FutureObserverLib.hpp

// -*- mode:C++; tab-width:4; c-basic-offset:4; indent-tabs-mode:nil -*-
 
#ifndef __FUTURE_OBSERVER_HPP__
#define __FUTURE_OBSERVER_HPP__
 
#include "gtest/gtest.h"
 
#include <chrono>
#include <functional>
#include <future>
#include <thread>
#include <utility>
#include <vector>
 
namespace roboticslab::test
{
 
class FutureObserver
{
public:
    virtual ~FutureObserver() = default;
 
    void shutdown()
    {
        for (auto f : futures)
        {
            if (f->valid())
            {
                f->wait();
            }
 
            delete f;
        }
    }
 
    std::future<void> & f()
    {
        auto * f = new std::future<void>;
        futures.push_back(f);
        return *f;
    }
 
    static constexpr int MILLIS = 50;
 
private:
    std::vector<std::future<void> *> futures;
};
 
class observer_timer final
{
public:
    template<typename Fn>
    observer_timer(int _milliseconds, Fn && _fn)
        : milliseconds(_milliseconds), fn(std::move(_fn))
    { }
 
    void operator()()
    {
        std::this_thread::sleep_for(std::chrono::milliseconds(milliseconds));
        ASSERT_TRUE(fn());
    }
 
private:
    int milliseconds;
    std::function<bool()> fn;
};
 
} // namespace roboticslab::test
 
#endif // __FUTURE_OBSERVER_HPP__