| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // UNSUPPORTED: c++98, c++03, c++11, c++14 |
| |
| // type_traits |
| |
| // is_swappable |
| |
| #include <type_traits> |
| #include <vector> |
| #include "test_macros.h" |
| |
| namespace MyNS { |
| |
| // Make the test types non-copyable so that generic std::swap is not valid. |
| struct A { |
| A(A const&) = delete; |
| A& operator=(A const&) = delete; |
| }; |
| |
| struct B { |
| B(B const&) = delete; |
| B& operator=(B const&) = delete; |
| }; |
| |
| void swap(A&, A&) noexcept {} |
| void swap(B&, B&) {} |
| |
| struct M { |
| M(M const&) = delete; |
| M& operator=(M const&) = delete; |
| }; |
| |
| void swap(M&&, M&&) noexcept {} |
| |
| struct ThrowingMove { |
| ThrowingMove(ThrowingMove&&) {} |
| ThrowingMove& operator=(ThrowingMove&&) { return *this; } |
| }; |
| |
| } // namespace MyNS |
| |
| int main(int, char**) |
| { |
| using namespace MyNS; |
| { |
| // Test that is_swappable applies an lvalue reference to the type. |
| static_assert(std::is_nothrow_swappable<int>::value, ""); |
| static_assert(std::is_nothrow_swappable<int&>::value, ""); |
| static_assert(!std::is_nothrow_swappable<M>::value, ""); |
| static_assert(!std::is_nothrow_swappable<M&&>::value, ""); |
| } |
| { |
| // Test that it correctly deduces the noexcept of swap. |
| static_assert(std::is_nothrow_swappable<A>::value, ""); |
| static_assert(!std::is_nothrow_swappable<B>::value |
| && std::is_swappable<B>::value, ""); |
| static_assert(!std::is_nothrow_swappable<ThrowingMove>::value |
| && std::is_swappable<ThrowingMove>::value, ""); |
| } |
| { |
| // Test that it doesn't drop the qualifiers |
| static_assert(!std::is_nothrow_swappable<const A>::value, ""); |
| } |
| { |
| // test non-referenceable types |
| static_assert(!std::is_nothrow_swappable<void>::value, ""); |
| static_assert(!std::is_nothrow_swappable<int() const>::value, ""); |
| static_assert(!std::is_nothrow_swappable<int(int, ...) const &>::value, ""); |
| } |
| { |
| // test for presence of is_nothrow_swappable_v |
| static_assert(std::is_nothrow_swappable_v<int>, ""); |
| static_assert(!std::is_nothrow_swappable_v<void>, ""); |
| } |
| |
| return 0; |
| } |