Implement LWG-3070

[DailyShana]

fix #333

[Stephan T. Lavavej (StephanTLavavej)]

Thanks for implementing this LWG issue resolution and adding test coverage! Looks good to me. I have an optional suggestion.

[DailyShana]

trying to use std::any_of in the extracted function but cannot pass tests

bool _Relative_path_contains_root_name(const path& _Path) {
    return _STD any_of(_Path.relative_path().begin(), _Path.relative_path().end(),
        [] (const path& _File_name) { return !_Parse_root_name(_File_name.native()).empty(); });
}

out put:

xstring(1988) : Assertion failed: string iterators in range are from different containers

or

Test step failed unexpectedly.
Command: "***\STL\out\build\x64\tests\std\tests\P0218R1_filesystem\05\P0218R1_filesystem.exe"
Exit Code: 3221226505

[Billy O'Neal (BillyONeal)]

DailyShana That's because you are calling relative_path() more than once; each call is creating a temporary path. Ideally this shouldn't need to call relative_path at all; it should use the underlying parsing machinery to avoid separate memory allocations here.

[DailyShana]

DailyShana That's because you are calling relative_path() more than once; each call is creating a temporary path. Ideally this shouldn't need to call relative_path at all; it should use the underlying parsing machinery to avoid separate memory allocations here.

I see, I didn't notice the effect of calling relative_path(), and I tried using parsing machinery and found loop relative_path is more clear and simple but I didn't notice the memory allocations.

[Casey Carter (CaseyCarter)]

Congratulations on your first contribution to the STL!