libcxx/test/std/time/time.point/time.point.nonmember/op_-duration.pass.cpp

   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>
  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
  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 }