Fixed #1560 and update tests to be able to run clean_spec.rb stand-alone, and fixed a typo which masked a broken test
Fixes #1560 with an exit code of 1, and makes running clean_spec.rb
By requiring digest/sha1 in spec_helper.rb, clean_spec.rb can now be
ran stand alone. I also fixed a typo which exposed a failing test.
Fixed failing test in clean_spec.rb
Thanks for the patch!