All supported compilers that support C++20 now support concepts. So, remove
`_LIB_LIBCPP_HAS_NO_CONCEPTS` in favor of `_LIBCPP_STD_VER > 17`. Similarly in
the tests, remove `// UNSUPPORTED: libcpp-no-concepts`.
Differential Revision: https://reviews.llvm.org/D121528
The "user-defined conversion by implicit constructor" codepath is already
handled by `B(int)`; we don't need to test `A(const A&)` a second time
via `DA` (nor the isomorphic case with `DB`).
We don't need `&` anywhere in this test.
Generally, `operator()` should be const; this test needn't be special.
(No functional change in test coverage.)
This should be clearer, instead of relying on rules for implicit
conversions regarding built in float/integer types.
Differential Revision: https://reviews.llvm.org/D99928
MSVC had a bug regarding preferring intergral conversions over
floating conversions. This is fixed in MSVC 19.28 and newer. Clang in
MSVC mode so far only mimics the old, buggy behaviour, but will
hopefully soon be fixed to comply with the new behaviour too
(see https://reviews.llvm.org/D99663).
Make the negative test to use a distinctly different type,
leaving checks for compiler specific bugs out of the libcxx test.
Differential Revision: https://reviews.llvm.org/D99641
The tests for `std::invocable` and `std::regular_invocable` were
woefully incomplete. This patch closes many of the gaps (though some
probably remain).
Differential Revision: https://reviews.llvm.org/D99398
moves tests into directories matching their stable names so that the
tests can reflect the concept name
Differential Revision: https://reviews.llvm.org/D99104