The first patch in the series is a trivial cleanup. I _thought_ (and tricked Tomi ;)) that the next one was trivial too, but now I'm not so sure.
First, I forgot to update one test, but I mostly understand (or can at least rationalize) that output. Then I had the bright idea that I should add debugging output to other tests in T050-new. In 5 cases I can't really understand the results. It seems like it takes several runs of notmuch-new to remove directory entries. Maybe this is intended, but I couldn't figure that out in a quick look.