xref: /llvm-project/libcxx/test/std/thread/thread.jthread/get_stop_token.pass.cpp (revision 121ed5c1985356436d0040dbe81bca26992b1fae)
1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // UNSUPPORTED: no-threads
10 // UNSUPPORTED: c++03, c++11, c++14, c++17
11 // XFAIL: availability-synchronization_library-missing
12 
13 // [[nodiscard]] stop_token get_stop_token() const noexcept;
14 
15 #include <cassert>
16 #include <concepts>
17 #include <stop_token>
18 #include <thread>
19 #include <type_traits>
20 #include <utility>
21 
22 #include "make_test_thread.h"
23 #include "test_macros.h"
24 
25 static_assert(noexcept(std::declval<const std::jthread&>().get_stop_token()));
26 
27 int main(int, char**) {
28   // Represents a thread
29   {
30     std::jthread jt                                 = support::make_test_jthread([] {});
31     auto ss                                         = jt.get_stop_source();
32     std::same_as<std::stop_token> decltype(auto) st = std::as_const(jt).get_stop_token();
33 
34     assert(st.stop_possible());
35     assert(!st.stop_requested());
36     ss.request_stop();
37     assert(st.stop_requested());
38   }
39 
40   // Does not represent a thread
41   {
42     const std::jthread jt{};
43     std::same_as<std::stop_token> decltype(auto) st = jt.get_stop_token();
44 
45     assert(!st.stop_possible());
46   }
47 
48   return 0;
49 }
50