private IEnumerable <ITagSpan <ClassificationTag> > GetTags(string text)
        {
            var buffer = new FakeTextBuffer(text);
            var tagger = new TemplateClassificationTagger(buffer, this.registry);
            var spans  = new NormalizedSnapshotSpanCollection(new SnapshotSpan(buffer.CurrentSnapshot, 0, buffer.CurrentSnapshot.Length));

            return(tagger.GetTags(spans));
        }