libcxx/test/std/thread/thread.jthread/get_stop_token.pass.cpp

   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 }