xref: /llvm-project/libcxx/test/std/utilities/expected/expected.unexpected/assign/assign.move.pass.cpp (revision 6a54dfbfe534276d644d7f9c027f0deeb748dd53)
1e356f681SHui Xie //===----------------------------------------------------------------------===//
2*6a54dfbfSLouis Dionne //
3e356f681SHui Xie // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4e356f681SHui Xie // See https://llvm.org/LICENSE.txt for license information.
5e356f681SHui Xie // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6e356f681SHui Xie //
7e356f681SHui Xie //===----------------------------------------------------------------------===//
8e356f681SHui Xie 
9e356f681SHui Xie // UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
10e356f681SHui Xie 
11e356f681SHui Xie // constexpr unexpected& operator=(unexpected&&) = default;
12e356f681SHui Xie 
13e356f681SHui Xie #include <cassert>
14e356f681SHui Xie #include <expected>
15e356f681SHui Xie #include <utility>
16e356f681SHui Xie 
17e356f681SHui Xie struct Error {
18e356f681SHui Xie   int i;
19e356f681SHui Xie   constexpr Error(int ii) : i(ii) {}
20e356f681SHui Xie   constexpr Error& operator=(Error&& other) {
21e356f681SHui Xie     i       = other.i;
22e356f681SHui Xie     other.i = 0;
23e356f681SHui Xie     return *this;
24e356f681SHui Xie   }
25e356f681SHui Xie };
26e356f681SHui Xie 
27e356f681SHui Xie constexpr bool test() {
28e356f681SHui Xie   std::unexpected<Error> unex1(4);
29e356f681SHui Xie   std::unexpected<Error> unex2(5);
30e356f681SHui Xie   unex1 = std::move(unex2);
31e356f681SHui Xie   assert(unex1.error().i == 5);
32e356f681SHui Xie   assert(unex2.error().i == 0);
33e356f681SHui Xie   return true;
34e356f681SHui Xie }
35e356f681SHui Xie 
36e356f681SHui Xie int main(int, char**) {
37e356f681SHui Xie   test();
38e356f681SHui Xie   static_assert(test());
39e356f681SHui Xie   return 0;
40e356f681SHui Xie }
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