fmt 11.0.0

[BrewTestBot]

Created by brew bump

---

Created with brew bump-formula-pr.

release notes

- Added `fmt/base.h` which provides a subset of the API with minimal include dependencies and enough functionality to replace all uses of the `printf` family of functions. This brings the compile time of code using {fmt} much closer to the equivalent `printf` code as shown on the following benchmark that compiles 100 source files:



Method
Compile Time (s)




printf
1.6


IOStreams
25.9


fmt 10.x
19.0


fmt 11.0
4.8


tinyformat
29.1


Boost Format
55.0



This gives almost 4x improvement in build speed compared to version 10. Note that the benchmark is purely formatting code and includes. In real projects the difference from printf will be smaller partly because common standard headers will be included in almost any translation unit (TU) anyway. In particular, in every case except printf above ~1s is spent in total on including <type_traits> in all TUs.


Optimized includes in other headers such as fmt/format.h which is now roughly equivalent to the old fmt/core.h in terms of build speed.


Migrated the documentation at https://fmt.dev/ from Sphinx to MkDocs.


Improved C++20 module support (Use native c++ module support from CMake fmtlib/fmt#3990, Use native c++ module support from CMake fmtlib/fmt#3991, Build issue with WinLibs GCC on Windows after C++20 modules update fmtlib/fmt#3993, Fix missing includes in fmt.cc fmtlib/fmt#3994, Fix build with FMT_MODULE=OFF fmtlib/fmt#3997, Fix FMT_INSTALL with FMT_MODULE fmtlib/fmt#3998, Don't add os.cc to sources with FMT_MODULE fmtlib/fmt#4004, Check if .cc exists in fmt.cc fmtlib/fmt#4005, Guard more system headers by FMT_MODULE fmtlib/fmt#4006, Only install FILE_SET when needed fmtlib/fmt#4013, Defines are still needed for FMT_MODULE as well fmtlib/fmt#4027, Module purview can only contain direct preprocessor code fmtlib/fmt#4029). In particular, native CMake support for modules is now used if available. Thanks @yujincheng08 and @matt77hias.


Added an option to replace standard includes with import std enabled via the FMT_IMPORT_STD macro (MSVC errors when importing both fmt and std modules fmtlib/fmt#3921, Added FMT_IMPORT_STD feature macro fmtlib/fmt#3928). Thanks @matt77hias.


Exported fmt::range_format, fmt::range_format_kind and fmt::compiled_string from the fmt module (Added FMT_EXPORT to fmt::range_format and fmt::range_format_kind fmtlib/fmt#3970, Export compiled_string so that user can customize one fmtlib/fmt#3999). Thanks @matt77hias and @yujincheng08.


Improved integration with stdio in fmt::print, enabling direct writes into a C stream buffer in common cases. This may give significant performance improvements ranging from tens of percent to 2x and eliminates dynamic memory allocations on the buffer level. It is currently enabled for built-in and string types with wider availability coming up in future releases.
For example, it gives ~24% improvement on a simple benchmark compiled with Apple clang version 15.0.0 (clang-1500.1.0.2.5) and run on macOS 14.2.1:
-------------------------------------------------------
Benchmark             Time             CPU   Iterations
-------------------------------------------------------
printf             81.8 ns         81.5 ns      8496899
fmt::print (10.x)  63.8 ns         61.9 ns     11524151
fmt::print (11.0)  51.3 ns         51.0 ns     13846580



Improved safety of fmt::format_to when writing to an array (🛠 Add basic array safety functions and backwards-compatible result type fmtlib/fmt#3805). For example (godbolt):
auto volkswagen = char[4];
auto result = fmt::format_to(volkswagen, "elephant");
no longer results in a buffer overflow. Instead the output will be truncated and you can get the end iterator and whether truncation occurred from the result object. Thanks @ThePhD.


Enabled Unicode support by default in MSVC, bringing it on par with other compilers and making it unnecessary for users to enable it explicitly. Most of {fmt} is encoding-agnostic but this prevents mojibake in places where encoding matters such as path formatting and terminal output. You can control the Unicode support via the CMake FMT_UNICODE option. Note that some {fmt} packages such as the one in vcpkg have already been compiled with Unicode enabled.


Added a formatter for std::expected (added formatter for std::expected fmtlib/fmt#3834). Thanks @dominicpoeschko.


Added a formatter for std::complex (flexible std::complex formatter fmtlib/fmt#1467, Add support for std::complex fmtlib/fmt#3886, Add std::complex formatter fmtlib/fmt#3892, Improve std::complex formatter to be compatible with P2197R0 fmtlib/fmt#3900). Thanks @phprus.


Added a formatter for std::type_info (Added std::type_info formatter fmtlib/fmt#3978). Thanks @matt77hias.


Specialized formatter for std::basic_string types with custom traits and allocators (Formatting for strings with custom allocators fails to compile fmtlib/fmt#3938, Specialize formatter for all std::basic_string types fmtlib/fmt#3943). Thanks @dieram3.


Added formatters for std::chrono::day, std::chrono::month, std::chrono::year and std::chrono::year_month_day (Green Day Support fmtlib/fmt#3758, Add support for std::chrono::year_month_day fmtlib/fmt#3772, Implemented fmt::day, fmt::month, fmt::year and related unit tests fmtlib/fmt#3906, implement year_month_day fmtlib/fmt#3913). For example:
#include <fmt/chrono.h>
#include <fmt/color.h>

int main() {
  fmt::print(fg(fmt::color::green), "{}\n", std::chrono::day(7));
}
prints a green day:

Thanks @zivshek.


Fixed handling of precision in %S (%S ignores precision for chrono durations where the decimal part should have been only zeros fmtlib/fmt#3794, Fix %S formatting for chrono durations with leading zeroes  fmtlib/fmt#3814). Thanks @js324.


Added support for the - specifier (glibc strftime extension) to day of the month (%d) and week of the year (%W, %U, %V) specifiers (Add glibc ext for day of month and week of year fmtlib/fmt#3976). Thanks @ZaheenJ.


Fixed the scope of the - extension in chrono formatting so that it doesn't apply to subsequent specifiers (chrono glibc '-' ext applies to following components within a spec fmtlib/fmt#3811, Fix scope for glibc ext for sec, min, and hour fmtlib/fmt#3812). Thanks @phprus.


Improved handling of time_point::min() (fmt chrono fails for clock minimum value fmtlib/fmt#3282).


Added support for character range formatting (support C++23 character range formatting fmtlib/fmt#3857, Support character range formatting  fmtlib/fmt#3863). Thanks @js324.


Added string and debug_string range formatters (Added range_format::string formatter fmtlib/fmt#3973, Added missing std::declval for non-default-constructible types fmtlib/fmt#4024). Thanks @matt77hias.


Enabled ADL for begin and end in fmt::join (join does not use ADL on begin/end of its ranges fmtlib/fmt#3813, Consider ADL begin() and end() when joining ranges fmtlib/fmt#3824). Thanks @bbolli.


Made contiguous iterator optimizations apply to std::basic_string iterators (Add fmt::is_contiguous<std::basic_string<Char, Traits, Allocator>> fmtlib/fmt#3798). Thanks @phprus.


Added support for ranges with mutable begin and end (format_as fails when called with certain std::views fmtlib/fmt#3752, Fix formatting of ranges with lvalue-qualified, non-const begin() and end() fmtlib/fmt#3800, Fix format_as for non-const begin/end views fmtlib/fmt#3955). Thanks @tcbrindle and @Arghnews.


Added support for move-only iterators to fmt::join (fmt::join doesn't handle move-only iterators fmtlib/fmt#3802, Fix fmt::join for views with input iterators fmtlib/fmt#3946). Thanks @Arghnews.


Moved range and iterator overloads of fmt::join to fmt/ranges.h, next to other overloads.


Fixed handling of types with begin returning void such as Eigen matrices (fmt/ranges.h incompatible with Eigen 3.4 fmtlib/fmt#3839, Check range_begin is dereferenceable fmtlib/fmt#3964). Thanks @Arghnews.


Added an fmt::formattable concept (Added formattable concept fmtlib/fmt#3974). Thanks @matt77hias.


Added support for __float128 (Add support for __float128 or std::float128_t fmtlib/fmt#3494).


Fixed rounding issues when formatting long double with fixed precision (Erroneous fixed-precision formatting for long double fmtlib/fmt#3539).


Made fmt::isnan not trigger floating-point exception for NaN values (fmt::isnan triggers floating-point exception for NaN values fmtlib/fmt#3948, Fix isnan so it doesn't cause FP errors fmtlib/fmt#3951). Thanks @alexdewar.


Removed dependency on <memory> for std::allocator_traits when possible (Use std::allocator_traits fmtlib/fmt#3804). Thanks @phprus.


Enabled compile-time checks in formatting functions that take text colors and styles.


Deprecated wide stream overloads of fmt::print that take text styles.


Made format string compilation work with clang 12 and later despite only partial non-type template parameter support (Failed to detect trunk clang to support pre-compiled format fmtlib/fmt#4000, Also allow compiled format for clang >= 12 fmtlib/fmt#4001). Thanks @yujincheng08.


Made fmt::iterator_buffer's move constructor noexcept (Mark iterator_buffer move constructors as noexcept. fmtlib/fmt#3808). Thanks @waywardmonkeys.


Started enforcing that formatter::format is const for compatibility with std::format (LWG 3636 fmtlib/fmt#3447).


Added fmt::basic_format_arg::visit and deprecated fmt::visit_format_arg.


Made fmt::basic_string_view not constructible from nullptr for consistency with std::string_view in C++23 (C++23 compatibility: basic_string_view cannot be constructed from nullptr fmtlib/fmt#3846). Thanks @dalle.


Fixed fmt::group_digits for negative integers (group_digitsdoes not work with negative integers fmtlib/fmt#3891, Fix group_digits for negative integers fmtlib/fmt#3901). Thanks @phprus.


Fixed handling of negative ids in fmt::basic_format_args::get (Fix CodeQL alert fmtlib/fmt#3945). Thanks @marlenecota.


Improved named argument validation (The vformat & vprint functions produce incorrect output when mixing named and positional arguments. fmtlib/fmt#3817).


Disabled copy construction/assignment for fmt::format_arg_store and fixed moved construction (Fix UB in format_arg_store implementation. fmtlib/fmt#3833). Thanks @ivafanas.


Worked around a locale issue in RHEL/devtoolset (chrono locale format code has some bug when using RHEL gcc on CentOS 7.6 to compile fmtlib/fmt#3858, Fix chrono locale format bug for RHEL gcc fmtlib/fmt#3859). Thanks @g199209.


Added RTTI detection for MSVC (Don't always enable typeid usage under MSVC fmtlib/fmt#3821, Update checks for dynamic_cast usage when compiled with no rtti fmtlib/fmt#3963). Thanks @edo9300.


Migrated the documentation from Sphinx to MkDocs.


Improved documentation and README (Documentation for println functions is missing fmtlib/fmt#3775, Update README.md fmtlib/fmt#3784, Unexpected behaviour of a format string with alignment and zero fmtlib/fmt#3788, Update documentation fmtlib/fmt#3789, Update fmt/std.h section fmtlib/fmt#3793, Documentation: API example for user-defined formatter doesn't compile fmtlib/fmt#3818, Fix custom formatter example fmtlib/fmt#3820, doc: fix the chrono %C example value fmtlib/fmt#3822, Fix some typos. fmtlib/fmt#3843, Fix relative path for cmake in usage doc fmtlib/fmt#3890, Custom formatter example from the documentation fails to compile fmtlib/fmt#3894, Fix invalid fmt::formatter<>::format return type fmtlib/fmt#3895, Range formatting documentation  fmtlib/fmt#3905, Question: what's the difference between string-like formatters and where are they defined? fmtlib/fmt#3942, README.md: update to remove "not yet release" remarks on clang-tidy fmtlib/fmt#4008). Thanks @zencatalyst, WolleTD, @tupaschoal, @Dobiasd, @frank-weinberg, @bbolli, @phprus, @waywardmonkeys, @js324 and @tchaikov.


Improved CI and tests ([qtest-parallel testing] C++ exception with description "cannot open file test-file: No such file or directory" thrown in the test body. fmtlib/fmt#3878, Update os-test.cc fmtlib/fmt#3883, Unstable test format_test.line_buffering fmtlib/fmt#3897, Reintroduce GCC-11 C++20 into CI fmtlib/fmt#3979, ci: Remove macos-11 runners, add macos-14 fmtlib/fmt#3980, github: update lint.yml to post details on formatting issue fmtlib/fmt#3988, Fix build docs on forks fmtlib/fmt#4010, Update msys2/setup-msys2 to v2.23.0 fmtlib/fmt#4012, Change actions/github-script from e69ef54 -> 60a0d83 fmtlib/fmt#4038). Thanks @vgorrX, @waywardmonkeys, @tchaikov and @phprus.


Fixed buffer overflow when using format string compilation with debug format and std::back_insert_iterator (Incorrect output and segfault with std::optional<std::string> and FMT_COMPILE fmtlib/fmt#3795, Fix buffer overflow if output iterator is std::back_insert_iterator and value is escaped (debug format) fmtlib/fmt#3797). Thanks @phprus.


Improved Bazel support (Extend Bazel build support to bzlmod fmtlib/fmt#3792, Bazel support: Switch to globbing to collect header files fmtlib/fmt#3801, Bazel support: Add utf-8 to Windows build fmtlib/fmt#3962, Bazel support: Add missing platform dependency fmtlib/fmt#3965). Thanks @Vertexwahn.


Improved/fixed the CMake config (fmt.cc includes os.cc regardless of the FMT_OS option. fmtlib/fmt#3777, Fix FMT_OS definition fmtlib/fmt#3783, core.h does not exist. fmtlib/fmt#3847, Make CMake version message less confusing fmtlib/fmt#3907). Thanks @phprus and @xTachyon.


Fixed various warnings and compilation issues (Specializing std::pair formatter leads to compile failures fmtlib/fmt#3685, Different visibility warning fmtlib/fmt#3769, Missing formatter leads to compiler crash for clang 15 or below fmtlib/fmt#3796, GCC9 issue: static_assert(std::is_same<uint64_or_128_t<UInt>, UInt>::value, ""); fmtlib/fmt#3803, Fix conversion warning in filesystem::path formatter fmtlib/fmt#3806, Fix MSVC warning: "The contents of <bit> are available only with C++20 or later." fmtlib/fmt#3807, nested_formatter compilation errors fmtlib/fmt#3809, Workaround for gcc 6 fmtlib/fmt#3810, g++-14 warning on self-comparison fmtlib/fmt#3830, Really fix MSVC warning about <bit> only being available in C++20. fmtlib/fmt#3832, FMT_STATIC_THOUSANDS_SEPARATOR broken in 10.0.0 fmtlib/fmt#3835, Fix typo in typename. containter_type -> container_type. fmtlib/fmt#3844, fmt/std.h happy with c++20, unhappy with c++23 fmtlib/fmt#3854, std.h c++23 build fix fmtlib/fmt#3856, Fix warning C4365 emitted from printf.h fmtlib/fmt#3865, Fix warning C4702 emitted from format.h (MSVC) fmtlib/fmt#3866, Guard against usage of _isatty when header was not included fmtlib/fmt#3880, Does not build on OpenBSD fmtlib/fmt#3881, 'fmt::detail::string_scan_buffer' has virtual functions but non-virtual destructor [-Werror,-Wnon-virtual-dtor] fmtlib/fmt#3884, xchar.h wide strings are broken in VS 2022 preview 17.10 fmtlib/fmt#3898, Fix make_format_args ambiguous call fmtlib/fmt#3899, Replace std::fill_n with fmt::detail::fill_n fmtlib/fmt#3909, Fix: enable FMT_NORETURN without exception support too fmtlib/fmt#3917, Resolved warning C4127: conditional expression is constant fmtlib/fmt#3923, Fix mix-up of 'FMT_BEGIN_EXPORT' and 'namespace detail' fmtlib/fmt#3924, fmt::format_to + FMT_STRING with wide characters fails to compile fmtlib/fmt#3925, Resolved warning C4996: 'fileno': The POSIX name for this item is dep… fmtlib/fmt#3930, Fix format_to + FMT_STRING for wide character type fmtlib/fmt#3931, Fix warnings from MSVC fmtlib/fmt#3933, FMT_USE_NONTYPE_TEMPLATE_ARGS detection is wrong on trunk fmtlib/fmt#3935, Fix FMT_USE_NONTYPE_TEMPLATE_ARGS define back fmtlib/fmt#3937, Resolved warning C4127: conditional expression is constant fmtlib/fmt#3967, Fix regression in #3710 fmtlib/fmt#3968, MSVC 17.10.0 + modules cannot find definition fmtlib/fmt#3972, is_convertible_v -> is_convertible::value fmtlib/fmt#3983, Ability to force use of fallback_file fmtlib/fmt#3992, Added generator expression to /utf-8 compile option fmtlib/fmt#3995, Add FMT_FORCE_FALLBACK_FILE to force the use of fallback_file fmtlib/fmt#4009, Suppress a bogus warning in MSVC fmtlib/fmt#4023). Thanks @hmbj, @phprus, @res2k, @Baardi, @matt77hias, @waywardmonkeys, @hmbj, @yakra, @prlw1, @Arghnews, @mtillmann0, @ShifftC, @eepp, @jimmy-park and @ChristianGebhardt.

[chenrui333]

• need to do rev bumps after edencommon fb303 fbthrift fizz folly mvfst proxygen wangle watchman 2024.07.01.00 #176180

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[chenrui333]

#176514