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// class day;
12
13// constexpr day operator-(const day& x, const days& y) noexcept;
14// Returns: x + -y.
15//
16// constexpr days operator-(const day& x, const day& y) noexcept;
17// Returns: days{int(unsigned{x}) - int(unsigned{y}).
18
19#include <chrono>
20#include <cassert>
21#include <type_traits>
22#include <utility>
23
24#include "test_macros.h"
25
26using day = std::chrono::day;
27using days = std::chrono::days;
28
29constexpr bool test() {
30 day dy{12};
31 for (unsigned i = 0; i <= 10; ++i) {
32 day d1 = dy - days{i};
33 days off = dy - day{i};
34 assert(static_cast<unsigned>(d1) == 12 - i);
35 assert(off.count() == static_cast<int>(12 - i)); // days is signed
36 }
37
38 return true;
39}
40
41int main(int, char**) {
42 ASSERT_NOEXCEPT(std::declval<day>() - std::declval<days>());
43 ASSERT_NOEXCEPT(std::declval<day>() - std::declval<day>());
44
45 ASSERT_SAME_TYPE(day, decltype(std::declval<day>() - std::declval<days>()));
46 ASSERT_SAME_TYPE(days, decltype(std::declval<day>() - std::declval<day>()));
47
48 test();
49 static_assert(test());
50
51 return 0;
52}
53

source code of libcxx/test/std/time/time.cal/time.cal.day/time.cal.day.nonmembers/minus.pass.cpp