1 //===----------------------------------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 // UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
10
11 // <chrono>
12 // class year_month_day;
13
14 // constexpr year_month_day operator-(const year_month_day& ymd, const years& dy) noexcept;
15 // Returns: ymd + (-dy)
16
17
18 #include <chrono>
19 #include <type_traits>
20 #include <cassert>
21
22 #include "test_macros.h"
23
24 #include <iostream>
25
test_constexpr()26 constexpr bool test_constexpr ()
27 {
28 std::chrono::year_month_day ym0{std::chrono::year{1234}, std::chrono::January, std::chrono::day{12}};
29 std::chrono::year_month_day ym1 = ym0 - std::chrono::years{10};
30 return
31 ym1.year() == std::chrono::year{1234-10}
32 && ym1.month() == std::chrono::January
33 && ym1.day() == std::chrono::day{12}
34 ;
35 }
36
main()37 int main()
38 {
39 using year = std::chrono::year;
40 using month = std::chrono::month;
41 using day = std::chrono::day;
42 using year_month_day = std::chrono::year_month_day;
43 using years = std::chrono::years;
44
45 ASSERT_NOEXCEPT( std::declval<year_month_day>() - std::declval<years>());
46 ASSERT_SAME_TYPE(year_month_day, decltype(std::declval<year_month_day>() - std::declval<years>()));
47
48 constexpr month January = std::chrono::January;
49
50 static_assert(test_constexpr(), "");
51
52 year_month_day ym{year{1234}, January, day{10}};
53 for (int i = 0; i <= 10; ++i)
54 {
55 year_month_day ym1 = ym - years{i};
56 assert(static_cast<int>(ym1.year()) == 1234 - i);
57 assert(ym1.month() == January);
58 assert(ym1.day() == day{10});
59 }
60 }
61