xref: /llvm-project/libcxx/test/std/time/time.point/time.point.nonmember/op_-duration.pass.cpp (revision d1a461dbb2293d9258d400b5426f610bb5191228)
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 // <chrono>
10 
11 // time_point
12 
13 // template <class Clock, class Duration1, class Rep2, class Period2>
14 //   time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2>>::type>
15 //   operator-(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
16 
17 #include <chrono>
18 #include <cassert>
19 #include <cstdint>
20 
21 #include "test_macros.h"
22 
23 template <class D>
test2739()24 void test2739()  // LWG2739
25 {
26     typedef std::chrono::time_point<std::chrono::system_clock> TimePoint;
27     typedef std::chrono::duration<D> Dur;
28     const Dur d(5);
29     TimePoint t0 = std::chrono::system_clock::from_time_t(200);
30     TimePoint t1 = t0 - d;
31     assert(t1 < t0);
32 }
33 
main(int,char **)34 int main(int, char**)
35 {
36     typedef std::chrono::system_clock Clock;
37     typedef std::chrono::milliseconds Duration1;
38     typedef std::chrono::microseconds Duration2;
39     {
40     std::chrono::time_point<Clock, Duration1> t1(Duration1(3));
41     std::chrono::time_point<Clock, Duration2> t2 = t1 - Duration2(5);
42     assert(t2.time_since_epoch() == Duration2(2995));
43     }
44 #if TEST_STD_VER > 11
45     {
46     constexpr std::chrono::time_point<Clock, Duration1> t1(Duration1(3));
47     constexpr std::chrono::time_point<Clock, Duration2> t2 = t1 - Duration2(5);
48     static_assert(t2.time_since_epoch() == Duration2(2995), "");
49     }
50 #endif
51     test2739<std::int32_t>();
52     test2739<std::uint32_t>();
53 
54   return 0;
55 }
56