This was a clever use of unit tests to help you "pass" each lesson. I've read a bunch of tutorials on closures, but this one really helped me "get" it. Sure, it takes liberties and glosses over things... but seeing it grow right before my eyes was really helpful.
Agreed! It would have been even more helpful if the unit tests showed both the expected result and the actual result. Now I had to guess at what the problem might be (which led to me giving up on the last problem).
