leaf/test/on_error_defer_nested_success_result_test.cpp

// Copyright 2018-2024 Emil Dotchevski and Reverge Studios, Inc.
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

#ifdef BOOST_LEAF_TEST_SINGLE_HEADER
#   include "leaf.hpp"
#else
#   include <boost/leaf/on_error.hpp>
#   include <boost/leaf/handle_errors.hpp>
#   include <boost/leaf/result.hpp>
#endif

#include "lightweight_test.hpp"

namespace leaf = boost::leaf;

struct info { int value; };

leaf::result<void> g1()
{
    auto load = leaf::on_error( [] { return info{1}; } );
    return { };
}

leaf::result<void> g2()
{
    return leaf::new_error();
}

leaf::result<void> f()
{
    auto load = leaf::on_error( [] { return info{2}; } );
    BOOST_LEAF_CHECK(g1());
    return g2();
}

int main()
{
    int r = leaf::try_handle_all(
        []() -> leaf::result<int>
        {
            BOOST_LEAF_CHECK(f());
            return 1;
        },
        []( info x )
        {
            BOOST_TEST_EQ(x.value, 2);
            return 2;
        },
        []
        {
            return 3;
         } );
    BOOST_TEST_EQ(r, 2);

    return boost::report_errors();
}