coverage==3.7.1 => pass https://travis-ci.org/xmlrunner/unittest-xml-reporting/builds/62419858
coverage==4.0 => fail https://travis-ci.org/xmlrunner/unittest-xml-reporting/builds/81695238
coverage html --omit=.tox/* No source for code: '/tmp/python-build.20150204184146.6052/Python-2.7.9/Modules/pyexpat.c'.
My point is that with version 4.0 it now tries to get coverage for C extensions; which I guess it didn't in 3.7.1. Is there a simple way to ignore C extension code?