Akka.Streams.Tests.Dsl.SourceSpec.Maybe_Source_must_complete_materialized_future_with_None_when_stream_cancels C# (CSharp) Method

        public void Maybe_Source_must_complete_materialized_future_with_None_when_stream_cancels()
        {
            this.AssertAllStagesStopped(() =>
            {
                var neverSource = Source.Maybe<object>();
                var pubSink = Sink.AsPublisher<object>(false);

                var t = neverSource.ToMaterialized(pubSink, Keep.Both).Run(Materializer);
                var f = t.Item1;
                var neverPub = t.Item2;

                var c = TestSubscriber.CreateManualProbe<object>(this);
                neverPub.Subscribe(c);
                var subs = c.ExpectSubscription();

                subs.Request(1000);
                c.ExpectNoMsg(TimeSpan.FromMilliseconds(300));

                subs.Cancel();
                f.Task.Wait(500).Should().BeTrue();
                f.Task.Result.Should().Be(null);
            }, Materializer);
        }