public void when_adding_annotation_then_can_retrieve_it()
        {
            var annotated = new AnnotatedObject();

            annotated.AddAnnotation(new FooAnnotation());

            Assert.NotNull(annotated.Annotation<FooAnnotation>());
        }
        public void when_adding_two_annotations_then_can_retrieve_one()
        {
            var annotated = new AnnotatedObject();
            var annotation = new FooAnnotation();

            annotated.AddAnnotation(annotation);
            annotated.AddAnnotation(new BarAnnotation());

            Assert.Same(annotation, annotated.Annotation<FooAnnotation>());
        }