system/utest/fit/examples/utils.cpp

// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "utils.h"

// These includes are only needed for simulating the passage of time
// in a portable manner for the purpose of writing these examples.
// You do not need to include these headers just to use |fit::promise|
// or |fit::future|.
#include <chrono>
#include <thread>

namespace utils {

fit::promise<> sleep_for_a_little_while() {
    // This is a rather inefficient way to wait for time to pass but it
    // is sufficient for our examples.
    return fit::make_promise([waited = false](fit::context& context) mutable {
        if (waited)
            return;
        waited = true;
        resume_in_a_little_while(context.suspend_task());
    });
}

void resume_in_a_little_while(fit::suspended_task task) {
    std::thread([task]() mutable {
        std::this_thread::sleep_for(std::chrono::milliseconds(50));
        task.resume_task();
    }).detach();
}

} // namespace utils