_emphasis() const noexcept -> emphasis {
+    FMT_ASSERT(has_emphasis(), "no emphasis specified for this style");
+    return ems;
+  }
+
+ private:
+  FMT_CONSTEXPR text_style(bool is_foreground,
+                           detail::color_type text_color) noexcept
+      : set_foreground_color(), set_background_color(), ems() {
+    if (is_foreground) {
+      foreground_color = text_color;
+      set_foreground_color = true;
+    } else {
+      background_color = text_color;
+      set_background_color = true;
+    }
+  }
+
+  friend FMT_CONSTEXPR auto fg(detail::color_type foreground) noexcept
+      -> text_style;
+
+  friend FMT_CONSTEXPR auto bg(detail::color_type background) noexcept
+      -> text_style;
+
+  detail::color_type foreground_color;
+  detail::color_type background_color;
+  bool set_foreground_color;
+  bool set_background_color;
+  emphasis ems;
+};
+
+/** Creates a text style from the foreground (text) color. */
+FMT_CONSTEXPR inline auto fg(detail::color_type foreground) noexcept
+    -> text_style {
+  return text_style(true, foreground);
+}
+
+/** Creates a text style from the background color. */
+FMT_CONSTEXPR inline auto bg(detail::color_type background) noexcept
+    -> text_style {
+  return text_style(false, background);
+}
+
+FMT_CONSTEXPR inline auto operator|(emphasis lhs, emphasis rhs) noexcept
+    -> text_style {
+  return text_style(lhs) | rhs;
+}
+
+namespace detail {
+
+template <typename Char> struct ansi_color_escape {
+  FMT_CONSTEXPR ansi_color_escape(detail::color_type text_color,
+                                  const char* esc) noexcept {
+    // If we have a terminal color, we need to output another escape code
+    // sequence.
+    if (!text_color.is_rgb) {
+      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.
+      if (is_background) value += 10u;
+
+      size_t index = 0;
+      buffer[index++] = static_cast<Char>('\x1b');
+      buffer[index++] = static_cast<Char>('[');
+
+      if (value >= 100u) {
+        buffer[index++] = static_cast<Char>('1');
+        value %= 100u;
+      }
+      buffer[index++] = static_cast<Char>('0' + value / 10u);
+      buffer[index++] = static_cast<Char>('0' + value % 10u);
+
+      buffer[index++] = static_cast<Char>('m');
+      buffer[index++] = static_cast<Char>('\0');
+      return;
+    }
+
+    for (int i = 0; i < 7; i++) {
+      buffer[i] = static_cast<Char>(esc[i]);
+    }
+    rgb color(text_color.value.rgb_color);
+    to_esc(color.r, buffer + 7, ';');
+    to_esc(color.g, buffer + 11, ';');
+    to_esc(color.b, buffer + 15, 'm');
+    buffer[19] = static_cast<Char>(0);
+  }
+  FMT_CONSTEXPR ansi_color_escape(emphasis em) noexcept {
+    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 (size_t i = 0; i < num_emphases; ++i) {
+      if (!em_codes[i]) continue;
+      buffer[index++] = static_cast<Char>('\x1b');
+      buffer[index++] = static_cast<Char>('[');
+      buffer[index++] = static_cast<Char>('0' + em_codes[i]);
+      buffer[index++] = static_cast<Char>('m');
+    }
+    buffer[index++] = static_cast<Char>(0);
+  }
+  FMT_CONSTEXPR operator const Char*() const noexcept { return buffer; }
+
+  FMT_CONSTEXPR auto begin() const noexcept -> const Char* { return buffer; }
+  FMT_CONSTEXPR_CHAR_TRAITS auto end() const noexcept -> const Char* {
+    return buffer + std::char_traits<Char>::length(buffer);
+  }
+
+ private:
+  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) noexcept {
+    out[0] = static_cast<Char>('0' + c / 100);
+    out[1] = static_cast<Char>('0' + c / 10 % 10);
+    out[2] = static_cast<Char>('0' + c % 10);
+    out[3] = static_cast<Char>(delimiter);
+  }
+  static FMT_CONSTEXPR auto has_emphasis(emphasis em, emphasis mask) noexcept
+      -> bool {
+    return static_cast<uint8_t>(em) & static_cast<uint8_t>(mask);
+  }
+};
+
+template <typename Char>
+FMT_CONSTEXPR auto make_foreground_color(detail::color_type foreground) noexcept
+    -> ansi_color_escape<Char> {
+  return ansi_color_escape<Char>(foreground, "\x1b[38;2;");
+}
+
+template <typename Char>
+FMT_CONSTEXPR auto make_background_color(detail::color_type background) noexcept
+    -> ansi_color_escape<Char> {
+  return ansi_color_escape<Char>(background, "\x1b[48;2;");
+}
+
+template <typename Char>
+FMT_CONSTEXPR auto make_emphasis(emphasis em) noexcept
+    -> ansi_color_escape<Char> {
+  return ansi_color_escape<Char>(em);
+}
+
+template <typename Char> inline void reset_color(buffer<Char>& buffer) {
+  auto reset_color = string_view("\x1b[0m");
+  buffer.append(reset_color.begin(), reset_color.end());
+}
+
+template <typename T> struct styled_arg : detail::view {
+  const T& value;
+  text_style style;
+  styled_arg(const T& v, text_style s) : value(v), style(s) {}
+};
+
+template <typename Char>
+void vformat_to(buffer<Char>& buf, const text_style& ts,
+                basic_string_view<Char> format_str,
+                basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  bool has_style = false;
+  if (ts.has_emphasis()) {
+    has_style = true;
+    auto emphasis = detail::make_emphasis<Char>(ts.get_emphasis());
+    buf.append(emphasis.begin(), emphasis.end());
+  }
+  if (ts.has_foreground()) {
+    has_style = true;
+    auto foreground = detail::make_foreground_color<Char>(ts.get_foreground());
+    buf.append(foreground.begin(), foreground.end());
+  }
+  if (ts.has_background()) {
+    has_style = true;
+    auto background = detail::make_background_color<Char>(ts.get_background());
+    buf.append(background.begin(), background.end());
+  }
+  detail::vformat_to(buf, format_str, args, {});
+  if (has_style) detail::reset_color<Char>(buf);
+}
+
+}  // namespace detail
+
+inline void vprint(std::FILE* f, const text_style& ts, string_view fmt,
+                   format_args args) {
+  // Legacy wide streams are not supported.
+  auto buf = memory_buffer();
+  detail::vformat_to(buf, ts, fmt, args);
+  if (detail::is_utf8()) {
+    detail::print(f, string_view(buf.begin(), buf.size()));
+    return;
+  }
+  buf.push_back('\0');
+  int result = std::fputs(buf.data(), f);
+  if (result < 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot write to file")));
+}
+
+/**
+  \rst
+  Formats a string and prints it to the specified file stream using ANSI
+  escape sequences to specify text formatting.
+
+  **Example**::
+
+    fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
+               "Elapsed time: {0:.2f} seconds", 1.23);
+  \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) {
+  vprint(f, ts, format_str,
+         fmt::make_format_args<buffer_context<char_t<S>>>(args...));
+}
+
+/**
+  \rst
+  Formats a string and prints it to stdout using ANSI escape sequences to
+  specify text formatting.
+
+  **Example**::
+
+    fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
+               "Elapsed time: {0:.2f} seconds", 1.23);
+  \endrst
+ */
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_string<S>::value)>
+void print(const text_style& ts, const S& format_str, const Args&... args) {
+  return print(stdout, ts, format_str, args...);
+}
+
+template <typename S, typename Char = char_t<S>>
+inline auto vformat(
+    const text_style& ts, const S& format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args)
+    -> std::basic_string<Char> {
+  basic_memory_buffer<Char> buf;
+  detail::vformat_to(buf, ts, detail::to_string_view(format_str), args);
+  return fmt::to_string(buf);
+}
+
+/**
+  \rst
+  Formats arguments and returns the result as a string using ANSI
+  escape sequences to specify text formatting.
+
+  **Example**::
+
+    #include <fmt/color.h>
+    std::string message = fmt::format(fmt::emphasis::bold | fg(fmt::color::red),
+                                      "The answer is {}", 42);
+  \endrst
+*/
+template <typename S, typename... Args, typename Char = char_t<S>>
+inline auto format(const text_style& ts, const S& format_str,
+                   const Args&... args) -> std::basic_string<Char> {
+  return fmt::vformat(ts, detail::to_string_view(format_str),
+                      fmt::make_format_args<buffer_context<Char>>(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)>
+auto vformat_to(OutputIt out, const text_style& ts,
+                basic_string_view<Char> format_str,
+                basic_format_args<buffer_context<type_identity_t<Char>>> args)
+    -> OutputIt {
+  auto&& buf = detail::get_buffer<Char>(out);
+  detail::vformat_to(buf, ts, format_str, args);
+  return detail::get_iterator(buf, out);
+}
+
+/**
+  \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, detail::to_string_view(format_str),
+                    fmt::make_format_args<buffer_context<char_t<S>>>(args...));
+}
+
+template <typename T, typename Char>
+struct formatter<detail::styled_arg<T>, Char> : formatter<T, Char> {
+  template <typename FormatContext>
+  auto format(const detail::styled_arg<T>& arg, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    const auto& ts = arg.style;
+    const auto& value = arg.value;
+    auto out = ctx.out();
+
+    bool has_style = false;
+    if (ts.has_emphasis()) {
+      has_style = true;
+      auto emphasis = detail::make_emphasis<Char>(ts.get_emphasis());
+      out = std::copy(emphasis.begin(), emphasis.end(), out);
+    }
+    if (ts.has_foreground()) {
+      has_style = true;
+      auto foreground =
+          detail::make_foreground_color<Char>(ts.get_foreground());
+      out = std::copy(foreground.begin(), foreground.end(), out);
+    }
+    if (ts.has_background()) {
+      has_style = true;
+      auto background =
+          detail::make_background_color<Char>(ts.get_background());
+      out = std::copy(background.begin(), background.end(), out);
+    }
+    out = formatter<T, Char>::format(value, ctx);
+    if (has_style) {
+      auto reset_color = string_view("\x1b[0m");
+      out = std::copy(reset_color.begin(), reset_color.end(), out);
+    }
+    return out;
+  }
+};
+
+/**
+  \rst
+  Returns an argument that will be formatted using ANSI escape sequences,
+  to be used in a formatting function.
+
+  **Example**::
+
+    fmt::print("Elapsed time: {0:.2f} seconds",
+               fmt::styled(1.23, fmt::fg(fmt::color::green) |
+                                 fmt::bg(fmt::color::blue)));
+  \endrst
+ */
+template <typename T>
+FMT_CONSTEXPR auto styled(const T& value, text_style ts)
+    -> detail::styled_arg<remove_cvref_t<T>> {
+  return detail::styled_arg<remove_cvref_t<T>>{value, ts};
+}
+
+FMT_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_COLOR_H_

include/fmt/compile.h

@@ -0,0 +1,535 @@
+// Formatting library for C++ - experimental format string compilation
+//
+// Copyright (c) 2012 - present, Victor Zverovich and fmt contributors
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_COMPILE_H_
+#define FMT_COMPILE_H_
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template <typename Char, typename InputIt>
+FMT_CONSTEXPR inline auto copy_str(InputIt begin, InputIt end,
+                                   counting_iterator it) -> counting_iterator {
+  return it + (end - begin);
+}
+
+// A compile-time string which is compiled into fast formatting code.
+class compiled_string {};
+
+template <typename S>
+struct is_compiled_string : std::is_base_of<compiled_string, S> {};
+
+/**
+  \rst
+  Converts a string literal *s* into a format string that will be parsed at
+  compile time and converted into efficient formatting code. Requires C++17
+  ``constexpr if`` compiler support.
+
+  **Example**::
+
+    // Converts 42 into std::string using the most efficient method and no
+    // runtime format string processing.
+    std::string s = fmt::format(FMT_COMPILE("{}"), 42);
+  \endrst
+ */
+#if defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+#  define FMT_COMPILE(s) \
+    FMT_STRING_IMPL(s, fmt::detail::compiled_string, explicit)
+#else
+#  define FMT_COMPILE(s) FMT_STRING(s)
+#endif
+
+#if FMT_USE_NONTYPE_TEMPLATE_ARGS
+template <typename Char, size_t N,
+          fmt::detail_exported::fixed_string<Char, N> Str>
+struct udl_compiled_string : compiled_string {
+  using char_type = Char;
+  explicit constexpr operator basic_string_view<char_type>() const {
+    return {Str.data, N - 1};
+  }
+};
+#endif
+
+template <typename T, typename... Tail>
+auto first(const T& value, const Tail&...) -> const T& {
+  return value;
+}
+
+#if defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+template <typename... Args> struct type_list {};
+
+// Returns a reference to the argument at index N from [first, rest...].
+template <int N, typename T, typename... Args>
+constexpr const auto& get([[maybe_unused]] const T& first,
+                          [[maybe_unused]] const Args&... rest) {
+  static_assert(N < 1 + sizeof...(Args), "index is out of bounds");
+  if constexpr (N == 0)
+    return first;
+  else
+    return detail::get<N - 1>(rest...);
+}
+
+template <typename Char, typename... Args>
+constexpr int get_arg_index_by_name(basic_string_view<Char> name,
+                                    type_list<Args...>) {
+  return get_arg_index_by_name<Args...>(name);
+}
+
+template <int N, typename> struct get_type_impl;
+
+template <int N, typename... Args> struct get_type_impl<N, type_list<Args...>> {
+  using type =
+      remove_cvref_t<decltype(detail::get<N>(std::declval<Args>()...))>;
+};
+
+template <int N, typename T>
+using get_type = typename get_type_impl<N, T>::type;
+
+template <typename T> struct is_compiled_format : std::false_type {};
+
+template <typename Char> struct text {
+  basic_string_view<Char> data;
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&...) const {
+    return write<Char>(out, data);
+  }
+};
+
+template <typename Char>
+struct is_compiled_format<text<Char>> : std::true_type {};
+
+template <typename Char>
+constexpr text<Char> make_text(basic_string_view<Char> s, size_t pos,
+                               size_t size) {
+  return {{&s[pos], size}};
+}
+
+template <typename Char> struct code_unit {
+  Char value;
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&...) const {
+    *out++ = value;
+    return out;
+  }
+};
+
+// This ensures that the argument type is convertible to `const T&`.
+template <typename T, int N, typename... Args>
+constexpr const T& get_arg_checked(const Args&... args) {
+  const auto& arg = detail::get<N>(args...);
+  if constexpr (detail::is_named_arg<remove_cvref_t<decltype(arg)>>()) {
+    return arg.value;
+  } else {
+    return arg;
+  }
+}
+
+template <typename Char>
+struct is_compiled_format<code_unit<Char>> : std::true_type {};
+
+// A replacement field that refers to argument N.
+template <typename Char, typename T, int N> struct field {
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&... args) const {
+    const T& arg = get_arg_checked<T, N>(args...);
+    if constexpr (std::is_convertible_v<T, basic_string_view<Char>>) {
+      auto s = basic_string_view<Char>(arg);
+      return copy_str<Char>(s.begin(), s.end(), out);
+    }
+    return write<Char>(out, arg);
+  }
+};
+
+template <typename Char, typename T, int N>
+struct is_compiled_format<field<Char, T, N>> : std::true_type {};
+
+// A replacement field that refers to argument with name.
+template <typename Char> struct runtime_named_field {
+  using char_type = Char;
+  basic_string_view<Char> name;
+
+  template <typename OutputIt, typename T>
+  constexpr static bool try_format_argument(
+      OutputIt& out,
+      // [[maybe_unused]] due to unused-but-set-parameter warning in GCC 7,8,9
+      [[maybe_unused]] basic_string_view<Char> arg_name, const T& arg) {
+    if constexpr (is_named_arg<typename std::remove_cv<T>::type>::value) {
+      if (arg_name == arg.name) {
+        out = write<Char>(out, arg.value);
+        return true;
+      }
+    }
+    return false;
+  }
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&... args) const {
+    bool found = (try_format_argument(out, name, args) || ...);
+    if (!found) {
+      FMT_THROW(format_error("argument with specified name is not found"));
+    }
+    return out;
+  }
+};
+
+template <typename Char>
+struct is_compiled_format<runtime_named_field<Char>> : std::true_type {};
+
+// A replacement field that refers to argument N and has format specifiers.
+template <typename Char, typename T, int N> struct spec_field {
+  using char_type = Char;
+  formatter<T, Char> fmt;
+
+  template <typename OutputIt, typename... Args>
+  constexpr FMT_INLINE OutputIt format(OutputIt out,
+                                       const Args&... args) const {
+    const auto& vargs =
+        fmt::make_format_args<basic_format_context<OutputIt, Char>>(args...);
+    basic_format_context<OutputIt, Char> ctx(out, vargs);
+    return fmt.format(get_arg_checked<T, N>(args...), ctx);
+  }
+};
+
+template <typename Char, typename T, int N>
+struct is_compiled_format<spec_field<Char, T, N>> : std::true_type {};
+
+template <typename L, typename R> struct concat {
+  L lhs;
+  R rhs;
+  using char_type = typename L::char_type;
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&... args) const {
+    out = lhs.format(out, args...);
+    return rhs.format(out, args...);
+  }
+};
+
+template <typename L, typename R>
+struct is_compiled_format<concat<L, R>> : std::true_type {};
+
+template <typename L, typename R>
+constexpr concat<L, R> make_concat(L lhs, R rhs) {
+  return {lhs, rhs};
+}
+
+struct unknown_format {};
+
+template <typename Char>
+constexpr size_t parse_text(basic_string_view<Char> str, size_t pos) {
+  for (size_t size = str.size(); pos != size; ++pos) {
+    if (str[pos] == '{' || str[pos] == '}') break;
+  }
+  return pos;
+}
+
+template <typename Args, size_t POS, int ID, typename S>
+constexpr auto compile_format_string(S format_str);
+
+template <typename Args, size_t POS, int ID, typename T, typename S>
+constexpr auto parse_tail(T head, S format_str) {
+  if constexpr (POS !=
+                basic_string_view<typename S::char_type>(format_str).size()) {
+    constexpr auto tail = compile_format_string<Args, POS, ID>(format_str);
+    if constexpr (std::is_same<remove_cvref_t<decltype(tail)>,
+                               unknown_format>())
+      return tail;
+    else
+      return make_concat(head, tail);
+  } else {
+    return head;
+  }
+}
+
+template <typename T, typename Char> struct parse_specs_result {
+  formatter<T, Char> fmt;
+  size_t end;
+  int next_arg_id;
+};
+
+enum { manual_indexing_id = -1 };
+
+template <typename T, typename Char>
+constexpr parse_specs_result<T, Char> parse_specs(basic_string_view<Char> str,
+                                                  size_t pos, int next_arg_id) {
+  str.remove_prefix(pos);
+  auto ctx =
+      compile_parse_context<Char>(str, max_value<int>(), nullptr, next_arg_id);
+  auto f = formatter<T, Char>();
+  auto end = f.parse(ctx);
+  return {f, pos + fmt::detail::to_unsigned(end - str.data()),
+          next_arg_id == 0 ? manual_indexing_id : ctx.next_arg_id()};
+}
+
+template <typename Char> struct arg_id_handler {
+  arg_ref<Char> arg_id;
+
+  constexpr int on_auto() {
+    FMT_ASSERT(false, "handler cannot be used with automatic indexing");
+    return 0;
+  }
+  constexpr int on_index(int id) {
+    arg_id = arg_ref<Char>(id);
+    return 0;
+  }
+  constexpr int on_name(basic_string_view<Char> id) {
+    arg_id = arg_ref<Char>(id);
+    return 0;
+  }
+};
+
+template <typename Char> struct parse_arg_id_result {
+  arg_ref<Char> arg_id;
+  const Char* arg_id_end;
+};
+
+template <int ID, typename Char>
+constexpr auto parse_arg_id(const Char* begin, const Char* end) {
+  auto handler = arg_id_handler<Char>{arg_ref<Char>{}};
+  auto arg_id_end = parse_arg_id(begin, end, handler);
+  return parse_arg_id_result<Char>{handler.arg_id, arg_id_end};
+}
+
+template <typename T, typename Enable = void> struct field_type {
+  using type = remove_cvref_t<T>;
+};
+
+template <typename T>
+struct field_type<T, enable_if_t<detail::is_named_arg<T>::value>> {
+  using type = remove_cvref_t<decltype(T::value)>;
+};
+
+template <typename T, typename Args, size_t END_POS, int ARG_INDEX, int NEXT_ID,
+          typename S>
+constexpr auto parse_replacement_field_then_tail(S format_str) {
+  using char_type = typename S::char_type;
+  constexpr auto str = basic_string_view<char_type>(format_str);
+  constexpr char_type c = END_POS != str.size() ? str[END_POS] : char_type();
+  if constexpr (c == '}') {
+    return parse_tail<Args, END_POS + 1, NEXT_ID>(
+        field<char_type, typename field_type<T>::type, ARG_INDEX>(),
+        format_str);
+  } else if constexpr (c != ':') {
+    FMT_THROW(format_error("expected ':'"));
+  } else {
+    constexpr auto result = parse_specs<typename field_type<T>::type>(
+        str, END_POS + 1, NEXT_ID == manual_indexing_id ? 0 : NEXT_ID);
+    if constexpr (result.end >= str.size() || str[result.end] != '}') {
+      FMT_THROW(format_error("expected '}'"));
+      return 0;
+    } else {
+      return parse_tail<Args, result.end + 1, result.next_arg_id>(
+          spec_field<char_type, typename field_type<T>::type, ARG_INDEX>{
+              result.fmt},
+          format_str);
+    }
+  }
+}
+
+// Compiles a non-empty format string and returns the compiled representation
+// or unknown_format() on unrecognized input.
+template <typename Args, size_t POS, int ID, typename S>
+constexpr auto compile_format_string(S format_str) {
+  using char_type = typename S::char_type;
+  constexpr auto str = basic_string_view<char_type>(format_str);
+  if constexpr (str[POS] == '{') {
+    if constexpr (POS + 1 == str.size())
+      FMT_THROW(format_error("unmatched '{' in format string"));
+    if constexpr (str[POS + 1] == '{') {
+      return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), format_str);
+    } else if constexpr (str[POS + 1] == '}' || str[POS + 1] == ':') {
+      static_assert(ID != manual_indexing_id,
+                    "cannot switch from manual to automatic argument indexing");
+      constexpr auto next_id =
+          ID != manual_indexing_id ? ID + 1 : manual_indexing_id;
+      return parse_replacement_field_then_tail<get_type<ID, Args>, Args,
+                                               POS + 1, ID, next_id>(
+          format_str);
+    } else {
+      constexpr auto arg_id_result =
+          parse_arg_id<ID>(str.data() + POS + 1, str.data() + str.size());
+      constexpr auto arg_id_end_pos = arg_id_result.arg_id_end - str.data();
+      constexpr char_type c =
+          arg_id_end_pos != str.size() ? str[arg_id_end_pos] : char_type();
+      static_assert(c == '}' || c == ':', "missing '}' in format string");
+      if constexpr (arg_id_result.arg_id.kind == arg_id_kind::index) {
+        static_assert(
+            ID == manual_indexing_id || ID == 0,
+            "cannot switch from automatic to manual argument indexing");
+        constexpr auto arg_index = arg_id_result.arg_id.val.index;
+        return parse_replacement_field_then_tail<get_type<arg_index, Args>,
+                                                 Args, arg_id_end_pos,
+                                                 arg_index, manual_indexing_id>(
+            format_str);
+      } else if constexpr (arg_id_result.arg_id.kind == arg_id_kind::name) {
+        constexpr auto arg_index =
+            get_arg_index_by_name(arg_id_result.arg_id.val.name, Args{});
+        if constexpr (arg_index >= 0) {
+          constexpr auto next_id =
+              ID != manual_indexing_id ? ID + 1 : manual_indexing_id;
+          return parse_replacement_field_then_tail<
+              decltype(get_type<arg_index, Args>::value), Args, arg_id_end_pos,
+              arg_index, next_id>(format_str);
+        } else if constexpr (c == '}') {
+          return parse_tail<Args, arg_id_end_pos + 1, ID>(
+              runtime_named_field<char_type>{arg_id_result.arg_id.val.name},
+              format_str);
+        } else if constexpr (c == ':') {
+          return unknown_format();  // no type info for specs parsing
+        }
+      }
+    }
+  } else if constexpr (str[POS] == '}') {
+    if constexpr (POS + 1 == str.size())
+      FMT_THROW(format_error("unmatched '}' in format string"));
+    return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), format_str);
+  } else {
+    constexpr auto end = parse_text(str, POS + 1);
+    if constexpr (end - POS > 1) {
+      return parse_tail<Args, end, ID>(make_text(str, POS, end - POS),
+                                       format_str);
+    } else {
+      return parse_tail<Args, end, ID>(code_unit<char_type>{str[POS]},
+                                       format_str);
+    }
+  }
+}
+
+template <typename... Args, typename S,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+constexpr auto compile(S format_str) {
+  constexpr auto str = basic_string_view<typename S::char_type>(format_str);
+  if constexpr (str.size() == 0) {
+    return detail::make_text(str, 0, 0);
+  } else {
+    constexpr auto result =
+        detail::compile_format_string<detail::type_list<Args...>, 0, 0>(
+            format_str);
+    return result;
+  }
+}
+#endif  // defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+}  // namespace detail
+
+FMT_BEGIN_EXPORT
+
+#if defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+
+template <typename CompiledFormat, typename... Args,
+          typename Char = typename CompiledFormat::char_type,
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+FMT_INLINE std::basic_string<Char> format(const CompiledFormat& cf,
+                                          const Args&... args) {
+  auto s = std::basic_string<Char>();
+  cf.format(std::back_inserter(s), args...);
+  return s;
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+constexpr FMT_INLINE OutputIt format_to(OutputIt out, const CompiledFormat& cf,
+                                        const Args&... args) {
+  return cf.format(out, args...);
+}
+
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+FMT_INLINE std::basic_string<typename S::char_type> format(const S&,
+                                                           Args&&... args) {
+  if constexpr (std::is_same<typename S::char_type, char>::value) {
+    constexpr auto str = basic_string_view<typename S::char_type>(S());
+    if constexpr (str.size() == 2 && str[0] == '{' && str[1] == '}') {
+      const auto& first = detail::first(args...);
+      if constexpr (detail::is_named_arg<
+                        remove_cvref_t<decltype(first)>>::value) {
+        return fmt::to_string(first.value);
+      } else {
+        return fmt::to_string(first);
+      }
+    }
+  }
+  constexpr auto compiled = detail::compile<Args...>(S());
+  if constexpr (std::is_same<remove_cvref_t<decltype(compiled)>,
+                             detail::unknown_format>()) {
+    return fmt::format(
+        static_cast<basic_string_view<typename S::char_type>>(S()),
+        std::forward<Args>(args)...);
+  } else {
+    return fmt::format(compiled, std::forward<Args>(args)...);
+  }
+}
+
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+FMT_CONSTEXPR OutputIt format_to(OutputIt out, const S&, Args&&... args) {
+  constexpr auto compiled = detail::compile<Args...>(S());
+  if constexpr (std::is_same<remove_cvref_t<decltype(compiled)>,
+                             detail::unknown_format>()) {
+    return fmt::format_to(
+        out, static_cast<basic_string_view<typename S::char_type>>(S()),
+        std::forward<Args>(args)...);
+  } else {
+    return fmt::format_to(out, compiled, std::forward<Args>(args)...);
+  }
+}
+#endif
+
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+auto format_to_n(OutputIt out, size_t n, const S& format_str, Args&&... args)
+    -> format_to_n_result<OutputIt> {
+  using traits = detail::fixed_buffer_traits;
+  auto buf = detail::iterator_buffer<OutputIt, char, traits>(out, n);
+  fmt::format_to(std::back_inserter(buf), format_str,
+                 std::forward<Args>(args)...);
+  return {buf.out(), buf.count()};
+}
+
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+FMT_CONSTEXPR20 auto formatted_size(const S& format_str, const Args&... args)
+    -> size_t {
+  return fmt::format_to(detail::counting_iterator(), format_str, args...)
+      .count();
+}
+
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+void print(std::FILE* f, const S& format_str, const Args&... args) {
+  memory_buffer buffer;
+  fmt::format_to(std::back_inserter(buffer), format_str, args...);
+  detail::print(f, {buffer.data(), buffer.size()});
+}
+
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+void print(const S& format_str, const Args&... args) {
+  print(stdout, format_str, args...);
+}
+
+#if FMT_USE_NONTYPE_TEMPLATE_ARGS
+inline namespace literals {
+template <detail_exported::fixed_string Str> constexpr auto operator""_cf() {
+  using char_t = remove_cvref_t<decltype(Str.data[0])>;
+  return detail::udl_compiled_string<char_t, sizeof(Str.data) / sizeof(char_t),
+                                     Str>();
+}
+}  // namespace literals
+#endif
+
+FMT_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_COMPILE_H_

include/fmt/os.h

@@ -0,0 +1,455 @@
+// Formatting library for C++ - optional OS-specific functionality
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_OS_H_
+#define FMT_OS_H_
+
+#include <cerrno>
+#include <cstddef>
+#include <cstdio>
+#include <system_error>  // std::system_error
+
+#include "format.h"
+
+#if defined __APPLE__ || defined(__FreeBSD__)
+#  if FMT_HAS_INCLUDE(<xlocale.h>)
+#    include <xlocale.h>  // for LC_NUMERIC_MASK on OS X
+#  endif
+#endif
+
+#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(__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
+#  if defined(_WIN32) && !defined(__MINGW32__)
+// Fix warnings about deprecated symbols.
+#    define FMT_POSIX(call) _##call
+#  else
+#    define FMT_POSIX(call) call
+#  endif
+#endif
+
+// Calls to system functions are wrapped in FMT_SYSTEM for testability.
+#ifdef FMT_SYSTEM
+#  define FMT_HAS_SYSTEM
+#  define FMT_POSIX_CALL(call) FMT_SYSTEM(call)
+#else
+#  define FMT_SYSTEM(call) ::call
+#  ifdef _WIN32
+// Fix warnings about deprecated symbols.
+#    define FMT_POSIX_CALL(call) ::_##call
+#  else
+#    define FMT_POSIX_CALL(call) ::call
+#  endif
+#endif
+
+// Retries the expression while it evaluates to error_result and errno
+// equals to EINTR.
+#ifndef _WIN32
+#  define FMT_RETRY_VAL(result, expression, error_result) \
+    do {                                                  \
+      (result) = (expression);                            \
+    } while ((result) == (error_result) && errno == EINTR)
+#else
+#  define FMT_RETRY_VAL(result, expression, error_result) result = (expression)
+#endif
+
+#define FMT_RETRY(result, expression) FMT_RETRY_VAL(result, expression, -1)
+
+FMT_BEGIN_NAMESPACE
+FMT_BEGIN_EXPORT
+
+/**
+  \rst
+  A reference to a null-terminated string. It can be constructed from a C
+  string or ``std::string``.
+
+  You can use one of the following type aliases for common character types:
+
+  +---------------+-----------------------------+
+  | Type          | Definition                  |
+  +===============+=============================+
+  | cstring_view  | basic_cstring_view<char>    |
+  +---------------+-----------------------------+
+  | wcstring_view | basic_cstring_view<wchar_t> |
+  +---------------+-----------------------------+
+
+  This class is most useful as a parameter type to allow passing
+  different types of strings to a function, for example::
+
+    template <typename... Args>
+    std::string format(cstring_view format_str, const Args & ... args);
+
+    format("{}", 42);
+    format(std::string("{}"), 42);
+  \endrst
+ */
+template <typename Char> class basic_cstring_view {
+ private:
+  const Char* data_;
+
+ public:
+  /** Constructs a string reference object from a C string. */
+  basic_cstring_view(const Char* s) : data_(s) {}
+
+  /**
+    \rst
+    Constructs a string reference from an ``std::string`` object.
+    \endrst
+   */
+  basic_cstring_view(const std::basic_string<Char>& s) : data_(s.c_str()) {}
+
+  /** Returns the pointer to a C string. */
+  auto c_str() const -> const Char* { return data_; }
+};
+
+using cstring_view = basic_cstring_view<char>;
+using wcstring_view = basic_cstring_view<wchar_t>;
+
+#ifdef _WIN32
+FMT_API const std::error_category& system_category() noexcept;
+
+namespace detail {
+FMT_API void format_windows_error(buffer<char>& out, int error_code,
+                                  const char* message) noexcept;
+}
+
+FMT_API std::system_error vwindows_error(int error_code, string_view format_str,
+                                         format_args args);
+
+/**
+ \rst
+ Constructs a :class:`std::system_error` object with the description
+ of the form
+
+ .. parsed-literal::
+   *<message>*: *<system-message>*
+
+ where *<message>* is the formatted message and *<system-message>* is the
+ system message corresponding to the error code.
+ *error_code* is a Windows error code as given by ``GetLastError``.
+ If *error_code* is not a valid error code such as -1, the system message
+ will look like "error -1".
+
+ **Example**::
+
+   // This throws a 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, const char* message) noexcept;
+#else
+inline auto system_category() noexcept -> const std::error_category& {
+  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:
+  FILE* file_;
+
+  friend class file;
+
+  explicit buffered_file(FILE* f) : file_(f) {}
+
+ public:
+  buffered_file(const buffered_file&) = delete;
+  void operator=(const buffered_file&) = delete;
+
+  // Constructs a buffered_file object which doesn't represent any file.
+  buffered_file() noexcept : file_(nullptr) {}
+
+  // Destroys the object closing the file it represents if any.
+  FMT_API ~buffered_file() noexcept;
+
+ public:
+  buffered_file(buffered_file&& other) noexcept : file_(other.file_) {
+    other.file_ = nullptr;
+  }
+
+  auto operator=(buffered_file&& other) -> buffered_file& {
+    close();
+    file_ = other.file_;
+    other.file_ = nullptr;
+    return *this;
+  }
+
+  // Opens a file.
+  FMT_API buffered_file(cstring_view filename, cstring_view mode);
+
+  // Closes the file.
+  FMT_API void close();
+
+  // Returns the pointer to a FILE object representing this file.
+  auto get() const noexcept -> FILE* { return file_; }
+
+  FMT_API auto descriptor() const -> int;
+
+  void vprint(string_view format_str, format_args args) {
+    fmt::vprint(file_, format_str, args);
+  }
+
+  template <typename... Args>
+  inline void print(string_view format_str, const Args&... args) {
+    vprint(format_str, fmt::make_format_args(args...));
+  }
+};
+
+#if FMT_USE_FCNTL
+// A file. Closed file is represented by a file object with descriptor -1.
+// Methods that are not declared with noexcept may throw
+// fmt::system_error in case of failure. Note that some errors such as
+// closing the file multiple times will cause a crash on Windows rather
+// than an exception. You can get standard behavior by overriding the
+// invalid parameter handler with _set_invalid_parameter_handler.
+class FMT_API file {
+ private:
+  int fd_;  // File descriptor.
+
+  // Constructs a file object with a given descriptor.
+  explicit file(int fd) : fd_(fd) {}
+
+ public:
+  // Possible values for the oflag argument to the constructor.
+  enum {
+    RDONLY = FMT_POSIX(O_RDONLY),  // Open for reading only.
+    WRONLY = FMT_POSIX(O_WRONLY),  // Open for writing only.
+    RDWR = FMT_POSIX(O_RDWR),      // Open for reading and writing.
+    CREATE = FMT_POSIX(O_CREAT),   // Create if the file doesn't exist.
+    APPEND = FMT_POSIX(O_APPEND),  // Open in append mode.
+    TRUNC = FMT_POSIX(O_TRUNC)     // Truncate the content of the file.
+  };
+
+  // Constructs a file object which doesn't represent any file.
+  file() noexcept : fd_(-1) {}
+
+  // Opens a file and constructs a file object representing this file.
+  file(cstring_view path, int oflag);
+
+ public:
+  file(const file&) = delete;
+  void operator=(const file&) = delete;
+
+  file(file&& other) noexcept : fd_(other.fd_) { other.fd_ = -1; }
+
+  // Move assignment is not noexcept because close may throw.
+  auto operator=(file&& other) -> file& {
+    close();
+    fd_ = other.fd_;
+    other.fd_ = -1;
+    return *this;
+  }
+
+  // Destroys the object closing the file it represents if any.
+  ~file() noexcept;
+
+  // Returns the file descriptor.
+  auto descriptor() const noexcept -> int { return fd_; }
+
+  // Closes the file.
+  void close();
+
+  // Returns the file size. The size has signed type for consistency with
+  // stat::st_size.
+  auto size() const -> long long;
+
+  // Attempts to read count bytes from the file into the specified buffer.
+  auto read(void* buffer, size_t count) -> size_t;
+
+  // Attempts to write count bytes from the specified buffer to the file.
+  auto write(const void* buffer, size_t count) -> size_t;
+
+  // Duplicates a file descriptor with the dup function and returns
+  // the duplicate as a file object.
+  static auto dup(int fd) -> file;
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  void dup2(int fd);
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  void dup2(int fd, std::error_code& ec) noexcept;
+
+  // Creates a pipe setting up read_end and write_end file objects for reading
+  // and writing respectively.
+  // DEPRECATED! Taking files as out parameters is deprecated.
+  static void pipe(file& read_end, file& write_end);
+
+  // Creates a buffered_file object associated with this file and detaches
+  // this file object from the file.
+  auto fdopen(const char* mode) -> buffered_file;
+
+#  if defined(_WIN32) && !defined(__MINGW32__)
+  // Opens a file and constructs a file object representing this file by
+  // wcstring_view filename. Windows only.
+  static file open_windows_file(wcstring_view path, int oflag);
+#  endif
+};
+
+// Returns the memory page size.
+auto getpagesize() -> long;
+
+namespace detail {
+
+struct buffer_size {
+  buffer_size() = default;
+  size_t value = 0;
+  auto operator=(size_t val) const -> buffer_size {
+    auto bs = buffer_size();
+    bs.value = val;
+    return bs;
+  }
+};
+
+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
+};
+
+class file_buffer final : public buffer<char> {
+  file file_;
+
+  FMT_API void grow(size_t) override;
+
+ public:
+  FMT_API file_buffer(cstring_view path, const ostream_params& params);
+  FMT_API file_buffer(file_buffer&& other);
+  FMT_API ~file_buffer();
+
+  void flush() {
+    if (size() == 0) return;
+    file_.write(data(), size() * sizeof(data()[0]));
+    clear();
+  }
+
+  void close() {
+    flush();
+    file_.close();
+  }
+};
+
+}  // namespace detail
+
+// 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 {
+ private:
+  FMT_MSC_WARNING(suppress : 4251)
+  detail::file_buffer buffer_;
+
+  ostream(cstring_view path, const detail::ostream_params& params)
+      : buffer_(path, params) {}
+
+ public:
+  ostream(ostream&& other) : buffer_(std::move(other.buffer_)) {}
+
+  ~ostream();
+
+  void flush() { buffer_.flush(); }
+
+  template <typename... T>
+  friend auto output_file(cstring_view path, T... params) -> ostream;
+
+  void close() { buffer_.close(); }
+
+  /**
+    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(std::back_inserter(buffer_), 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 | file::TRUNC`` 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 auto output_file(cstring_view path, T... params) -> ostream {
+  return {path, detail::ostream_params(params...)};
+}
+#endif  // FMT_USE_FCNTL
+
+FMT_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_OS_H_

include/fmt/ostream.h

@@ -1,6 +1,6 @@
 // Formatting library for C++ - std::ostream support
 //
-// Copyright (c) 2012 - 2016, Victor Zverovich
+// Copyright (c) 2012 - present, Victor Zverovich
 // All rights reserved.
 //
 // For the license information refer to format.h.
@@ -8,134 +8,199 @@
 #ifndef FMT_OSTREAM_H_
 #define FMT_OSTREAM_H_
 
+#include <fstream>  // std::filebuf
+
+#ifdef _WIN32
+#  ifdef __GLIBCXX__
+#    include <ext/stdio_filebuf.h>
+#    include <ext/stdio_sync_filebuf.h>
+#  endif
+#  include <io.h>
+#endif
+
 #include "format.h"
-#include <ostream>
 
 FMT_BEGIN_NAMESPACE
-namespace internal {
+namespace detail {
 
-template <class Char>
-class formatbuf : public std::basic_streambuf<Char> {
+template <typename Streambuf> class formatbuf : public Streambuf {
  private:
-  typedef typename std::basic_streambuf<Char>::int_type int_type;
-  typedef typename std::basic_streambuf<Char>::traits_type traits_type;
+  using char_type = typename Streambuf::char_type;
+  using streamsize = decltype(std::declval<Streambuf>().sputn(nullptr, 0));
+  using int_type = typename Streambuf::int_type;
+  using traits_type = typename Streambuf::traits_type;
 
-  basic_buffer<Char> &buffer_;
+  buffer<char_type>& buffer_;
 
  public:
-  formatbuf(basic_buffer<Char> &buffer) : buffer_(buffer) {}
+  explicit formatbuf(buffer<char_type>& 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.
+  // The put area is 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. A 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 {
+  auto overflow(int_type ch) -> int_type override {
     if (!traits_type::eq_int_type(ch, traits_type::eof()))
-      buffer_.push_back(static_cast<Char>(ch));
+      buffer_.push_back(static_cast<char_type>(ch));
     return ch;
   }
 
-  std::streamsize xsputn(const Char *s, std::streamsize count) FMT_OVERRIDE {
+  auto xsputn(const char_type* s, streamsize count) -> streamsize override {
     buffer_.append(s, s + count);
     return count;
   }
 };
 
-template <typename Char>
-struct test_stream : std::basic_ostream<Char> {
- private:
-  struct null;
-  // Hide all operator<< from std::basic_ostream<Char>.
-  void operator<<(null);
+// Generate a unique explicit instantion in every translation unit using a tag
+// type in an anonymous namespace.
+namespace {
+struct file_access_tag {};
+}  // namespace
+template <typename Tag, typename BufType, FILE* BufType::*FileMemberPtr>
+class file_access {
+  friend auto get_file(BufType& obj) -> FILE* { return obj.*FileMemberPtr; }
 };
 
-// Checks if T has an overloaded operator<< which is a free function (not a
-// member of std::ostream).
-template <typename T, typename Char>
-class is_streamable {
- private:
-  template <typename U>
-  static decltype(
-    internal::declval<test_stream<Char>&>()
-      << internal::declval<U>(), std::true_type()) test(int);
+#if FMT_MSC_VERSION
+template class file_access<file_access_tag, std::filebuf,
+                           &std::filebuf::_Myfile>;
+auto get_file(std::filebuf&) -> FILE*;
+#endif
 
-  template <typename>
-  static std::false_type test(...);
-
-  typedef decltype(test<T>(0)) result;
-
- public:
-  static const bool value = result::value;
-};
-
-// Disable conversion to int if T has an overloaded operator<< which is a free
-// function (not a member of std::ostream).
-template <typename T, typename Char>
-class convert_to_int<T, Char, true> {
- public:
-  static const bool value =
-    convert_to_int<T, Char, false>::value && !is_streamable<T, Char>::value;
-};
+inline auto write_ostream_unicode(std::ostream& os, fmt::string_view data)
+    -> bool {
+  FILE* f = nullptr;
+#if FMT_MSC_VERSION
+  if (auto* buf = dynamic_cast<std::filebuf*>(os.rdbuf()))
+    f = get_file(*buf);
+  else
+    return false;
+#elif defined(_WIN32) && defined(__GLIBCXX__)
+  auto* rdbuf = os.rdbuf();
+  if (auto* sfbuf = dynamic_cast<__gnu_cxx::stdio_sync_filebuf<char>*>(rdbuf))
+    f = sfbuf->file();
+  else if (auto* fbuf = dynamic_cast<__gnu_cxx::stdio_filebuf<char>*>(rdbuf))
+    f = fbuf->file();
+  else
+    return false;
+#else
+  ignore_unused(os, data, f);
+#endif
+#ifdef _WIN32
+  if (f) {
+    int fd = _fileno(f);
+    if (_isatty(fd)) {
+      os.flush();
+      return write_console(fd, data);
+    }
+  }
+#endif
+  return false;
+}
+inline auto write_ostream_unicode(std::wostream&,
+                                  fmt::basic_string_view<wchar_t>) -> bool {
+  return false;
+}
 
 // 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(std::basic_ostream<Char> &os, basic_buffer<Char> &buf) {
-  const Char *data = buf.data();
-  typedef std::make_unsigned<std::streamsize>::type UnsignedStreamSize;
-  UnsignedStreamSize size = buf.size();
-  UnsignedStreamSize max_size =
-      internal::to_unsigned((std::numeric_limits<std::streamsize>::max)());
+void write_buffer(std::basic_ostream<Char>& os, buffer<Char>& buf) {
+  const Char* buf_data = buf.data();
+  using unsigned_streamsize = std::make_unsigned<std::streamsize>::type;
+  unsigned_streamsize size = buf.size();
+  unsigned_streamsize max_size = to_unsigned(max_value<std::streamsize>());
   do {
-    UnsignedStreamSize n = size <= max_size ? size : max_size;
-    os.write(data, static_cast<std::streamsize>(n));
-    data += n;
+    unsigned_streamsize n = size <= max_size ? size : max_size;
+    os.write(buf_data, static_cast<std::streamsize>(n));
+    buf_data += n;
     size -= n;
   } while (size != 0);
 }
 
 template <typename Char, typename T>
-void format_value(basic_buffer<Char> &buffer, const T &value) {
-  internal::formatbuf<Char> format_buf(buffer);
-  std::basic_ostream<Char> output(&format_buf);
-  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
+void format_value(buffer<Char>& buf, const T& value) {
+  auto&& format_buf = formatbuf<std::basic_streambuf<Char>>(buf);
+  auto&& output = std::basic_ostream<Char>(&format_buf);
+#if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
+  output.imbue(std::locale::classic());  // The default is always unlocalized.
+#endif
   output << value;
-  buffer.resize(buffer.size());
+  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
 }
 
-// Disable builtin formatting of enums and use operator<< instead.
-template <typename T>
-struct format_enum<T,
-    typename std::enable_if<std::is_enum<T>::value>::type> : std::false_type {};
-}  // namespace internal
+template <typename T> struct streamed_view {
+  const T& value;
+};
+
+}  // namespace detail
 
 // Formats an object of type T that has an overloaded ostream operator<<.
-template <typename T, typename Char>
-struct formatter<T, Char,
-    typename std::enable_if<internal::is_streamable<T, Char>::value>::type>
-    : formatter<basic_string_view<Char>, Char> {
+template <typename Char>
+struct basic_ostream_formatter : formatter<basic_string_view<Char>, Char> {
+  void set_debug_format() = delete;
 
-  template <typename Context>
-  auto format(const T &value, Context &ctx) -> decltype(ctx.out()) {
-    basic_memory_buffer<Char> buffer;
-    internal::format_value(buffer, value);
-    basic_string_view<Char> str(buffer.data(), buffer.size());
-    formatter<basic_string_view<Char>, Char>::format(str, ctx);
-    return ctx.out();
+  template <typename T, typename OutputIt>
+  auto format(const T& value, basic_format_context<OutputIt, Char>& ctx) const
+      -> OutputIt {
+    auto buffer = basic_memory_buffer<Char>();
+    detail::format_value(buffer, value);
+    return formatter<basic_string_view<Char>, Char>::format(
+        {buffer.data(), buffer.size()}, ctx);
   }
 };
 
-template <typename Char>
-inline void vprint(std::basic_ostream<Char> &os,
-                   basic_string_view<Char> format_str,
-                   basic_format_args<typename buffer_context<Char>::type> args) {
-  basic_memory_buffer<Char> buffer;
-  vformat_to(buffer, format_str, args);
-  internal::write(os, buffer);
+using ostream_formatter = basic_ostream_formatter<char>;
+
+template <typename T, typename Char>
+struct formatter<detail::streamed_view<T>, Char>
+    : basic_ostream_formatter<Char> {
+  template <typename OutputIt>
+  auto format(detail::streamed_view<T> view,
+              basic_format_context<OutputIt, Char>& ctx) const -> OutputIt {
+    return basic_ostream_formatter<Char>::format(view.value, ctx);
+  }
+};
+
+/**
+  \rst
+  Returns a view that formats `value` via an ostream ``operator<<``.
+
+  **Example**::
+
+    fmt::print("Current thread id: {}\n",
+               fmt::streamed(std::this_thread::get_id()));
+  \endrst
+ */
+template <typename T>
+constexpr auto streamed(const T& value) -> detail::streamed_view<T> {
+  return {value};
 }
+
+namespace detail {
+
+inline void vprint_directly(std::ostream& os, string_view format_str,
+                            format_args args) {
+  auto buffer = memory_buffer();
+  detail::vformat_to(buffer, format_str, args);
+  detail::write_buffer(os, buffer);
+}
+
+}  // namespace detail
+
+FMT_EXPORT template <typename Char>
+void vprint(std::basic_ostream<Char>& os,
+            basic_string_view<type_identity_t<Char>> format_str,
+            basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  auto buffer = basic_memory_buffer<Char>();
+  detail::vformat_to(buffer, format_str, args);
+  if (detail::write_ostream_unicode(os, {buffer.data(), buffer.size()})) return;
+  detail::write_buffer(os, buffer);
+}
+
 /**
   \rst
   Prints formatted data to the stream *os*.
@@ -145,17 +210,36 @@ inline void vprint(std::basic_ostream<Char> &os,
     fmt::print(cerr, "Don't {}!", "panic");
   \endrst
  */
-template <typename... Args>
-inline void print(std::ostream &os, string_view format_str,
-                  const Args & ... args) {
-  vprint<char>(os, format_str, make_format_args<format_context>(args...));
+FMT_EXPORT template <typename... T>
+void print(std::ostream& os, format_string<T...> fmt, T&&... args) {
+  const auto& vargs = fmt::make_format_args(args...);
+  if (detail::is_utf8())
+    vprint(os, fmt, vargs);
+  else
+    detail::vprint_directly(os, fmt, vargs);
 }
 
+FMT_EXPORT
 template <typename... Args>
-inline void print(std::wostream &os, wstring_view format_str,
-                  const Args & ... args) {
-  vprint<wchar_t>(os, format_str, make_format_args<wformat_context>(args...));
+void print(std::wostream& os,
+           basic_format_string<wchar_t, type_identity_t<Args>...> fmt,
+           Args&&... args) {
+  vprint(os, fmt, fmt::make_format_args<buffer_context<wchar_t>>(args...));
 }
+
+FMT_EXPORT template <typename... T>
+void println(std::ostream& os, format_string<T...> fmt, T&&... args) {
+  fmt::print(os, "{}\n", fmt::format(fmt, std::forward<T>(args)...));
+}
+
+FMT_EXPORT
+template <typename... Args>
+void println(std::wostream& os,
+             basic_format_string<wchar_t, type_identity_t<Args>...> fmt,
+             Args&&... args) {
+  print(os, L"{}\n", fmt::format(fmt, std::forward<Args>(args)...));
+}
+
 FMT_END_NAMESPACE
 
 #endif  // FMT_OSTREAM_H_

include/fmt/posix.h

@@ -1,417 +0,0 @@
-// A C++ interface to POSIX functions.
-//
-// Copyright (c) 2012 - 2016, Victor Zverovich
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-#ifndef FMT_POSIX_H_
-#define FMT_POSIX_H_
-
-#if defined(__MINGW32__) || defined(__CYGWIN__)
-// Workaround MinGW bug https://sourceforge.net/p/mingw/bugs/2024/.
-# undef __STRICT_ANSI__
-#endif
-
-#include <errno.h>
-#include <fcntl.h>   // for O_RDONLY
-#include <locale.h>  // for locale_t
-#include <stdio.h>
-#include <stdlib.h>  // for strtod_l
-
-#include <cstddef>
-
-#if defined __APPLE__ || defined(__FreeBSD__)
-# include <xlocale.h>  // for LC_NUMERIC_MASK on OS X
-#endif
-
-#include "format.h"
-
-#ifndef FMT_POSIX
-# if defined(_WIN32) && !defined(__MINGW32__)
-// Fix warnings about deprecated symbols.
-#  define FMT_POSIX(call) _##call
-# else
-#  define FMT_POSIX(call) call
-# endif
-#endif
-
-// Calls to system functions are wrapped in FMT_SYSTEM for testability.
-#ifdef FMT_SYSTEM
-# define FMT_POSIX_CALL(call) FMT_SYSTEM(call)
-#else
-# define FMT_SYSTEM(call) call
-# ifdef _WIN32
-// Fix warnings about deprecated symbols.
-#  define FMT_POSIX_CALL(call) ::_##call
-# else
-#  define FMT_POSIX_CALL(call) ::call
-# endif
-#endif
-
-// Retries the expression while it evaluates to error_result and errno
-// equals to EINTR.
-#ifndef _WIN32
-# define FMT_RETRY_VAL(result, expression, error_result) \
-  do { \
-    result = (expression); \
-  } while (result == error_result && errno == EINTR)
-#else
-# define FMT_RETRY_VAL(result, expression, error_result) result = (expression)
-#endif
-
-#define FMT_RETRY(result, expression) FMT_RETRY_VAL(result, expression, -1)
-
-FMT_BEGIN_NAMESPACE
-
-/**
-  \rst
-  A reference to a null-terminated string. It can be constructed from a C
-  string or ``std::string``.
-
-  You can use one of the following typedefs for common character types:
-
-  +---------------+-----------------------------+
-  | Type          | Definition                  |
-  +===============+=============================+
-  | cstring_view  | basic_cstring_view<char>    |
-  +---------------+-----------------------------+
-  | wcstring_view | basic_cstring_view<wchar_t> |
-  +---------------+-----------------------------+
-
-  This class is most useful as a parameter type to allow passing
-  different types of strings to a function, for example::
-
-    template <typename... Args>
-    std::string format(cstring_view format_str, const Args & ... args);
-
-    format("{}", 42);
-    format(std::string("{}"), 42);
-  \endrst
- */
-template <typename Char>
-class basic_cstring_view {
- private:
-  const Char *data_;
-
- public:
-  /** Constructs a string reference object from a C string. */
-  basic_cstring_view(const Char *s) : data_(s) {}
-
-  /**
-    \rst
-    Constructs a string reference from an ``std::string`` object.
-    \endrst
-   */
-  basic_cstring_view(const std::basic_string<Char> &s) : data_(s.c_str()) {}
-
-  /** Returns the pointer to a C string. */
-  const Char *c_str() const { return data_; }
-};
-
-typedef basic_cstring_view<char> cstring_view;
-typedef basic_cstring_view<wchar_t> wcstring_view;
-
-// An error code.
-class error_code {
- private:
-  int value_;
-
- public:
-  explicit error_code(int value = 0) FMT_NOEXCEPT : value_(value) {}
-
-  int get() const FMT_NOEXCEPT { return value_; }
-};
-
-// A buffered file.
-class buffered_file {
- private:
-  FILE *file_;
-
-  friend class file;
-
-  explicit buffered_file(FILE *f) : file_(f) {}
-
- public:
-  // Constructs a buffered_file object which doesn't represent any file.
-  buffered_file() FMT_NOEXCEPT : file_(FMT_NULL) {}
-
-  // Destroys the object closing the file it represents if any.
-  FMT_API ~buffered_file() FMT_DTOR_NOEXCEPT;
-
-#if !FMT_USE_RVALUE_REFERENCES
-  // Emulate a move constructor and a move assignment operator if rvalue
-  // references are not supported.
-
- private:
-  // A proxy object to emulate a move constructor.
-  // It is private to make it impossible call operator Proxy directly.
-  struct Proxy {
-    FILE *file;
-  };
-
-public:
-  // A "move constructor" for moving from a temporary.
-  buffered_file(Proxy p) FMT_NOEXCEPT : file_(p.file) {}
-
-  // A "move constructor" for moving from an lvalue.
-  buffered_file(buffered_file &f) FMT_NOEXCEPT : file_(f.file_) {
-    f.file_ = FMT_NULL;
-  }
-
-  // A "move assignment operator" for moving from a temporary.
-  buffered_file &operator=(Proxy p) {
-    close();
-    file_ = p.file;
-    return *this;
-  }
-
-  // A "move assignment operator" for moving from an lvalue.
-  buffered_file &operator=(buffered_file &other) {
-    close();
-    file_ = other.file_;
-    other.file_ = FMT_NULL;
-    return *this;
-  }
-
-  // Returns a proxy object for moving from a temporary:
-  //   buffered_file file = buffered_file(...);
-  operator Proxy() FMT_NOEXCEPT {
-    Proxy p = {file_};
-    file_ = FMT_NULL;
-    return p;
-  }
-
-#else
- private:
-  FMT_DISALLOW_COPY_AND_ASSIGN(buffered_file);
-
- public:
-  buffered_file(buffered_file &&other) FMT_NOEXCEPT : file_(other.file_) {
-    other.file_ = FMT_NULL;
-  }
-
-  buffered_file& operator=(buffered_file &&other) {
-    close();
-    file_ = other.file_;
-    other.file_ = FMT_NULL;
-    return *this;
-  }
-#endif
-
-  // Opens a file.
-  FMT_API buffered_file(cstring_view filename, cstring_view mode);
-
-  // Closes the file.
-  FMT_API void close();
-
-  // Returns the pointer to a FILE object representing this file.
-  FILE *get() const FMT_NOEXCEPT { return file_; }
-
-  // We place parentheses around fileno to workaround a bug in some versions
-  // of MinGW that define fileno as a macro.
-  FMT_API int (fileno)() const;
-
-  void vprint(string_view format_str, format_args args) {
-    fmt::vprint(file_, format_str, args);
-  }
-
-  template <typename... Args>
-  inline void print(string_view format_str, const Args & ... args) {
-    vprint(format_str, make_format_args(args...));
-  }
-};
-
-// A file. Closed file is represented by a file object with descriptor -1.
-// Methods that are not declared with FMT_NOEXCEPT may throw
-// fmt::system_error in case of failure. Note that some errors such as
-// closing the file multiple times will cause a crash on Windows rather
-// than an exception. You can get standard behavior by overriding the
-// invalid parameter handler with _set_invalid_parameter_handler.
-class file {
- private:
-  int fd_;  // File descriptor.
-
-  // Constructs a file object with a given descriptor.
-  explicit file(int fd) : fd_(fd) {}
-
- public:
-  // Possible values for the oflag argument to the constructor.
-  enum {
-    RDONLY = FMT_POSIX(O_RDONLY), // Open for reading only.
-    WRONLY = FMT_POSIX(O_WRONLY), // Open for writing only.
-    RDWR   = FMT_POSIX(O_RDWR)    // Open for reading and writing.
-  };
-
-  // Constructs a file object which doesn't represent any file.
-  file() FMT_NOEXCEPT : fd_(-1) {}
-
-  // Opens a file and constructs a file object representing this file.
-  FMT_API file(cstring_view path, int oflag);
-
-#if !FMT_USE_RVALUE_REFERENCES
-  // Emulate a move constructor and a move assignment operator if rvalue
-  // references are not supported.
-
- private:
-  // A proxy object to emulate a move constructor.
-  // It is private to make it impossible call operator Proxy directly.
-  struct Proxy {
-    int fd;
-  };
-
- public:
-  // A "move constructor" for moving from a temporary.
-  file(Proxy p) FMT_NOEXCEPT : fd_(p.fd) {}
-
-  // A "move constructor" for moving from an lvalue.
-  file(file &other) FMT_NOEXCEPT : fd_(other.fd_) {
-    other.fd_ = -1;
-  }
-
-  // A "move assignment operator" for moving from a temporary.
-  file &operator=(Proxy p) {
-    close();
-    fd_ = p.fd;
-    return *this;
-  }
-
-  // A "move assignment operator" for moving from an lvalue.
-  file &operator=(file &other) {
-    close();
-    fd_ = other.fd_;
-    other.fd_ = -1;
-    return *this;
-  }
-
-  // Returns a proxy object for moving from a temporary:
-  //   file f = file(...);
-  operator Proxy() FMT_NOEXCEPT {
-    Proxy p = {fd_};
-    fd_ = -1;
-    return p;
-  }
-
-#else
- private:
-  FMT_DISALLOW_COPY_AND_ASSIGN(file);
-
- public:
-  file(file &&other) FMT_NOEXCEPT : fd_(other.fd_) {
-    other.fd_ = -1;
-  }
-
-  file& operator=(file &&other) {
-    close();
-    fd_ = other.fd_;
-    other.fd_ = -1;
-    return *this;
-  }
-#endif
-
-  // Destroys the object closing the file it represents if any.
-  FMT_API ~file() FMT_DTOR_NOEXCEPT;
-
-  // Returns the file descriptor.
-  int descriptor() const FMT_NOEXCEPT { return fd_; }
-
-  // Closes the file.
-  FMT_API void close();
-
-  // Returns the file size. The size has signed type for consistency with
-  // stat::st_size.
-  FMT_API long long size() const;
-
-  // Attempts to read count bytes from the file into the specified buffer.
-  FMT_API std::size_t read(void *buffer, std::size_t count);
-
-  // Attempts to write count bytes from the specified buffer to the file.
-  FMT_API std::size_t write(const void *buffer, std::size_t count);
-
-  // Duplicates a file descriptor with the dup function and returns
-  // the duplicate as a file object.
-  FMT_API static file dup(int fd);
-
-  // Makes fd be the copy of this file descriptor, closing fd first if
-  // necessary.
-  FMT_API void dup2(int fd);
-
-  // Makes fd be the copy of this file descriptor, closing fd first if
-  // necessary.
-  FMT_API void dup2(int fd, error_code &ec) FMT_NOEXCEPT;
-
-  // Creates a pipe setting up read_end and write_end file objects for reading
-  // and writing respectively.
-  FMT_API static void pipe(file &read_end, file &write_end);
-
-  // Creates a buffered_file object associated with this file and detaches
-  // this file object from the file.
-  FMT_API buffered_file fdopen(const char *mode);
-};
-
-// Returns the memory page size.
-long getpagesize();
-
-#if (defined(LC_NUMERIC_MASK) || defined(_MSC_VER)) && \
-    !defined(__ANDROID__) && !defined(__CYGWIN__) && !defined(__OpenBSD__)
-# define FMT_LOCALE
-#endif
-
-#ifdef FMT_LOCALE
-// A "C" numeric locale.
-class Locale {
- private:
-# ifdef _MSC_VER
-  typedef _locale_t locale_t;
-
-  enum { LC_NUMERIC_MASK = LC_NUMERIC };
-
-  static locale_t newlocale(int category_mask, const char *locale, locale_t) {
-    return _create_locale(category_mask, locale);
-  }
-
-  static void freelocale(locale_t locale) {
-    _free_locale(locale);
-  }
-
-  static double strtod_l(const char *nptr, char **endptr, _locale_t locale) {
-    return _strtod_l(nptr, endptr, locale);
-  }
-# endif
-
-  locale_t locale_;
-
-  FMT_DISALLOW_COPY_AND_ASSIGN(Locale);
-
- public:
-  typedef locale_t Type;
-
-  Locale() : locale_(newlocale(LC_NUMERIC_MASK, "C", FMT_NULL)) {
-    if (!locale_)
-      FMT_THROW(system_error(errno, "cannot create locale"));
-  }
-  ~Locale() { freelocale(locale_); }
-
-  Type get() const { return locale_; }
-
-  // Converts string to floating-point number and advances str past the end
-  // of the parsed input.
-  double strtod(const char *&str) const {
-    char *end = FMT_NULL;
-    double result = strtod_l(str, &end, locale_);
-    str = end;
-    return result;
-  }
-};
-#endif  // FMT_LOCALE
-FMT_END_NAMESPACE
-
-#if !FMT_USE_RVALUE_REFERENCES
-namespace std {
-// For compatibility with C++98.
-inline fmt::buffered_file &move(fmt::buffered_file &f) { return f; }
-inline fmt::file &move(fmt::file &f) { return f; }
-}
-#endif
-
-#endif  // FMT_POSIX_H_

include/fmt/ranges.h

@@ -1,243 +1,738 @@
-// Formatting library for C++ - the core API
+// Formatting library for C++ - range and tuple support
 //
-// Copyright (c) 2012 - present, Victor Zverovich
+// Copyright (c) 2012 - present, Victor Zverovich and {fmt} contributors
 // All rights reserved.
 //
 // For the license information refer to format.h.
-//
-// Copyright (c) 2018 - present, Remotion (Igor Schulz)
-// All Rights Reserved
-// {fmt} support for ranges, containers and types tuple interface.
 
 #ifndef FMT_RANGES_H_
 #define FMT_RANGES_H_
 
-#include "format.h"
+#include <initializer_list>
+#include <tuple>
 #include <type_traits>
 
-// output only up to N items from the range.
-#ifndef FMT_RANGE_OUTPUT_LENGTH_LIMIT
-# define FMT_RANGE_OUTPUT_LENGTH_LIMIT 256
-#endif
+#include "format.h"
 
 FMT_BEGIN_NAMESPACE
 
-template <typename Char>
-struct formatting_base {
-  template <typename ParseContext>
-  FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
-    return ctx.begin();
-  }
-};
+namespace detail {
 
-template <typename Char, typename Enable = void>
-struct formatting_range : formatting_base<Char> {
-  static FMT_CONSTEXPR_DECL const std::size_t range_length_limit =
-      FMT_RANGE_OUTPUT_LENGTH_LIMIT; // output only up to N items from the range.
-  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 internal {
-
-template <typename RangeT, typename OutputIterator>
-void copy(const RangeT &range, OutputIterator out) {
+template <typename Range, typename OutputIt>
+auto copy(const Range& range, OutputIt out) -> OutputIt {
   for (auto it = range.begin(), end = range.end(); it != end; ++it)
     *out++ = *it;
+  return out;
 }
 
-template <typename OutputIterator>
-void copy(const char *str, OutputIterator out) {
-  const char *p_curr = str;
-  while (*p_curr) {
-    *out++ = *p_curr++;
-  }
+template <typename OutputIt>
+auto copy(const char* str, OutputIt out) -> OutputIt {
+  while (*str) *out++ = *str++;
+  return out;
 }
 
-template <typename OutputIterator>
-void copy(char ch, OutputIterator out) {
+template <typename OutputIt> auto copy(char ch, OutputIt out) -> OutputIt {
   *out++ = ch;
+  return out;
 }
 
-/// Return true value if T has std::string interface, like std::string_view.
-template <typename T>
-class is_like_std_string {
+template <typename OutputIt> auto copy(wchar_t ch, OutputIt out) -> OutputIt {
+  *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(p->find('a'), p->length(), p->data(), int());
-  template <typename>
-  static void check(...);
+  static auto check(U* p)
+      -> decltype((void)p->find('a'), p->length(), (void)p->data(), int());
+  template <typename> static void check(...);
 
  public:
-  static FMT_CONSTEXPR_DECL const bool value =
-    !std::is_void<decltype(check<T>(FMT_NULL))>::value;
+  static constexpr const bool value =
+      is_string<T>::value ||
+      std::is_convertible<T, std_string_view<char>>::value ||
+      !std::is_void<decltype(check<T>(nullptr))>::value;
 };
 
-template <typename... Ts>
-struct conditional_helper {};
+template <typename Char>
+struct is_std_string_like<fmt::basic_string_view<Char>> : std::true_type {};
 
-template <typename T, typename _ = void>
-struct is_range_ : std::false_type {};
-
-template <typename T>
-struct is_range_<T,typename std::conditional<
-                   false,
-                   conditional_helper<decltype(internal::declval<T>().begin()),
-                                      decltype(internal::declval<T>().end())>,
-                   void>::type> : std::true_type {};
-
-template <typename T>
-struct is_range {
-  static FMT_CONSTEXPR_DECL const bool value =
-    is_range_<T>::value && !is_like_std_string<T>::value;
-};
-
-/// 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,
-      internal::declval<typename std::tuple_element<0, U>::type>(), int());
-  template <typename>
-  static void check(...);
+template <typename T> class is_map {
+  template <typename U> static auto check(U*) -> typename U::mapped_type;
+  template <typename> static void check(...);
 
  public:
-  static FMT_CONSTEXPR_DECL const bool value =
-    !std::is_void<decltype(check<T>(FMT_NULL))>::value;
-};
-
-template <typename T>
-struct is_tuple_like {
-  static FMT_CONSTEXPR_DECL const bool value =
-    is_tuple_like_<T>::value && !is_range_<T>::value;
-};
-}  // namespace internal
-
-#if FMT_HAS_FEATURE(__cpp_lib_integer_sequence) || FMT_MSC_VER >= 1900
-# define FMT_USE_INTEGER_SEQUENCE 1
+#ifdef FMT_FORMAT_MAP_AS_LIST  // DEPRECATED!
+  static constexpr const bool value = false;
 #else
-# define FMT_USE_INTEGER_SEQUENCE 0
+  static constexpr 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  // DEPRECATED!
+  static constexpr const bool value = false;
+#else
+  static constexpr 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_VERSION || FMT_MSC_VERSION > 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 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>())),
+              // the extra int here is because older versions of MSVC don't
+              // SFINAE properly unless there are distinct types
+              int>> : 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
 
-#if FMT_USE_INTEGER_SEQUENCE
-namespace internal {
-template <size_t... Is, class Tuple, class F>
-void for_each(std::index_sequence<Is...>, Tuple &&tup, F &&f) noexcept {
-  using std::get;
-  // using free function get<I>(T) now.
-  const int _[] = {0, ((void)f(get<Is>(tup)), 0)...};
-  (void)_;  // blocks warnings
-}
+// 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());
+  template <typename> static void check(...);
 
-template <class T>
-FMT_CONSTEXPR std::make_index_sequence<std::tuple_size<T>::value> 
-get_indexes(T const &) { return {}; }
-
-template <class Tuple, class F>
-void for_each(Tuple &&tup, F &&f) {
-  const auto indexes = get_indexes(tup);
-  for_each(indexes, std::forward<Tuple>(tup), std::forward<F>(f));
-}
-}  // namespace internal
-
-template <typename TupleT, typename Char>
-struct formatter<TupleT, Char, 
-    typename std::enable_if<fmt::internal::is_tuple_like<TupleT>::value>::type> {
-
-  fmt::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();
-    std::size_t i = 0;
-    internal::copy(formatting.prefix, out);
-    internal::for_each(values, [&](const auto &v) {
-      if (i > 0) {
-        if (formatting.add_prepostfix_space) {
-          *out++ = ' ';
-        }
-        internal::copy(formatting.delimiter, out);
-      }
-      if (formatting.add_delimiter_spaces && i > 0) {
-        format_to(out, " {}", v);
-      } else {
-        format_to(out, "{}", v);
-      }
-      ++i;
-    });
-    if (formatting.add_prepostfix_space) {
-      *out++ = ' ';
-    }
-    internal::copy(formatting.postfix, out);
-
-    return ctx.out();
-  }
+ public:
+  static constexpr const bool value =
+      !std::is_void<decltype(check<T>(nullptr))>::value;
 };
-#endif  // FMT_USE_INTEGER_SEQUENCE
 
-template <typename RangeT, typename Char>
-struct formatter< RangeT, Char,
-    typename std::enable_if<fmt::internal::is_range<RangeT>::value>::type> {
+// Check for integer_sequence
+#if defined(__cpp_lib_integer_sequence) || FMT_MSC_VERSION >= 1900
+template <typename T, T... N>
+using integer_sequence = std::integer_sequence<T, N...>;
+template <size_t... N> using index_sequence = std::index_sequence<N...>;
+template <size_t N> using make_index_sequence = std::make_index_sequence<N>;
+#else
+template <typename T, T... N> struct integer_sequence {
+  using value_type = T;
 
-  fmt::formatting_range<Char> formatting;
+  static FMT_CONSTEXPR auto size() -> size_t { return sizeof...(N); }
+};
+
+template <size_t... N> using index_sequence = integer_sequence<size_t, N...>;
+
+template <typename T, size_t N, T... Ns>
+struct make_integer_sequence : make_integer_sequence<T, N - 1, N - 1, Ns...> {};
+template <typename T, T... Ns>
+struct make_integer_sequence<T, 0, Ns...> : integer_sequence<T, Ns...> {};
+
+template <size_t N>
+using make_index_sequence = make_integer_sequence<size_t, N>;
+#endif
+
+template <typename T>
+using tuple_index_sequence = make_index_sequence<std::tuple_size<T>::value>;
+
+template <typename T, typename C, bool = is_tuple_like_<T>::value>
+class is_tuple_formattable_ {
+ public:
+  static constexpr const bool value = false;
+};
+template <typename T, typename C> class is_tuple_formattable_<T, C, true> {
+  template <std::size_t... Is>
+  static auto check2(index_sequence<Is...>,
+                     integer_sequence<bool, (Is == Is)...>) -> std::true_type;
+  static auto check2(...) -> std::false_type;
+  template <std::size_t... Is>
+  static auto check(index_sequence<Is...>) -> decltype(check2(
+      index_sequence<Is...>{},
+      integer_sequence<bool,
+                       (is_formattable<typename std::tuple_element<Is, T>::type,
+                                       C>::value)...>{}));
+
+ public:
+  static constexpr const bool value =
+      decltype(check(tuple_index_sequence<T>{}))::value;
+};
+
+template <typename Tuple, typename F, size_t... Is>
+FMT_CONSTEXPR void for_each(index_sequence<Is...>, Tuple&& t, F&& f) {
+  using std::get;
+  // Using a free function get<Is>(Tuple) now.
+  const int unused[] = {0, ((void)f(get<Is>(t)), 0)...};
+  ignore_unused(unused);
+}
+
+template <typename Tuple, typename F>
+FMT_CONSTEXPR void for_each(Tuple&& t, F&& f) {
+  for_each(tuple_index_sequence<remove_cvref_t<Tuple>>(),
+           std::forward<Tuple>(t), std::forward<F>(f));
+}
+
+template <typename Tuple1, typename Tuple2, typename F, size_t... Is>
+void for_each2(index_sequence<Is...>, Tuple1&& t1, Tuple2&& t2, F&& f) {
+  using std::get;
+  const int unused[] = {0, ((void)f(get<Is>(t1), get<Is>(t2)), 0)...};
+  ignore_unused(unused);
+}
+
+template <typename Tuple1, typename Tuple2, typename F>
+void for_each2(Tuple1&& t1, Tuple2&& t2, F&& f) {
+  for_each2(tuple_index_sequence<remove_cvref_t<Tuple1>>(),
+            std::forward<Tuple1>(t1), std::forward<Tuple2>(t2),
+            std::forward<F>(f));
+}
+
+namespace tuple {
+// Workaround a bug in MSVC 2019 (v140).
+template <typename Char, typename... T>
+using result_t = std::tuple<formatter<remove_cvref_t<T>, Char>...>;
+
+using std::get;
+template <typename Tuple, typename Char, std::size_t... Is>
+auto get_formatters(index_sequence<Is...>)
+    -> result_t<Char, decltype(get<Is>(std::declval<Tuple>()))...>;
+}  // namespace tuple
+
+#if FMT_MSC_VERSION && FMT_MSC_VERSION < 1920
+// Older MSVC doesn't get the reference type correctly for arrays.
+template <typename R> struct range_reference_type_impl {
+  using type = decltype(*detail::range_begin(std::declval<R&>()));
+};
+
+template <typename T, std::size_t N> struct range_reference_type_impl<T[N]> {
+  using type = T&;
+};
+
+template <typename T>
+using range_reference_type = typename range_reference_type_impl<T>::type;
+#else
+template <typename Range>
+using range_reference_type =
+    decltype(*detail::range_begin(std::declval<Range&>()));
+#endif
+
+// We don't use the Range's value_type for anything, but we do need the Range's
+// reference type, with cv-ref stripped.
+template <typename Range>
+using uncvref_type = remove_cvref_t<range_reference_type<Range>>;
+
+template <typename Formatter>
+FMT_CONSTEXPR auto maybe_set_debug_format(Formatter& f, bool set)
+    -> decltype(f.set_debug_format(set)) {
+  f.set_debug_format(set);
+}
+template <typename Formatter>
+FMT_CONSTEXPR void maybe_set_debug_format(Formatter&, ...) {}
+
+// These are not generic lambdas for compatibility with C++11.
+template <typename ParseContext> struct parse_empty_specs {
+  template <typename Formatter> FMT_CONSTEXPR void operator()(Formatter& f) {
+    f.parse(ctx);
+    detail::maybe_set_debug_format(f, true);
+  }
+  ParseContext& ctx;
+};
+template <typename FormatContext> struct format_tuple_element {
+  using char_type = typename FormatContext::char_type;
+
+  template <typename T>
+  void operator()(const formatter<T, char_type>& f, const T& v) {
+    if (i > 0)
+      ctx.advance_to(detail::copy_str<char_type>(separator, ctx.out()));
+    ctx.advance_to(f.format(v, ctx));
+    ++i;
+  }
+
+  int i;
+  FormatContext& ctx;
+  basic_string_view<char_type> separator;
+};
+
+}  // namespace detail
+
+template <typename T> struct is_tuple_like {
+  static constexpr const bool value =
+      detail::is_tuple_like_<T>::value && !detail::is_range_<T>::value;
+};
+
+template <typename T, typename C> struct is_tuple_formattable {
+  static constexpr const bool value =
+      detail::is_tuple_formattable_<T, C>::value;
+};
+
+template <typename Tuple, typename Char>
+struct formatter<Tuple, Char,
+                 enable_if_t<fmt::is_tuple_like<Tuple>::value &&
+                             fmt::is_tuple_formattable<Tuple, Char>::value>> {
+ private:
+  decltype(detail::tuple::get_formatters<Tuple, Char>(
+      detail::tuple_index_sequence<Tuple>())) formatters_;
+
+  basic_string_view<Char> separator_ = detail::string_literal<Char, ',', ' '>{};
+  basic_string_view<Char> opening_bracket_ =
+      detail::string_literal<Char, '('>{};
+  basic_string_view<Char> closing_bracket_ =
+      detail::string_literal<Char, ')'>{};
+
+ public:
+  FMT_CONSTEXPR formatter() {}
+
+  FMT_CONSTEXPR void set_separator(basic_string_view<Char> sep) {
+    separator_ = sep;
+  }
+
+  FMT_CONSTEXPR void set_brackets(basic_string_view<Char> open,
+                                  basic_string_view<Char> close) {
+    opening_bracket_ = open;
+    closing_bracket_ = close;
+  }
 
   template <typename ParseContext>
-  FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
-    return formatting.parse(ctx);
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    auto it = ctx.begin();
+    if (it != ctx.end() && *it != '}')
+      FMT_THROW(format_error("invalid format specifier"));
+    detail::for_each(formatters_, detail::parse_empty_specs<ParseContext>{ctx});
+    return it;
   }
 
   template <typename FormatContext>
-  typename FormatContext::iterator format(
-      const RangeT &values, FormatContext &ctx) {
-    auto out = ctx.out();
-    internal::copy(formatting.prefix, out);
-    std::size_t i = 0;
-    for (auto it = values.begin(), end = values.end(); it != end; ++it) {
-      if (i > 0) {
-        if (formatting.add_prepostfix_space) {
-          *out++ = ' ';
-        }
-        internal::copy(formatting.delimiter, out);
-      }
-      if (formatting.add_delimiter_spaces && i > 0) {
-        format_to(out, " {}", *it);
-      } else {
-        format_to(out, "{}", *it);
-      }
-      if (++i > formatting.range_length_limit) {
-        format_to(out, " ... <other elements>");
-        break;
-      }
-    }
-    if (formatting.add_prepostfix_space) {
-      *out++ = ' ';
-    }
-    internal::copy(formatting.postfix, out);
-    return ctx.out();
+  auto format(const Tuple& value, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    ctx.advance_to(detail::copy_str<Char>(opening_bracket_, ctx.out()));
+    detail::for_each2(
+        formatters_, value,
+        detail::format_tuple_element<FormatContext>{0, ctx, separator_});
+    return detail::copy_str<Char>(closing_bracket_, ctx.out());
   }
 };
 
+template <typename T, typename Char> struct is_range {
+  static constexpr const bool value =
+      detail::is_range_<T>::value && !detail::is_std_string_like<T>::value &&
+      !std::is_convertible<T, std::basic_string<Char>>::value &&
+      !std::is_convertible<T, detail::std_string_view<Char>>::value;
+};
+
+namespace detail {
+template <typename Context> struct range_mapper {
+  using mapper = arg_mapper<Context>;
+
+  template <typename T,
+            FMT_ENABLE_IF(has_formatter<remove_cvref_t<T>, Context>::value)>
+  static auto map(T&& value) -> T&& {
+    return static_cast<T&&>(value);
+  }
+  template <typename T,
+            FMT_ENABLE_IF(!has_formatter<remove_cvref_t<T>, Context>::value)>
+  static auto map(T&& value)
+      -> decltype(mapper().map(static_cast<T&&>(value))) {
+    return mapper().map(static_cast<T&&>(value));
+  }
+};
+
+template <typename Char, typename Element>
+using range_formatter_type =
+    formatter<remove_cvref_t<decltype(range_mapper<buffer_context<Char>>{}.map(
+                  std::declval<Element>()))>,
+              Char>;
+
+template <typename R>
+using maybe_const_range =
+    conditional_t<has_const_begin_end<R>::value, const R, R>;
+
+// Workaround a bug in MSVC 2015 and earlier.
+#if !FMT_MSC_VERSION || FMT_MSC_VERSION >= 1910
+template <typename R, typename Char>
+struct is_formattable_delayed
+    : is_formattable<uncvref_type<maybe_const_range<R>>, Char> {};
+#endif
+}  // namespace detail
+
+template <typename...> struct conjunction : std::true_type {};
+template <typename P> struct conjunction<P> : P {};
+template <typename P1, typename... Pn>
+struct conjunction<P1, Pn...>
+    : conditional_t<bool(P1::value), conjunction<Pn...>, P1> {};
+
+template <typename T, typename Char, typename Enable = void>
+struct range_formatter;
+
+template <typename T, typename Char>
+struct range_formatter<
+    T, Char,
+    enable_if_t<conjunction<std::is_same<T, remove_cvref_t<T>>,
+                            is_formattable<T, Char>>::value>> {
+ private:
+  detail::range_formatter_type<Char, T> underlying_;
+  basic_string_view<Char> separator_ = detail::string_literal<Char, ',', ' '>{};
+  basic_string_view<Char> opening_bracket_ =
+      detail::string_literal<Char, '['>{};
+  basic_string_view<Char> closing_bracket_ =
+      detail::string_literal<Char, ']'>{};
+
+ public:
+  FMT_CONSTEXPR range_formatter() {}
+
+  FMT_CONSTEXPR auto underlying() -> detail::range_formatter_type<Char, T>& {
+    return underlying_;
+  }
+
+  FMT_CONSTEXPR void set_separator(basic_string_view<Char> sep) {
+    separator_ = sep;
+  }
+
+  FMT_CONSTEXPR void set_brackets(basic_string_view<Char> open,
+                                  basic_string_view<Char> close) {
+    opening_bracket_ = open;
+    closing_bracket_ = close;
+  }
+
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    auto it = ctx.begin();
+    auto end = ctx.end();
+
+    if (it != end && *it == 'n') {
+      set_brackets({}, {});
+      ++it;
+    }
+
+    if (it != end && *it != '}') {
+      if (*it != ':') FMT_THROW(format_error("invalid format specifier"));
+      ++it;
+    } else {
+      detail::maybe_set_debug_format(underlying_, true);
+    }
+
+    ctx.advance_to(it);
+    return underlying_.parse(ctx);
+  }
+
+  template <typename R, typename FormatContext>
+  auto format(R&& range, FormatContext& ctx) const -> decltype(ctx.out()) {
+    detail::range_mapper<buffer_context<Char>> mapper;
+    auto out = ctx.out();
+    out = detail::copy_str<Char>(opening_bracket_, out);
+    int i = 0;
+    auto it = detail::range_begin(range);
+    auto end = detail::range_end(range);
+    for (; it != end; ++it) {
+      if (i > 0) out = detail::copy_str<Char>(separator_, out);
+      ctx.advance_to(out);
+      auto&& item = *it;
+      out = underlying_.format(mapper.map(item), ctx);
+      ++i;
+    }
+    out = detail::copy_str<Char>(closing_bracket_, out);
+    return out;
+  }
+};
+
+enum class range_format { disabled, map, set, sequence, string, debug_string };
+
+namespace detail {
+template <typename T>
+struct range_format_kind_
+    : std::integral_constant<range_format,
+                             std::is_same<uncvref_type<T>, T>::value
+                                 ? range_format::disabled
+                             : is_map<T>::value ? range_format::map
+                             : is_set<T>::value ? range_format::set
+                                                : range_format::sequence> {};
+
+template <range_format K, typename R, typename Char, typename Enable = void>
+struct range_default_formatter;
+
+template <range_format K>
+using range_format_constant = std::integral_constant<range_format, K>;
+
+template <range_format K, typename R, typename Char>
+struct range_default_formatter<
+    K, R, Char,
+    enable_if_t<(K == range_format::sequence || K == range_format::map ||
+                 K == range_format::set)>> {
+  using range_type = detail::maybe_const_range<R>;
+  range_formatter<detail::uncvref_type<range_type>, Char> underlying_;
+
+  FMT_CONSTEXPR range_default_formatter() { init(range_format_constant<K>()); }
+
+  FMT_CONSTEXPR void init(range_format_constant<range_format::set>) {
+    underlying_.set_brackets(detail::string_literal<Char, '{'>{},
+                             detail::string_literal<Char, '}'>{});
+  }
+
+  FMT_CONSTEXPR void init(range_format_constant<range_format::map>) {
+    underlying_.set_brackets(detail::string_literal<Char, '{'>{},
+                             detail::string_literal<Char, '}'>{});
+    underlying_.underlying().set_brackets({}, {});
+    underlying_.underlying().set_separator(
+        detail::string_literal<Char, ':', ' '>{});
+  }
+
+  FMT_CONSTEXPR void init(range_format_constant<range_format::sequence>) {}
+
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return underlying_.parse(ctx);
+  }
+
+  template <typename FormatContext>
+  auto format(range_type& range, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return underlying_.format(range, ctx);
+  }
+};
+}  // namespace detail
+
+template <typename T, typename Char, typename Enable = void>
+struct range_format_kind
+    : conditional_t<
+          is_range<T, Char>::value, detail::range_format_kind_<T>,
+          std::integral_constant<range_format, range_format::disabled>> {};
+
+template <typename R, typename Char>
+struct formatter<
+    R, Char,
+    enable_if_t<conjunction<bool_constant<range_format_kind<R, Char>::value !=
+                                          range_format::disabled>
+// Workaround a bug in MSVC 2015 and earlier.
+#if !FMT_MSC_VERSION || FMT_MSC_VERSION >= 1910
+                            ,
+                            detail::is_formattable_delayed<R, Char>
+#endif
+                            >::value>>
+    : detail::range_default_formatter<range_format_kind<R, Char>::value, R,
+                                      Char> {
+};
+
+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} {}
+};
+
+// 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>
+  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:
+  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>
+  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, 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 do_format(value, ctx, std::integral_constant<size_t, N - 1>());
+    }
+    return out;
+  }
+};
+
+namespace detail {
+// Check if T has an interface like a container adaptor (e.g. std::stack,
+// std::queue, std::priority_queue).
+template <typename T> class is_container_adaptor_like {
+  template <typename U> static auto check(U* p) -> typename U::container_type;
+  template <typename> static void check(...);
+
+ public:
+  static constexpr const bool value =
+      !std::is_void<decltype(check<T>(nullptr))>::value;
+};
+
+template <typename Container> struct all {
+  const Container& c;
+  auto begin() const -> typename Container::const_iterator { return c.begin(); }
+  auto end() const -> typename Container::const_iterator { return c.end(); }
+};
+}  // namespace detail
+
+template <typename T, typename Char>
+struct formatter<
+    T, Char,
+    enable_if_t<conjunction<detail::is_container_adaptor_like<T>,
+                            bool_constant<range_format_kind<T, Char>::value ==
+                                          range_format::disabled>>::value>>
+    : formatter<detail::all<typename T::container_type>, Char> {
+  using all = detail::all<typename T::container_type>;
+  template <typename FormatContext>
+  auto format(const T& t, FormatContext& ctx) const -> decltype(ctx.out()) {
+    struct getter : T {
+      static auto get(const T& t) -> all {
+        return {t.*(&getter::c)};  // Access c through the derived class.
+      }
+    };
+    return formatter<all>::format(getter::get(t), ctx);
+  }
+};
+
+FMT_BEGIN_EXPORT
+
+/**
+  \rst
+  Returns an object that formats `tuple` with elements separated by `sep`.
+
+  **Example**::
+
+    std::tuple<int, char> t = {1, 'a'};
+    fmt::print("{}", fmt::join(t, ", "));
+    // Output: "1, a"
+  \endrst
+ */
+template <typename... T>
+FMT_CONSTEXPR auto join(const std::tuple<T...>& tuple, string_view sep)
+    -> tuple_join_view<char, T...> {
+  return {tuple, sep};
+}
+
+template <typename... T>
+FMT_CONSTEXPR auto join(const std::tuple<T...>& tuple,
+                        basic_string_view<wchar_t> sep)
+    -> tuple_join_view<wchar_t, T...> {
+  return {tuple, sep};
+}
+
+/**
+  \rst
+  Returns an object that formats `initializer_list` with elements separated by
+  `sep`.
+
+  **Example**::
+
+    fmt::print("{}", fmt::join({1, 2, 3}, ", "));
+    // Output: "1, 2, 3"
+  \endrst
+ */
+template <typename T>
+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_END_EXPORT
 FMT_END_NAMESPACE
 
-#endif // FMT_RANGES_H_
-
+#endif  // FMT_RANGES_H_

include/fmt/std.h

@@ -0,0 +1,537 @@
+// Formatting library for C++ - formatters for standard library types
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_STD_H_
+#define FMT_STD_H_
+
+#include <atomic>
+#include <bitset>
+#include <cstdlib>
+#include <exception>
+#include <memory>
+#include <thread>
+#include <type_traits>
+#include <typeinfo>
+#include <utility>
+#include <vector>
+
+#include "format.h"
+#include "ostream.h"
+
+#if FMT_HAS_INCLUDE(<version>)
+#  include <version>
+#endif
+// Checking FMT_CPLUSPLUS for warning suppression in MSVC.
+#if FMT_CPLUSPLUS >= 201703L
+#  if FMT_HAS_INCLUDE(<filesystem>)
+#    include <filesystem>
+#  endif
+#  if FMT_HAS_INCLUDE(<variant>)
+#    include <variant>
+#  endif
+#  if FMT_HAS_INCLUDE(<optional>)
+#    include <optional>
+#  endif
+#endif
+
+#if FMT_CPLUSPLUS > 201703L && FMT_HAS_INCLUDE(<source_location>)
+#  include <source_location>
+#endif
+
+// GCC 4 does not support FMT_HAS_INCLUDE.
+#if FMT_HAS_INCLUDE(<cxxabi.h>) || defined(__GLIBCXX__)
+#  include <cxxabi.h>
+// Android NDK with gabi++ library on some architectures does not implement
+// abi::__cxa_demangle().
+#  ifndef __GABIXX_CXXABI_H__
+#    define FMT_HAS_ABI_CXA_DEMANGLE
+#  endif
+#endif
+
+// Check if typeid is available.
+#ifndef FMT_USE_TYPEID
+// __RTTI is for EDG compilers. In MSVC typeid is available without RTTI.
+#  if defined(__GXX_RTTI) || FMT_HAS_FEATURE(cxx_rtti) || FMT_MSC_VERSION || \
+      defined(__INTEL_RTTI__) || defined(__RTTI)
+#    define FMT_USE_TYPEID 1
+#  else
+#    define FMT_USE_TYPEID 0
+#  endif
+#endif
+
+// For older Xcode versions, __cpp_lib_xxx flags are inaccurately defined.
+#ifndef FMT_CPP_LIB_FILESYSTEM
+#  ifdef __cpp_lib_filesystem
+#    define FMT_CPP_LIB_FILESYSTEM __cpp_lib_filesystem
+#  else
+#    define FMT_CPP_LIB_FILESYSTEM 0
+#  endif
+#endif
+
+#ifndef FMT_CPP_LIB_VARIANT
+#  ifdef __cpp_lib_variant
+#    define FMT_CPP_LIB_VARIANT __cpp_lib_variant
+#  else
+#    define FMT_CPP_LIB_VARIANT 0
+#  endif
+#endif
+
+#if FMT_CPP_LIB_FILESYSTEM
+FMT_BEGIN_NAMESPACE
+
+namespace detail {
+
+template <typename Char, typename PathChar>
+auto get_path_string(const std::filesystem::path& p,
+                     const std::basic_string<PathChar>& native) {
+  if constexpr (std::is_same_v<Char, char> && std::is_same_v<PathChar, wchar_t>)
+    return to_utf8<wchar_t>(native, to_utf8_error_policy::replace);
+  else
+    return p.string<Char>();
+}
+
+template <typename Char, typename PathChar>
+void write_escaped_path(basic_memory_buffer<Char>& quoted,
+                        const std::filesystem::path& p,
+                        const std::basic_string<PathChar>& native) {
+  if constexpr (std::is_same_v<Char, char> &&
+                std::is_same_v<PathChar, wchar_t>) {
+    auto buf = basic_memory_buffer<wchar_t>();
+    write_escaped_string<wchar_t>(std::back_inserter(buf), native);
+    bool valid = to_utf8<wchar_t>::convert(quoted, {buf.data(), buf.size()});
+    FMT_ASSERT(valid, "invalid utf16");
+  } else if constexpr (std::is_same_v<Char, PathChar>) {
+    write_escaped_string<std::filesystem::path::value_type>(
+        std::back_inserter(quoted), native);
+  } else {
+    write_escaped_string<Char>(std::back_inserter(quoted), p.string<Char>());
+  }
+}
+
+}  // namespace detail
+
+FMT_EXPORT
+template <typename Char> struct formatter<std::filesystem::path, Char> {
+ private:
+  format_specs<Char> specs_;
+  detail::arg_ref<Char> width_ref_;
+  bool debug_ = false;
+  char path_type_ = 0;
+
+ public:
+  FMT_CONSTEXPR void set_debug_format(bool set = true) { debug_ = set; }
+
+  template <typename ParseContext> FMT_CONSTEXPR auto parse(ParseContext& ctx) {
+    auto it = ctx.begin(), end = ctx.end();
+    if (it == end) return it;
+
+    it = detail::parse_align(it, end, specs_);
+    if (it == end) return it;
+
+    it = detail::parse_dynamic_spec(it, end, specs_.width, width_ref_, ctx);
+    if (it != end && *it == '?') {
+      debug_ = true;
+      ++it;
+    }
+    if (it != end && (*it == 'g')) path_type_ = *it++;
+    return it;
+  }
+
+  template <typename FormatContext>
+  auto format(const std::filesystem::path& p, FormatContext& ctx) const {
+    auto specs = specs_;
+#  ifdef _WIN32
+    auto path_string = !path_type_ ? p.native() : p.generic_wstring();
+#  else
+    auto path_string = !path_type_ ? p.native() : p.generic_string();
+#  endif
+
+    detail::handle_dynamic_spec<detail::width_checker>(specs.width, width_ref_,
+                                                       ctx);
+    if (!debug_) {
+      auto s = detail::get_path_string<Char>(p, path_string);
+      return detail::write(ctx.out(), basic_string_view<Char>(s), specs);
+    }
+    auto quoted = basic_memory_buffer<Char>();
+    detail::write_escaped_path(quoted, p, path_string);
+    return detail::write(ctx.out(),
+                         basic_string_view<Char>(quoted.data(), quoted.size()),
+                         specs);
+  }
+};
+FMT_END_NAMESPACE
+#endif  // FMT_CPP_LIB_FILESYSTEM
+
+FMT_BEGIN_NAMESPACE
+FMT_EXPORT
+template <std::size_t N, typename Char>
+struct formatter<std::bitset<N>, Char> : nested_formatter<string_view> {
+ private:
+  // Functor because C++11 doesn't support generic lambdas.
+  struct writer {
+    const std::bitset<N>& bs;
+
+    template <typename OutputIt>
+    FMT_CONSTEXPR auto operator()(OutputIt out) -> OutputIt {
+      for (auto pos = N; pos > 0; --pos) {
+        out = detail::write<Char>(out, bs[pos - 1] ? Char('1') : Char('0'));
+      }
+
+      return out;
+    }
+  };
+
+ public:
+  template <typename FormatContext>
+  auto format(const std::bitset<N>& bs, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return write_padded(ctx, writer{bs});
+  }
+};
+
+FMT_EXPORT
+template <typename Char>
+struct formatter<std::thread::id, Char> : basic_ostream_formatter<Char> {};
+FMT_END_NAMESPACE
+
+#ifdef __cpp_lib_optional
+FMT_BEGIN_NAMESPACE
+FMT_EXPORT
+template <typename T, typename Char>
+struct formatter<std::optional<T>, Char,
+                 std::enable_if_t<is_formattable<T, Char>::value>> {
+ private:
+  formatter<T, Char> underlying_;
+  static constexpr basic_string_view<Char> optional =
+      detail::string_literal<Char, 'o', 'p', 't', 'i', 'o', 'n', 'a', 'l',
+                             '('>{};
+  static constexpr basic_string_view<Char> none =
+      detail::string_literal<Char, 'n', 'o', 'n', 'e'>{};
+
+  template <class U>
+  FMT_CONSTEXPR static auto maybe_set_debug_format(U& u, bool set)
+      -> decltype(u.set_debug_format(set)) {
+    u.set_debug_format(set);
+  }
+
+  template <class U>
+  FMT_CONSTEXPR static void maybe_set_debug_format(U&, ...) {}
+
+ public:
+  template <typename ParseContext> FMT_CONSTEXPR auto parse(ParseContext& ctx) {
+    maybe_set_debug_format(underlying_, true);
+    return underlying_.parse(ctx);
+  }
+
+  template <typename FormatContext>
+  auto format(const std::optional<T>& opt, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    if (!opt) return detail::write<Char>(ctx.out(), none);
+
+    auto out = ctx.out();
+    out = detail::write<Char>(out, optional);
+    ctx.advance_to(out);
+    out = underlying_.format(*opt, ctx);
+    return detail::write(out, ')');
+  }
+};
+FMT_END_NAMESPACE
+#endif  // __cpp_lib_optional
+
+#ifdef __cpp_lib_source_location
+FMT_BEGIN_NAMESPACE
+FMT_EXPORT
+template <> struct formatter<std::source_location> {
+  template <typename ParseContext> FMT_CONSTEXPR auto parse(ParseContext& ctx) {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const std::source_location& loc, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+    out = detail::write(out, loc.file_name());
+    out = detail::write(out, ':');
+    out = detail::write<char>(out, loc.line());
+    out = detail::write(out, ':');
+    out = detail::write<char>(out, loc.column());
+    out = detail::write(out, ": ");
+    out = detail::write(out, loc.function_name());
+    return out;
+  }
+};
+FMT_END_NAMESPACE
+#endif
+
+#if FMT_CPP_LIB_VARIANT
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template <typename T>
+using variant_index_sequence =
+    std::make_index_sequence<std::variant_size<T>::value>;
+
+template <typename> struct is_variant_like_ : std::false_type {};
+template <typename... Types>
+struct is_variant_like_<std::variant<Types...>> : std::true_type {};
+
+// formattable element check.
+template <typename T, typename C> class is_variant_formattable_ {
+  template <std::size_t... Is>
+  static std::conjunction<
+      is_formattable<std::variant_alternative_t<Is, T>, C>...>
+      check(std::index_sequence<Is...>);
+
+ public:
+  static constexpr const bool value =
+      decltype(check(variant_index_sequence<T>{}))::value;
+};
+
+template <typename Char, typename OutputIt, typename T>
+auto write_variant_alternative(OutputIt out, const T& v) -> OutputIt {
+  if constexpr (is_string<T>::value)
+    return write_escaped_string<Char>(out, detail::to_string_view(v));
+  else if constexpr (std::is_same_v<T, Char>)
+    return write_escaped_char(out, v);
+  else
+    return write<Char>(out, v);
+}
+
+}  // namespace detail
+
+template <typename T> struct is_variant_like {
+  static constexpr const bool value = detail::is_variant_like_<T>::value;
+};
+
+template <typename T, typename C> struct is_variant_formattable {
+  static constexpr const bool value =
+      detail::is_variant_formattable_<T, C>::value;
+};
+
+FMT_EXPORT
+template <typename Char> struct formatter<std::monostate, Char> {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const std::monostate&, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return detail::write<Char>(ctx.out(), "monostate");
+  }
+};
+
+FMT_EXPORT
+template <typename Variant, typename Char>
+struct formatter<
+    Variant, Char,
+    std::enable_if_t<std::conjunction_v<
+        is_variant_like<Variant>, is_variant_formattable<Variant, Char>>>> {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const Variant& value, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+
+    out = detail::write<Char>(out, "variant(");
+    FMT_TRY {
+      std::visit(
+          [&](const auto& v) {
+            out = detail::write_variant_alternative<Char>(out, v);
+          },
+          value);
+    }
+    FMT_CATCH(const std::bad_variant_access&) {
+      detail::write<Char>(out, "valueless by exception");
+    }
+    *out++ = ')';
+    return out;
+  }
+};
+FMT_END_NAMESPACE
+#endif  // FMT_CPP_LIB_VARIANT
+
+FMT_BEGIN_NAMESPACE
+FMT_EXPORT
+template <typename Char> struct formatter<std::error_code, Char> {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  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(), format_specs<Char>());
+    out = detail::write<Char>(out, Char(':'));
+    out = detail::write<Char>(out, ec.value());
+    return out;
+  }
+};
+
+FMT_EXPORT
+template <typename T, typename Char>
+struct formatter<
+    T, Char,  // DEPRECATED! Mixing code unit types.
+    typename std::enable_if<std::is_base_of<std::exception, T>::value>::type> {
+ private:
+  bool with_typename_ = false;
+
+ public:
+  FMT_CONSTEXPR auto parse(basic_format_parse_context<Char>& ctx)
+      -> decltype(ctx.begin()) {
+    auto it = ctx.begin();
+    auto end = ctx.end();
+    if (it == end || *it == '}') return it;
+    if (*it == 't') {
+      ++it;
+      with_typename_ = FMT_USE_TYPEID != 0;
+    }
+    return it;
+  }
+
+  template <typename OutputIt>
+  auto format(const std::exception& ex,
+              basic_format_context<OutputIt, Char>& ctx) const -> OutputIt {
+    format_specs<Char> spec;
+    auto out = ctx.out();
+    if (!with_typename_)
+      return detail::write_bytes(out, string_view(ex.what()), spec);
+
+#if FMT_USE_TYPEID
+    const std::type_info& ti = typeid(ex);
+#  ifdef FMT_HAS_ABI_CXA_DEMANGLE
+    int status = 0;
+    std::size_t size = 0;
+    std::unique_ptr<char, void (*)(void*)> demangled_name_ptr(
+        abi::__cxa_demangle(ti.name(), nullptr, &size, &status), &std::free);
+
+    string_view demangled_name_view;
+    if (demangled_name_ptr) {
+      demangled_name_view = demangled_name_ptr.get();
+
+      // Normalization of stdlib inline namespace names.
+      // libc++ inline namespaces.
+      //  std::__1::*       -> std::*
+      //  std::__1::__fs::* -> std::*
+      // libstdc++ inline namespaces.
+      //  std::__cxx11::*             -> std::*
+      //  std::filesystem::__cxx11::* -> std::filesystem::*
+      if (demangled_name_view.starts_with("std::")) {
+        char* begin = demangled_name_ptr.get();
+        char* to = begin + 5;  // std::
+        for (char *from = to, *end = begin + demangled_name_view.size();
+             from < end;) {
+          // This is safe, because demangled_name is NUL-terminated.
+          if (from[0] == '_' && from[1] == '_') {
+            char* next = from + 1;
+            while (next < end && *next != ':') next++;
+            if (next[0] == ':' && next[1] == ':') {
+              from = next + 2;
+              continue;
+            }
+          }
+          *to++ = *from++;
+        }
+        demangled_name_view = {begin, detail::to_unsigned(to - begin)};
+      }
+    } else {
+      demangled_name_view = string_view(ti.name());
+    }
+    out = detail::write_bytes(out, demangled_name_view, spec);
+#  elif FMT_MSC_VERSION
+    string_view demangled_name_view(ti.name());
+    if (demangled_name_view.starts_with("class "))
+      demangled_name_view.remove_prefix(6);
+    else if (demangled_name_view.starts_with("struct "))
+      demangled_name_view.remove_prefix(7);
+    out = detail::write_bytes(out, demangled_name_view, spec);
+#  else
+    out = detail::write_bytes(out, string_view(ti.name()), spec);
+#  endif
+    *out++ = ':';
+    *out++ = ' ';
+    return detail::write_bytes(out, string_view(ex.what()), spec);
+#endif
+  }
+};
+
+namespace detail {
+
+template <typename T, typename Enable = void>
+struct has_flip : std::false_type {};
+
+template <typename T>
+struct has_flip<T, void_t<decltype(std::declval<T>().flip())>>
+    : std::true_type {};
+
+template <typename T> struct is_bit_reference_like {
+  static constexpr const bool value =
+      std::is_convertible<T, bool>::value &&
+      std::is_nothrow_assignable<T, bool>::value && has_flip<T>::value;
+};
+
+#ifdef _LIBCPP_VERSION
+
+// Workaround for libc++ incompatibility with C++ standard.
+// According to the Standard, `bitset::operator[] const` returns bool.
+template <typename C>
+struct is_bit_reference_like<std::__bit_const_reference<C>> {
+  static constexpr const bool value = true;
+};
+
+#endif
+
+}  // namespace detail
+
+// We can't use std::vector<bool, Allocator>::reference and
+// std::bitset<N>::reference because the compiler can't deduce Allocator and N
+// in partial specialization.
+FMT_EXPORT
+template <typename BitRef, typename Char>
+struct formatter<BitRef, Char,
+                 enable_if_t<detail::is_bit_reference_like<BitRef>::value>>
+    : formatter<bool, Char> {
+  template <typename FormatContext>
+  FMT_CONSTEXPR auto format(const BitRef& v, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<bool, Char>::format(v, ctx);
+  }
+};
+
+FMT_EXPORT
+template <typename T, typename Char>
+struct formatter<std::atomic<T>, Char,
+                 enable_if_t<is_formattable<T, Char>::value>>
+    : formatter<T, Char> {
+  template <typename FormatContext>
+  auto format(const std::atomic<T>& v, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<T, Char>::format(v.load(), ctx);
+  }
+};
+
+#ifdef __cpp_lib_atomic_flag_test
+FMT_EXPORT
+template <typename Char>
+struct formatter<std::atomic_flag, Char> : formatter<bool, Char> {
+  template <typename FormatContext>
+  auto format(const std::atomic_flag& v, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<bool, Char>::format(v.test(), ctx);
+  }
+};
+#endif  // __cpp_lib_atomic_flag_test
+
+FMT_END_NAMESPACE
+#endif  // FMT_STD_H_

include/fmt/time.h

@@ -1,154 +0,0 @@
-// Formatting library for C++ - time formatting
-//
-// Copyright (c) 2012 - 2016, Victor Zverovich
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-#ifndef FMT_TIME_H_
-#define FMT_TIME_H_
-
-#include "format.h"
-#include <ctime>
-
-FMT_BEGIN_NAMESPACE
-
-namespace internal{
-inline null<> localtime_r(...) { return null<>(); }
-inline null<> localtime_s(...) { return null<>(); }
-inline null<> gmtime_r(...) { return null<>(); }
-inline null<> gmtime_s(...) { return null<>(); }
-}
-
-// Thread-safe replacement for std::localtime
-inline std::tm localtime(std::time_t time) {
-  struct dispatcher {
-    std::time_t time_;
-    std::tm tm_;
-
-    dispatcher(std::time_t t): time_(t) {}
-
-    bool run() {
-      using namespace fmt::internal;
-      return handle(localtime_r(&time_, &tm_));
-    }
-
-    bool handle(std::tm *tm) { return tm != FMT_NULL; }
-
-    bool handle(internal::null<>) {
-      using namespace fmt::internal;
-      return fallback(localtime_s(&tm_, &time_));
-    }
-
-    bool fallback(int res) { return res == 0; }
-
-    bool fallback(internal::null<>) {
-      using namespace fmt::internal;
-      std::tm *tm = std::localtime(&time_);
-      if (tm) tm_ = *tm;
-      return tm != FMT_NULL;
-    }
-  };
-  dispatcher lt(time);
-  if (lt.run())
-    return lt.tm_;
-  // Too big time values may be unsupported.
-  FMT_THROW(format_error("time_t value out of range"));
-  return std::tm();
-}
-
-// Thread-safe replacement for std::gmtime
-inline std::tm gmtime(std::time_t time) {
-  struct dispatcher {
-    std::time_t time_;
-    std::tm tm_;
-
-    dispatcher(std::time_t t): time_(t) {}
-
-    bool run() {
-      using namespace fmt::internal;
-      return handle(gmtime_r(&time_, &tm_));
-    }
-
-    bool handle(std::tm *tm) { return tm != FMT_NULL; }
-
-    bool handle(internal::null<>) {
-      using namespace fmt::internal;
-      return fallback(gmtime_s(&tm_, &time_));
-    }
-
-    bool fallback(int res) { return res == 0; }
-
-    bool fallback(internal::null<>) {
-      std::tm *tm = std::gmtime(&time_);
-      if (tm) tm_ = *tm;
-      return tm != FMT_NULL;
-    }
-  };
-  dispatcher gt(time);
-  if (gt.run())
-    return gt.tm_;
-  // Too big time values may be unsupported.
-  FMT_THROW(format_error("time_t value out of range"));
-  return std::tm();
-}
-
-namespace internal {
-inline std::size_t strftime(char *str, std::size_t count, const char *format,
-                            const std::tm *time) {
-  return std::strftime(str, count, format, time);
-}
-
-inline std::size_t strftime(wchar_t *str, std::size_t count,
-                            const wchar_t *format, const std::tm *time) {
-  return std::wcsftime(str, count, format, time);
-}
-}
-
-template <typename Char>
-struct formatter<std::tm, Char> {
-  template <typename ParseContext>
-  auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
-    auto it = internal::null_terminating_iterator<Char>(ctx);
-    if (*it == ':')
-      ++it;
-    auto end = it;
-    while (*end && *end != '}')
-      ++end;
-    tm_format.reserve(end - it + 1);
-    using internal::pointer_from;
-    tm_format.append(pointer_from(it), pointer_from(end));
-    tm_format.push_back('\0');
-    return pointer_from(end);
-  }
-
-  template <typename FormatContext>
-  auto format(const std::tm &tm, FormatContext &ctx) -> decltype(ctx.out()) {
-    internal::basic_buffer<Char> &buf = internal::get_container(ctx.out());
-    std::size_t start = buf.size();
-    for (;;) {
-      std::size_t size = buf.capacity() - start;
-      std::size_t count =
-        internal::strftime(&buf[start], size, &tm_format[0], &tm);
-      if (count != 0) {
-        buf.resize(start + count);
-        break;
-      }
-      if (size >= tm_format.size() * 256) {
-        // If the buffer is 256 times larger than the format string, assume
-        // that `strftime` gives an empty result. There doesn't seem to be a
-        // better way to distinguish the two cases:
-        // https://github.com/fmtlib/fmt/issues/367
-        break;
-      }
-      const std::size_t MIN_GROWTH = 10;
-      buf.reserve(buf.capacity() + (size > MIN_GROWTH ? size : MIN_GROWTH));
-    }
-    return ctx.out();
-  }
-
-  basic_memory_buffer<Char> tm_format;
-};
-FMT_END_NAMESPACE
-
-#endif  // FMT_TIME_H_

include/fmt/xchar.h

@@ -0,0 +1,259 @@
+// 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 "format.h"
+
+#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
+#  include <locale>
+#endif
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template <typename T>
+using is_exotic_char = bool_constant<!std::is_same<T, char>::value>;
+
+inline auto write_loc(std::back_insert_iterator<detail::buffer<wchar_t>> out,
+                      loc_value value, const format_specs<wchar_t>& specs,
+                      locale_ref loc) -> bool {
+#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
+  auto& numpunct =
+      std::use_facet<std::numpunct<wchar_t>>(loc.get<std::locale>());
+  auto separator = std::wstring();
+  auto grouping = numpunct.grouping();
+  if (!grouping.empty()) separator = std::wstring(1, numpunct.thousands_sep());
+  return value.visit(loc_writer<wchar_t>{out, specs, separator, grouping, {}});
+#endif
+  return false;
+}
+}  // namespace detail
+
+FMT_BEGIN_EXPORT
+
+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;
+inline auto runtime(wstring_view s) -> wstring_view { return s; }
+#else
+template <typename... Args>
+using wformat_string = basic_format_string<wchar_t, type_identity_t<Args>...>;
+inline auto runtime(wstring_view s) -> runtime_format_string<wchar_t> {
+  return {{s}};
+}
+#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... T>
+constexpr auto make_wformat_args(const T&... args)
+    -> format_arg_store<wformat_context, T...> {
+  return {args...};
+}
+
+inline namespace literals {
+#if FMT_USE_USER_DEFINED_LITERALS && !FMT_USE_NONTYPE_TEMPLATE_ARGS
+constexpr auto operator""_a(const wchar_t* s, size_t)
+    -> detail::udl_arg<wchar_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> {
+  auto buf = basic_memory_buffer<Char>();
+  detail::vformat_to(buf, format_str, args);
+  return to_string(buf);
+}
+
+template <typename... T>
+auto format(wformat_string<T...> fmt, T&&... args) -> std::wstring {
+  return vformat(fmt::wstring_view(fmt), fmt::make_wformat_args(args...));
+}
+
+// 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... T, typename Char = char_t<S>,
+          FMT_ENABLE_IF(!std::is_same<Char, char>::value &&
+                        !std::is_same<Char, wchar_t>::value)>
+auto format(const S& format_str, T&&... args) -> std::basic_string<Char> {
+  return vformat(detail::to_string_view(format_str),
+                 fmt::make_format_args<buffer_context<Char>>(args...));
+}
+
+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, detail::to_string_view(format_str), args);
+}
+
+template <typename Locale, typename S, typename... T, 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, T&&... args)
+    -> std::basic_string<Char> {
+  return detail::vformat(loc, detail::to_string_view(format_str),
+                         fmt::make_format_args<buffer_context<Char>>(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, detail::to_string_view(format_str), args);
+  return detail::get_iterator(buf, out);
+}
+
+template <typename OutputIt, typename S, typename... T,
+          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, T&&... args) -> OutputIt {
+  return vformat_to(out, detail::to_string_view(fmt),
+                    fmt::make_format_args<buffer_context<Char>>(args...));
+}
+
+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, detail::to_string_view(format_str), args,
+             detail::locale_ref(loc));
+  return detail::get_iterator(buf, out);
+}
+
+template <typename OutputIt, typename Locale, typename S, typename... T,
+          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,
+                      T&&... args) ->
+    typename std::enable_if<enable, OutputIt>::type {
+  return vformat_to(out, loc, detail::to_string_view(format_str),
+                    fmt::make_format_args<buffer_context<Char>>(args...));
+}
+
+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> {
+  using traits = detail::fixed_buffer_traits;
+  auto buf = detail::iterator_buffer<OutputIt, Char, traits>(out, n);
+  detail::vformat_to(buf, format_str, args);
+  return {buf.out(), buf.count()};
+}
+
+template <typename OutputIt, typename S, typename... T,
+          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, T&&... args)
+    -> format_to_n_result<OutputIt> {
+  return vformat_to_n(out, n, detail::to_string_view(fmt),
+                      fmt::make_format_args<buffer_context<Char>>(args...));
+}
+
+template <typename S, typename... T, typename Char = char_t<S>,
+          FMT_ENABLE_IF(detail::is_exotic_char<Char>::value)>
+inline auto formatted_size(const S& fmt, T&&... args) -> size_t {
+  auto buf = detail::counting_buffer<Char>();
+  detail::vformat_to(buf, detail::to_string_view(fmt),
+                     fmt::make_format_args<buffer_context<Char>>(args...));
+  return buf.count();
+}
+
+inline void vprint(std::FILE* f, wstring_view fmt, wformat_args args) {
+  auto buf = wmemory_buffer();
+  detail::vformat_to(buf, fmt, args);
+  buf.push_back(L'\0');
+  if (std::fputws(buf.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...));
+}
+
+template <typename... T>
+void println(std::FILE* f, wformat_string<T...> fmt, T&&... args) {
+  return print(f, L"{}\n", fmt::format(fmt, std::forward<T>(args)...));
+}
+
+template <typename... T> void println(wformat_string<T...> fmt, T&&... args) {
+  return print(L"{}\n", fmt::format(fmt, std::forward<T>(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_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_XCHAR_H_

src/fmt.cc

@@ -0,0 +1,108 @@
+module;
+
+// Put all implementation-provided headers into the global module fragment
+// to prevent attachment to this module.
+#include <algorithm>
+#include <cerrno>
+#include <chrono>
+#include <climits>
+#include <cmath>
+#include <cstddef>
+#include <cstdint>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <ctime>
+#include <exception>
+#include <filesystem>
+#include <fstream>
+#include <functional>
+#include <iterator>
+#include <limits>
+#include <locale>
+#include <memory>
+#include <optional>
+#include <ostream>
+#include <stdexcept>
+#include <string>
+#include <string_view>
+#include <system_error>
+#include <thread>
+#include <type_traits>
+#include <typeinfo>
+#include <utility>
+#include <variant>
+#include <vector>
+#include <version>
+
+#if __has_include(<cxxabi.h>)
+#  include <cxxabi.h>
+#endif
+#if defined(_MSC_VER) || defined(__MINGW32__)
+#  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
+#  if defined(__GLIBCXX__)
+#    include <ext/stdio_filebuf.h>
+#    include <ext/stdio_sync_filebuf.h>
+#  endif
+#  define WIN32_LEAN_AND_MEAN
+#  include <windows.h>
+#endif
+
+export module fmt;
+
+#define FMT_EXPORT export
+#define FMT_BEGIN_EXPORT export {
+#define FMT_END_EXPORT }
+
+// If you define FMT_ATTACH_TO_GLOBAL_MODULE
+//  - all declarations are detached from module 'fmt'
+//  - the module behaves like a traditional static library, too
+//  - all library symbols are mangled traditionally
+//  - you can mix TUs with either importing or #including the {fmt} API
+#ifdef FMT_ATTACH_TO_GLOBAL_MODULE
+extern "C++" {
+#endif
+
+// 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/std.h"
+#include "fmt/xchar.h"
+
+#ifdef FMT_ATTACH_TO_GLOBAL_MODULE
+}
+#endif
+
+// gcc doesn't yet implement private module fragments
+#if !FMT_GCC_VERSION
+module :private;
+#endif
+
+#include "format.cc"
+#include "os.cc"

src/format.cc

@@ -8,40 +8,36 @@
 #include "fmt/format-inl.h"
 
 FMT_BEGIN_NAMESPACE
+namespace detail {
 
-template struct internal::basic_data<void>;
+template FMT_API auto dragonbox::to_decimal(float x) noexcept
+    -> dragonbox::decimal_fp<float>;
+template FMT_API auto dragonbox::to_decimal(double x) noexcept
+    -> dragonbox::decimal_fp<double>;
+
+#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
+template FMT_API locale_ref::locale_ref(const std::locale& loc);
+template FMT_API auto locale_ref::get<std::locale>() const -> std::locale;
+#endif
 
 // Explicit instantiations for char.
 
-template FMT_API char internal::thousands_sep(locale_provider *lp);
+template FMT_API auto thousands_sep_impl(locale_ref)
+    -> thousands_sep_result<char>;
+template FMT_API auto decimal_point_impl(locale_ref) -> char;
 
-template void basic_fixed_buffer<char>::grow(std::size_t);
+template FMT_API void buffer<char>::append(const char*, const char*);
 
-template void internal::arg_map<format_context>::init(
-    const basic_format_args<format_context> &args);
-
-template FMT_API int internal::char_traits<char>::format_float(
-    char *buffer, std::size_t size, const char *format,
-    unsigned width, int precision, double value);
-
-template FMT_API int internal::char_traits<char>::format_float(
-    char *buffer, std::size_t size, const char *format,
-    unsigned width, int precision, long double value);
+template FMT_API void vformat_to(buffer<char>&, string_view,
+                                 typename vformat_args<>::type, locale_ref);
 
 // Explicit instantiations for wchar_t.
 
-template FMT_API wchar_t internal::thousands_sep(locale_provider *lp);
+template FMT_API auto thousands_sep_impl(locale_ref)
+    -> thousands_sep_result<wchar_t>;
+template FMT_API auto decimal_point_impl(locale_ref) -> wchar_t;
 
-template void basic_fixed_buffer<wchar_t>::grow(std::size_t);
+template FMT_API void buffer<wchar_t>::append(const wchar_t*, const wchar_t*);
 
-template void internal::arg_map<wformat_context>::init(
-    const basic_format_args<wformat_context> &args);
-
-template FMT_API int internal::char_traits<wchar_t>::format_float(
-    wchar_t *buffer, std::size_t size, const wchar_t *format,
-    unsigned width, int precision, double value);
-
-template FMT_API int internal::char_traits<wchar_t>::format_float(
-    wchar_t *buffer, std::size_t size, const wchar_t *format,
-    unsigned width, int precision, long double value);
+}  // namespace detail
 FMT_END_NAMESPACE

src/os.cc

@@ -0,0 +1,402 @@
+// Formatting library for C++ - optional OS-specific functionality
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+// Disable bogus MSVC warnings.
+#if !defined(_CRT_SECURE_NO_WARNINGS) && defined(_MSC_VER)
+#  define _CRT_SECURE_NO_WARNINGS
+#endif
+
+#include "fmt/os.h"
+
+#include <climits>
+
+#if FMT_USE_FCNTL
+#  include <sys/stat.h>
+#  include <sys/types.h>
+
+#  ifdef _WRS_KERNEL    // VxWorks7 kernel
+#    include <ioLib.h>  // getpagesize
+#  endif
+
+#  ifndef _WIN32
+#    include <unistd.h>
+#  else
+#    ifndef WIN32_LEAN_AND_MEAN
+#      define WIN32_LEAN_AND_MEAN
+#    endif
+#    include <io.h>
+
+#    ifndef S_IRUSR
+#      define S_IRUSR _S_IREAD
+#    endif
+#    ifndef S_IWUSR
+#      define S_IWUSR _S_IWRITE
+#    endif
+#    ifndef S_IRGRP
+#      define S_IRGRP 0
+#    endif
+#    ifndef S_IWGRP
+#      define S_IWGRP 0
+#    endif
+#    ifndef S_IROTH
+#      define S_IROTH 0
+#    endif
+#    ifndef S_IWOTH
+#      define S_IWOTH 0
+#    endif
+#  endif  // _WIN32
+#endif    // FMT_USE_FCNTL
+
+#ifdef _WIN32
+#  include <windows.h>
+#endif
+
+namespace {
+#ifdef _WIN32
+// Return type of read and write functions.
+using rwresult = int;
+
+// On Windows the count argument to read and write is unsigned, so convert
+// it from size_t preventing integer overflow.
+inline unsigned convert_rwcount(std::size_t count) {
+  return count <= UINT_MAX ? static_cast<unsigned>(count) : UINT_MAX;
+}
+#elif FMT_USE_FCNTL
+// Return type of read and write functions.
+using rwresult = ssize_t;
+
+inline std::size_t convert_rwcount(std::size_t count) { return count; }
+#endif
+}  // namespace
+
+FMT_BEGIN_NAMESPACE
+
+#ifdef _WIN32
+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) 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 noexcept { return result_ != 0; }
+  operator basic_string_view<wchar_t>() const noexcept {
+    return basic_string_view<wchar_t>(message_, result_);
+  }
+};
+
+class utf8_system_category final : public std::error_category {
+ public:
+  const char* name() const noexcept override { return "system"; }
+  std::string message(int error_code) const override {
+    auto&& msg = system_message(error_code);
+    if (msg) {
+      auto utf8_message = to_utf8<wchar_t>();
+      if (utf8_message.convert(msg)) {
+        return utf8_message.str();
+      }
+    }
+    return "unknown error";
+  }
+};
+
+}  // namespace detail
+
+FMT_API const std::error_category& system_category() 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,
+                                  const char* message) noexcept {
+  FMT_TRY {
+    auto&& msg = system_message(error_code);
+    if (msg) {
+      auto utf8_message = to_utf8<wchar_t>();
+      if (utf8_message.convert(msg)) {
+        fmt::format_to(appender(out), FMT_STRING("{}: {}"), message,
+                       string_view(utf8_message));
+        return;
+      }
+    }
+  }
+  FMT_CATCH(...) {}
+  format_error_code(out, error_code, message);
+}
+
+void report_windows_error(int error_code, const char* message) noexcept {
+  report_error(detail::format_windows_error, error_code, message);
+}
+#endif  // _WIN32
+
+buffered_file::~buffered_file() noexcept {
+  if (file_ && FMT_SYSTEM(fclose(file_)) != 0)
+    report_system_error(errno, "cannot close file");
+}
+
+buffered_file::buffered_file(cstring_view filename, cstring_view mode) {
+  FMT_RETRY_VAL(file_, FMT_SYSTEM(fopen(filename.c_str(), mode.c_str())),
+                nullptr);
+  if (!file_)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot open file {}"),
+                           filename.c_str()));
+}
+
+void buffered_file::close() {
+  if (!file_) return;
+  int result = FMT_SYSTEM(fclose(file_));
+  file_ = nullptr;
+  if (result != 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot close file")));
+}
+
+int buffered_file::descriptor() const {
+#if !defined(fileno)
+  int fd = FMT_POSIX_CALL(fileno(file_));
+#elif defined(FMT_HAS_SYSTEM)
+  // fileno is a macro on OpenBSD so we cannot use FMT_POSIX_CALL.
+#  define FMT_DISABLE_MACRO
+  int fd = FMT_SYSTEM(fileno FMT_DISABLE_MACRO(file_));
+#else
+  int fd = fileno(file_);
+#endif
+  if (fd == -1)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot get file descriptor")));
+  return fd;
+}
+
+#if FMT_USE_FCNTL
+#  ifdef _WIN32
+using mode_t = int;
+#  endif
+constexpr mode_t default_open_mode =
+    S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
+
+file::file(cstring_view path, int oflag) {
+#  if defined(_WIN32) && !defined(__MINGW32__)
+  fd_ = -1;
+  auto converted = detail::utf8_to_utf16(string_view(path.c_str()));
+  *this = file::open_windows_file(converted.c_str(), oflag);
+#  else
+  FMT_RETRY(fd_, FMT_POSIX_CALL(open(path.c_str(), oflag, default_open_mode)));
+  if (fd_ == -1)
+    FMT_THROW(
+        system_error(errno, FMT_STRING("cannot open file {}"), path.c_str()));
+#  endif
+}
+
+file::~file() noexcept {
+  // Don't retry close in case of EINTR!
+  // See http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-09/3000.html
+  if (fd_ != -1 && FMT_POSIX_CALL(close(fd_)) != 0)
+    report_system_error(errno, "cannot close file");
+}
+
+void file::close() {
+  if (fd_ == -1) return;
+  // Don't retry close in case of EINTR!
+  // See http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-09/3000.html
+  int result = FMT_POSIX_CALL(close(fd_));
+  fd_ = -1;
+  if (result != 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot close file")));
+}
+
+long long file::size() const {
+#  ifdef _WIN32
+  // Use GetFileSize instead of GetFileSizeEx for the case when _WIN32_WINNT
+  // is less than 0x0500 as is the case with some default MinGW builds.
+  // Both functions support large file sizes.
+  DWORD size_upper = 0;
+  HANDLE handle = reinterpret_cast<HANDLE>(_get_osfhandle(fd_));
+  DWORD size_lower = FMT_SYSTEM(GetFileSize(handle, &size_upper));
+  if (size_lower == INVALID_FILE_SIZE) {
+    DWORD error = GetLastError();
+    if (error != NO_ERROR)
+      FMT_THROW(windows_error(GetLastError(), "cannot get file size"));
+  }
+  unsigned long long long_size = size_upper;
+  return (long_size << sizeof(DWORD) * CHAR_BIT) | size_lower;
+#  else
+  using Stat = struct stat;
+  Stat file_stat = Stat();
+  if (FMT_POSIX_CALL(fstat(fd_, &file_stat)) == -1)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot get file attributes")));
+  static_assert(sizeof(long long) >= sizeof(file_stat.st_size),
+                "return type of file::size is not large enough");
+  return file_stat.st_size;
+#  endif
+}
+
+std::size_t file::read(void* buffer, std::size_t count) {
+  rwresult result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(read(fd_, buffer, convert_rwcount(count))));
+  if (result < 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot read from file")));
+  return detail::to_unsigned(result);
+}
+
+std::size_t file::write(const void* buffer, std::size_t count) {
+  rwresult result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(write(fd_, buffer, convert_rwcount(count))));
+  if (result < 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot write to file")));
+  return detail::to_unsigned(result);
+}
+
+file file::dup(int fd) {
+  // Don't retry as dup doesn't return EINTR.
+  // http://pubs.opengroup.org/onlinepubs/009695399/functions/dup.html
+  int new_fd = FMT_POSIX_CALL(dup(fd));
+  if (new_fd == -1)
+    FMT_THROW(system_error(
+        errno, FMT_STRING("cannot duplicate file descriptor {}"), fd));
+  return file(new_fd);
+}
+
+void file::dup2(int fd) {
+  int result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(dup2(fd_, fd)));
+  if (result == -1) {
+    FMT_THROW(system_error(
+        errno, FMT_STRING("cannot duplicate file descriptor {} to {}"), fd_,
+        fd));
+  }
+}
+
+void file::dup2(int fd, std::error_code& ec) noexcept {
+  int result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(dup2(fd_, fd)));
+  if (result == -1) ec = std::error_code(errno, std::generic_category());
+}
+
+void file::pipe(file& read_end, file& write_end) {
+  // Close the descriptors first to make sure that assignments don't throw
+  // and there are no leaks.
+  read_end.close();
+  write_end.close();
+  int fds[2] = {};
+#  ifdef _WIN32
+  // Make the default pipe capacity same as on Linux 2.6.11+.
+  enum { DEFAULT_CAPACITY = 65536 };
+  int result = FMT_POSIX_CALL(pipe(fds, DEFAULT_CAPACITY, _O_BINARY));
+#  else
+  // Don't retry as the pipe function doesn't return EINTR.
+  // http://pubs.opengroup.org/onlinepubs/009696799/functions/pipe.html
+  int result = FMT_POSIX_CALL(pipe(fds));
+#  endif
+  if (result != 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot create pipe")));
+  // The following assignments don't throw because read_fd and write_fd
+  // are closed.
+  read_end = file(fds[0]);
+  write_end = file(fds[1]);
+}
+
+buffered_file file::fdopen(const char* mode) {
+// Don't retry as fdopen doesn't return EINTR.
+#  if defined(__MINGW32__) && defined(_POSIX_)
+  FILE* f = ::fdopen(fd_, mode);
+#  else
+  FILE* f = FMT_POSIX_CALL(fdopen(fd_, mode));
+#  endif
+  if (!f) {
+    FMT_THROW(system_error(
+        errno, FMT_STRING("cannot associate stream with file descriptor")));
+  }
+  buffered_file bf(f);
+  fd_ = -1;
+  return bf;
+}
+
+#  if defined(_WIN32) && !defined(__MINGW32__)
+file file::open_windows_file(wcstring_view path, int oflag) {
+  int fd = -1;
+  auto err = _wsopen_s(&fd, path.c_str(), oflag, _SH_DENYNO, default_open_mode);
+  if (fd == -1) {
+    FMT_THROW(system_error(err, FMT_STRING("cannot open file {}"),
+                           detail::to_utf8<wchar_t>(path.c_str()).c_str()));
+  }
+  return file(fd);
+}
+#  endif
+
+#  if !defined(__MSDOS__)
+long getpagesize() {
+#    ifdef _WIN32
+  SYSTEM_INFO si;
+  GetSystemInfo(&si);
+  return si.dwPageSize;
+#    else
+#      ifdef _WRS_KERNEL
+  long size = FMT_POSIX_CALL(getpagesize());
+#      else
+  long size = FMT_POSIX_CALL(sysconf(_SC_PAGESIZE));
+#      endif
+
+  if (size < 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot get memory page size")));
+  return size;
+#    endif
+}
+#  endif
+
+namespace detail {
+
+void file_buffer::grow(size_t) {
+  if (this->size() == this->capacity()) flush();
+}
+
+file_buffer::file_buffer(cstring_view path,
+                         const detail::ostream_params& params)
+    : file_(path, params.oflag) {
+  set(new char[params.buffer_size], params.buffer_size);
+}
+
+file_buffer::file_buffer(file_buffer&& other)
+    : detail::buffer<char>(other.data(), other.size(), other.capacity()),
+      file_(std::move(other.file_)) {
+  other.clear();
+  other.set(nullptr, 0);
+}
+
+file_buffer::~file_buffer() {
+  flush();
+  delete[] data();
+}
+}  // namespace detail
+
+ostream::~ostream() = default;
+#endif  // FMT_USE_FCNTL
+FMT_END_NAMESPACE

src/posix.cc

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

support/Android.mk

@@ -4,7 +4,7 @@ include $(CLEAR_VARS)
 LOCAL_MODULE := fmt_static
 LOCAL_MODULE_FILENAME := libfmt
 
-LOCAL_SRC_FILES := fmt/format.cc
+LOCAL_SRC_FILES := ../src/format.cc
 
 LOCAL_C_INCLUDES := $(LOCAL_PATH)
 LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)

support/AndroidManifest.xml

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

support/README

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

support/Vagrantfile

@@ -0,0 +1,20 @@
+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+# A vagrant config for testing against gcc-4.8.
+Vagrant.configure("2") do |config|
+  config.vm.box = "ubuntu/xenial64"
+  config.disksize.size = '15GB'
+
+  config.vm.provider "virtualbox" do |vb|
+    vb.memory = "4096"
+  end
+
+  config.vm.provision "shell", inline: <<-SHELL
+    apt-get update
+    apt-get install -y g++ make wget git
+    wget -q https://github.com/Kitware/CMake/releases/download/v3.26.0/cmake-3.26.0-Linux-x86_64.tar.gz
+    tar xzf cmake-3.26.0-Linux-x86_64.tar.gz
+    ln -s `pwd`/cmake-3.26.0-Linux-x86_64/bin/cmake /usr/local/bin
+  SHELL
+end

support/appveyor-build.py

@@ -1,33 +0,0 @@
-#!/usr/bin/env python
-# Build the project on AppVeyor.
-
-import os
-from subprocess import check_call
-
-build = os.environ['BUILD']
-config = os.environ['CONFIGURATION']
-platform = os.environ.get('PLATFORM')
-path = os.environ['PATH']
-cmake_command = ['cmake', '-DFMT_PEDANTIC=ON', '-DCMAKE_BUILD_TYPE=' + config]
-if build == 'mingw':
-    cmake_command.append('-GMinGW Makefiles')
-    build_command = ['mingw32-make', '-j4']
-    test_command = ['mingw32-make', 'test']
-    # Remove the path to Git bin directory from $PATH because it breaks
-    # MinGW config.
-    path = path.replace(r'C:\Program Files (x86)\Git\bin', '')
-    os.environ['PATH'] = r'C:\MinGW\bin;' + path
-else:
-    # Add MSBuild 14.0 to PATH as described in
-    # http://help.appveyor.com/discussions/problems/2229-v140-not-found-on-vs2105rc.
-    os.environ['PATH'] = r'C:\Program Files (x86)\MSBuild\15.0\Bin;' + path
-    generator = 'Visual Studio 15 2017'
-    if platform == 'x64':
-        generator += ' Win64'
-    cmake_command.append('-G' + generator)
-    build_command = ['cmake', '--build', '.', '--config', config, '--', '/m:4']
-    test_command = ['ctest', '-C', config]
-
-check_call(cmake_command)
-check_call(build_command)
-check_call(test_command)

support/appveyor.yml

@@ -1,27 +0,0 @@
-configuration:
-  - Debug
-  - Release
-
-image: Visual Studio 2017
-
-environment:
-  CTEST_OUTPUT_ON_FAILURE: 1
-  matrix:
-  - BUILD: msvc
-  - BUILD: msvc
-    PLATFORM: x64
-
-before_build:
-  # Workaround for CMake not wanting sh.exe on PATH for MinGW.
-  - set PATH=%PATH:C:\Program Files\Git\usr\bin;=%
-
-build_script:
-  - python support/appveyor-build.py
-
-on_failure:
-  - appveyor PushArtifact Testing/Temporary/LastTest.log
-  - appveyor AddTest test
-
-# Uncomment this to debug AppVeyor failures.
-#on_finish:
-#  - ps: $blockRdp = $true; iex ((new-object net.webclient).DownloadString('https://raw.githubusercontent.com/appveyor/ci/master/scripts/enable-rdp.ps1'))

support/bazel/.bazelversion

@@ -0,0 +1 @@
+6.1.2

support/bazel/BUILD.bazel

@@ -0,0 +1,28 @@
+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/os.h",
+        "include/fmt/ostream.h",
+        "include/fmt/printf.h",
+        "include/fmt/ranges.h",
+        "include/fmt/std.h",
+        "include/fmt/xchar.h",
+    ],
+    includes = [
+        "include",
+    ],
+    strip_include_prefix = "include",
+    visibility = ["//visibility:public"],
+)

support/bazel/README.md

@@ -0,0 +1,74 @@
+# Bazel support
+
+To get [Bazel](https://bazel.build/) working with {fmt} you can copy the files `BUILD.bazel`, `WORKSPACE.bazel`, 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/.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/.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`, 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`.
+
+# Using Bzlmod
+
+The [Bazel Central Registry](https://github.com/bazelbuild/bazel-central-registry/tree/main/modules/fmt) also provides support for {fmt}.

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

@@ -1,18 +1,32 @@
+import java.nio.file.Paths
+
 // General gradle arguments for root project
 buildscript {    
     repositories {
         google()
         jcenter()
     }
-
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.0.1'
+        //
+        // https://developer.android.com/studio/releases/gradle-plugin#updating-gradle
+        //
+        // Notice that 4.0.0 here is the version of [Android Gradle Plugin]
+        // According to URL above you will need Gradle 6.1 or higher
+        //
+        classpath "com.android.tools.build:gradle:4.1.1"
     }
 }
+repositories {
+    google()
+    jcenter()
+}
+
+// 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'
-
+apply plugin: "com.android.library"
 android {
     compileSdkVersion 25    // Android 7.0
 
@@ -24,21 +38,18 @@ android {
     splits {
         abi {
             enable true
-            // Be general, as much as possible ...
-            // universalApk true 
-
             // Specify platforms for Application
             reset()
-            include "x86", "x86_64", "armeabi-v7a", "arm64-v8a"
+            include  "arm64-v8a", "armeabi-v7a", "x86_64"
         }
     }
+    ndkVersion "21.3.6528147" // ANDROID_NDK_HOME is deprecated. Be explicit
 
     defaultConfig {
         minSdkVersion 21    // Android 5.0+
         targetSdkVersion 25 // Follow Compile SDK
-        versionCode 16      // Follow release count
-        versionName "4.1.0" // Follow Official version
-        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+        versionCode 34      // Follow release count
+        versionName "7.1.2" // Follow Official version
         
         externalNativeBuild {
             cmake {
@@ -46,10 +57,10 @@ android {
                 arguments "-DBUILD_SHARED_LIBS=true"    // Build shared object
                 arguments "-DFMT_TEST=false"            // Skip test
                 arguments "-DFMT_DOC=false"             // Skip document
-                cppFlags  "-std=c++14"
+                cppFlags  "-std=c++17"
+                targets   "fmt"
             }
         }
-        println("Gradle CMake Plugin: ")
         println(externalNativeBuild.cmake.cppFlags)
         println(externalNativeBuild.cmake.arguments)
     }
@@ -60,16 +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 "${rootDir}/include"
         }
     }
 }
@@ -79,20 +101,32 @@ assemble.doLast
     // Instead of `ninja install`, Gradle will deploy the files.
     // We are doing this since FMT is dependent to the ANDROID_STL after build
     copy {
-        from 'build/intermediates/cmake'
-        into '../libs'
+        from "build/intermediates/cmake"
+        into "${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/cmake/JoinPaths.cmake

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

support/cmake/cxx14.cmake

@@ -1,97 +0,0 @@
-# C++14 feature support detection
-
-if (NOT FMT_USE_CPP14)
-  return()
-endif ()
-
-include(CheckCXXCompilerFlag)
-
-if (FMT_USE_CPP14)
-  check_cxx_compiler_flag(-std=c++14 HAVE_STD_CPP14_FLAG)
-  if (HAVE_STD_CPP14_FLAG)
-    # Check if including cmath works with -std=c++14 and -O3.
-    # It may not in MinGW due to bug http://ehc.ac/p/mingw/bugs/2250/.
-    set(CMAKE_REQUIRED_FLAGS "-std=c++14 -O3")
-    check_cxx_source_compiles("
-      #include <cmath>
-      int main() {}" FMT_CPP14_CMATH)
-    # Check if including <unistd.h> works with -std=c++14.
-    # It may not in MinGW due to bug http://sourceforge.net/p/mingw/bugs/2024/.
-    check_cxx_source_compiles("
-      #include <unistd.h>
-      int main() {}" FMT_CPP14_UNISTD_H)
-    # Check if snprintf works with -std=c++14. It may not in MinGW.
-    check_cxx_source_compiles("
-      #include <stdio.h>
-      int main() {
-        char buffer[10];
-        snprintf(buffer, 10, \"foo\");
-      }" FMT_CPP14_SNPRINTF)
-    if (FMT_CPP14_CMATH AND FMT_CPP14_UNISTD_H AND FMT_CPP14_SNPRINTF)
-      set(CPP14_FLAG -std=c++14)
-    else ()
-      check_cxx_compiler_flag(-std=gnu++14 HAVE_STD_GNUPP14_FLAG)
-      if (HAVE_STD_CPP14_FLAG)
-        set(CPP14_FLAG -std=gnu++14)
-      endif ()
-    endif ()
-    set(CMAKE_REQUIRED_FLAGS )
-  else ()
-    check_cxx_compiler_flag(-std=c++1y HAVE_STD_CPP1Y_FLAG)
-    if (HAVE_STD_CPP1Y_FLAG)
-      set(CPP14_FLAG -std=c++1y)
-    else ()
-      # Fallback on c++11 if c++14 is not available.
-      check_cxx_compiler_flag(-std=c++11 HAVE_STD_CPP11_FLAG)
-      if (HAVE_STD_CPP11_FLAG)
-        set(CPP14_FLAG -std=c++11)
-      else ()
-        check_cxx_compiler_flag(-std=c++0x HAVE_STD_CPP0X_FLAG)
-        if (HAVE_STD_CPP0X_FLAG)
-          set(CPP14_FLAG -std=c++0x)
-        endif ()
-      endif ()
-    endif ()
-  endif ()
-endif ()
-
-if (CMAKE_CXX_STANDARD)
-  # Don't use -std compiler flag if CMAKE_CXX_STANDARD is specified.
-  set(CPP14_FLAG )
-endif ()
-
-message(STATUS "CPP14_FLAG: ${CPP14_FLAG}")
-set(CMAKE_REQUIRED_FLAGS ${CPP14_FLAG})
-
-# Check if variadic templates are working and not affected by GCC bug 39653:
-# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=39653
-check_cxx_source_compiles("
-  template <class T, class ...Types>
-  struct S { typedef typename S<Types...>::type type; };
-  int main() {}" SUPPORTS_VARIADIC_TEMPLATES)
-
-# Check if initializer lists are supported.
-check_cxx_source_compiles("
-  #include <initializer_list>
-  int main() {}" SUPPORTS_INITIALIZER_LIST)
-
-# Check if enum bases are available
-check_cxx_source_compiles("
-  enum C : char {A};
-  int main() {}"
-  SUPPORTS_ENUM_BASE)
-
-# Check if type traits are available
-check_cxx_source_compiles("
-  #include <type_traits>
-  class C { void operator=(const C&); };
-  int main() { static_assert(!std::is_copy_assignable<C>::value, \"\"); }"
-  SUPPORTS_TYPE_TRAITS)
-
-# Check if user-defined literals are available
-check_cxx_source_compiles("
-  void operator\"\" _udl(long double);
-  int main() {}"
-  SUPPORTS_USER_DEFINED_LITERALS)
-
-set(CMAKE_REQUIRED_FLAGS )

support/cmake/fmt-config.cmake.in

@@ -1,4 +1,7 @@
 @PACKAGE_INIT@
 
-include(${CMAKE_CURRENT_LIST_DIR}/@targets_export_name@.cmake)
+if (NOT TARGET fmt::fmt)
+  include(${CMAKE_CURRENT_LIST_DIR}/@targets_export_name@.cmake)
+endif ()
+
 check_required_components(fmt)

support/cmake/fmt.pc.in

@@ -0,0 +1,11 @@
+prefix=@CMAKE_INSTALL_PREFIX@
+exec_prefix=@CMAKE_INSTALL_PREFIX@
+libdir=@libdir_for_pc_file@
+includedir=@includedir_for_pc_file@
+
+Name: fmt
+Description: A modern formatting library
+Version: @FMT_VERSION@
+Libs: -L${libdir} -l@FMT_LIB_NAME@
+Cflags: -I${includedir}
+

support/cmake/run-cmake.bat

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

support/compute-powers.py

@@ -41,10 +41,13 @@ print('Significands:', end='')
 for i, fp in enumerate(powers):
     if i % 3 == 0:
         print(end='\n ')
-    print(' {:0<#16x}ull'.format(fp.f, ), end=',')
+    print(' {:0<#16x}'.format(fp.f, ), end=',')
 
 print('\n\nExponents:', end='')
 for i, fp in enumerate(powers):
     if i % 11 == 0:
         print(end='\n ')
     print(' {:5}'.format(fp.e), end=',')
+
+print('\n\nMax exponent difference:',
+      max([x.e - powers[i - 1].e for i, x in enumerate(powers)][1:]))

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

@@ -1,15 +1,18 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 """Manage site and releases.
 
 Usage:
   manage.py release [<branch>]
   manage.py site
+
+For the release command $FMT_TOKEN should contain a GitHub personal access token
+obtained from https://github.com/settings/tokens.
 """
 
 from __future__ import print_function
 import datetime, docopt, errno, fileinput, json, os
-import re, requests, shutil, sys, tempfile
+import re, requests, shutil, sys
 from contextlib import contextmanager
 from distutils.version import LooseVersion
 from subprocess import check_call
@@ -134,25 +137,66 @@ def update_site(env):
         if not os.path.exists(contents):
             os.rename(os.path.join(target_doc_dir, 'index.rst'), contents)
         # Fix issues in reference.rst/api.rst.
-        for filename in ['reference.rst', 'api.rst']:
+        for filename in ['reference.rst', 'api.rst', 'index.rst']:
             pattern = re.compile('doxygenfunction.. (bin|oct|hexu|hex)$', re.M)
             with rewrite(os.path.join(target_doc_dir, filename)) as b:
                 b.data = b.data.replace('std::ostream &', 'std::ostream&')
                 b.data = re.sub(pattern, r'doxygenfunction:: \1(int)', b.data)
                 b.data = b.data.replace('std::FILE*', 'std::FILE *')
                 b.data = b.data.replace('unsigned int', 'unsigned')
-                b.data = b.data.replace('operator""_', 'operator"" _')
+                #b.data = b.data.replace('operator""_', 'operator"" _')
+                b.data = b.data.replace(
+                    'format_to_n(OutputIt, size_t, string_view, Args&&',
+                    'format_to_n(OutputIt, size_t, const S&, const Args&')
+                b.data = b.data.replace(
+                    'format_to_n(OutputIt, std::size_t, string_view, Args&&',
+                    'format_to_n(OutputIt, std::size_t, const S&, const Args&')
+                if version == ('3.0.2'):
+                    b.data = b.data.replace(
+                        'fprintf(std::ostream&', 'fprintf(std::ostream &')
+                if version == ('5.3.0'):
+                    b.data = b.data.replace(
+                        'format_to(OutputIt, const S&, const Args&...)',
+                        'format_to(OutputIt, const S &, const Args &...)')
+                if version.startswith('5.') or version.startswith('6.'):
+                    b.data = b.data.replace(', size_t', ', std::size_t')
+                if version.startswith('7.'):
+                    b.data = b.data.replace(', std::size_t', ', size_t')
+                    b.data = b.data.replace('join(It, It', 'join(It, Sentinel')
+                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.'):
+                    b.data = b.data.replace(
+                        'vformat(const S&, basic_format_args<' +
+                        'buffer_context<Char>>)',
+                        'vformat(const S&, basic_format_args<' +
+                        'buffer_context<type_identity_t<Char>>>)')
         # Fix a broken link in index.rst.
         index = os.path.join(target_doc_dir, 'index.rst')
         with rewrite(index) as b:
             b.data = b.data.replace(
                 'doc/latest/index.html#format-string-syntax', 'syntax.html')
+        # Fix issues in syntax.rst.
+        index = os.path.join(target_doc_dir, 'syntax.rst')
+        with rewrite(index) as b:
+            b.data = b.data.replace(
+                '..productionlist:: sf\n', '.. productionlist:: sf\n ')
+            b.data = b.data.replace('Examples:\n', 'Examples::\n')
         # Build the docs.
         html_dir = os.path.join(env.build_dir, 'html')
         if os.path.exists(html_dir):
             shutil.rmtree(html_dir)
         include_dir = env.fmt_repo.dir
-        if LooseVersion(version) >= LooseVersion('3.0.0'):
+        if LooseVersion(version) >= LooseVersion('5.0.0'):
+            include_dir = os.path.join(include_dir, 'include', 'fmt')
+        elif LooseVersion(version) >= LooseVersion('3.0.0'):
             include_dir = os.path.join(include_dir, 'fmt')
         import build
         build.build_docs(version, doc_dir=target_doc_dir,
@@ -185,12 +229,50 @@ def release(args):
     if not fmt_repo.update('-b', branch, fmt_repo_url):
         clean_checkout(fmt_repo, branch)
 
-    # Convert changelog from RST to GitHub-flavored Markdown and get the
-    # version.
-    changelog = 'ChangeLog.rst'
+    # Update the date in the changelog and extract the version and the first
+    # section content.
+    changelog = 'ChangeLog.md'
     changelog_path = os.path.join(fmt_repo.dir, changelog)
-    import rst2md
-    changes, version = rst2md.convert(changelog_path)
+    is_first_section = True
+    first_section = []
+    for i, line in enumerate(fileinput.input(changelog_path, inplace=True)):
+        if i == 0:
+            version = re.match(r'# (.*) - TBD', line).group(1)
+            line = '# {} - {}\n'.format(
+                version, datetime.date.today().isoformat())
+        elif not is_first_section:
+            pass
+        elif line.startswith('#'):
+            is_first_section = False
+        else:
+            first_section.append(line)
+        sys.stdout.write(line)
+    if first_section[0] == '\n':
+        first_section.pop(0)
+
+    changes = ''
+    code_block = False
+    stripped = False
+    for line in first_section:
+        if re.match(r'^\s*```', line):
+            code_block = not code_block
+            changes += line
+            stripped = False
+            continue
+        if code_block:
+            changes += line
+            continue
+        if line == '\n':
+            changes += line
+            if stripped:
+                changes += line
+                stripped = False
+            continue
+        if stripped:
+            line = ' ' + line.lstrip()
+        changes += line.rstrip()
+        stripped = True
+
     cmakelists = 'CMakeLists.txt'
     for line in fileinput.input(os.path.join(fmt_repo.dir, cmakelists),
                                 inplace=True):
@@ -199,23 +281,11 @@ def release(args):
             line = prefix + version + ')\n'
         sys.stdout.write(line)
 
-    # 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'):
-            line = version + ' - ' + datetime.date.today().isoformat()
-            title_len = len(line)
-            line += '\n'
-        elif title_len:
-            line = '-' * title_len + '\n'
-            title_len = 0
-        sys.stdout.write(line)
-
     # Add the version to the build script.
     script = os.path.join('doc', 'build.py')
     script_path = os.path.join(fmt_repo.dir, script)
     for line in fileinput.input(script_path, inplace=True):
-      m = re.match(r'( *versions = )\[(.+)\]', line)
+      m = re.match(r'( *versions \+= )\[(.+)\]', line)
       if m:
         line = '{}[{}, \'{}\']\n'.format(m.group(1), m.group(2), version)
       sys.stdout.write(line)
@@ -232,9 +302,9 @@ def release(args):
 
     # Create a release on GitHub.
     fmt_repo.push('origin', 'release')
-    params = {'access_token': os.getenv('FMT_TOKEN')}
+    auth_headers = {'Authorization': 'token ' + os.getenv('FMT_TOKEN')}
     r = requests.post('https://api.github.com/repos/fmtlib/fmt/releases',
-                      params=params,
+                      headers=auth_headers,
                       data=json.dumps({'tag_name': version,
                                        'target_commitish': 'release',
                                        'body': changes, 'draft': True}))
@@ -243,12 +313,12 @@ def release(args):
     id = r.json()['id']
     uploads_url = 'https://uploads.github.com/repos/fmtlib/fmt/releases'
     package = 'fmt-{}.zip'.format(version)
-    with open('build/fmt/' + package, 'rb') as f:
-        r = requests.post(
-            '{}/{}/assets?name={}'.format(uploads_url, id, package),
-            params=params, files={package: f})
-        if r.status_code != 201:
-            raise Exception('Failed to upload an asset ' + str(r))
+    r = requests.post(
+        '{}/{}/assets?name={}'.format(uploads_url, id, package),
+        headers={'Content-Type': 'application/zip'} | auth_headers,
+        data=open('build/fmt/' + package, 'rb'))
+    if r.status_code != 201:
+        raise Exception('Failed to upload an asset ' + str(r))
 
 
 if __name__ == '__main__':

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("""\
+FMT_FUNC 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

@@ -1,127 +0,0 @@
-# reStructuredText (RST) to GitHub-flavored Markdown converter
-
-import re
-from docutils import core, nodes, writers
-
-
-def is_github_ref(node):
-    return re.match('https://github.com/.*/(issues|pull)/.*', node['refuri'])
-
-
-class Translator(nodes.NodeVisitor):
-    def __init__(self, document):
-        nodes.NodeVisitor.__init__(self, document)
-        self.output = ''
-        self.indent = 0
-        self.preserve_newlines = False
-
-    def write(self, text):
-        self.output += text.replace('\n', '\n' + ' ' * self.indent)
-
-    def visit_document(self, node):
-        pass
-
-    def depart_document(self, node):
-        pass
-
-    def visit_section(self, node):
-        pass
-
-    def depart_section(self, node):
-        # Skip all sections except the first one.
-        raise nodes.StopTraversal
-
-    def visit_title(self, node):
-        self.version = re.match(r'(\d+\.\d+\.\d+).*', node.children[0]).group(1)
-        raise nodes.SkipChildren
-
-    def depart_title(self, node):
-        pass
-
-    def visit_Text(self, node):
-        if not self.preserve_newlines:
-            node = node.replace('\n', ' ')
-        self.write(node)
-
-    def depart_Text(self, node):
-        pass
-
-    def visit_bullet_list(self, node):
-        pass
-
-    def depart_bullet_list(self, node):
-        pass
-
-    def visit_list_item(self, node):
-        self.write('* ')
-        self.indent += 2
-
-    def depart_list_item(self, node):
-        self.indent -= 2
-        self.write('\n\n')
-
-    def visit_paragraph(self, node):
-        pass
-
-    def depart_paragraph(self, node):
-        pass
-
-    def visit_reference(self, node):
-        if not is_github_ref(node):
-            self.write('[')
-
-    def depart_reference(self, node):
-        if not is_github_ref(node):
-            self.write('](' + node['refuri'] + ')')
-
-    def visit_target(self, node):
-        pass
-
-    def depart_target(self, node):
-        pass
-
-    def visit_literal(self, node):
-        self.write('`')
-
-    def depart_literal(self, node):
-        self.write('`')
-
-    def visit_literal_block(self, node):
-        self.write('\n\n```')
-        if 'c++' in node['classes']:
-            self.write('c++')
-        self.write('\n')
-        self.preserve_newlines = True
-
-    def depart_literal_block(self, node):
-        self.write('\n```\n')
-        self.preserve_newlines = False
-
-    def visit_inline(self, node):
-        pass
-
-    def depart_inline(self, node):
-        pass
-
-    def visit_image(self, node):
-        self.write('![](' + node['uri'] + ')')
-
-    def depart_image(self, node):
-        pass
-
-
-class MDWriter(writers.Writer):
-    """GitHub-flavored markdown writer"""
-
-    supported = ('md',)
-    """Formats this writer supports."""
-
-    def translate(self):
-        translator = Translator(self.document)
-        self.document.walkabout(translator)
-        self.output = (translator.output, translator.version)
-
-
-def convert(rst_path):
-    """Converts RST file to Markdown."""
-    return core.publish_file(source_path=rst_path, writer=MDWriter())

support/rtd/index.rst

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

support/rtd/theme/layout.html

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

support/travis-build.py

@@ -1,116 +0,0 @@
-#!/usr/bin/env python
-# Build the project on Travis CI.
-
-from __future__ import print_function
-import errno, os, re, shutil, subprocess, sys, tempfile, urllib
-from subprocess import call, check_call, check_output, 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 library.
-makedirs_if_not_exist(build_dir)
-common_cmake_flags = [
-    '-DCMAKE_INSTALL_PREFIX=' + install_dir, '-DCMAKE_BUILD_TYPE=' + build
-]
-extra_cmake_flags = []
-if standard != '14':
-    extra_cmake_flags = ['-DCMAKE_CXX_FLAGS=-std=c++' + standard]
-check_call(['cmake', '-DFMT_DOC=OFF', '-DFMT_PEDANTIC=ON', fmt_dir] +
-           common_cmake_flags + extra_cmake_flags, cwd=build_dir)
-
-# Build library.
-check_call(['make', '-j4'], cwd=build_dir)
-
-# Test library.
-env = os.environ.copy()
-env['CTEST_OUTPUT_ON_FAILURE'] = '1'
-if call(['make', 'test'], env=env, cwd=build_dir):
-    with open('Testing/Temporary/LastTest.log', 'r') as f:
-        print(f.read())
-    sys.exit(-1)
-
-# Install library.
-check_call(['make', 'install'], cwd=build_dir)
-
-# Test installation.
-makedirs_if_not_exist(test_build_dir)
-check_call(['cmake', '-DCMAKE_CXX_FLAGS=-std=c++' + standard,
-                     os.path.join(fmt_dir, "test", "find-package-test")] +
-           common_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

@@ -1,159 +1,201 @@
-#------------------------------------------------------------------------------
-# Build the google test library
+add_subdirectory(gtest)
 
-# 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_options(gmock PUBLIC ${CPP14_FLAG})
-target_compile_definitions(gmock PUBLIC GTEST_HAS_STD_WSTRING=1)
-target_include_directories(gmock PUBLIC .)
-
-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 ()
-
-if (NOT SUPPORTS_VARIADIC_TEMPLATES OR NOT SUPPORTS_INITIALIZER_LIST)
-  target_compile_definitions(gmock PUBLIC GTEST_LANG_CXX11=0)
-endif ()
-
-# Workaround a bug in implementation of variadic templates in MSVC11.
-if (MSVC)
-  target_compile_definitions(gmock PUBLIC _VARIADIC_MAX=10)
-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=0)
-
-#------------------------------------------------------------------------------
-# Build the actual library tests
+include(CheckSymbolExists)
 
 set(TEST_MAIN_SRC test-main.cc gtest-extra.cc gtest-extra.h util.cc)
 add_library(test-main STATIC ${TEST_MAIN_SRC})
-target_compile_definitions(test-main PUBLIC
-  FMT_USE_FILE_DESCRIPTORS=$<BOOL:${HAVE_OPEN}>)
-target_link_libraries(test-main gmock fmt)
-
-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 ()
+target_include_directories(test-main PUBLIC
+  $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
+target_link_libraries(test-main gtest fmt)
 
 function(add_fmt_executable name)
   add_executable(${name} ${ARGN})
-  if (MINGW)
-    target_link_libraries(${name} -static-libgcc -static-libstdc++)
+  # (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_compile_options(${name} PRIVATE -Wno-stringop-overflow)
+    # The linker flag is needed for LTO.
+    target_link_libraries(${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 ${PEDANTIC_COMPILE_FLAGS} -Wno-weak-vtables)
+    endif ()
+  elseif (ADD_FMT_TEST_MODULE)
+    set(libs test-main test-module)
+    set_source_files_properties(${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.
-  target_compile_definitions(${name} PRIVATE
-    FMT_USE_TYPE_TRAITS=$<BOOL:${SUPPORTS_TYPE_TRAITS}>
-    FMT_USE_ENUM_BASE=$<BOOL:${SUPPORTS_ENUM_BASE}>)
   if (FMT_PEDANTIC)
     target_compile_options(${name} PRIVATE ${PEDANTIC_COMPILE_FLAGS})
   endif ()
+  if (FMT_WERROR)
+    target_compile_options(${name} PRIVATE ${WERROR_FLAG})
+  endif ()
   add_test(NAME ${name} COMMAND ${name})
 endfunction()
 
-add_fmt_test(assert-test)
-add_fmt_test(gtest-extra-test)
-add_fmt_test(format-test)
-add_fmt_test(format-impl-test)
-add_fmt_test(ostream-test)
-add_fmt_test(printf-test)
-add_fmt_test(time-test)
-add_fmt_test(util-test mock-allocator.h)
-add_fmt_test(custom-formatter-test)
-add_fmt_test(ranges-test)
-
-# Enable stricter options for one test to make sure that the header is free of
-# warnings.
-if (FMT_PEDANTIC AND MSVC)
-  target_compile_options(format-test PRIVATE /W4)
+if (FMT_MODULE)
+  return ()
 endif ()
 
-if (HAVE_OPEN)
+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(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 HEADER_ONLY header-only-test.cc)
+endif ()
+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(ranges-test ranges-odr-test.cc)
+
+add_fmt_test(scan-test)
+check_symbol_exists(strptime "time.h" HAVE_STRPTIME)
+if (HAVE_STRPTIME)
+  target_compile_definitions(scan-test PRIVATE FMT_HAVE_STRPTIME)
+endif ()
+
+add_fmt_test(std-test)
+try_compile(compile_result_unused
+            ${CMAKE_CURRENT_BINARY_DIR}
+            SOURCES ${CMAKE_CURRENT_LIST_DIR}/detect-stdfs.cc
+            OUTPUT_VARIABLE RAWOUTPUT)
+string(REGEX REPLACE ".*libfound \"([^\"]*)\".*" "\\1" STDLIBFS "${RAWOUTPUT}")
+if (STDLIBFS)
+  target_link_libraries(std-test ${STDLIBFS})
+endif ()
+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 (FMT_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 cxx_std_11)
+  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_compile_definitions(posix-mock-test PRIVATE FMT_USE_FILE_DESCRIPTORS=1)
-  target_link_libraries(posix-mock-test gmock)
+  target_link_libraries(posix-mock-test gtest)
+  if (FMT_PEDANTIC)
+    target_compile_options(posix-mock-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
+  endif ()
   add_test(NAME posix-mock-test COMMAND posix-mock-test)
-  add_fmt_test(posix-test)
+  add_fmt_test(os-test)
 endif ()
 
-add_fmt_executable(header-only-test
-  header-only-test.cc header-only-test2.cc test-main.cc)
-target_link_libraries(header-only-test 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 ()
-
-# Test that the library can be compiled with exceptions disabled.
-check_cxx_compiler_flag(-fno-exceptions HAVE_FNO_EXCEPTIONS_FLAG)
-if (HAVE_FNO_EXCEPTIONS_FLAG)
-  add_library(noexception-test ../src/format.cc)
-  target_compile_options(noexception-test PUBLIC ${CPP14_FLAG})
-  target_include_directories(
-    noexception-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
-  target_compile_options(noexception-test PRIVATE -fno-exceptions)
-endif ()
+message(STATUS "FMT_PEDANTIC: ${FMT_PEDANTIC}")
 
 if (FMT_PEDANTIC)
-  # Test that the library compiles without windows.h.
-  if (CMAKE_SYSTEM_NAME STREQUAL "Windows")
-    add_library(no-windows-h-test ../src/format.cc)
-    target_compile_options(no-windows-h-test PUBLIC ${CPP14_FLAG})
+  # 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 noexception-test.cc)
     target_include_directories(
-      no-windows-h-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
-    target_compile_definitions(no-windows-h-test PRIVATE FMT_USE_WINDOWS_H=0)
+      noexception-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
+    target_compile_options(noexception-test PRIVATE -fno-exceptions)
+    target_compile_options(noexception-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
   endif ()
 
-  add_test(compile-test ${CMAKE_CTEST_COMMAND}
+  # Test that the library compiles without locale.
+  add_library(nolocale-test ../src/format.cc)
+  target_include_directories(
+    nolocale-test PRIVATE ${PROJECT_SOURCE_DIR}/include)
+  target_compile_definitions(
+    nolocale-test PRIVATE FMT_STATIC_THOUSANDS_SEPARATOR=1)
+endif ()
+
+# These tests are disabled on Windows because they take too long.
+# They are disabled on GCC < 4.9 because it can not parse UDLs without
+# a space after `operator""` but that is an incorrect syntax for any more
+# modern compiler.
+if (FMT_PEDANTIC AND NOT WIN32 AND NOT (
+    CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND
+    CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.9))
+  # Test if incorrect API usages produce compilation error.
+  add_test(compile-error-test ${CMAKE_CTEST_COMMAND}
     --build-and-test
-    "${CMAKE_CURRENT_SOURCE_DIR}/compile-test"
-    "${CMAKE_CURRENT_BINARY_DIR}/compile-test"
+    "${CMAKE_CURRENT_SOURCE_DIR}/compile-error-test"
+    "${CMAKE_CURRENT_BINARY_DIR}/compile-error-test"
     --build-generator ${CMAKE_GENERATOR}
     --build-makeprogram ${CMAKE_MAKE_PROGRAM}
-    --build-options 
+    --build-options
     "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
-    "-DCPP14_FLAG=${CPP14_FLAG}"
-    "-DSUPPORTS_USER_DEFINED_LITERALS=${SUPPORTS_USER_DEFINED_LITERALS}")
+    "-DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}"
+    "-DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}"
+    "-DCXX_STANDARD_FLAG=${CXX_STANDARD_FLAG}"
+    "-DFMT_DIR=${CMAKE_SOURCE_DIR}")
 
-  # test if the targets are findable from the build directory
+  # Test if the targets are found from the build directory.
   add_test(find-package-test ${CMAKE_CTEST_COMMAND}
     -C ${CMAKE_BUILD_TYPE}
     --build-and-test
@@ -163,11 +205,13 @@ if (FMT_PEDANTIC)
     --build-makeprogram ${CMAKE_MAKE_PROGRAM}
     --build-options
     "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
-    "-DCPP14_FLAG=${CPP14_FLAG}"
+    "-DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}"
+    "-DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}"
     "-DFMT_DIR=${PROJECT_BINARY_DIR}"
+    "-DPEDANTIC_COMPILE_FLAGS=${PEDANTIC_COMPILE_FLAGS}"
     "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}")
 
-  # test if the targets are findable when add_subdirectory is used
+  # Test if the targets are found when add_subdirectory is used.
   add_test(add-subdirectory-test ${CMAKE_CTEST_COMMAND}
     -C ${CMAKE_BUILD_TYPE}
     --build-and-test
@@ -177,6 +221,42 @@ if (FMT_PEDANTIC)
     --build-makeprogram ${CMAKE_MAKE_PROGRAM}
     --build-options
     "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
-    "-DCPP14_FLAG=${CPP14_FLAG}"
+    "-DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}"
+    "-DPEDANTIC_COMPILE_FLAGS=${PEDANTIC_COMPILE_FLAGS}"
     "-DCMAKE_BUILD_TYPE=${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)
+  if (${CMAKE_VERSION} VERSION_LESS 3.15)
+    find_package(CUDA 9.0)
+  else ()
+    include(CheckLanguage)
+    check_language(CUDA)
+    if (CMAKE_CUDA_COMPILER)
+      enable_language(CUDA OPTIONAL)
+      set(CUDA_FOUND TRUE)
+    endif ()
+  endif ()
+
+  if (CUDA_FOUND)
+    add_subdirectory(cuda-test)
+    add_test(NAME cuda-test COMMAND fmt-in-cuda-test)
+  endif ()
+endif ()

test/add-subdirectory-test/CMakeLists.txt

@@ -1,15 +1,17 @@
-cmake_minimum_required(VERSION 2.8.12)
+cmake_minimum_required(VERSION 3.8...3.25)
 
-project(fmt-test)
+project(fmt-test CXX)
 
 add_subdirectory(../.. fmt)
 
-add_executable(library-test "main.cc")
-target_compile_options(library-test PUBLIC ${CPP14_FLAG})
+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_compile_options(header-only-test PUBLIC ${CPP14_FLAG})
+  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 fmt::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.
@@ -8,15 +12,20 @@
 #include "fmt/core.h"
 #include "gtest/gtest.h"
 
+TEST(assert_test, fail) {
 #if GTEST_HAS_DEATH_TEST
-# define EXPECT_DEBUG_DEATH_IF_SUPPORTED(statement, regex) \
-    EXPECT_DEBUG_DEATH(statement, regex)
+  EXPECT_DEBUG_DEATH(FMT_ASSERT(false, "don't panic!"), "don't panic!");
 #else
-# define EXPECT_DEBUG_DEATH_IF_SUPPORTED(statement, regex) \
-    GTEST_UNSUPPORTED_DEATH_TEST_(statement, regex, )
+  fmt::print("warning: death tests are not supported\n");
 #endif
-
-TEST(AssertTest, Fail) {
-  EXPECT_DEBUG_DEATH_IF_SUPPORTED(
-      FMT_ASSERT(false, "don't panic!"), "don't panic!");
+}
+
+TEST(assert_test, dangling_else) {
+  bool test_condition = false;
+  bool executed_else = false;
+  if (test_condition)
+    FMT_ASSERT(true, "");
+  else
+    executed_else = true;
+  EXPECT_TRUE(executed_else);
 }

test/chrono-test.cc

@@ -0,0 +1,999 @@
+// Formatting library for C++ - time formatting tests
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include "fmt/chrono.h"
+
+#include <algorithm>
+#include <ctime>
+#include <vector>
+
+#include "gtest-extra.h"  // EXPECT_THROW_MSG
+#include "util.h"         // get_locale
+
+using fmt::runtime;
+using testing::Contains;
+
+template <typename Duration>
+using sys_time = std::chrono::time_point<std::chrono::system_clock, Duration>;
+
+#if defined(__MINGW32__) && !defined(_UCRT)
+// Only C89 conversion specifiers when using MSVCRT instead of UCRT
+#  define FMT_HAS_C99_STRFTIME 0
+#else
+#  define FMT_HAS_C99_STRFTIME 1
+#endif
+
+#if defined(__cpp_lib_chrono) && __cpp_lib_chrono >= 201907L
+using days = std::chrono::days;
+#else
+using days = std::chrono::duration<std::chrono::hours::rep, std::ratio<86400>>;
+#endif
+
+auto make_tm() -> std::tm {
+  auto time = std::tm();
+  time.tm_mday = 1;
+  return time;
+}
+
+auto make_hour(int h) -> std::tm {
+  auto time = make_tm();
+  time.tm_hour = h;
+  return time;
+}
+
+auto make_minute(int m) -> std::tm {
+  auto time = make_tm();
+  time.tm_min = m;
+  return time;
+}
+
+auto make_second(int s) -> std::tm {
+  auto time = make_tm();
+  time.tm_sec = s;
+  return time;
+}
+
+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, ' ', 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
+}
+
+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;
+  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
+  };
+
+#if !FMT_HAS_C99_STRFTIME
+  GTEST_SKIP() << "Skip the rest of this test because it relies on strftime() "
+                  "conforming to C99, but on this platform, MINGW + MSVCRT, "
+                  "the function conforms only to C89.";
+#endif
+
+  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));
+  }
+}
+
+// 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";
+  auto t = std::time(nullptr);
+  (void)fmt::format(fmt::runtime(s), *std::localtime(&t));
+}
+
+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(chrono_test, empty_result) { EXPECT_EQ(fmt::format("{}", std::tm()), ""); }
+
+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 &&
+         lhs.tm_wday == rhs.tm_wday && lhs.tm_yday == rhs.tm_yday &&
+         lhs.tm_isdst == rhs.tm_isdst;
+}
+
+TEST(chrono_test, gmtime) {
+  auto t = std::time(nullptr);
+  auto tm = *std::gmtime(&t);
+  EXPECT_TRUE(equal(tm, fmt::gmtime(t)));
+}
+
+template <typename TimePoint>
+auto strftime_full_utc(TimePoint tp) -> std::string {
+  auto t = std::chrono::system_clock::to_time_t(tp);
+  auto tm = *std::gmtime(&t);
+  return system_strftime("%Y-%m-%d %H:%M:%S", &tm);
+}
+
+TEST(chrono_test, system_clock_time_point) {
+  auto t1 = std::chrono::time_point_cast<std::chrono::seconds>(
+      std::chrono::system_clock::now());
+  EXPECT_EQ(strftime_full_utc(t1), fmt::format("{:%Y-%m-%d %H:%M:%S}", t1));
+  EXPECT_EQ(strftime_full_utc(t1), fmt::format("{}", t1));
+  EXPECT_EQ(strftime_full_utc(t1), fmt::format("{:}", t1));
+
+  auto t2 = sys_time<std::chrono::seconds>(std::chrono::seconds(42));
+  EXPECT_EQ(strftime_full_utc(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"};
+#ifndef _WIN32
+  // Disabled on Windows because these formats are not consistent among
+  // platforms.
+  spec_list.insert(spec_list.end(), {"%c", "%Ec", "%r"});
+#elif !FMT_HAS_C99_STRFTIME
+  // Only C89 conversion specifiers when using MSVCRT instead of UCRT
+  spec_list = {"%%", "%Y", "%y", "%b", "%B", "%m", "%U", "%W", "%j", "%d",
+               "%a", "%A", "%w", "%H", "%I", "%M", "%S", "%x", "%X", "%p"};
+#endif
+  spec_list.push_back("%Y-%m-%d %H:%M:%S");
+
+  for (const auto& spec : spec_list) {
+    auto t = std::chrono::system_clock::to_time_t(t1);
+    auto tm = *std::gmtime(&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));
+  }
+
+  // Timezone formatters tests makes sense for localtime.
+#if FMT_HAS_C99_STRFTIME
+  spec_list = {"%z", "%Z"};
+#else
+  spec_list = {"%Z"};
+#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), tm));
+
+    if (spec == "%z") {
+      sys_output.insert(sys_output.end() - 2, 1, ':');
+      EXPECT_EQ(sys_output, fmt::format("{:%Ez}", tm));
+      EXPECT_EQ(sys_output, fmt::format("{:%Oz}", tm));
+    }
+  }
+
+  // Separate tests for UTC, since std::time_put can use local time and ignoring
+  // the timezone in std::tm (if it presents on platform).
+  if (fmt::detail::has_member_data_tm_zone<std::tm>::value) {
+    auto t = std::chrono::system_clock::to_time_t(t1);
+    auto tm = *std::gmtime(&t);
+
+    std::vector<std::string> tz_names = {"GMT", "UTC"};
+    EXPECT_THAT(tz_names, Contains(fmt::format("{:%Z}", t1)));
+    EXPECT_THAT(tz_names, Contains(fmt::format("{:%Z}", tm)));
+  }
+
+  if (fmt::detail::has_member_data_tm_gmtoff<std::tm>::value) {
+    auto t = std::chrono::system_clock::to_time_t(t1);
+    auto tm = *std::gmtime(&t);
+
+    EXPECT_EQ(fmt::format("{:%z}", t1), "+0000");
+    EXPECT_EQ(fmt::format("{:%z}", tm), "+0000");
+
+    EXPECT_EQ(fmt::format("{:%Ez}", t1), "+00:00");
+    EXPECT_EQ(fmt::format("{:%Ez}", tm), "+00:00");
+
+    EXPECT_EQ(fmt::format("{:%Oz}", t1), "+00:00");
+    EXPECT_EQ(fmt::format("{:%Oz}", tm), "+00:00");
+  }
+}
+
+#if FMT_USE_LOCAL_TIME
+
+TEST(chrono_test, localtime) {
+  auto t = std::time(nullptr);
+  auto tm = *std::localtime(&t);
+  EXPECT_TRUE(equal(tm, fmt::localtime(t)));
+}
+
+template <typename Duration>
+auto strftime_full_local(std::chrono::local_time<Duration> tp) -> std::string {
+  auto t = std::chrono::system_clock::to_time_t(
+      std::chrono::current_zone()->to_sys(tp));
+  auto tm = *std::localtime(&t);
+  return system_strftime("%Y-%m-%d %H:%M:%S", &tm);
+}
+
+TEST(chrono_test, local_system_clock_time_point) {
+#  ifdef _WIN32
+  return;  // Not supported on Windows.
+#  endif
+  auto t1 = std::chrono::time_point_cast<std::chrono::seconds>(
+      std::chrono::current_zone()->to_local(std::chrono::system_clock::now()));
+  EXPECT_EQ(strftime_full_local(t1), fmt::format("{:%Y-%m-%d %H:%M:%S}", t1));
+  EXPECT_EQ(strftime_full_local(t1), fmt::format("{}", t1));
+  EXPECT_EQ(strftime_full_local(t1), fmt::format("{:}", t1));
+  using time_point = std::chrono::local_time<std::chrono::seconds>;
+  auto t2 = time_point(std::chrono::seconds(86400 + 42));
+  EXPECT_EQ(strftime_full_local(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"};
+#  ifndef _WIN32
+  // Disabled on Windows because these formats are not consistent among
+  // platforms.
+  spec_list.insert(spec_list.end(), {"%c", "%Ec", "%r"});
+#  elif !FMT_HAS_C99_STRFTIME
+  // Only C89 conversion specifiers when using MSVCRT instead of UCRT
+  spec_list = {"%%", "%Y", "%y", "%b", "%B", "%m", "%U", "%W", "%j", "%d", "%a",
+               "%A", "%w", "%H", "%I", "%M", "%S", "%x", "%X", "%p", "%Z"};
+#  endif
+  spec_list.push_back("%Y-%m-%d %H:%M:%S");
+
+  for (const auto& spec : spec_list) {
+    auto t = std::chrono::system_clock::to_time_t(
+        std::chrono::current_zone()->to_sys(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));
+  }
+
+  if (std::find(spec_list.cbegin(), spec_list.cend(), "%z") !=
+      spec_list.cend()) {
+    auto t = std::chrono::system_clock::to_time_t(
+        std::chrono::current_zone()->to_sys(t1));
+    auto tm = *std::localtime(&t);
+
+    auto sys_output = system_strftime("%z", &tm);
+    sys_output.insert(sys_output.end() - 2, 1, ':');
+
+    EXPECT_EQ(sys_output, fmt::format("{:%Ez}", t1));
+    EXPECT_EQ(sys_output, fmt::format("{:%Ez}", tm));
+
+    EXPECT_EQ(sys_output, fmt::format("{:%Oz}", t1));
+    EXPECT_EQ(sys_output, fmt::format("{:%Oz}", tm));
+  }
+}
+
+#endif  // FMT_USE_LOCAL_TIME
+
+#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
+
+TEST(chrono_test, format_default) {
+  EXPECT_EQ(fmt::format("{}", std::chrono::seconds(42)), "42s");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::atto>(42)),
+            "42as");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::femto>(42)),
+            "42fs");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::pico>(42)),
+            "42ps");
+  EXPECT_EQ(fmt::format("{}", std::chrono::nanoseconds(42)), "42ns");
+  EXPECT_EQ(fmt::format("{}", std::chrono::microseconds(42)), "42µs");
+  EXPECT_EQ(fmt::format("{}", std::chrono::milliseconds(42)), "42ms");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::centi>(42)),
+            "42cs");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::deci>(42)),
+            "42ds");
+  EXPECT_EQ(fmt::format("{}", std::chrono::seconds(42)), "42s");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::deca>(42)),
+            "42das");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::hecto>(42)),
+            "42hs");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::kilo>(42)),
+            "42ks");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::mega>(42)),
+            "42Ms");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::giga>(42)),
+            "42Gs");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::tera>(42)),
+            "42Ts");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::peta>(42)),
+            "42Ps");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<int, std::exa>(42)),
+            "42Es");
+  EXPECT_EQ(fmt::format("{}", std::chrono::minutes(42)), "42min");
+  EXPECT_EQ(fmt::format("{}", std::chrono::hours(42)), "42h");
+  EXPECT_EQ(fmt::format("{}", days(42)), "42d");
+  EXPECT_EQ(
+      fmt::format("{}", std::chrono::duration<int, std::ratio<15, 1>>(42)),
+      "42[15]s");
+  EXPECT_EQ(
+      fmt::format("{}", std::chrono::duration<int, std::ratio<15, 4>>(42)),
+      "42[15/4]s");
+}
+
+TEST(chrono_test, duration_align) {
+  auto s = std::chrono::seconds(42);
+  EXPECT_EQ(fmt::format("{:5}", s), "42s  ");
+  EXPECT_EQ(fmt::format("{:{}}", s, 5), "42s  ");
+  EXPECT_EQ(fmt::format("{:>5}", s), "  42s");
+  EXPECT_EQ(fmt::format("{:*^7}", s), "**42s**");
+  EXPECT_EQ(fmt::format("{:12%H:%M:%S}", std::chrono::seconds(12345)),
+            "03:25:45    ");
+  EXPECT_EQ(fmt::format("{:>12%H:%M:%S}", std::chrono::seconds(12345)),
+            "    03:25:45");
+  EXPECT_EQ(fmt::format("{:~^12%H:%M:%S}", std::chrono::seconds(12345)),
+            "~~03:25:45~~");
+  EXPECT_EQ(fmt::format("{:{}%H:%M:%S}", std::chrono::seconds(12345), 12),
+            "03:25:45    ");
+}
+
+TEST(chrono_test, tm_align) {
+  auto t = make_tm(1975, 12, 29, 12, 14, 16);
+  EXPECT_EQ(fmt::format("{:%F %T}", t), "1975-12-29 12:14:16");
+  EXPECT_EQ(fmt::format("{:30%F %T}", t), "1975-12-29 12:14:16           ");
+  EXPECT_EQ(fmt::format("{:{}%F %T}", t, 30), "1975-12-29 12:14:16           ");
+  EXPECT_EQ(fmt::format("{:<30%F %T}", t), "1975-12-29 12:14:16           ");
+  EXPECT_EQ(fmt::format("{:^30%F %T}", t), "     1975-12-29 12:14:16      ");
+  EXPECT_EQ(fmt::format("{:>30%F %T}", t), "           1975-12-29 12:14:16");
+
+  EXPECT_EQ(fmt::format("{:*<30%F %T}", t), "1975-12-29 12:14:16***********");
+  EXPECT_EQ(fmt::format("{:*^30%F %T}", t), "*****1975-12-29 12:14:16******");
+  EXPECT_EQ(fmt::format("{:*>30%F %T}", t), "***********1975-12-29 12:14:16");
+}
+
+TEST(chrono_test, tp_align) {
+  auto tp = std::chrono::time_point_cast<std::chrono::microseconds>(
+      std::chrono::system_clock::from_time_t(0));
+  EXPECT_EQ(fmt::format("{:%M:%S}", tp), "00:00.000000");
+  EXPECT_EQ(fmt::format("{:15%M:%S}", tp), "00:00.000000   ");
+  EXPECT_EQ(fmt::format("{:{}%M:%S}", tp, 15), "00:00.000000   ");
+  EXPECT_EQ(fmt::format("{:<15%M:%S}", tp), "00:00.000000   ");
+  EXPECT_EQ(fmt::format("{:^15%M:%S}", tp), " 00:00.000000  ");
+  EXPECT_EQ(fmt::format("{:>15%M:%S}", tp), "   00:00.000000");
+
+  EXPECT_EQ(fmt::format("{:*<15%M:%S}", tp), "00:00.000000***");
+  EXPECT_EQ(fmt::format("{:*^15%M:%S}", tp), "*00:00.000000**");
+  EXPECT_EQ(fmt::format("{:*>15%M:%S}", tp), "***00:00.000000");
+}
+
+TEST(chrono_test, format_specs) {
+  EXPECT_EQ(fmt::format("{:%%}", std::chrono::seconds(0)), "%");
+  EXPECT_EQ(fmt::format("{:%n}", std::chrono::seconds(0)), "\n");
+  EXPECT_EQ(fmt::format("{:%t}", std::chrono::seconds(0)), "\t");
+  EXPECT_EQ(fmt::format("{:%S}", std::chrono::seconds(0)), "00");
+  EXPECT_EQ(fmt::format("{:%S}", std::chrono::seconds(60)), "00");
+  EXPECT_EQ(fmt::format("{:%S}", std::chrono::seconds(42)), "42");
+  EXPECT_EQ(fmt::format("{:%S}", std::chrono::milliseconds(1234)), "01.234");
+  EXPECT_EQ(fmt::format("{:%M}", std::chrono::minutes(0)), "00");
+  EXPECT_EQ(fmt::format("{:%M}", std::chrono::minutes(60)), "00");
+  EXPECT_EQ(fmt::format("{:%M}", std::chrono::minutes(42)), "42");
+  EXPECT_EQ(fmt::format("{:%M}", std::chrono::seconds(61)), "01");
+  EXPECT_EQ(fmt::format("{:%H}", std::chrono::hours(0)), "00");
+  EXPECT_EQ(fmt::format("{:%H}", std::chrono::hours(24)), "00");
+  EXPECT_EQ(fmt::format("{:%H}", std::chrono::hours(14)), "14");
+  EXPECT_EQ(fmt::format("{:%H}", std::chrono::minutes(61)), "01");
+  EXPECT_EQ(fmt::format("{:%I}", std::chrono::hours(0)), "12");
+  EXPECT_EQ(fmt::format("{:%I}", std::chrono::hours(12)), "12");
+  EXPECT_EQ(fmt::format("{:%I}", std::chrono::hours(24)), "12");
+  EXPECT_EQ(fmt::format("{:%I}", std::chrono::hours(4)), "04");
+  EXPECT_EQ(fmt::format("{:%I}", std::chrono::hours(14)), "02");
+  EXPECT_EQ(fmt::format("{:%j}", days(12345)), "12345");
+  EXPECT_EQ(fmt::format("{:%j}", std::chrono::hours(12345 * 24 + 12)), "12345");
+  EXPECT_EQ(fmt::format("{:%H:%M:%S}", std::chrono::seconds(12345)),
+            "03:25:45");
+  EXPECT_EQ(fmt::format("{:%R}", std::chrono::seconds(12345)), "03:25");
+  EXPECT_EQ(fmt::format("{:%T}", std::chrono::seconds(12345)), "03:25:45");
+  EXPECT_EQ(fmt::format("{:%Q}", std::chrono::seconds(12345)), "12345");
+  EXPECT_EQ(fmt::format("{:%q}", std::chrono::seconds(12345)), "s");
+}
+
+TEST(chrono_test, invalid_specs) {
+  auto sec = std::chrono::seconds(0);
+  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((void)fmt::format(runtime("{:%Oq}"), sec), fmt::format_error,
+                   "invalid format");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:abc}"), sec), fmt::format_error,
+                   "invalid format");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:.2f}"), sec), fmt::format_error,
+                   "invalid format");
+}
+
+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));
+  EXPECT_TIME("%OS", make_second(42), std::chrono::seconds(42));
+  auto time = make_tm();
+  time.tm_hour = 3;
+  time.tm_min = 25;
+  time.tm_sec = 45;
+  auto sec = std::chrono::seconds(12345);
+  EXPECT_TIME("%r", time, sec);
+  EXPECT_TIME("%p", time, sec);
+}
+
+using dms = std::chrono::duration<double, std::milli>;
+
+TEST(chrono_test, format_default_fp) {
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<float>(1.234)), "1.234s");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<float, std::milli>(1.234)),
+            "1.234ms");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<double>(1.234)), "1.234s");
+  EXPECT_EQ(fmt::format("{}", dms(1.234)), "1.234ms");
+}
+
+TEST(chrono_test, format_precision) {
+  EXPECT_THROW_MSG(
+      (void)fmt::format(runtime("{:.2%Q}"), std::chrono::seconds(42)),
+      fmt::format_error, "precision not allowed for this argument type");
+  EXPECT_EQ(fmt::format("{:.0}", dms(1.234)), "1ms");
+  EXPECT_EQ(fmt::format("{:.1}", dms(1.234)), "1.2ms");
+  EXPECT_EQ(fmt::format("{:.{}}", dms(1.234), 2), "1.23ms");
+
+  EXPECT_EQ(fmt::format("{:.0}", dms(12.56)), "13ms");
+  EXPECT_EQ(fmt::format("{:.1}", dms(12.56)), "12.6ms");
+  EXPECT_EQ(fmt::format("{:.2}", dms(12.56)), "12.56ms");
+}
+
+TEST(chrono_test, format_full_specs) {
+  EXPECT_EQ(fmt::format("{:6.0}", dms(1.234)), "1ms   ");
+  EXPECT_EQ(fmt::format("{:6.1}", dms(1.234)), "1.2ms ");
+  EXPECT_EQ(fmt::format("{:>8.{}}", dms(1.234), 2), "  1.23ms");
+  EXPECT_EQ(fmt::format("{:^{}.{}}", dms(1.234), 7, 1), " 1.2ms ");
+  EXPECT_EQ(fmt::format("{0:^{2}.{1}}", dms(1.234), 2, 8), " 1.23ms ");
+  EXPECT_EQ(fmt::format("{:=^{}.{}}", dms(1.234), 9, 3), "=1.234ms=");
+  EXPECT_EQ(fmt::format("{:*^10.4}", dms(1.234)), "*1.2340ms*");
+
+  EXPECT_EQ(fmt::format("{:6.0}", dms(12.56)), "13ms  ");
+  EXPECT_EQ(fmt::format("{:>8.{}}", dms(12.56), 0), "    13ms");
+  EXPECT_EQ(fmt::format("{:^{}.{}}", dms(12.56), 6, 0), " 13ms ");
+  EXPECT_EQ(fmt::format("{0:^{2}.{1}}", dms(12.56), 0, 8), "  13ms  ");
+  EXPECT_EQ(fmt::format("{:=^{}.{}}", dms(12.56), 9, 0), "==13ms===");
+  EXPECT_EQ(fmt::format("{:*^10.0}", dms(12.56)), "***13ms***");
+}
+
+TEST(chrono_test, format_simple_q) {
+  EXPECT_EQ(fmt::format("{:%Q %q}", std::chrono::duration<float>(1.234)),
+            "1.234 s");
+  EXPECT_EQ(
+      fmt::format("{:%Q %q}", std::chrono::duration<float, std::milli>(1.234)),
+      "1.234 ms");
+  EXPECT_EQ(fmt::format("{:%Q %q}", std::chrono::duration<double>(1.234)),
+            "1.234 s");
+  EXPECT_EQ(fmt::format("{:%Q %q}", dms(1.234)), "1.234 ms");
+}
+
+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(fmt::format("{:.1%Q %q}", dms(1.234)), "1.2 ms");
+  EXPECT_EQ(fmt::format("{:.{}%Q %q}", dms(1.234), 2), "1.23 ms");
+}
+
+TEST(chrono_test, format_full_specs_q) {
+  EXPECT_EQ(fmt::format("{:7.0%Q %q}", dms(1.234)), "1 ms   ");
+  EXPECT_EQ(fmt::format("{:7.1%Q %q}", dms(1.234)), "1.2 ms ");
+  EXPECT_EQ(fmt::format("{:>8.{}%Q %q}", dms(1.234), 2), " 1.23 ms");
+  EXPECT_EQ(fmt::format("{:^{}.{}%Q %q}", dms(1.234), 8, 1), " 1.2 ms ");
+  EXPECT_EQ(fmt::format("{0:^{2}.{1}%Q %q}", dms(1.234), 2, 9), " 1.23 ms ");
+  EXPECT_EQ(fmt::format("{:=^{}.{}%Q %q}", dms(1.234), 10, 3), "=1.234 ms=");
+  EXPECT_EQ(fmt::format("{:*^11.4%Q %q}", dms(1.234)), "*1.2340 ms*");
+
+  EXPECT_EQ(fmt::format("{:7.0%Q %q}", dms(12.56)), "13 ms  ");
+  EXPECT_EQ(fmt::format("{:>8.{}%Q %q}", dms(12.56), 0), "   13 ms");
+  EXPECT_EQ(fmt::format("{:^{}.{}%Q %q}", dms(12.56), 8, 0), " 13 ms  ");
+  EXPECT_EQ(fmt::format("{0:^{2}.{1}%Q %q}", dms(12.56), 0, 9), "  13 ms  ");
+  EXPECT_EQ(fmt::format("{:=^{}.{}%Q %q}", dms(12.56), 9, 0), "==13 ms==");
+  EXPECT_EQ(fmt::format("{:*^11.0%Q %q}", dms(12.56)), "***13 ms***");
+}
+
+TEST(chrono_test, invalid_width_id) {
+  EXPECT_THROW((void)fmt::format(runtime("{:{o}"), std::chrono::seconds(0)),
+               fmt::format_error);
+}
+
+TEST(chrono_test, invalid_colons) {
+  EXPECT_THROW((void)fmt::format(runtime("{0}=:{0::"), std::chrono::seconds(0)),
+               fmt::format_error);
+}
+
+TEST(chrono_test, negative_durations) {
+  EXPECT_EQ(fmt::format("{:%Q}", std::chrono::seconds(-12345)), "-12345");
+  EXPECT_EQ(fmt::format("{:%H:%M:%S}", std::chrono::seconds(-12345)),
+            "-03:25:45");
+  EXPECT_EQ(fmt::format("{:%M:%S}", std::chrono::duration<double>(-1)),
+            "-00:01");
+  EXPECT_EQ(fmt::format("{:%q}", std::chrono::seconds(-12345)), "s");
+  EXPECT_EQ(fmt::format("{:%S}",
+                        std::chrono::duration<signed char, std::milli>(-127)),
+            "-00.127");
+  auto min = std::numeric_limits<int>::min();
+  EXPECT_EQ(fmt::format("{}", min),
+            fmt::format("{:%Q}", std::chrono::duration<int>(min)));
+}
+
+TEST(chrono_test, special_durations) {
+  EXPECT_EQ(fmt::format("{:%S}", std::chrono::duration<double>(1e20)), "40");
+  auto nan = std::numeric_limits<double>::quiet_NaN();
+  EXPECT_EQ(
+      fmt::format("{:%I %H %M %S %R %r}", std::chrono::duration<double>(nan)),
+      "nan nan nan nan nan:nan nan");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<float, std::exa>(1)),
+            "1Es");
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<float, std::atto>(1)),
+            "1as");
+  EXPECT_EQ(fmt::format("{:%R}", std::chrono::duration<char, std::mega>{2}),
+            "03:33");
+  EXPECT_EQ(fmt::format("{:%T}", std::chrono::duration<char, std::mega>{2}),
+            "03:33:20");
+  EXPECT_EQ(
+      fmt::format("{:.3%S}", std::chrono::duration<float, std::pico>(1.234e12)),
+      "01.234");
+}
+
+TEST(chrono_test, unsigned_duration) {
+  EXPECT_EQ(fmt::format("{}", std::chrono::duration<unsigned>(42)), "42s");
+}
+
+TEST(chrono_test, weekday) {
+  auto loc = get_locale("es_ES.UTF-8");
+  std::locale::global(loc);
+  auto sat = fmt::weekday(6);
+
+  auto tm = std::tm();
+  tm.tm_wday = static_cast<int>(sat.c_encoding());
+
+  EXPECT_EQ(fmt::format("{}", sat), "Sat");
+  EXPECT_EQ(fmt::format("{:%a}", tm), "Sat");
+
+  if (loc != std::locale::classic()) {
+    auto saturdays = std::vector<std::string>{"sáb", "sá."};
+    EXPECT_THAT(saturdays, Contains(fmt::format(loc, "{:L}", sat)));
+    EXPECT_THAT(saturdays, 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 subsecond presision modifier.
+  EXPECT_EQ(fmt::format("{:.6%S}", std::chrono::nanoseconds{1234}),
+            "00.000001");
+  EXPECT_EQ(fmt::format("{:.18%S}", std::chrono::nanoseconds{1234}),
+            "00.000001234000000000");
+  EXPECT_EQ(fmt::format("{:.{}%S}", std::chrono::nanoseconds{1234}, 6),
+            "00.000001");
+  EXPECT_EQ(fmt::format("{:.6%S}", std::chrono::milliseconds{1234}),
+            "01.234000");
+  EXPECT_EQ(fmt::format("{:.6%S}", std::chrono::milliseconds{-1234}),
+            "-01.234000");
+  EXPECT_EQ(fmt::format("{:.3%S}", std::chrono::seconds{1234}), "34.000");
+  EXPECT_EQ(fmt::format("{:.3%S}", std::chrono::hours{1234}), "00.000");
+  EXPECT_EQ(fmt::format("{:.5%S}", dms(1.234)), "00.00123");
+  EXPECT_EQ(fmt::format("{:.8%S}", dms(1.234)), "00.00123400");
+  {
+    // 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);
+    EXPECT_EQ(fmt::format("{:.6%H:%M:%S}", dur), "01:00:01.234000");
+  }
+  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);
+    EXPECT_EQ(fmt::format("{:.3%H:%M:%S}", dur), "-00:01:39.123");
+  }
+  // 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");
+  EXPECT_EQ(fmt::format("{:%S}",
+                        std::chrono::duration<long long, std::ratio<1, 3>>(1)),
+            "00.333333");
+  EXPECT_EQ(fmt::format("{:%S}",
+                        std::chrono::duration<long long, std::ratio<1, 7>>(1)),
+            "00.142857");
+
+  EXPECT_EQ(
+      fmt::format("{:%S}",
+                  std::chrono::duration<signed char, std::ratio<1, 100>>(0x80)),
+      "-01.28");
+
+  EXPECT_EQ(
+      fmt::format("{:%M:%S}",
+                  std::chrono::duration<short, std::ratio<1, 100>>(0x8000)),
+      "-05:27.68");
+
+  // Check that floating point seconds with ratio<1,1> are printed.
+  EXPECT_EQ(fmt::format("{:%S}", std::chrono::duration<double>{1.5}),
+            "01.500000");
+  EXPECT_EQ(fmt::format("{:%M:%S}", std::chrono::duration<double>{-61.25}),
+            "-01:01.250000");
+}
+
+#endif  // FMT_STATIC_THOUSANDS_SEPARATOR
+
+// Disable the utc_clock test for windows, as the icu.dll used for tzdb
+// (time zone database) is not shipped with many windows versions.
+#if FMT_USE_UTC_TIME && !defined(_WIN32)
+TEST(chrono_test, utc_clock) {
+  auto t1 = std::chrono::system_clock::now();
+  auto t1_utc = std::chrono::utc_clock::from_sys(t1);
+  EXPECT_EQ(fmt::format("{:%Y-%m-%d %H:%M:%S}", t1),
+            fmt::format("{:%Y-%m-%d %H:%M:%S}", t1_utc));
+}
+#endif
+
+TEST(chrono_test, timestamp_ratios) {
+  auto t1 =
+      sys_time<std::chrono::milliseconds>(std::chrono::milliseconds(67890));
+  EXPECT_EQ(fmt::format("{:%M:%S}", t1), "01:07.890");
+
+  auto t2 = sys_time<std::chrono::minutes>(std::chrono::minutes(7));
+  EXPECT_EQ(fmt::format("{:%M:%S}", t2), "07:00");
+
+  auto t3 = sys_time<std::chrono::duration<int, std::ratio<9>>>(
+      std::chrono::duration<int, std::ratio<9>>(7));
+  EXPECT_EQ(fmt::format("{:%M:%S}", t3), "01:03");
+
+  auto t4 = sys_time<std::chrono::duration<int, std::ratio<63>>>(
+      std::chrono::duration<int, std::ratio<63>>(1));
+  EXPECT_EQ(fmt::format("{:%M:%S}", t4), "01:03");
+
+  if (sizeof(time_t) > 4) {
+    auto tp =
+        sys_time<std::chrono::milliseconds>(std::chrono::seconds(32503680000));
+    EXPECT_EQ(fmt::format("{:%Y-%m-%d}", tp), "3000-01-01");
+  }
+
+  if (FMT_SAFE_DURATION_CAST) {
+    using years = std::chrono::duration<std::int64_t, std::ratio<31556952>>;
+    auto tp = sys_time<years>(years(std::numeric_limits<std::int64_t>::max()));
+    EXPECT_THROW_MSG((void)fmt::format("{:%Y-%m-%d}", tp), fmt::format_error,
+                     "cannot format duration");
+  }
+}
+
+TEST(chrono_test, timestamp_sub_seconds) {
+  auto t1 = sys_time<std::chrono::duration<long long, std::ratio<1, 3>>>(
+      std::chrono::duration<long long, std::ratio<1, 3>>(4));
+  EXPECT_EQ(fmt::format("{:%S}", t1), "01.333333");
+
+  auto t2 = sys_time<std::chrono::duration<double, std::ratio<1, 3>>>(
+      std::chrono::duration<double, std::ratio<1, 3>>(4));
+  EXPECT_EQ(fmt::format("{:%S}", t2), "01.333333");
+
+  auto t3 = sys_time<std::chrono::seconds>(std::chrono::seconds(2));
+  EXPECT_EQ(fmt::format("{:%S}", t3), "02");
+
+  auto t4 = sys_time<std::chrono::duration<double>>(
+      std::chrono::duration<double, std::ratio<1, 1>>(9.5));
+  EXPECT_EQ(fmt::format("{:%S}", t4), "09.500000");
+
+  auto t5 = sys_time<std::chrono::duration<double>>(
+      std::chrono::duration<double, std::ratio<1, 1>>(9));
+  EXPECT_EQ(fmt::format("{:%S}", t5), "09");
+
+  auto t6 = sys_time<std::chrono::milliseconds>(std::chrono::seconds(1) +
+                                                std::chrono::milliseconds(120));
+  EXPECT_EQ(fmt::format("{:%S}", t6), "01.120");
+
+  auto t7 =
+      sys_time<std::chrono::microseconds>(std::chrono::microseconds(1234567));
+  EXPECT_EQ(fmt::format("{:%S}", t7), "01.234567");
+
+  auto t8 =
+      sys_time<std::chrono::nanoseconds>(std::chrono::nanoseconds(123456789));
+  EXPECT_EQ(fmt::format("{:%S}", t8), "00.123456789");
+
+  auto t9 = std::chrono::time_point_cast<std::chrono::nanoseconds>(
+      std::chrono::system_clock::now());
+  auto t9_sec = std::chrono::time_point_cast<std::chrono::seconds>(t9);
+  auto t9_sub_sec_part = fmt::format("{0:09}", (t9 - t9_sec).count());
+  EXPECT_EQ(fmt::format("{}.{}", strftime_full_utc(t9_sec), t9_sub_sec_part),
+            fmt::format("{:%Y-%m-%d %H:%M:%S}", t9));
+  EXPECT_EQ(fmt::format("{}.{}", strftime_full_utc(t9_sec), t9_sub_sec_part),
+            fmt::format("{:%Y-%m-%d %T}", t9));
+
+  auto t10 =
+      sys_time<std::chrono::milliseconds>(std::chrono::milliseconds(2000));
+  EXPECT_EQ(fmt::format("{:%S}", t10), "02.000");
+
+  auto epoch = sys_time<std::chrono::milliseconds>();
+  auto d = std::chrono::milliseconds(250);
+  EXPECT_EQ(fmt::format("{:%S}", epoch - d), "59.750");
+  EXPECT_EQ(fmt::format("{:%S}", epoch), "00.000");
+  EXPECT_EQ(fmt::format("{:%S}", epoch + d), "00.250");
+}
+
+TEST(chrono_test, glibc_extensions) {
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%0}"), std::chrono::seconds()),
+                   fmt::format_error, "invalid format");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%_}"), std::chrono::seconds()),
+                   fmt::format_error, "invalid format");
+  EXPECT_THROW_MSG((void)fmt::format(runtime("{:%-}"), std::chrono::seconds()),
+                   fmt::format_error, "invalid format");
+
+  {
+    const auto d = std::chrono::hours(1) + std::chrono::minutes(2) +
+                   std::chrono::seconds(3);
+
+    EXPECT_EQ(fmt::format("{:%I,%H,%M,%S}", d), "01,01,02,03");
+    EXPECT_EQ(fmt::format("{:%0I,%0H,%0M,%0S}", d), "01,01,02,03");
+    EXPECT_EQ(fmt::format("{:%_I,%_H,%_M,%_S}", d), " 1, 1, 2, 3");
+    EXPECT_EQ(fmt::format("{:%-I,%-H,%-M,%-S}", d), "1,1,2,3");
+
+    EXPECT_EQ(fmt::format("{:%OI,%OH,%OM,%OS}", d), "01,01,02,03");
+    EXPECT_EQ(fmt::format("{:%0OI,%0OH,%0OM,%0OS}", d), "01,01,02,03");
+    EXPECT_EQ(fmt::format("{:%_OI,%_OH,%_OM,%_OS}", d), " 1, 1, 2, 3");
+    EXPECT_EQ(fmt::format("{:%-OI,%-OH,%-OM,%-OS}", d), "1,1,2,3");
+  }
+
+  {
+    const auto tm = make_tm(1970, 1, 1, 1, 2, 3);
+    EXPECT_EQ(fmt::format("{:%I,%H,%M,%S}", tm), "01,01,02,03");
+    EXPECT_EQ(fmt::format("{:%0I,%0H,%0M,%0S}", tm), "01,01,02,03");
+    EXPECT_EQ(fmt::format("{:%_I,%_H,%_M,%_S}", tm), " 1, 1, 2, 3");
+    EXPECT_EQ(fmt::format("{:%-I,%-H,%-M,%-S}", tm), "1,1,2,3");
+
+    EXPECT_EQ(fmt::format("{:%OI,%OH,%OM,%OS}", tm), "01,01,02,03");
+    EXPECT_EQ(fmt::format("{:%0OI,%0OH,%0OM,%0OS}", tm), "01,01,02,03");
+    EXPECT_EQ(fmt::format("{:%_OI,%_OH,%_OM,%_OS}", tm), " 1, 1, 2, 3");
+    EXPECT_EQ(fmt::format("{:%-OI,%-OH,%-OM,%-OS}", tm), "1,1,2,3");
+  }
+
+  {
+    const auto d = std::chrono::seconds(3) + std::chrono::milliseconds(140);
+    EXPECT_EQ(fmt::format("{:%S}", d), "03.140");
+    EXPECT_EQ(fmt::format("{:%0S}", d), "03.140");
+    EXPECT_EQ(fmt::format("{:%_S}", d), " 3.140");
+    EXPECT_EQ(fmt::format("{:%-S}", d), "3.140");
+  }
+
+  {
+    const auto d = std::chrono::duration<double>(3.14);
+    EXPECT_EQ(fmt::format("{:%S}", d), "03.140000");
+    EXPECT_EQ(fmt::format("{:%0S}", d), "03.140000");
+    EXPECT_EQ(fmt::format("{:%_S}", d), " 3.140000");
+    EXPECT_EQ(fmt::format("{:%-S}", d), "3.140000");
+  }
+}
+
+TEST(chrono_test, out_of_range) {
+  auto d = std::chrono::duration<unsigned long, std::giga>(538976288);
+  EXPECT_THROW((void)fmt::format("{:%j}", d), fmt::format_error);
+}

test/color-test.cc

@@ -0,0 +1,72 @@
+// Formatting library for C++ - color tests
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include "fmt/color.h"
+
+#include <iterator>  // std::back_inserter
+
+#include "gtest-extra.h"  // EXPECT_WRITE
+
+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::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(
+      fmt::format(fg(fmt::color::blue) | fmt::emphasis::bold, "blue/bold"),
+      "\x1b[1m\x1b[38;2;000;000;255mblue/bold\x1b[0m");
+  EXPECT_EQ(fmt::format(fmt::emphasis::bold, "bold error"),
+            "\x1b[1mbold error\x1b[0m");
+  EXPECT_EQ(fmt::format(fg(fmt::color::blue), "blue log"),
+            "\x1b[38;2;000;000;255mblue log\x1b[0m");
+  EXPECT_EQ(fmt::format(fmt::text_style(), "hi"), "hi");
+  EXPECT_EQ(fmt::format(fg(fmt::terminal_color::red), "tred"),
+            "\x1b[31mtred\x1b[0m");
+  EXPECT_EQ(fmt::format(bg(fmt::terminal_color::cyan), "tcyan"),
+            "\x1b[46mtcyan\x1b[0m");
+  EXPECT_EQ(fmt::format(fg(fmt::terminal_color::bright_green), "tbgreen"),
+            "\x1b[92mtbgreen\x1b[0m");
+  EXPECT_EQ(fmt::format(bg(fmt::terminal_color::bright_magenta), "tbmagenta"),
+            "\x1b[105mtbmagenta\x1b[0m");
+  EXPECT_EQ(fmt::format(fg(fmt::terminal_color::red), "{}", "foo"),
+            "\x1b[31mfoo\x1b[0m");
+  EXPECT_EQ(fmt::format("{}{}", fmt::styled("red", fg(fmt::color::red)),
+                        fmt::styled("bold", fmt::emphasis::bold)),
+            "\x1b[38;2;255;000;000mred\x1b[0m\x1b[1mbold\x1b[0m");
+  EXPECT_EQ(fmt::format("{}", fmt::styled("bar", fg(fmt::color::blue) |
+                                                     fmt::emphasis::underline)),
+            "\x1b[4m\x1b[38;2;000;000;255mbar\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

@@ -0,0 +1,241 @@
+# Test if compile errors are produced where necessary.
+
+cmake_minimum_required(VERSION 3.8...3.25)
+project(compile-error-test CXX)
+
+set(fmt_headers "
+  #include <fmt/format.h>
+  #include <fmt/xchar.h>
+  #include <fmt/ostream.h>
+  #include <iostream>
+")
+
+set(error_test_names "")
+set(non_error_test_content "")
+
+# 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 ()
+
+# 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 3.8...3.25)
+    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 ()
+
+
+# check if the source file skeleton compiles
+expect_compile(check "")
+expect_compile(check-error "compilation_error" ERROR)
+
+# Formatting a wide character with a narrow format string is forbidden.
+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(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(narrow-string-wide-format-string "fmt::format(L\"{}\", L\"foo\");")
+expect_compile(narrow-string-wide-format-string-error "fmt::format(L\"{}\", \"foo\");" 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)
+
+# Formatting an unformattable argument should always be a compile time error
+expect_compile(format-lots-of-arguments-with-unformattable "
+  struct E {};
+  fmt::format(\"\", 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, E());
+" ERROR)
+expect_compile(format-lots-of-arguments-with-function "
+  void (*f)();
+  fmt::format(\"\", 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, f);
+" ERROR)
+
+# Check if user-defined literals are available
+include(CheckCXXSourceCompiles)
+set(CMAKE_REQUIRED_FLAGS ${CXX_STANDARD_FLAG})
+check_cxx_source_compiles("
+  void operator\"\" _udl(long double);
+  int main() {}"
+  SUPPORTS_USER_DEFINED_LITERALS)
+set(CMAKE_REQUIRED_FLAGS )
+if (NOT SUPPORTS_USER_DEFINED_LITERALS)
+  set (SUPPORTS_USER_DEFINED_LITERALS OFF)
+endif ()
+
+# Make sure that compiler features detected in the header
+# match the features detected in CMake.
+if (SUPPORTS_USER_DEFINED_LITERALS)
+  set(supports_udl 1)
+else ()
+  set(supports_udl 0)
+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)
+  expect_compile(print-string-number-spec-error "
+    #ifdef FMT_HAS_CONSTEVAL
+      fmt::print(\"{:d}\", \"I am not a number\");
+    #else
+      #error
+    #endif
+  " ERROR)
+  expect_compile(print-stream-string-number-spec-error "
+  #ifdef FMT_HAS_CONSTEVAL
+    fmt::print(std::cout, \"{: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_ARGS
+      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_ARGS
+      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 +1,63 @@
+// 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 "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 && FMT_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

@@ -0,0 +1,377 @@
+// 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 <type_traits>
+
+#include "fmt/chrono.h"
+#include "gmock/gmock.h"
+#include "gtest-extra.h"
+
+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(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));
+}
+
+struct type_with_get {
+  template <int> friend void get(type_with_get);
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<type_with_get> : formatter<int> {
+  template <typename FormatContext>
+  auto format(type_with_get, FormatContext& ctx) -> decltype(ctx.out()) {
+    return formatter<int>::format(42, ctx);
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(compile_test, compile_type_with_get) {
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), type_with_get()));
+}
+
+#if defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+struct test_formattable {};
+
+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));
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42ull));
+  EXPECT_EQ("true", fmt::format(FMT_COMPILE("{}"), true));
+  EXPECT_EQ("x", fmt::format(FMT_COMPILE("{}"), 'x'));
+  EXPECT_EQ("4.2", fmt::format(FMT_COMPILE("{}"), 4.2));
+  EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), "foo"));
+  EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), std::string("foo")));
+  EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), test_formattable()));
+  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(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(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_ARGS
+  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, join) {
+  unsigned char data[] = {0x1, 0x2, 0xaf};
+  EXPECT_EQ("0102af", fmt::format(FMT_COMPILE("{:02x}"), fmt::join(data, "")));
+}
+
+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(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);
+}
+
+#  ifdef __cpp_lib_bit_cast
+TEST(compile_test, constexpr_formatted_size) {
+  FMT_CONSTEXPR20 size_t size = fmt::formatted_size(FMT_COMPILE("{}"), 42);
+  EXPECT_EQ(size, 2);
+  FMT_CONSTEXPR20 size_t hex_size =
+      fmt::formatted_size(FMT_COMPILE("{:x}"), 15);
+  EXPECT_EQ(hex_size, 1);
+  FMT_CONSTEXPR20 size_t binary_size =
+      fmt::formatted_size(FMT_COMPILE("{:b}"), 15);
+  EXPECT_EQ(binary_size, 4);
+  FMT_CONSTEXPR20 size_t padded_size =
+      fmt::formatted_size(FMT_COMPILE("{:*^6}"), 42);
+  EXPECT_EQ(padded_size, 6);
+  FMT_CONSTEXPR20 size_t float_size =
+      fmt::formatted_size(FMT_COMPILE("{:.3}"), 12.345);
+  EXPECT_EQ(float_size, 4);
+  FMT_CONSTEXPR20 size_t str_size =
+      fmt::formatted_size(FMT_COMPILE("{:s}"), "abc");
+  EXPECT_EQ(str_size, 3);
+}
+#  endif
+
+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_ARGS
+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
+
+// MSVS 2019 19.29.30145.0 - Support C++20 and OK.
+// MSVS 2022 19.32.31332.0, 19.37.32826.1 - compile-test.cc(362,3): fatal error
+// C1001: Internal compiler error.
+//  (compiler file
+//  'D:\a\_work\1\s\src\vctools\Compiler\CxxFE\sl\p1\c\constexpr\constexpr.cpp',
+//  line 8635)
+#if (FMT_CPLUSPLUS >= 202002L ||                                \
+     (FMT_CPLUSPLUS >= 201709L && FMT_GCC_VERSION >= 1002)) &&  \
+    ((!defined(_GLIBCXX_RELEASE) || _GLIBCXX_RELEASE >= 10) &&  \
+     (!defined(_LIBCPP_VERSION) || _LIBCPP_VERSION >= 10000) && \
+     (!FMT_MSC_VERSION ||                                       \
+      (FMT_MSC_VERSION >= 1928 && FMT_MSC_VERSION < 1930))) &&  \
+    defined(__cpp_lib_is_constant_evaluated)
+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/compile-test/CMakeLists.txt

@@ -1,77 +0,0 @@
-# Test if compile errors are produced where necessary.
-
-cmake_minimum_required(VERSION 2.8)
-
-include(CheckCXXSourceCompiles)
-set(CMAKE_REQUIRED_INCLUDES ${CMAKE_CURRENT_SOURCE_DIR}/../../include)
-set(CMAKE_REQUIRED_FLAGS ${CPP14_FLAG})
-
-function (generate_source result fragment)
-  set(${result} "
-  #define FMT_HEADER_ONLY 1
-  #include \"fmt/format.h\"
-  int main() {
-    ${fragment}
-  }
-  " PARENT_SCOPE)
-endfunction ()
-
-function (expect_compile code)
-  generate_source(source "${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 ${error_msg})
-  endif ()
-endfunction ()
-
-function (expect_compile_error code)
-  generate_source(source "${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("")
-
-# Formatting a wide character with a narrow format string is forbidden.
-expect_compile_error("fmt::format(\"{}\", L'a');")
-
-# Formatting a wide string with a narrow format string is forbidden.
-expect_compile_error("fmt::format(\"{}\", L\"foo\");")
-
-# 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\");")
-
-# Formatting a wide string with a narrow format string is forbidden.
-expect_compile_error("
-  struct S {
-    operator std::string() const { return std::string(); }
-  };
-  fmt::format(\"{}\", S());
-")
-
-# Make sure that compiler features detected in the header
-# match the features detected in CMake.
-if (SUPPORTS_USER_DEFINED_LITERALS)
-  set(supports_udl 1)
-else ()
-  set(supports_udl 0)
-endif ()
-expect_compile("#if FMT_USE_USER_DEFINED_LITERALS != ${supports_udl}
-                # error
-                #endif")

test/core-test.cc

@@ -0,0 +1,858 @@
+// Formatting library for C++ - core tests
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+// clang-format off
+#include "test-assert.h"
+// clang-format on
+
+#include "fmt/core.h"
+
+#include <algorithm>    // std::copy_n
+#include <climits>      // INT_MAX
+#include <cstring>      // std::strlen
+#include <functional>   // std::equal_to
+#include <iterator>     // std::back_insert_iterator
+#include <limits>       // std::numeric_limits
+#include <string>       // std::string
+#include <type_traits>  // std::is_same
+
+#include "gmock/gmock.h"
+
+using fmt::string_view;
+using fmt::detail::buffer;
+
+using testing::_;
+using testing::Invoke;
+using testing::Return;
+
+#ifdef FMT_FORMAT_H_
+#  error core-test includes format.h
+#endif
+
+TEST(string_view_test, value_type) {
+  static_assert(std::is_same<string_view::value_type, char>::value, "");
+}
+
+TEST(string_view_test, ctor) {
+  EXPECT_STREQ("abc", fmt::string_view("abc").data());
+  EXPECT_EQ(3u, fmt::string_view("abc").size());
+
+  EXPECT_STREQ("defg", fmt::string_view(std::string("defg")).data());
+  EXPECT_EQ(4u, fmt::string_view(std::string("defg")).size());
+}
+
+TEST(string_view_test, length) {
+  // Test that string_view::size() returns string length, not buffer size.
+  char str[100] = "some string";
+  EXPECT_EQ(std::strlen(str), string_view(str).size());
+  EXPECT_LT(std::strlen(str), sizeof(str));
+}
+
+// Check string_view's comparison operator.
+template <template <typename> class Op> void check_op() {
+  const char* inputs[] = {"foo", "fop", "fo"};
+  size_t num_inputs = sizeof(inputs) / sizeof(*inputs);
+  for (size_t i = 0; i < num_inputs; ++i) {
+    for (size_t j = 0; j < num_inputs; ++j) {
+      string_view lhs(inputs[i]), rhs(inputs[j]);
+      EXPECT_EQ(Op<int>()(lhs.compare(rhs), 0), Op<string_view>()(lhs, rhs));
+    }
+  }
+}
+
+TEST(string_view_test, compare) {
+  EXPECT_EQ(string_view("foo").compare(string_view("foo")), 0);
+  EXPECT_GT(string_view("fop").compare(string_view("foo")), 0);
+  EXPECT_LT(string_view("foo").compare(string_view("fop")), 0);
+  EXPECT_GT(string_view("foo").compare(string_view("fo")), 0);
+  EXPECT_LT(string_view("fo").compare(string_view("foo")), 0);
+
+  EXPECT_TRUE(string_view("foo").starts_with('f'));
+  EXPECT_FALSE(string_view("foo").starts_with('o'));
+  EXPECT_FALSE(string_view().starts_with('o'));
+
+  EXPECT_TRUE(string_view("foo").starts_with("fo"));
+  EXPECT_TRUE(string_view("foo").starts_with("foo"));
+  EXPECT_FALSE(string_view("foo").starts_with("fooo"));
+  EXPECT_FALSE(string_view().starts_with("fooo"));
+
+  check_op<std::equal_to>();
+  check_op<std::not_equal_to>();
+  check_op<std::less>();
+  check_op<std::less_equal>();
+  check_op<std::greater>();
+  check_op<std::greater_equal>();
+}
+
+TEST(core_test, is_output_iterator) {
+  EXPECT_TRUE((fmt::detail::is_output_iterator<char*, char>::value));
+  EXPECT_FALSE((fmt::detail::is_output_iterator<const char*, char>::value));
+  EXPECT_FALSE((fmt::detail::is_output_iterator<std::string, char>::value));
+  EXPECT_TRUE(
+      (fmt::detail::is_output_iterator<std::back_insert_iterator<std::string>,
+                                       char>::value));
+  EXPECT_TRUE(
+      (fmt::detail::is_output_iterator<std::string::iterator, char>::value));
+  EXPECT_FALSE((fmt::detail::is_output_iterator<std::string::const_iterator,
+                                                char>::value));
+}
+
+TEST(core_test, buffer_appender) {
+  // back_insert_iterator is not default-constructible before C++20, so
+  // buffer_appender can only be default-constructible when back_insert_iterator
+  // is.
+  static_assert(
+      std::is_default_constructible<
+          std::back_insert_iterator<fmt::detail::buffer<char>>>::value ==
+          std::is_default_constructible<
+              fmt::detail::buffer_appender<char>>::value,
+      "");
+
+#ifdef __cpp_lib_ranges
+  static_assert(std::output_iterator<fmt::detail::buffer_appender<char>, char>);
+#endif
+}
+
+#if !FMT_GCC_VERSION || FMT_GCC_VERSION >= 470
+TEST(buffer_test, noncopyable) {
+  EXPECT_FALSE(std::is_copy_constructible<buffer<char>>::value);
+#  if !FMT_MSC_VERSION
+  // std::is_copy_assignable is broken in MSVC2013.
+  EXPECT_FALSE(std::is_copy_assignable<buffer<char>>::value);
+#  endif
+}
+
+TEST(buffer_test, nonmoveable) {
+  EXPECT_FALSE(std::is_move_constructible<buffer<char>>::value);
+#  if !FMT_MSC_VERSION
+  // std::is_move_assignable is broken in MSVC2013.
+  EXPECT_FALSE(std::is_move_assignable<buffer<char>>::value);
+#  endif
+}
+#endif
+
+TEST(buffer_test, indestructible) {
+  static_assert(!std::is_destructible<fmt::detail::buffer<int>>(),
+                "buffer's destructor is protected");
+}
+
+template <typename T> struct mock_buffer final : buffer<T> {
+  MOCK_METHOD(size_t, do_grow, (size_t));
+
+  void grow(size_t capacity) override {
+    this->set(this->data(), do_grow(capacity));
+  }
+
+  mock_buffer(T* data = nullptr, size_t buf_capacity = 0) {
+    this->set(data, buf_capacity);
+    ON_CALL(*this, do_grow(_)).WillByDefault(Invoke([](size_t capacity) {
+      return capacity;
+    }));
+  }
+};
+
+TEST(buffer_test, ctor) {
+  {
+    mock_buffer<int> buffer;
+    EXPECT_EQ(nullptr, buffer.data());
+    EXPECT_EQ(static_cast<size_t>(0), buffer.size());
+    EXPECT_EQ(static_cast<size_t>(0), buffer.capacity());
+  }
+  {
+    int dummy;
+    mock_buffer<int> buffer(&dummy);
+    EXPECT_EQ(&dummy, &buffer[0]);
+    EXPECT_EQ(static_cast<size_t>(0), buffer.size());
+    EXPECT_EQ(static_cast<size_t>(0), buffer.capacity());
+  }
+  {
+    int dummy;
+    size_t capacity = std::numeric_limits<size_t>::max();
+    mock_buffer<int> buffer(&dummy, capacity);
+    EXPECT_EQ(&dummy, &buffer[0]);
+    EXPECT_EQ(static_cast<size_t>(0), buffer.size());
+    EXPECT_EQ(capacity, buffer.capacity());
+  }
+}
+
+TEST(buffer_test, access) {
+  char data[10];
+  mock_buffer<char> buffer(data, sizeof(data));
+  buffer[0] = 11;
+  EXPECT_EQ(11, buffer[0]);
+  buffer[3] = 42;
+  EXPECT_EQ(42, *(&buffer[0] + 3));
+  const fmt::detail::buffer<char>& const_buffer = buffer;
+  EXPECT_EQ(42, const_buffer[3]);
+}
+
+TEST(buffer_test, try_resize) {
+  char data[123];
+  mock_buffer<char> buffer(data, sizeof(data));
+  buffer[10] = 42;
+  EXPECT_EQ(42, buffer[10]);
+  buffer.try_resize(20);
+  EXPECT_EQ(20u, buffer.size());
+  EXPECT_EQ(123u, buffer.capacity());
+  EXPECT_EQ(42, buffer[10]);
+  buffer.try_resize(5);
+  EXPECT_EQ(5u, buffer.size());
+  EXPECT_EQ(123u, buffer.capacity());
+  EXPECT_EQ(42, buffer[10]);
+  // Check if try_resize calls grow.
+  EXPECT_CALL(buffer, do_grow(124));
+  buffer.try_resize(124);
+  EXPECT_CALL(buffer, do_grow(200));
+  buffer.try_resize(200);
+}
+
+TEST(buffer_test, try_resize_partial) {
+  char data[10];
+  mock_buffer<char> buffer(data, sizeof(data));
+  EXPECT_CALL(buffer, do_grow(20)).WillOnce(Return(15));
+  buffer.try_resize(20);
+  EXPECT_EQ(buffer.capacity(), 15);
+  EXPECT_EQ(buffer.size(), 15);
+}
+
+TEST(buffer_test, clear) {
+  mock_buffer<char> buffer;
+  EXPECT_CALL(buffer, do_grow(20));
+  buffer.try_resize(20);
+  buffer.try_resize(0);
+  EXPECT_EQ(static_cast<size_t>(0), buffer.size());
+  EXPECT_EQ(20u, buffer.capacity());
+}
+
+TEST(buffer_test, append) {
+  char data[15];
+  mock_buffer<char> buffer(data, 10);
+  auto test = "test";
+  buffer.append(test, test + 5);
+  EXPECT_STREQ(test, &buffer[0]);
+  EXPECT_EQ(5u, buffer.size());
+  buffer.try_resize(10);
+  EXPECT_CALL(buffer, do_grow(12));
+  buffer.append(test, test + 2);
+  EXPECT_EQ('t', buffer[10]);
+  EXPECT_EQ('e', buffer[11]);
+  EXPECT_EQ(12u, buffer.size());
+}
+
+TEST(buffer_test, append_partial) {
+  char data[10];
+  mock_buffer<char> buffer(data, sizeof(data));
+  testing::InSequence seq;
+  EXPECT_CALL(buffer, do_grow(15)).WillOnce(Return(10));
+  EXPECT_CALL(buffer, do_grow(15)).WillOnce(Invoke([&buffer](size_t) {
+    EXPECT_EQ(fmt::string_view(buffer.data(), buffer.size()), "0123456789");
+    buffer.clear();
+    return 10;
+  }));
+  auto test = "0123456789abcde";
+  buffer.append(test, test + 15);
+}
+
+TEST(buffer_test, append_allocates_enough_storage) {
+  char data[19];
+  mock_buffer<char> buffer(data, 10);
+  auto test = "abcdefgh";
+  buffer.try_resize(10);
+  EXPECT_CALL(buffer, do_grow(19));
+  buffer.append(test, test + 9);
+}
+
+struct custom_context {
+  using char_type = char;
+  using parse_context_type = fmt::format_parse_context;
+
+  bool called = false;
+
+  template <typename T> struct formatter_type {
+    FMT_CONSTEXPR auto parse(fmt::format_parse_context& ctx) -> decltype(ctx.begin()) {
+      return ctx.begin();
+    }
+
+    const char* format(const T&, custom_context& ctx) {
+      ctx.called = true;
+      return nullptr;
+    }
+  };
+
+  void advance_to(const char*) {}
+};
+
+struct test_struct {};
+
+FMT_BEGIN_NAMESPACE
+template <typename Char> struct formatter<test_struct, Char> {
+  FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  auto format(test_struct, format_context& ctx) const -> decltype(ctx.out()) {
+    auto test = string_view("test");
+    return std::copy_n(test.data(), test.size(), ctx.out());
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(arg_test, format_args) {
+  auto args = fmt::format_args();
+  EXPECT_FALSE(args.get(1));
+}
+
+TEST(arg_test, make_value_with_custom_context) {
+  auto t = test_struct();
+  auto arg = fmt::detail::value<custom_context>(
+      fmt::detail::arg_mapper<custom_context>().map(t));
+  auto ctx = custom_context();
+  auto parse_ctx = fmt::format_parse_context("");
+  arg.custom.format(&t, parse_ctx, ctx);
+  EXPECT_TRUE(ctx.called);
+}
+
+// Use a unique result type to make sure that there are no undesirable
+// conversions.
+struct test_result {};
+
+template <typename T> struct mock_visitor {
+  template <typename U> struct result { using type = test_result; };
+
+  mock_visitor() {
+    ON_CALL(*this, visit(_)).WillByDefault(Return(test_result()));
+  }
+
+  MOCK_METHOD(test_result, visit, (T));
+  MOCK_METHOD(void, unexpected, ());
+
+  auto operator()(T value) -> test_result { return visit(value); }
+
+  template <typename U> auto operator()(U) -> test_result {
+    unexpected();
+    return test_result();
+  }
+};
+
+template <typename T> struct visit_type { using type = T; };
+
+#define VISIT_TYPE(type_, visit_type_) \
+  template <> struct visit_type<type_> { using type = visit_type_; }
+
+VISIT_TYPE(signed char, int);
+VISIT_TYPE(unsigned char, unsigned);
+VISIT_TYPE(short, int);
+VISIT_TYPE(unsigned short, unsigned);
+
+#if LONG_MAX == INT_MAX
+VISIT_TYPE(long, int);
+VISIT_TYPE(unsigned long, unsigned);
+#else
+VISIT_TYPE(long, long long);
+VISIT_TYPE(unsigned long, unsigned long long);
+#endif
+
+#define CHECK_ARG(Char, expected, value)                                  \
+  {                                                                       \
+    testing::StrictMock<mock_visitor<decltype(expected)>> visitor;        \
+    EXPECT_CALL(visitor, visit(expected));                                \
+    using iterator = std::back_insert_iterator<buffer<Char>>;             \
+    auto var = value;                                                     \
+    fmt::visit_format_arg(                                                \
+        visitor,                                                          \
+        fmt::detail::make_arg<fmt::basic_format_context<iterator, Char>>( \
+            var));                                                        \
+  }
+
+#define CHECK_ARG_SIMPLE(value)                             \
+  {                                                         \
+    using value_type = decltype(value);                     \
+    typename visit_type<value_type>::type expected = value; \
+    CHECK_ARG(char, expected, value)                        \
+    CHECK_ARG(wchar_t, expected, value)                     \
+  }
+
+template <typename T> class numeric_arg_test : public testing::Test {};
+
+using test_types =
+    testing::Types<bool, signed char, unsigned char, short, unsigned short, int,
+                   unsigned, long, unsigned long, long long, unsigned long long,
+                   float, double, long double>;
+TYPED_TEST_SUITE(numeric_arg_test, test_types);
+
+template <typename T, fmt::enable_if_t<std::is_integral<T>::value, int> = 0>
+auto test_value() -> T {
+  return static_cast<T>(42);
+}
+
+template <typename T,
+          fmt::enable_if_t<std::is_floating_point<T>::value, int> = 0>
+auto test_value() -> T {
+  return static_cast<T>(4.2);
+}
+
+TYPED_TEST(numeric_arg_test, make_and_visit) {
+  CHECK_ARG_SIMPLE(test_value<TypeParam>());
+  CHECK_ARG_SIMPLE(std::numeric_limits<TypeParam>::min());
+  CHECK_ARG_SIMPLE(std::numeric_limits<TypeParam>::max());
+}
+
+TEST(arg_test, char_arg) { CHECK_ARG(char, 'a', 'a'); }
+
+TEST(arg_test, string_arg) {
+  char str_data[] = "test";
+  char* str = str_data;
+  const char* cstr = str;
+  CHECK_ARG(char, cstr, str);
+
+  auto sv = fmt::string_view(str);
+  CHECK_ARG(char, sv, std::string(str));
+}
+
+TEST(arg_test, wstring_arg) {
+  wchar_t str_data[] = L"test";
+  wchar_t* str = str_data;
+  const wchar_t* cstr = str;
+
+  auto sv = fmt::basic_string_view<wchar_t>(str);
+  CHECK_ARG(wchar_t, cstr, str);
+  CHECK_ARG(wchar_t, cstr, cstr);
+  CHECK_ARG(wchar_t, sv, std::wstring(str));
+  CHECK_ARG(wchar_t, sv, fmt::basic_string_view<wchar_t>(str));
+}
+
+TEST(arg_test, pointer_arg) {
+  void* p = nullptr;
+  const void* cp = nullptr;
+  CHECK_ARG(char, cp, p);
+  CHECK_ARG(wchar_t, cp, p);
+  CHECK_ARG_SIMPLE(cp);
+}
+
+struct check_custom {
+  auto operator()(fmt::basic_format_arg<fmt::format_context>::handle h) const
+      -> test_result {
+    struct test_buffer final : fmt::detail::buffer<char> {
+      char data[10];
+      test_buffer() : fmt::detail::buffer<char>(data, 0, 10) {}
+      void grow(size_t) override {}
+    } buffer;
+    auto parse_ctx = fmt::format_parse_context("");
+    auto ctx = fmt::format_context(fmt::detail::buffer_appender<char>(buffer),
+                                   fmt::format_args());
+    h.format(parse_ctx, ctx);
+    EXPECT_EQ("test", std::string(buffer.data, buffer.size()));
+    return test_result();
+  }
+};
+
+TEST(arg_test, custom_arg) {
+  auto test = test_struct();
+  using visitor =
+      mock_visitor<fmt::basic_format_arg<fmt::format_context>::handle>;
+  auto&& v = testing::StrictMock<visitor>();
+  EXPECT_CALL(v, visit(_)).WillOnce(Invoke(check_custom()));
+  fmt::visit_format_arg(v, fmt::detail::make_arg<fmt::format_context>(test));
+}
+
+TEST(arg_test, visit_invalid_arg) {
+  auto&& visitor = testing::StrictMock<mock_visitor<fmt::monostate>>();
+  EXPECT_CALL(visitor, visit(_));
+  auto arg = fmt::basic_format_arg<fmt::format_context>();
+  fmt::visit_format_arg(visitor, arg);
+}
+
+#if FMT_USE_CONSTEXPR
+
+enum class arg_id_result { none, empty, index, name };
+struct test_arg_id_handler {
+  arg_id_result res = arg_id_result::none;
+  int index = 0;
+  string_view name;
+
+  constexpr void on_auto() { res = arg_id_result::empty; }
+
+  constexpr void on_index(int i) {
+    res = arg_id_result::index;
+    index = i;
+  }
+
+  constexpr void on_name(string_view n) {
+    res = arg_id_result::name;
+    name = n;
+  }
+};
+
+template <size_t N>
+constexpr test_arg_id_handler parse_arg_id(const char (&s)[N]) {
+  auto h = test_arg_id_handler();
+  fmt::detail::parse_arg_id(s, s + N, h);
+  return h;
+}
+
+TEST(core_test, constexpr_parse_arg_id) {
+  static_assert(parse_arg_id(":").res == arg_id_result::empty, "");
+  static_assert(parse_arg_id("}").res == arg_id_result::empty, "");
+  static_assert(parse_arg_id("42:").res == arg_id_result::index, "");
+  static_assert(parse_arg_id("42:").index == 42, "");
+  static_assert(parse_arg_id("foo:").res == arg_id_result::name, "");
+  static_assert(parse_arg_id("foo:").name.size() == 3, "");
+}
+
+template <size_t N> constexpr auto parse_test_specs(const char (&s)[N]) {
+  auto ctx = fmt::detail::compile_parse_context<char>(fmt::string_view(s, N),
+                                                      43, nullptr);
+  auto specs = fmt::detail::dynamic_format_specs<>();
+  fmt::detail::parse_format_specs(s, s + N - 1, specs, ctx,
+                                  fmt::detail::type::float_type);
+  return specs;
+}
+
+TEST(core_test, constexpr_parse_format_specs) {
+  static_assert(parse_test_specs("<").align == fmt::align::left, "");
+  static_assert(parse_test_specs("*^").fill[0] == '*', "");
+  static_assert(parse_test_specs("+").sign == fmt::sign::plus, "");
+  static_assert(parse_test_specs("-").sign == fmt::sign::minus, "");
+  static_assert(parse_test_specs(" ").sign == fmt::sign::space, "");
+  static_assert(parse_test_specs("#").alt, "");
+  static_assert(parse_test_specs("0").align == fmt::align::numeric, "");
+  static_assert(parse_test_specs("L").localized, "");
+  static_assert(parse_test_specs("42").width == 42, "");
+  static_assert(parse_test_specs("{42}").width_ref.val.index == 42, "");
+  static_assert(parse_test_specs(".42").precision == 42, "");
+  static_assert(parse_test_specs(".{42}").precision_ref.val.index == 42, "");
+  static_assert(
+      parse_test_specs("f").type == fmt::presentation_type::fixed_lower, "");
+}
+
+struct test_format_string_handler {
+  constexpr void on_text(const char*, const char*) {}
+
+  constexpr auto on_arg_id() -> int { return 0; }
+
+  template <typename T> constexpr auto on_arg_id(T) -> int { return 0; }
+
+  constexpr void on_replacement_field(int, const char*) {}
+
+  constexpr auto on_format_specs(int, const char* begin, const char*) -> const
+      char* {
+    return begin;
+  }
+
+  constexpr void on_error(const char*) { error = true; }
+
+  bool error = false;
+};
+
+template <size_t N> constexpr bool parse_string(const char (&s)[N]) {
+  auto h = test_format_string_handler();
+  fmt::detail::parse_format_string<true>(fmt::string_view(s, N - 1), h);
+  return !h.error;
+}
+
+TEST(core_test, constexpr_parse_format_string) {
+  static_assert(parse_string("foo"), "");
+  static_assert(!parse_string("}"), "");
+  static_assert(parse_string("{}"), "");
+  static_assert(parse_string("{42}"), "");
+  static_assert(parse_string("{foo}"), "");
+  static_assert(parse_string("{:}"), "");
+}
+#endif  // FMT_USE_CONSTEXPR
+
+struct enabled_formatter {};
+struct enabled_ptr_formatter {};
+struct disabled_formatter {};
+struct disabled_formatter_convertible {
+  operator int() const { return 42; }
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<enabled_formatter> {
+  FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+  auto format(enabled_formatter, format_context& ctx) const
+      -> decltype(ctx.out()) {
+    return ctx.out();
+  }
+};
+
+template <> struct formatter<enabled_ptr_formatter*> {
+  FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+  auto format(enabled_ptr_formatter*, format_context& ctx) const
+      -> decltype(ctx.out()) {
+    return ctx.out();
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(core_test, has_formatter) {
+  using fmt::has_formatter;
+  using context = fmt::format_context;
+  static_assert(has_formatter<enabled_formatter, context>::value, "");
+  static_assert(!has_formatter<disabled_formatter, context>::value, "");
+  static_assert(!has_formatter<disabled_formatter_convertible, context>::value,
+                "");
+}
+
+struct const_formattable {};
+struct nonconst_formattable {};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<const_formattable> {
+  FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  auto format(const const_formattable&, format_context& ctx)
+      -> decltype(ctx.out()) {
+    auto test = string_view("test");
+    return std::copy_n(test.data(), test.size(), ctx.out());
+  }
+};
+
+template <> struct formatter<nonconst_formattable> {
+  FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  auto format(nonconst_formattable&, format_context& ctx)
+      -> decltype(ctx.out()) {
+    auto test = string_view("test");
+    return std::copy_n(test.data(), test.size(), ctx.out());
+  }
+};
+FMT_END_NAMESPACE
+
+struct convertible_to_pointer {
+  operator const int*() const { return nullptr; }
+};
+
+struct convertible_to_pointer_formattable {
+  operator const int*() const { return nullptr; }
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<convertible_to_pointer_formattable> {
+  FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  auto format(convertible_to_pointer_formattable, format_context& ctx) const
+      -> decltype(ctx.out()) {
+    auto test = string_view("test");
+    return std::copy_n(test.data(), test.size(), ctx.out());
+  }
+};
+FMT_END_NAMESPACE
+
+enum class unformattable_scoped_enum {};
+
+TEST(core_test, is_formattable) {
+  static_assert(!fmt::is_formattable<wchar_t>::value, "");
+#ifdef __cpp_char8_t
+  static_assert(!fmt::is_formattable<char8_t>::value, "");
+#endif
+  static_assert(!fmt::is_formattable<char16_t>::value, "");
+  static_assert(!fmt::is_formattable<char32_t>::value, "");
+  static_assert(!fmt::is_formattable<signed char*>::value, "");
+  static_assert(!fmt::is_formattable<unsigned char*>::value, "");
+  static_assert(!fmt::is_formattable<const signed char*>::value, "");
+  static_assert(!fmt::is_formattable<const unsigned char*>::value, "");
+  static_assert(!fmt::is_formattable<const wchar_t*>::value, "");
+  static_assert(!fmt::is_formattable<const wchar_t[3]>::value, "");
+  static_assert(!fmt::is_formattable<fmt::basic_string_view<wchar_t>>::value,
+                "");
+  static_assert(fmt::is_formattable<enabled_formatter>::value, "");
+  static_assert(!fmt::is_formattable<enabled_ptr_formatter*>::value, "");
+  static_assert(!fmt::is_formattable<disabled_formatter>::value, "");
+  static_assert(!fmt::is_formattable<disabled_formatter_convertible>::value,
+                "");
+
+  static_assert(fmt::is_formattable<const_formattable&>::value, "");
+  static_assert(fmt::is_formattable<const const_formattable&>::value, "");
+
+  static_assert(fmt::is_formattable<nonconst_formattable&>::value, "");
+#if !FMT_MSC_VERSION || FMT_MSC_VERSION >= 1910
+  static_assert(!fmt::is_formattable<const nonconst_formattable&>::value, "");
+#endif
+
+  static_assert(!fmt::is_formattable<convertible_to_pointer>::value, "");
+  const auto f = convertible_to_pointer_formattable();
+  EXPECT_EQ(fmt::format("{}", f), "test");
+
+  static_assert(!fmt::is_formattable<void (*)()>::value, "");
+
+  struct s;
+  static_assert(!fmt::is_formattable<int(s::*)>::value, "");
+  static_assert(!fmt::is_formattable<int (s::*)()>::value, "");
+  static_assert(!fmt::is_formattable<unformattable_scoped_enum>::value, "");
+  static_assert(!fmt::is_formattable<unformattable_scoped_enum>::value, "");
+}
+
+TEST(core_test, format) { EXPECT_EQ(fmt::format("{}", 42), "42"); }
+
+TEST(core_test, format_to) {
+  auto s = std::string();
+  fmt::format_to(std::back_inserter(s), "{}", 42);
+  EXPECT_EQ(s, "42");
+}
+
+#ifdef __cpp_lib_byte
+TEST(core_test, format_byte) {
+  EXPECT_EQ(fmt::format("{}", std::byte(42)), "42");
+}
+#endif
+
+struct convertible_to_int {
+  operator int() const { return 42; }
+};
+
+struct convertible_to_cstring {
+  operator const char*() const { return "foo"; }
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<convertible_to_int> {
+  FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+  auto format(convertible_to_int, format_context& ctx) const
+      -> decltype(ctx.out()) {
+    return std::copy_n("foo", 3, ctx.out());
+  }
+};
+
+template <> struct formatter<convertible_to_cstring> {
+  FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+  auto format(convertible_to_cstring, format_context& ctx) const
+      -> decltype(ctx.out()) {
+    return std::copy_n("bar", 3, ctx.out());
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(core_test, formatter_overrides_implicit_conversion) {
+  EXPECT_EQ(fmt::format("{}", convertible_to_int()), "foo");
+  EXPECT_EQ(fmt::format("{}", convertible_to_cstring()), "bar");
+}
+
+// Test that check is not found by ADL.
+template <typename T> void check(T);
+TEST(core_test, adl_check) {
+  EXPECT_EQ(fmt::format("{}", test_struct()), "test");
+}
+
+struct implicitly_convertible_to_string_view {
+  operator fmt::string_view() const { return "foo"; }
+};
+
+TEST(core_test, no_implicit_conversion_to_string_view) {
+  EXPECT_FALSE(
+      fmt::is_formattable<implicitly_convertible_to_string_view>::value);
+}
+
+#ifdef FMT_USE_STRING_VIEW
+struct implicitly_convertible_to_std_string_view {
+  operator std::string_view() const { return "foo"; }
+};
+
+TEST(core_test, no_implicit_conversion_to_std_string_view) {
+  EXPECT_FALSE(
+      fmt::is_formattable<implicitly_convertible_to_std_string_view>::value);
+}
+#endif
+
+// std::is_constructible is broken in MSVC until version 2015.
+#if !FMT_MSC_VERSION || FMT_MSC_VERSION >= 1900
+struct explicitly_convertible_to_string_view {
+  explicit operator fmt::string_view() const { return "foo"; }
+};
+
+TEST(core_test, format_explicitly_convertible_to_string_view) {
+  // Types explicitly convertible to string_view are not formattable by
+  // default because it may introduce ODR violations.
+  static_assert(
+      !fmt::is_formattable<explicitly_convertible_to_string_view>::value, "");
+}
+
+#  ifdef FMT_USE_STRING_VIEW
+struct explicitly_convertible_to_std_string_view {
+  explicit operator std::string_view() const { return "foo"; }
+};
+
+TEST(core_test, format_explicitly_convertible_to_std_string_view) {
+  // Types explicitly convertible to string_view are not formattable by
+  // default because it may introduce ODR violations.
+  static_assert(
+      !fmt::is_formattable<explicitly_convertible_to_std_string_view>::value,
+      "");
+}
+#  endif
+#endif
+
+namespace adl_test {
+template <typename... T> void make_format_args(const T&...) = delete;
+
+struct string : std::string {};
+}  // namespace adl_test
+
+// Test that formatting functions compile when make_format_args is found by ADL.
+TEST(core_test, adl) {
+  // Only check compilation and don't run the code to avoid polluting the output
+  // and since the output is tested elsewhere.
+  if (fmt::detail::const_check(true)) return;
+  auto s = adl_test::string();
+  char buf[10];
+  (void)fmt::format("{}", s);
+  fmt::format_to(buf, "{}", s);
+  fmt::format_to_n(buf, 10, "{}", s);
+  (void)fmt::formatted_size("{}", s);
+  fmt::print("{}", s);
+  fmt::print(stdout, "{}", s);
+}
+
+TEST(core_test, has_const_formatter) {
+  EXPECT_TRUE((fmt::detail::has_const_formatter<const_formattable,
+                                                fmt::format_context>()));
+  EXPECT_FALSE((fmt::detail::has_const_formatter<nonconst_formattable,
+                                                 fmt::format_context>()));
+}
+
+TEST(core_test, format_nonconst) {
+  EXPECT_EQ(fmt::format("{}", nonconst_formattable()), "test");
+}
+
+struct its_a_trap {
+  template <typename T> operator T() const {
+    auto v = T();
+    v.x = 42;
+    return v;
+  }
+};
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<its_a_trap> {
+  FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  auto format(its_a_trap, format_context& ctx) const -> decltype(ctx.out()) {
+    auto s = string_view("42");
+    return std::copy(s.begin(), s.end(), ctx.out());
+  }
+};
+FMT_END_NAMESPACE
+
+TEST(core_test, trappy_conversion) {
+  EXPECT_EQ(fmt::format("{}", its_a_trap()), "42");
+}

test/cuda-test/CMakeLists.txt

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

test/cuda-test/cpp14.cc

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

test/cuda-test/cuda-cpp14.cu

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

test/custom-formatter-test.cc

@@ -1,46 +0,0 @@
-// Formatting library for C++ - custom argument formatter tests
-//
-// Copyright (c) 2012 - present, Victor Zverovich
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-#include "fmt/format.h"
-#include "gtest-extra.h"
-
-// A custom argument formatter that doesn't print `-` for floating-point values
-// rounded to 0.
-class custom_arg_formatter :
-    public fmt::arg_formatter<fmt::back_insert_range<fmt::internal::buffer>> {
- public:
-  typedef fmt::back_insert_range<fmt::internal::buffer> range;
-  typedef fmt::arg_formatter<range> base;
-
-  custom_arg_formatter(fmt::format_context &ctx, fmt::format_specs &s)
-  : base(ctx, s) {}
-
-  using base::operator();
-
-  iterator operator()(double value) {
-    if (round(value * pow(10, spec().precision())) == 0)
-      value = 0;
-    return base::operator()(value);
-  }
-};
-
-std::string custom_vformat(fmt::string_view format_str, fmt::format_args args) {
-  fmt::memory_buffer buffer;
-  // Pass custom argument formatter as a template arg to vwrite.
-  fmt::vformat_to<custom_arg_formatter>(buffer, format_str, args);
-  return std::string(buffer.data(), buffer.size());
-}
-
-template <typename... Args>
-std::string custom_format(const char *format_str, const Args & ... args) {
-  auto va = fmt::make_format_args(args...);
-  return custom_vformat(format_str, va);
-}
-
-TEST(CustomFormatterTest, Format) {
-  EXPECT_EQ("0.00", custom_format("{:.2f}", -.00001));
-}

test/detect-stdfs.cc

@@ -0,0 +1,18 @@
+// Formatting library for C++ - tests of formatters for standard library types
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include <exception>  // _GLIBCXX_RELEASE & _LIBCPP_VERSION
+
+#if defined(_GLIBCXX_RELEASE) && _GLIBCXX_RELEASE == 8
+#  error libfound "stdc++fs"
+#elif !defined(__apple_build_version__) && defined(_LIBCPP_VERSION) && \
+    _LIBCPP_VERSION >= 7000 && _LIBCPP_VERSION < 9000
+#  error libfound "c++fs"
+#else
+// none if std::filesystem does not require additional libraries
+#  error libfound ""
+#endif

test/enforce-checks-test.cc

@@ -0,0 +1,65 @@
+// 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>
+
+#define I 42  // simulate https://en.cppreference.com/w/c/numeric/complex/I
+#include "fmt/chrono.h"
+#include "fmt/color.h"
+#include "fmt/format.h"
+#include "fmt/ostream.h"
+#include "fmt/ranges.h"
+#include "fmt/xchar.h"
+#undef I
+
+// 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

@@ -1,15 +1,17 @@
-cmake_minimum_required(VERSION 2.8.12)
+cmake_minimum_required(VERSION 3.8...3.25)
 
 project(fmt-test)
 
 find_package(FMT REQUIRED)
 
 add_executable(library-test main.cc)
-target_compile_options(library-test PUBLIC ${CPP14_FLAG})
 target_link_libraries(library-test fmt::fmt)
+target_compile_options(library-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
+target_include_directories(library-test PUBLIC SYSTEM .)
 
 if (TARGET fmt::fmt-header-only)
   add_executable(header-only-test main.cc)
-  target_compile_options(header-only-test PUBLIC ${CPP14_FLAG})
   target_link_libraries(header-only-test fmt::fmt-header-only)
+  target_compile_options(header-only-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
+  target_include_directories(header-only-test PUBLIC SYSTEM .)
 endif ()

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-impl-test.cc

@@ -5,115 +5,472 @@
 //
 // 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 "../src/format.cc"
-#include "fmt/printf.h"
-
 #include <algorithm>
 #include <cstring>
 
+// clang-format off
+#include "test-assert.h"
+// clang-format on
+
+#include "fmt/format.h"
 #include "gmock/gmock.h"
-#include "gtest-extra.h"
 #include "util.h"
 
-#undef min
-#undef max
+using fmt::detail::bigint;
+using fmt::detail::fp;
+using fmt::detail::max_value;
 
-template <typename T>
-struct ValueExtractor: fmt::internal::function<T> {
-  T operator()(T value) {
-    return value;
-  }
+static_assert(!std::is_copy_constructible<bigint>::value, "");
+static_assert(!std::is_copy_assignable<bigint>::value, "");
 
-  template <typename U>
-  T operator()(U) {
-    throw std::runtime_error(fmt::format("invalid type {}", typeid(U).name()));
-    return T();
-  }
-};
-
-TEST(FormatTest, ArgConverter) {
-  long long value = std::numeric_limits<long long>::max();
-  auto arg = fmt::internal::make_arg<fmt::format_context>(value);
-  visit(fmt::internal::arg_converter<long long, fmt::format_context>(arg, 'd'),
-        arg);
-  EXPECT_EQ(value, visit(ValueExtractor<long long>(), arg));
+TEST(bigint_test, construct) {
+  EXPECT_EQ(fmt::to_string(bigint()), "");
+  EXPECT_EQ(fmt::to_string(bigint(0x42)), "42");
+  EXPECT_EQ(fmt::to_string(bigint(0x123456789abcedf0)), "123456789abcedf0");
 }
 
-TEST(FormatTest, FormatNegativeNaN) {
-  double nan = std::numeric_limits<double>::quiet_NaN();
-  if (fmt::internal::fputil::isnegative(-nan))
-    EXPECT_EQ("-nan", fmt::format("{}", -nan));
-  else
-    fmt::print("Warning: compiler doesn't handle negative NaN correctly");
+TEST(bigint_test, compare) {
+  bigint n1(42);
+  bigint n2(42);
+  EXPECT_EQ(compare(n1, n2), 0);
+  n2 <<= 32;
+  EXPECT_LT(compare(n1, n2), 0);
+  bigint n3(43);
+  EXPECT_LT(compare(n1, n3), 0);
+  EXPECT_GT(compare(n3, n1), 0);
+  bigint n4(42 * 0x100000001);
+  EXPECT_LT(compare(n2, n4), 0);
+  EXPECT_GT(compare(n4, n2), 0);
 }
 
-TEST(FormatTest, StrError) {
-  char *message = 0;
-  char buffer[BUFFER_SIZE];
-  EXPECT_ASSERT(fmt::safe_strerror(EDOM, message = 0, 0), "invalid buffer");
-  EXPECT_ASSERT(fmt::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::safe_strerror(error_code, message = buffer, BUFFER_SIZE);
-  EXPECT_EQ(0, result);
-  std::size_t message_size = std::strlen(message);
-  EXPECT_GE(BUFFER_SIZE - 1u, message_size);
-  EXPECT_EQ(get_system_error(error_code), message);
-
-  // safe_strerror never uses buffer on MinGW.
-#ifndef __MINGW32__
-  result = fmt::safe_strerror(error_code, message = buffer, message_size);
-  EXPECT_EQ(ERANGE, result);
-  result = fmt::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(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);
+  EXPECT_GT(add_compare(bigint(1) <<= 32, bigint(0), bigint(0xffffffff)), 0);
+  EXPECT_GT(add_compare(bigint(0), bigint(1) <<= 32, bigint(0xffffffff)), 0);
+  EXPECT_GT(add_compare(bigint(42), bigint(1), bigint(42)), 0);
+  EXPECT_GT(add_compare(bigint(0xffffffff), bigint(1), bigint(0xffffffff)), 0);
+  EXPECT_LT(add_compare(bigint(10), bigint(10), bigint(22)), 0);
+  EXPECT_LT(add_compare(bigint(0x100000010), bigint(0x100000010),
+                        bigint(0x300000010)),
+            0);
+  EXPECT_GT(add_compare(bigint(0x1ffffffff), bigint(0x100000002),
+                        bigint(0x300000000)),
+            0);
+  EXPECT_EQ(add_compare(bigint(0x1ffffffff), bigint(0x100000002),
+                        bigint(0x300000001)),
+            0);
+  EXPECT_LT(add_compare(bigint(0x1ffffffff), bigint(0x100000002),
+                        bigint(0x300000002)),
+            0);
+  EXPECT_LT(add_compare(bigint(0x1ffffffff), bigint(0x100000002),
+                        bigint(0x300000003)),
+            0);
 }
 
-TEST(FormatTest, FormatErrorCode) {
+TEST(bigint_test, shift_left) {
+  bigint n(0x42);
+  n <<= 0;
+  EXPECT_EQ(fmt::to_string(n), "42");
+  n <<= 1;
+  EXPECT_EQ(fmt::to_string(n), "84");
+  n <<= 25;
+  EXPECT_EQ(fmt::to_string(n), "108000000");
+}
+
+TEST(bigint_test, multiply) {
+  bigint n(0x42);
+  EXPECT_THROW(n *= 0, assertion_failure);
+  n *= 1;
+  EXPECT_EQ(fmt::to_string(n), "42");
+
+  n *= 2;
+  EXPECT_EQ(fmt::to_string(n), "84");
+  n *= 0x12345678;
+  EXPECT_EQ(fmt::to_string(n), "962fc95e0");
+
+  bigint bigmax(max_value<uint32_t>());
+  bigmax *= max_value<uint32_t>();
+  EXPECT_EQ(fmt::to_string(bigmax), "fffffffe00000001");
+
+  const auto max64 = max_value<uint64_t>();
+  bigmax = max64;
+  bigmax *= max64;
+  EXPECT_EQ(fmt::to_string(bigmax), "fffffffffffffffe0000000000000001");
+
+  const auto max128 = (fmt::detail::uint128_t(max64) << 64) | max64;
+  bigmax = max128;
+  bigmax *= max128;
+  EXPECT_EQ(fmt::to_string(bigmax),
+            "fffffffffffffffffffffffffffffffe00000000000000000000000000000001");
+}
+
+TEST(bigint_test, square) {
+  bigint n0(0);
+  n0.square();
+  EXPECT_EQ(fmt::to_string(n0), "0");
+  bigint n1(0x100);
+  n1.square();
+  EXPECT_EQ(fmt::to_string(n1), "10000");
+  bigint n2(0xfffffffff);
+  n2.square();
+  EXPECT_EQ(fmt::to_string(n2), "ffffffffe000000001");
+  bigint n3(max_value<uint64_t>());
+  n3.square();
+  EXPECT_EQ(fmt::to_string(n3), "fffffffffffffffe0000000000000001");
+  bigint n4;
+  n4.assign_pow10(10);
+  EXPECT_EQ(fmt::to_string(n4), "2540be400");
+}
+
+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(bigint_test, divmod_assign_self) {
+  bigint n(100);
+  EXPECT_THROW(n.divmod_assign(n), assertion_failure);
+}
+
+TEST(bigint_test, divmod_assign_unaligned) {
+  // (42 << 340) / pow(10, 100):
+  bigint n1(42);
+  n1 <<= 340;
+  bigint n2;
+  n2.assign_pow10(100);
+  int result = n1.divmod_assign(n2);
+  EXPECT_EQ(result, 9406);
+  EXPECT_EQ(fmt::to_string(n1),
+            "10f8353019583bfc29ffc8f564e1b9f9d819dbb4cf783e4507eca1539220p96");
+}
+
+TEST(bigint_test, divmod_assign) {
+  // 100 / 10:
+  bigint n1(100);
+  int result = n1.divmod_assign(bigint(10));
+  EXPECT_EQ(result, 10);
+  EXPECT_EQ(fmt::to_string(n1), "0");
+  // pow(10, 100) / (42 << 320):
+  n1.assign_pow10(100);
+  result = n1.divmod_assign(bigint(42) <<= 320);
+  EXPECT_EQ(result, 111);
+  EXPECT_EQ(fmt::to_string(n1),
+            "13ad2594c37ceb0b2784c4ce0bf38ace408e211a7caab24308a82e8f10p96");
+  // 42 / 100:
+  bigint n2(42);
+  n1.assign_pow10(2);
+  result = n2.divmod_assign(n1);
+  EXPECT_EQ(result, 0);
+  EXPECT_EQ(fmt::to_string(n2), "2a");
+}
+
+template <bool is_iec559> void run_double_tests() {
+  fmt::print("warning: double is not IEC559, skipping FP tests\n");
+}
+
+template <> void run_double_tests<true>() {
+  // Construct from double.
+  EXPECT_EQ(fp(1.23), fp(0x13ae147ae147aeu, -52));
+}
+
+TEST(fp_test, double_tests) {
+  run_double_tests<std::numeric_limits<double>::is_iec559>();
+}
+
+TEST(fp_test, normalize) {
+  const auto v = fp(0xbeef, 42);
+  auto normalized = normalize(v);
+  EXPECT_EQ(normalized.f, 0xbeef000000000000);
+  EXPECT_EQ(normalized.e, -6);
+}
+
+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);
+  v = fp(123ULL << 32, 4) * fp(567ULL << 31, 8);
+  EXPECT_EQ(v.f, (123 * 567 + 1u) / 2);
+  EXPECT_EQ(v.e, 4 + 8 + 64);
+}
+
+TEST(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(std::numeric_limits<float>::min_exponent -
+                           fmt::detail::num_significand_bits<float>() - 1));
+  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(
+                    std::numeric_limits<double>::min_exponent -
+                    2 * fmt::detail::num_significand_bits<double>() - 1));
+}
+
+TEST(format_impl_test, format_error_code) {
   std::string msg = "error 42", sep = ": ";
   {
-    fmt::memory_buffer buffer;
-    format_to(buffer, "garbage");
-    fmt::format_error_code(buffer, 42, "test");
-    EXPECT_EQ("test: " + msg, to_string(buffer));
+    auto buffer = fmt::memory_buffer();
+    fmt::format_to(fmt::appender(buffer), "garbage");
+    fmt::detail::format_error_code(buffer, 42, "test");
+    EXPECT_EQ(to_string(buffer), "test: " + msg);
   }
   {
-    fmt::memory_buffer buffer;
-    std::string prefix(
-        fmt::inline_buffer_size - msg.size() - sep.size() + 1, 'x');
-    fmt::format_error_code(buffer, 42, prefix);
+    auto buffer = fmt::memory_buffer();
+    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));
   }
   int codes[] = {42, -1};
-  for (std::size_t i = 0, n = sizeof(codes) / sizeof(*codes); i < n; ++i) {
+  for (size_t i = 0, n = sizeof(codes) / sizeof(*codes); i < n; ++i) {
     // Test maximum buffer size.
     msg = fmt::format("error {}", codes[i]);
     fmt::memory_buffer buffer;
-    std::string prefix(
-        fmt::inline_buffer_size - msg.size() - sep.size(), 'x');
-    fmt::format_error_code(buffer, codes[i], prefix);
+    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));
-    std::size_t size = fmt::inline_buffer_size;
+    size_t size = fmt::inline_buffer_size;
     EXPECT_EQ(size, buffer.size());
     buffer.resize(0);
     // Test with a message that doesn't fit into the buffer.
     prefix += 'x';
-    fmt::format_error_code(buffer, codes[i], prefix);
-    EXPECT_EQ(msg, to_string(buffer));
+    fmt::detail::format_error_code(buffer, codes[i], prefix);
+    EXPECT_EQ(to_string(buffer), msg);
   }
 }
+
+// Tests fmt::detail::count_digits for integer type Int.
+template <typename Int> void test_count_digits() {
+  for (Int i = 0; i < 10; ++i) EXPECT_EQ(1u, fmt::detail::count_digits(i));
+  for (Int i = 1, n = 1, end = max_value<Int>() / 10; n <= end; ++i) {
+    n *= 10;
+    EXPECT_EQ(fmt::detail::count_digits(n - 1), i);
+    EXPECT_EQ(fmt::detail::count_digits(n), i + 1);
+  }
+}
+
+TEST(format_impl_test, count_digits) {
+  test_count_digits<uint32_t>();
+  test_count_digits<uint64_t>();
+}
+
+TEST(format_impl_test, countl_zero) {
+  constexpr auto num_bits = fmt::detail::num_bits<uint32_t>();
+  uint32_t n = 1u;
+  for (int i = 1; i < num_bits - 1; i++) {
+    n <<= 1;
+    EXPECT_EQ(fmt::detail::countl_zero(n - 1), num_bits - i);
+    EXPECT_EQ(fmt::detail::countl_zero(n), num_bits - i - 1);
+  }
+}
+
+#if FMT_USE_FLOAT128
+TEST(format_impl_test, write_float128) {
+  auto s = std::string();
+  fmt::detail::write<char>(std::back_inserter(s), __float128(42));
+  EXPECT_EQ(s, "42");
+}
+#endif
+
+struct double_double {
+  double a;
+  double b;
+
+  explicit constexpr double_double(double a_val = 0, double b_val = 0)
+      : a(a_val), b(b_val) {}
+
+  operator double() const { return a + b; }
+  auto operator-() const -> double_double { return double_double(-a, -b); }
+};
+
+auto format_as(double_double d) -> double { return d; }
+
+bool operator>=(const double_double& lhs, const double_double& rhs) {
+  return lhs.a + lhs.b >= rhs.a + rhs.b;
+}
+
+struct slow_float {
+  float value;
+
+  explicit constexpr slow_float(float val = 0) : value(val) {}
+  operator float() const { return value; }
+  auto operator-() const -> slow_float { return slow_float(-value); }
+};
+
+auto format_as(slow_float f) -> float { return f; }
+
+namespace std {
+template <> struct is_floating_point<double_double> : std::true_type {};
+template <> struct numeric_limits<double_double> {
+  // is_iec559 is true for double-double in libstdc++.
+  static constexpr bool is_iec559 = true;
+  static constexpr int digits = 106;
+};
+
+template <> struct is_floating_point<slow_float> : std::true_type {};
+template <> struct numeric_limits<slow_float> : numeric_limits<float> {};
+}  // namespace std
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+template <> struct is_fast_float<slow_float> : std::false_type {};
+namespace dragonbox {
+template <> struct float_info<slow_float> {
+  using carrier_uint = uint32_t;
+  static const int exponent_bits = 8;
+};
+}  // namespace dragonbox
+}  // namespace detail
+FMT_END_NAMESPACE
+
+TEST(format_impl_test, write_double_double) {
+  auto s = std::string();
+  fmt::detail::write<char>(std::back_inserter(s), double_double(42), {});
+  // Specializing is_floating_point is broken in MSVC.
+  if (!FMT_MSC_VERSION) EXPECT_EQ(s, "42");
+}
+
+TEST(format_impl_test, write_dragon_even) {
+  auto s = std::string();
+  fmt::detail::write<char>(std::back_inserter(s), slow_float(33554450.0f), {});
+  // Specializing is_floating_point is broken in MSVC.
+  if (!FMT_MSC_VERSION) EXPECT_EQ(s, "33554450");
+}
+
+#if defined(_WIN32) && !defined(FMT_WINDOWS_NO_WCHAR)
+#  include <windows.h>
+
+TEST(format_impl_test, write_console_signature) {
+  decltype(::WriteConsoleW)* p = fmt::detail::WriteConsoleW;
+  (void)p;
+}
+#endif
+
+// A public domain branchless UTF-8 decoder by Christopher Wellons:
+// https://github.com/skeeto/branchless-utf8
+constexpr bool unicode_is_surrogate(uint32_t c) {
+  return c >= 0xD800U && c <= 0xDFFFU;
+}
+
+FMT_CONSTEXPR char* utf8_encode(char* s, uint32_t c) {
+  if (c >= (1UL << 16)) {
+    s[0] = static_cast<char>(0xf0 | (c >> 18));
+    s[1] = static_cast<char>(0x80 | ((c >> 12) & 0x3f));
+    s[2] = static_cast<char>(0x80 | ((c >> 6) & 0x3f));
+    s[3] = static_cast<char>(0x80 | ((c >> 0) & 0x3f));
+    return s + 4;
+  } else if (c >= (1UL << 11)) {
+    s[0] = static_cast<char>(0xe0 | (c >> 12));
+    s[1] = static_cast<char>(0x80 | ((c >> 6) & 0x3f));
+    s[2] = static_cast<char>(0x80 | ((c >> 0) & 0x3f));
+    return s + 3;
+  } else if (c >= (1UL << 7)) {
+    s[0] = static_cast<char>(0xc0 | (c >> 6));
+    s[1] = static_cast<char>(0x80 | ((c >> 0) & 0x3f));
+    return s + 2;
+  } else {
+    s[0] = static_cast<char>(c);
+    return s + 1;
+  }
+}
+
+// Make sure it can decode every character
+TEST(format_impl_test, utf8_decode_decode_all) {
+  for (uint32_t i = 0; i < 0x10ffff; i++) {
+    if (!unicode_is_surrogate(i)) {
+      int e;
+      uint32_t c;
+      char buf[8] = {0};
+      char* end = utf8_encode(buf, i);
+      const char* res = fmt::detail::utf8_decode(buf, &c, &e);
+      EXPECT_EQ(end, res);
+      EXPECT_EQ(c, i);
+      EXPECT_EQ(e, 0);
+    }
+  }
+}
+
+// Reject everything outside of U+0000..U+10FFFF
+TEST(format_impl_test, utf8_decode_out_of_range) {
+  for (uint32_t i = 0x110000; i < 0x1fffff; i++) {
+    int e;
+    uint32_t c;
+    char buf[8] = {0};
+    utf8_encode(buf, i);
+    const char* end = fmt::detail::utf8_decode(buf, &c, &e);
+    EXPECT_NE(e, 0);
+    EXPECT_EQ(end - buf, 4);
+  }
+}
+
+// Does it reject all surrogate halves?
+TEST(format_impl_test, utf8_decode_surrogate_halves) {
+  for (uint32_t i = 0xd800; i <= 0xdfff; i++) {
+    int e;
+    uint32_t c;
+    char buf[8] = {0};
+    utf8_encode(buf, i);
+    fmt::detail::utf8_decode(buf, &c, &e);
+    EXPECT_NE(e, 0);
+  }
+}
+
+// How about non-canonical encodings?
+TEST(format_impl_test, utf8_decode_non_canonical_encodings) {
+  int e;
+  uint32_t c;
+  const char* end;
+
+  char buf2[8] = {char(0xc0), char(0xA4)};
+  end = fmt::detail::utf8_decode(buf2, &c, &e);
+  EXPECT_NE(e, 0);           // non-canonical len 2
+  EXPECT_EQ(end, buf2 + 2);  // non-canonical recover 2
+
+  char buf3[8] = {char(0xe0), char(0x80), char(0xA4)};
+  end = fmt::detail::utf8_decode(buf3, &c, &e);
+  EXPECT_NE(e, 0);           // non-canonical len 3
+  EXPECT_EQ(end, buf3 + 3);  // non-canonical recover 3
+
+  char buf4[8] = {char(0xf0), char(0x80), char(0x80), char(0xA4)};
+  end = fmt::detail::utf8_decode(buf4, &c, &e);
+  EXPECT_NE(e, 0);           // non-canonical encoding len 4
+  EXPECT_EQ(end, buf4 + 4);  // non-canonical recover 4
+}
+
+// Let's try some bogus byte sequences
+TEST(format_impl_test, utf8_decode_bogus_byte_sequences) {
+  int e;
+  uint32_t c;
+
+  // Invalid first byte
+  char buf0[4] = {char(0xff)};
+  auto len = fmt::detail::utf8_decode(buf0, &c, &e) - buf0;
+  EXPECT_NE(e, 0);    // "bogus [ff] 0x%02x U+%04lx", e, (unsigned long)c);
+  EXPECT_EQ(len, 1);  // "bogus [ff] recovery %d", len);
+
+  // Invalid first byte
+  char buf1[4] = {char(0x80)};
+  len = fmt::detail::utf8_decode(buf1, &c, &e) - buf1;
+  EXPECT_NE(e, 0);    // "bogus [80] 0x%02x U+%04lx", e, (unsigned long)c);
+  EXPECT_EQ(len, 1);  // "bogus [80] recovery %d", len);
+
+  // Looks like a two-byte sequence but second byte is wrong
+  char buf2[4] = {char(0xc0), char(0x0a)};
+  len = fmt::detail::utf8_decode(buf2, &c, &e) - buf2;
+  EXPECT_NE(e, 0);    // "bogus [c0 0a] 0x%02x U+%04lx", e, (unsigned long)c
+  EXPECT_EQ(len, 2);  // "bogus [c0 0a] recovery %d", len);
+}
+
+TEST(format_impl_test, to_utf8) {
+  auto s = std::string("ёжик");
+  auto u = fmt::detail::to_utf8<wchar_t>(L"\x0451\x0436\x0438\x043A");
+  EXPECT_EQ(s, u.str());
+  EXPECT_EQ(s.size(), u.size());
+}