public void Reverse_Arrows_in_the_GraphDsl_must_fail_towards_already_full_UniformFanInShape()
{
var task = RunnableGraph.FromGraph(GraphDsl.Create(Sink, (b, s) =>
{
var f = b.Add(new Merge<int, int>(2));
var src = b.Add(Source);
b.From(Streams.Dsl.Source.Empty<int>().MapMaterializedValue(_ => MaterializedValue)).To(f);
b.From(src).To(f);
b.Invoking(builder => builder.To(s).Via(f).From(src))
.ShouldThrow<ArgumentException>()
.WithMessage("No more inlets on junction");
return ClosedShape.Instance;
})).Run(Materializer);
task.Wait(TimeSpan.FromSeconds(1)).Should().BeTrue();
task.Result.ShouldAllBeEquivalentTo(new[] { 1, 2, 3 });
}