#include <gtest/gtest.h>
#include <m5_utility/stl/optional.hpp>

TEST(Optional, Nullopt)
{
    m5::stl::optional<int> o1 = m5::stl::nullopt;
    m5::stl::optional<int> o2{m5::stl::nullopt};
    m5::stl::optional<int> o3(m5::stl::nullopt);
    m5::stl::optional<int> o4 = {m5::stl::nullopt};

    EXPECT_TRUE(!o1);
    EXPECT_TRUE(!o2);
    EXPECT_TRUE(!o3);
    EXPECT_TRUE(!o4);

    EXPECT_TRUE(!std::is_default_constructible<m5::stl::nullopt_t>::value);
}