The tests for these are just copy-pasted from the tests for std::{strong,weak,partial}_order,
and then I added an extra clause in each (test_2()) to test the stuff that's not just the same
as std::*_order.
This also includes the fix for https://wg21.link/LWG3465 (which falls naturally out of the
"you must write it three times" style, but I've added test cases for it also).
There is an action item here to go back and give good diagnostics for SFINAE failures
in these CPOs. I've filed this as https://github.com/llvm/llvm-project/issues/53456 .
Differential Revision: https://reviews.llvm.org/D111514
This will detect if someone writes `inline auto cpo =` instead of
`inline constexpr auto cpo =`. I don't know how that'd be possible,
but it's easy to test, so let's test it.
Add test for various customization point object properties as defined by
the Standard. Test various CPOs from `<ranges>`, `<iterator>`,
`<concepts>`, etc.
The test is mostly from https://reviews.llvm.org/D107036 and split up
into this.
Differential Revision: https://reviews.llvm.org/D115588
Arthur O'Dwyer