final/test/thread/futures/futures.future_error/what.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.
//
//===----------------------------------------------------------------------===//

// <future>

// class future_error

// const char* what() const throw();

#include <future>
#include <cstring>
#include <cassert>

int main()
{
    {
        std::future_error f(std::make_error_code(std::future_errc::broken_promise));
        assert(std::strcmp(f.what(), "The associated promise has been destructed prior "
                      "to the associated state becoming ready.") == 0);
    }
    {
        std::future_error f(std::make_error_code(std::future_errc::future_already_retrieved));
        assert(std::strcmp(f.what(), "The future has already been retrieved from "
                      "the promise or packaged_task.") == 0);
    }
    {
        std::future_error f(std::make_error_code(std::future_errc::promise_already_satisfied));
        assert(std::strcmp(f.what(), "The state of the promise has already been set.") == 0);
    }
    {
        std::future_error f(std::make_error_code(std::future_errc::no_state));
        assert(std::strcmp(f.what(), "Operation not permitted on an object without "
                      "an associated state.") == 0);
    }
}