Comment by lcall

At least sometimes, it really helps for a test to say WHY it is done that way. I had a case where I needed to change some existing code, and all the unit tests passed but one. The author was unavailable. It was very unclear whether I should change the test. I asked around. I was about to commit the changes to the code and test when someone came back from vacation and helpfully explained. I hope I added a useful comment.