edx/edx-platform — pull request #3985 by FiloSottile (2014-06-05 01:34:55+00:00)
Title: Update diff-cover to v0.4.1 and support --compare-branch

Recent versions of diff-cover introduced support for the --compare-branch command line argument. This patch adds support for it to `rake coverage`.

`rake coverage[rev_id]` will run diff-cover against that rev, while the default `rake coverage` behavior is unchanged.