libcxx/test/std/time/time.cal/time.cal.ymd/time.cal.ymd.members/plus_minus_equal_month.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 // UNSUPPORTED: c++03, c++11, c++14, c++17
   9
  10 // <chrono>
  11 // class year_month_day;
  12
  13 // constexpr year_month_day& operator+=(const months& m) noexcept;
  14 // constexpr year_month_day& operator-=(const months& m) noexcept;
  15
  16 #include <chrono>
  17 #include <type_traits>
  18 #include <cassert>
  19
  20 #include "test_macros.h"
  21
  22 using year           = std::chrono::year;
  23 using month          = std::chrono::month;
  24 using day            = std::chrono::day;
  25 using year_month_day = std::chrono::year_month_day;
  26 using months         = std::chrono::months;
  27
  28 constexpr bool test() {
  29   for (unsigned i = 0; i <= 10; ++i) {
  30     year y{1234};
  31     day d{23};
  32     year_month_day ymd(y, month{i}, d);
  33
  34     ymd += months{2};
  35     assert(ymd.year() == y);
  36     assert(ymd.day() == d);
  37     assert(static_cast<unsigned>((ymd).month()) == i + 2);
  38
  39     ymd -= months{1};
  40     assert(ymd.year() == y);
  41     assert(ymd.day() == d);
  42     assert(static_cast<unsigned>((ymd).month()) == i + 1);
  43   }
  44
  45   { // Validate the ok status when the day is not present in the new month.
  46     year_month_day ymd{year{2020}, month{3}, day{31}};
  47     ymd += months{1};
  48     assert((ymd == year_month_day{year{2020}, month{4}, day{31}}));
  49     assert(!ymd.ok());
  50
  51     ymd -= months{1};
  52     assert((ymd == year_month_day{year{2020}, month{3}, day{31}}));
  53     assert(ymd.ok());
  54   }
  55
  56   { // Validate the ok status when the day becomes present in the new month.
  57     year_month_day ymd{year{2020}, month{4}, day{31}};
  58     assert(!ymd.ok());
  59
  60     ymd += months{1};
  61     assert((ymd == year_month_day{year{2020}, month{5}, day{31}}));
  62     assert(ymd.ok());
  63
  64     ymd -= months{2};
  65     assert((ymd == year_month_day{year{2020}, month{3}, day{31}}));
  66     assert(ymd.ok());
  67   }
  68
  69   { // Test year wrapping
  70     year_month_day ymd{year{2020}, month{4}, day{31}};
  71
  72     ymd += months{12};
  73     assert((ymd == year_month_day{year{2021}, month{4}, day{31}}));
  74
  75     ymd -= months{12};
  76     assert((ymd == year_month_day{year{2020}, month{4}, day{31}}));
  77   }
  78
  79   return true;
  80 }
  81
  82 int main(int, char**) {
  83   ASSERT_NOEXCEPT(std::declval<year_month_day&>() += std::declval<months>());
  84   ASSERT_NOEXCEPT(std::declval<year_month_day&>() -= std::declval<months>());
  85
  86   ASSERT_SAME_TYPE(year_month_day&, decltype(std::declval<year_month_day&>() += std::declval<months>()));
  87   ASSERT_SAME_TYPE(year_month_day&, decltype(std::declval<year_month_day&>() -= std::declval<months>()));
  88
  89   test();
  90   static_assert(test());
  91
  92   return 0;
  93 }