Akka.Streams.Tests.Dsl.FlowSumSpec.A_Sum_must_propagate_an_error C# (CSharp) Method

        public void A_Sum_must_propagate_an_error()
        {
            this.AssertAllStagesStopped(() =>
            {
                var error = new TestException("test");
                var task = InputSource.Select(x =>
                {
                    if (x > 50)
                        throw error;
                    return x;
                }).RunSum((i, i1) => 0, Materializer);

                task.Invoking(t => t.Wait(TimeSpan.FromSeconds(3))).ShouldThrow<TestException>().WithMessage("test");
            }, Materializer);
        }