llvm/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_defer_lock.pass.cpp

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// <mutex>

// template <class Mutex> class unique_lock;

// unique_lock(mutex_type& m, defer_lock_t);

#include <cassert>
#include <memory>
#include <mutex>
#include <type_traits>

#include "checking_mutex.h"
#include "test_macros.h"

#if TEST_STD_VER >= 11
static_assert(
    std::is_nothrow_constructible<std::unique_lock<checking_mutex>, checking_mutex&, std::defer_lock_t>::value, "");
#endif

int main(int, char**) {
  checking_mutex m;
  std::unique_lock<checking_mutex> lk(m, std::defer_lock_t());
  assert(m.last_try == checking_mutex::none);
  assert(lk.mutex() == std::addressof(m));
  assert(lk.owns_lock() == false);

  return 0;
}