edx/diff-cover — pull request #39 by wedaly (2013-08-15 17:05:48+00:00)
Title: Added --no-ext-diff option to `git diff` command

This should prevent diff-cover from hanging if users have configured `git diff` to use an external diff tool, as reported here: https://github.com/edx/diff-cover/issues/35

@jrbl Could you please verify that this resolves the issue with using vimdiff?