test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/ok.pass.cpp

//===----------------------------------------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17

// <chrono>
// class month_day;

// constexpr bool ok() const noexcept;
//  Returns: true if m_.ok() is true, 1d <= d_, and d_ is less than or equal to the
//    number of days in month m_; otherwise returns false. 
//  When m_ == February, the number of days is considered to be 29.

#include <chrono>
#include <type_traits>
#include <cassert>

#include "test_macros.h"

int main()
{
    using day       = std::chrono::day;
    using month     = std::chrono::month;
    using month_day = std::chrono::month_day;

    ASSERT_NOEXCEPT(                std::declval<const month_day>().ok());
    ASSERT_SAME_TYPE(bool, decltype(std::declval<const month_day>().ok()));

    static_assert(!month_day{}.ok(),                         "");
    static_assert( month_day{std::chrono::May, day{2}}.ok(), "");

    assert(!(month_day(std::chrono::April, day{0}).ok()));

    assert( (month_day{std::chrono::March, day{1}}.ok()));
    for (unsigned i = 1; i <= 12; ++i)
    {
        const bool is31 = i == 1 || i == 3 || i == 5 || i == 7 || i == 8 || i == 10 || i == 12;
        assert(!(month_day{month{i}, day{ 0}}.ok()));
        assert( (month_day{month{i}, day{ 1}}.ok()));
        assert( (month_day{month{i}, day{10}}.ok()));
        assert( (month_day{month{i}, day{29}}.ok()));
        assert( (month_day{month{i}, day{30}}.ok()) == (i != 2));
        assert( (month_day{month{i}, day{31}}.ok()) == is31);
        assert(!(month_day{month{i}, day{32}}.ok()));
    }

//  If the month is not ok, all the days are bad
    for (unsigned i = 1; i <= 35; ++i)
        assert(!(month_day{month{13}, day{i}}.ok()));
}