53 lines · 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-exception6//7//===----------------------------------------------------------------------===//8//9// UNSUPPORTED: no-threads10// UNSUPPORTED: c++03, c++11, c++14, c++1711 12// [[nodiscard]] bool joinable() const noexcept;13 14#include <atomic>15#include <cassert>16#include <concepts>17#include <thread>18#include <type_traits>19 20#include "make_test_thread.h"21#include "test_macros.h"22 23static_assert(noexcept(std::declval<const std::jthread&>().joinable()));24 25int main(int, char**) {26 // Default constructed27 {28 const std::jthread jt;29 std::same_as<bool> decltype(auto) result = jt.joinable();30 assert(!result);31 }32 33 // Non-default constructed34 {35 const std::jthread jt = support::make_test_jthread([] {});36 std::same_as<bool> decltype(auto) result = jt.joinable();37 assert(result);38 }39 40 // Non-default constructed41 // the thread of execution has not finished42 {43 std::atomic_bool done = false;44 const std::jthread jt = support::make_test_jthread([&done] { done.wait(false); });45 std::same_as<bool> decltype(auto) result = jt.joinable();46 done = true;47 done.notify_all();48 assert(result);49 }50 51 return 0;52}53