Code review comment for lp:~michael.nelson/launchpad/distro-series-difference-model

Why are source_version and parent_source_version returning ''? I would have expected them to return None if there was no such value.

Why not implement getComments directly instead of indirecting through IDistroSeriesDifferenceCommentSource?

Your test comments say None, but test for the empty string. Please fix either the test or the comment.

Why assertIs(True, was_updated) instead of assertTrue(was_updated)? We should only care about whether the returned value evaluates to True. We should definitely not care about its identity.

Why assertIs(True, was_updated) instead of assertTrue(ds_diff.updateStatusAndType())? It is shorter, so easier to read.