public void QueueSource_should_wait_when_buffer_is_full_and_backpressure_is_on()
{
this.AssertAllStagesStopped(() =>
{
var s = this.CreateManualProbe<int>();
var queue =
Source.Queue<int>(1, OverflowStrategy.Backpressure)
.To(Sink.FromSubscriber(s))
.Run(_materializer);
var sub = s.ExpectSubscription();
AssertSuccess(queue.OfferAsync(1));
queue.OfferAsync(2).PipeTo(TestActor);
ExpectNoMsg(_pause);
sub.Request(1);
s.ExpectNext(1);
sub.Request(1);
s.ExpectNext(2);
ExpectMsg<Enqueued>();
sub.Cancel();
}, _materializer);
}