compat/test/invoke_r_obj_constexpr_test.cpp

// Copyright 2024 Peter Dimov
// Distributed under the Boost Software License, Version 1.0.
// https://www.boost.org/LICENSE_1_0.txt

#include <boost/compat/invoke.hpp>

#define STATIC_ASSERT(...) static_assert((__VA_ARGS__), #__VA_ARGS__)
#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))

struct F
{
    constexpr int operator()() const
    {
        return -1;
    }

    constexpr int operator()( int x1 ) const noexcept
    {
        return x1;
    }

    constexpr int operator()( int x1, int x2 ) const
    {
        return 10*x1+x2;
    }

    constexpr int operator()( int x1, int x2, int x3 ) const noexcept
    {
        return 100*x1 + 10*x2 + x3;
    }
};

int main()
{
    {
        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F() ), -1 );
        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F(), 1 ), 1 );
        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F(), 1, 2 ), 12 );
        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F(), 1, 2, 3 ), 123 );

#if !defined(BOOST_NO_CXX14_CONSTEXPR)

        STATIC_ASSERT( boost::compat::invoke_r<void>( F() ), true );
        STATIC_ASSERT( boost::compat::invoke_r<void>( F(), 1 ), true );
        STATIC_ASSERT( boost::compat::invoke_r<void>( F(), 1, 2 ), true );
        STATIC_ASSERT( boost::compat::invoke_r<void>( F(), 1, 2, 3 ), true );

#endif
    }

    {
        constexpr F f = {};

        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f ), -1 );
        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f, 1 ), 1 );
        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f, 1, 2 ), 12 );
        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f, 1, 2, 3 ), 123 );

#if !defined(BOOST_NO_CXX14_CONSTEXPR)

        STATIC_ASSERT( boost::compat::invoke_r<void>( f ), true );
        STATIC_ASSERT( boost::compat::invoke_r<void>( f, 1 ), true );
        STATIC_ASSERT( boost::compat::invoke_r<void>( f, 1, 2 ), true );
        STATIC_ASSERT( boost::compat::invoke_r<void>( f, 1, 2, 3 ), true );

#endif
    }
}