测试 Rx 中的延迟

Testing delays in Rx

我正在尝试弄清楚如何测试以下函数,该函数在 Observable.ObserveOn.

的内部队列周围添加了监控
public IObservable<T> MonitorBuffer<T>(IObservable<T> source, Action<int> monitor, TimeSpan interval, IScheduler scheduler)
{
    return Observable.Create<T>(ob =>
    {
        int count = 0;

        return new CompositeDisposable(source
            .Do(_ => Interlocked.Increment(ref count))
            .ObserveOn(scheduler)
            .Do(_ => Interlocked.Decrement(ref count))
            .Subscribe(ob),
            Observable.Interval(interval, scheduler).Select(_ => count).DistinctUntilChanged().Subscribe(monitor)
        );
    });
}

我设想的是这样的:

var ts = new TestScheduler();
var input = Enumerable.Range(1, 8).Select(i => OnNext(i * 10, i)).ToArray();
var hot = ts.CreateHotObservable(input);
var observer = ts.CreateObserver<int>();
var log = new Subject<int>();
var monitor = ts.CreateObserver<int>();
var ticks = TimeSpan.FromTicks(5);
var buffered = MonitorBuffer(hot, log.OnNext, ticks, ts);
log.Subscribe(monitor);

buffered.Do(x => { /*if(x == 3) Introduce delay here */}).Subscribe(observer);

ts.AdvanceTo(100);
observer.Messages.AssertEqual(...);
monitor.Messages.AssertEqual(...);

问题是,我可以在 Do 中输入什么来获得临时下游延迟的预期效果。

我正在寻找类似这样的结果:

//time:    0--------10--------20--------30--------40--------50--------60--------70--------
//source:  ---------1---------2---------3---------4---------5---------6---------7---------
//output:  ---------1---------2-----------------------------345-------6---------7---------
//log:     ----0-------------------------1---------2---------2----0-----------------------

(注意:前段时间问了一个similar question,但不是很清楚,现在完全重写有点晚了)。

我想我已经搞定了...

秘密是有两个可以独立推进的调度器。

基于问题中的测试代码:

var inputscheduler = new TestScheduler();
(...)

//different scheduler for buffer/observeOn
var bufferScheduler = new TestScheduler();
var buffered = MonitorBuffer(hot, log.OnNext, ticks, bufferScheduler);
log.Subscribe(monitor);
buffered.Subscribe(observer);

//instead of inserting something downstream, use scheduler advances
for (int i = 3; i < 80; i++)
{
    inputscheduler.AdvanceTo(i);
    if (i < 25|| i > 45) bufferscheduler.AdvanceTo(i);
}

observer.Messages.AssertEqual(...);
monitor.Messages.AssertEqual(...);