libcxx/test/std/thread/thread.jthread/swap.member.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 // void swap(jthread& x) noexcept;
  14
  15 #include <cassert>
  16 #include <thread>
  17 #include <type_traits>
  18
  19 #include "make_test_thread.h"
  20 #include "test_macros.h"
  21
  22 template <class T>
  23 concept IsMemberSwapNoexcept = requires(T& a, T& b) {
  24   { a.swap(b) } noexcept;
  25 };
  26
  27 static_assert(IsMemberSwapNoexcept<std::jthread>);
  28
  29 int main(int, char**) {
  30   // this is default constructed
  31   {
  32     std::jthread t1;
  33     std::jthread t2        = support::make_test_jthread([] {});
  34     const auto originalId2 = t2.get_id();
  35     t1.swap(t2);
  36
  37     assert(t1.get_id() == originalId2);
  38     assert(t2.get_id() == std::jthread::id());
  39   }
  40
  41   // that is default constructed
  42   {
  43     std::jthread t1 = support::make_test_jthread([] {});
  44     std::jthread t2{};
  45     const auto originalId1 = t1.get_id();
  46     t1.swap(t2);
  47
  48     assert(t1.get_id() == std::jthread::id());
  49     assert(t2.get_id() == originalId1);
  50   }
  51
  52   // both not default constructed
  53   {
  54     std::jthread t1        = support::make_test_jthread([] {});
  55     std::jthread t2        = support::make_test_jthread([] {});
  56     const auto originalId1 = t1.get_id();
  57     const auto originalId2 = t2.get_id();
  58     t1.swap(t2);
  59
  60     assert(t1.get_id() == originalId2);
  61     assert(t2.get_id() == originalId1);
  62   }
  63
  64   // both default constructed
  65   {
  66     std::jthread t1;
  67     std::jthread t2;
  68     t1.swap(t2);
  69
  70     assert(t1.get_id() == std::jthread::id());
  71     assert(t2.get_id() == std::jthread::id());
  72   }
  73
  74   return 0;
  75 }