I noticed that code coverage wasn't showing in Differential for
some repositories that we are using with Phabricator.
arc unit would should unit test coverage, but the paths were messy
(for example, .//foo/bar.py instead of foo/bar.py). As a result,
the code coverage info wasn't recognised as being for the correct
module.
I'm not sure why this logic is the way that it is... perhaps this is to
do with an older version of nose (I am using v1.3.0).