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 // explicit operator bool() const noexcept;
14 
15 #include <cassert>
16 #include <mutex>
17 #include <type_traits>
18 
19 #include "checking_mutex.h"
20 #include "test_macros.h"
21 
22 #if TEST_STD_VER >= 11
23 static_assert(noexcept(static_cast<bool>(std::declval<std::unique_lock<checking_mutex>&>())), "");
24 #endif
25 
26 int main(int, char**) {
27   static_assert(std::is_constructible<bool, std::unique_lock<checking_mutex> >::value, "");
28   static_assert(!std::is_convertible<std::unique_lock<checking_mutex>, bool>::value, "");
29 
30   checking_mutex mux;
31   const std::unique_lock<checking_mutex> lk0; // Make sure `operator bool()` is `const`
32   assert(!static_cast<bool>(lk0));
33   std::unique_lock<checking_mutex> lk1(mux);
34   assert(static_cast<bool>(lk1));
35   lk1.unlock();
36   assert(!static_cast<bool>(lk1));
37 
38   ASSERT_NOEXCEPT(static_cast<bool>(lk0));
39 
40   return 0;
41 }
42