libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/nonmember_swap.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 // <mutex>
  10
  11 // template <class Mutex> class unique_lock;
  12
  13 // template <class Mutex>
  14 //   void swap(unique_lock<Mutex>& x, unique_lock<Mutex>& y);
  15
  16 #include <cassert>
  17 #include <memory>
  18 #include <mutex>
  19
  20 #include "checking_mutex.h"
  21 #include "test_macros.h"
  22
  23 #if TEST_STD_VER >= 11
  24 static_assert(noexcept(swap(std::declval<std::unique_lock<checking_mutex>&>(),
  25                             std::declval<std::unique_lock<checking_mutex>&>())),
  26               "");
  27 #endif
  28
  29 int main(int, char**) {
  30   checking_mutex mux;
  31   std::unique_lock<checking_mutex> lock1(mux);
  32   std::unique_lock<checking_mutex> lock2;
  33
  34   swap(lock1, lock2);
  35
  36   assert(lock1.mutex() == nullptr);
  37   assert(!lock1.owns_lock());
  38   assert(lock2.mutex() == std::addressof(mux));
  39   assert(lock2.owns_lock() == true);
  40
  41   return 0;
  42 }