libcxx/test/std/time/time.duration/time.duration.special/zero.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 // duration
  12
  13 // static constexpr duration zero(); // noexcept after C++17
  14
  15 #include <chrono>
  16 #include <cassert>
  17
  18 #include "test_macros.h"
  19 #include "../../rep.h"
  20
  21 template <class D>
  22 void test()
  23 {
  24     LIBCPP_ASSERT_NOEXCEPT(std::chrono::duration_values<typename D::rep>::zero());
  25 #if TEST_STD_VER > 17
  26     ASSERT_NOEXCEPT(       std::chrono::duration_values<typename D::rep>::zero());
  27 #endif
  28     {
  29     typedef typename D::rep DRep;
  30     DRep zero_rep = std::chrono::duration_values<DRep>::zero();
  31     assert(D::zero().count() == zero_rep);
  32     }
  33 #if TEST_STD_VER >= 11
  34     {
  35     typedef typename D::rep DRep;
  36     constexpr DRep zero_rep = std::chrono::duration_values<DRep>::zero();
  37     static_assert(D::zero().count() == zero_rep, "");
  38     }
  39 #endif
  40 }
  41
  42 int main(int, char**)
  43 {
  44     test<std::chrono::duration<int> >();
  45     test<std::chrono::duration<Rep> >();
  46
  47   return 0;
  48 }