D2372R1: Fixing locale handling in chrono formatters #1891
Description
Describe the bug
Chrono formatting depends on locale by default and doesn't provide control over locale which is inconsistent with all the other standard formatters (https://cplusplus.github.io/LWG/issue3547).
Command-line test case
C:\test>type test.cc
#include <chrono>
#include <format>
#include <iostream>
int main() {
std::locale::global(std::locale("ru_RU"));
std::cout << std::format("{}\n", 0.042);
std::cout << std::format("{:%S}\n", std::chrono::milliseconds(42));
}
C:\test>cl test.cc /std:c++latest /I STL/stl/inc STL/stl/src/format.cpp /EHsc
Microsoft (R) C/C++ Optimizing Compiler Version 19.29.29917 for x64
Copyright (C) Microsoft Corporation. All rights reserved.
/std:c++latest is provided as a preview of language features from the latest C++
working draft, and we're eager to hear about bugs and suggestions for improvements.
However, note that these features are provided as-is without support, and subject
to changes or removal as the working draft evolves. See
https://go.microsoft.com/fwlink/?linkid=2045807 for details.
cl : Command line warning D9026 : options apply to entire command line
test.cc
format.cpp
Generating Code...
Microsoft (R) Incremental Linker Version 14.29.29917.0
Copyright (C) Microsoft Corporation. All rights reserved.
/out:test.exe
test.obj
format.obj
C:\test>test
0.042
00,042
Expected behavior
Expected the output to be
0.042
00.042
i.e. not depend on the locale.
STL version