member_swap.pass.cpp revision e779e31468999c7ef69f424a2b8271969833df28 
1//===----------------------------------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is dual licensed under the MIT and the University of Illinois Open
6// Source Licenses. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// UNSUPPORTED: libcpp-has-no-threads
11// UNSUPPORTED: c++98, c++03, c++11
12
13// <shared_mutex>
14
15// template <class Mutex> class shared_lock;
16
17// void swap(shared_lock& u) noexcept;
18
19#include <shared_mutex>
20#include <cassert>
21
22struct mutex
23{
24    void lock_shared() {}
25    void unlock_shared() {}
26};
27
28mutex m;
29
30int main()
31{
32    std::shared_lock<mutex> lk1(m);
33    std::shared_lock<mutex> lk2;
34    lk1.swap(lk2);
35    assert(lk1.mutex() == nullptr);
36    assert(lk1.owns_lock() == false);
37    assert(lk2.mutex() == &m);
38    assert(lk2.owns_lock() == true);
39    static_assert(noexcept(lk1.swap(lk2)), "member swap must be noexcept");
40}
41