LGTM! (You should say "Partially implements P0896R4" in the commit log =))

Ah, I see it. I'll add that bit to libc++ so we don't need special casing in the tests.

In D87459#2265864, @ldionne wrote:

What paper is this? I searched but failed to find a paper this falls off from.

I'm not going to "request changes" since I don't want you to feel like I'm asking for a novel on trivial special member functions. I'm just going to "comment" and race out of the review before someone asks me to do work ;)

Thanks for the help, Louis!

• Remove copy-pasta from RUN line in unparsed-requirements.py.
• Simplify code with +=
• Complete test coverage
• Change line endings to LF in new files

Hack together test.

I attempted to address everything. The test may be terrible - I've used LIT casually but never peeked inside until yesterday - so please don't refrain from telling me how to improve it.

Partially address review comments.

In D60951#2026475, @ldionne wrote:

To be clear, I'm trying to move the test suite towards a generic conformance test suite for the Standard, as opposed to a libc++ test suite that happens to be usable by other Standard Libraries. This change highlights that philosophy.

• Guard tests for components that libc++ doesn't implement with // UNSUPPORTED: libc++ and an appropriate comment.

In D79343#2025211, @ldionne wrote:

Regarding the formatting changes, I personally think we should clang-format all of libc++, libc++abi and libunwind in one go. Then we'd be done with these small issues that add up. And we can even add the revision to .git-blame-ignore-revs.

Format issues addressed.

clang-format new/changed sections of code per policy.

I'm not going to reformat *only* my additions per the clang-format instructions - that would be silly - and I suspect that folks would clang-format all of the tests if they actually wanted them formatted, so I won't format the entire file, either.

Review comments.

LGTM. I'll resign rather than approving so the "real" approvers won't be confused and never look at this.

Missing a bunch of "Add a new header" changes (https://github.com/llvm/llvm-project/blob/master/libcxx/NOTES.TXT#L19-L29).

@STL_MSFT seems to have already fixed this by removing the problem test cases in bf7dc572f199007cbe042d5ea41bcf873dcedd8f. I'll simply abandon this change.

LGTM. (Resigning as reviewer rather than approving to avoid confusing the folks who are actually authorized to approve.)

(I'm not sure how to withdraw my "Request Changes" without approving - I'm not an authorized approver for libc++ - so I'll "Resign as Reviewer" and see if my red X goes away.)

In D68681#1702194, @ldionne wrote:

You have commit access, right? If so, go ahead. Otherwise, LMK and I can commit this for you.

Avoid rather than suppress truncation warnings in unordered_meow deduction guide tests.