public void InputIsAddedAsDependency()
        {
            var input = 1.AsPipelineConstant();
            var sut   = new PassivePipelineStage <int>(input);

            PipelineAssert.DependentOn(sut, input);
        }
        public void PassiveStageIsNeverInvalidated()
        {
            var assignable = new AssignablePipelineStage <int>("", 10);
            var passive    = new PassivePipelineStage <int>(assignable);
            var test       = passive.AttachTestStage();

            assignable.SetValue(11);
            test.AssertInvalidations(0);
        }