xref: /llvm-project/libcxx/test/std/thread/thread.stoptoken/stopsource/stop_possible.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]] bool stop_possible() const noexcept;
14 // Returns: true if *this has ownership of a stop state; otherwise, false.
15 
16 #include <cassert>
17 #include <stop_token>
18 #include <type_traits>
19 
20 #include "test_macros.h"
21 
22 template <class T>
23 concept IsStopPossibleNoexcept = requires(const T& t) {
24   { t.stop_possible() } noexcept;
25 };
26 
27 static_assert(IsStopPossibleNoexcept<std::stop_source>);
28 
29 int main(int, char**) {
30   // no state
31   {
32     const std::stop_source st{std::nostopstate};
33     assert(!st.stop_possible());
34   }
35 
36   // with state
37   {
38     const std::stop_source st;
39     assert(st.stop_possible());
40   }
41 
42   return 0;
43 }
44