Perform localized comparison on Windows via wstring #40062
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This was referenced May 3, 2020
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In light of the discussion in #40041 I've updated this PR to apply to Windows only. That looks like it ought to give us the best results there. So I'm marking this one ready for review. |
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Added some tests to this PR. |
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On Windows the existing solution for localized comparison seems to do the wrong thing, but evidence suggests that comparison of wstring should work. Convert the strings before comparison on Windows. At the same time, do the reverse conversion on MacOS (this won't actually be used anywhere in the current code, but it seemse a good idea to implement it while we had the experimental data to suggest it was necessary. See CleverRaven#40041 for more discussion.
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It works, case-insensitive. Thanks! |
This was referenced May 10, 2020
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Summary
SUMMARY: None
Purpose of change
On OS X and Windows the existing solution for localized comparison seems to be struggling.
@akirashirosawa found a workaround for OS X. This is intended to be a workaround for Windows. It's necessary because on Windows the locale cannot be assumed to be UTF-8 (indeed, it almost certainly isn't).
Describe the solution
Perform the comparison on
std::wstringrather than string, which should sidestep any character encoding issues.Describe alternatives you've considered
We could do a similar trick with
std::u32string, but I suspect that would be poorly supported on Windows.Testing
I can't test, but @ScampsAdams experiment here suggest that this should work.