[libc++] Cleanup non-portable std::any tests

[CaseyCarter]

Summary

Cleanup nonportable behavior in tests for std::any

Fixes MS issues 63, 64, and 65.

test/std/utilities/any/any.class/any.cons/move.pass.cpp:

• "Moves are always destructive" is not a portable assumption; check with LIBCPP_ASSERT.

test/std/utilities/any/any.class/any.cons/value.pass.cpp:
test/libcxx/utilities/any/any.class/any.cons/value.pass.cpp:

• The standard does not forbid initializing std::any from any pointer-to-function type. The DecayTag test is a libc++ extension (at best); factor it out into a test in the libcxx hierarchy.

test/std/utilities/any/any.class/any.modifiers/swap.pass.cpp:

• Self-swap is not specified to perform no moves; check with LIBCPP_ASSERT.

[CaseyCarter]

test/libcxx/utilities/any/any.class/any.cons/value.pass.cpp

36 ↗

(On Diff #75934)

I'm generously calling this a "libc++ extension." From my interpretation of N4606, LWG2744, and LWG2754, this appears to be a bug.

[EricWF]

test/libcxx/utilities/any/any.class/any.cons/value.pass.cpp

1 ↗

(On Diff #75934)

Just kill this test entirely. I'm going to change the behavior shortly.

[CaseyCarter]

Cleanup nonportable behavior in tests for std::any

Fixes MS issues 63, 64, and 65.

test/std/utilities/any/any.class/any.cons/move.pass.cpp:

• "Moves are always destructive" is not a portable assumption; check with LIBCPP_ASSERT.

test/std/utilities/any/any.class/any.cons/value.pass.cpp:

• The standard does not forbid initializing std::any from any pointer-to-function type. Remove the non-conforming DecayTag test.

test/std/utilities/any/any.class/any.modifiers/swap.pass.cpp:

• Self-swap is not specified to perform no moves; check with LIBCPP_ASSERT.

[CaseyCarter]

DecayTag destroyed.

[EricWF]

test/libcxx/utilities/any/any.class/any.cons/value.pass.cpp

36 ↗

(On Diff #75934)

I agree. I want this to be a diagnostic of some sort. Preferably a static warning because if you've managed to decay the tags your in for a treat.

test/std/utilities/any/any.class/any.cons/move.pass.cpp

         assert(Type::moved == 1 || Type::moved == 2); // zero or more move operations can be performed.
         assert(Type::copied == 0); // no copies can be performed.
         assert(Type::count == 1 + a.has_value());
-        assertEmpty(a); // Moves are always destructive.
         assertContains<Type>(a2, 42);
+        LIBCPP_ASSERT(!a.has_value()); // Moves are always destructive.
         if (a.has_value())
             assertContains<Type>(a, 0);
     }

test/std/utilities/any/any.class/any.cons/value.pass.cpp

         static_assert(!std::is_constructible<std::any, T>::value, "");
     }
     {
-        using DecayTag = std::decay_t<BadTag>;
-        static_assert(!std::is_constructible<std::any, DecayTag>::value, "");
-    }
-    {
         // Test that the ValueType&& constructor SFINAE's away when the
         // argument is non-copyable
         struct NoCopy {

test/std/utilities/any/any.class/any.modifiers/swap.pass.cpp

         assertContains<T>(a, 42);
         assert(T::count == 1);
         assert(T::copied == 0);
-        assert(T::moved == 0);
+        LIBCPP_ASSERT(T::moved == 0);
     }
     assert(small::count == 0);
     { // large

         T::reset();
         a.swap(a);
         assertContains<T>(a, 42);
-        assert(T::copied == 0);
-        assert(T::moved == 0);
         assert(T::count == 1);
+        assert(T::copied == 0);
+        LIBCPP_ASSERT(T::moved == 0);
     }
     assert(large::count == 0);
 }