Implement LWG-3710: The end of chunk_view for input ranges can be const

[gogim1]

Implements the proposed resolution of LWG-3710

[StephanTLavavej]

Welcome to the microsoft/STL repo!

The P2442R1_views_chunk test is failing with:

C:\a\1\s\tests\std\tests\P2442R1_views_chunk\test.cpp(200): error C2338: static_assert failed: 'CanMemberEnd<const R> == forward_range<const V>'
C:\a\1\s\tests\std\tests\P2442R1_views_chunk\test.cpp(204): error C2338: static_assert failed: 'common_range<R> == (common_range<const V> && (sized_range<const V> || !bidirectional_range<const V>) )'
C:\a\1\s\tests\std\tests\P2442R1_views_chunk\test.cpp(202): error C7601: the associated constraints are not satisfied

Please ensure that this test passes locally before pushing changes. Let us know if you need assistance!

[frederick-vs-ja]

I think this test file should also be changed.

STL/tests/std/tests/P2442R1_views_chunk/test.cpp

Line 200 in ef62d3f

STATIC_ASSERT(CanMemberEnd<const R> == forward_range<const V>);

Due to LWG-3710, CanMemberEnd<const R> becomes true if const V is an input_range.

---

Edit:

STL/tests/std/tests/P2442R1_views_chunk/test.cpp

Line 205 in ef62d3f

common_range<R> == (common_range<const V> && (sized_range<const V> || !bidirectional_range<const V>) ));

And forward_range should be detected in this line.

[ghost]

All CLA requirements met.

[CaseyCarter]

This looks good, other than the formatting issue.

[gogim1]

Thanks everyone. Without your help, I could not have finished this patch.

[StephanTLavavej]

Thanks, this looks great! I'll push minor changes for nitpicky style issues.

[StephanTLavavej]

FYI @CaseyCarter, I pushed very minor changes after you approved.

[StephanTLavavej]

I'm mirroring this to the MSVC-internal repo - please notify me if any further changes are pushed.

[StephanTLavavej]

Thanks for improving <ranges> conformance, and congratulations on your first microsoft/STL commit! 😻 🎉 🚀

This change will be available in VS 2022 17.4 Preview 2.