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 // UNSUPPORTED: c++03, c++11, c++14, c++17
9
10 // <chrono>
11
12 // template<class Duration>
13 // using sys_time = time_point<system_clock, Duration>;
14 // using sys_seconds = sys_time<seconds>;
15 // using sys_days = sys_time<days>;
16
17 // [Example:
18 // sys_seconds{sys_days{1970y/January/1}}.time_since_epoch() is 0s.
19 // sys_seconds{sys_days{2000y/January/1}}.time_since_epoch() is 946’684’800s, which is 10’957 * 86’400s.
20 // —end example]
21
22
23 #include <chrono>
24 #include <cassert>
25
26 #include "test_macros.h"
27
main(int,char **)28 int main(int, char**)
29 {
30 using system_clock = std::chrono::system_clock;
31 using year = std::chrono::year;
32
33 using seconds = std::chrono::seconds;
34 using minutes = std::chrono::minutes;
35 using days = std::chrono::days;
36
37 using sys_seconds = std::chrono::sys_seconds;
38 using sys_minutes = std::chrono::sys_time<minutes>;
39 using sys_days = std::chrono::sys_days;
40
41 constexpr std::chrono::month January = std::chrono::January;
42
43 ASSERT_SAME_TYPE(std::chrono::sys_time<seconds>, sys_seconds);
44 ASSERT_SAME_TYPE(std::chrono::sys_time<days>, sys_days);
45
46 // Test the long form, too
47 ASSERT_SAME_TYPE(std::chrono::time_point<system_clock, seconds>, sys_seconds);
48 ASSERT_SAME_TYPE(std::chrono::time_point<system_clock, minutes>, sys_minutes);
49 ASSERT_SAME_TYPE(std::chrono::time_point<system_clock, days>, sys_days);
50
51 // Test some well known values
52 sys_days d0 = sys_days{year{1970}/January/1};
53 sys_days d1 = sys_days{year{2000}/January/1};
54 ASSERT_SAME_TYPE(decltype(d0.time_since_epoch()), days);
55 assert( d0.time_since_epoch().count() == 0);
56 assert( d1.time_since_epoch().count() == 10957);
57
58 sys_seconds s0{d0};
59 sys_seconds s1{d1};
60 ASSERT_SAME_TYPE(decltype(s0.time_since_epoch()), seconds);
61 assert( s0.time_since_epoch().count() == 0);
62 assert( s1.time_since_epoch().count() == 946684800L);
63
64 return 0;
65 }
66