public void An_ObservableSource_must_receive_errors_from_an_observable() { this.AssertAllStagesStopped(() => { var o = new TestObservable <int>(); var s = this.CreateManualSubscriberProbe <int>(); Source.FromObservable(o) .To(Sink.FromSubscriber(s)) .Run(_materializer); var sub = s.ExpectSubscription(); sub.Request(2); var e = new Exception("hello"); o.Event(1); o.Error(e); o.Event(2); s.ExpectNext(1); s.ExpectError().ShouldBe(e); s.ExpectNoMsg(); }, _materializer); }