Plus a test. I didn't notice that Douglas Six did basically the same thing in another PR (this was a re-do of an earlier PR which didn't quite do what we'd like). So since I already had it done and had a test, I closed that PR (#163) and added him to the author list. Also - repository.count() raises a NoSuchElementException after you delete all the documents. That seems like a bug, but we will deal with that separately.