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 weekday;
12
13// constexpr weekday operator-(const weekday& x, const days& y) noexcept;
14// Returns: x + -y.
15//
16// constexpr days operator-(const weekday& x, const weekday& y) noexcept;
17// Returns: If x.ok() == true and y.ok() == true, returns a value d in the range
18// [days{0}, days{6}] satisfying y + d == x.
19// Otherwise the value returned is unspecified.
20// [Example: Sunday - Monday == days{6}. -end example]
21
22#include <chrono>
23#include <cassert>
24#include <type_traits>
25#include <utility>
26
27#include "test_macros.h"
28#include "../../euclidian.h"
29
30using weekday = std::chrono::weekday;
31using days = std::chrono::days;
32
33constexpr bool test() {
34 for (unsigned i = 0; i <= 6; ++i)
35 for (unsigned j = 0; j <= 6; ++j) {
36 weekday wd = weekday{i} - days{j};
37 assert(wd + days{j} == weekday{i});
38 assert((wd.c_encoding() == euclidian_subtraction<unsigned, 0, 6>(i, j)));
39 }
40
41 for (unsigned i = 0; i <= 6; ++i)
42 for (unsigned j = 0; j <= 6; ++j) {
43 days d = weekday{j} - weekday{i};
44 assert(weekday{i} + d == weekday{j});
45 }
46
47 // Check the example
48 assert(weekday{0} - weekday{1} == days{6});
49
50 return true;
51}
52
53int main(int, char**) {
54 ASSERT_NOEXCEPT(std::declval<weekday>() - std::declval<days>());
55 ASSERT_SAME_TYPE(weekday, decltype(std::declval<weekday>() - std::declval<days>()));
56
57 ASSERT_NOEXCEPT(std::declval<weekday>() - std::declval<weekday>());
58 ASSERT_SAME_TYPE(days, decltype(std::declval<weekday>() - std::declval<weekday>()));
59
60 test();
61 static_assert(test());
62
63 return 0;
64}
65

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