[libcxx-commits] [libcxx] [libc++] Make sure `flat_{multi}map::key_compare` handle `boolean-testable` correctly (PR #132621)

[Hewill Kang via libcxx-commits]

hewillk wrote:

> Can we add tests similarly to what we do in `libcxx/test/std/algorithms/ranges_robust_against_nonbool.compile.pass.cpp`?

No problem, I can handle this when I have the time .

https://github.com/llvm/llvm-project/pull/132621