At Plone we have a distribution to do code analysis: plone.recipe.codeanalysis
I made a pull request for it: https://github.com/plone/plone.recipe.codeanalysis/pull/125
But surprisingly this pull request lowers the test coverage: https://coveralls.io/builds/2679558
Given the changes seems that coverage does not count doctest tests as part of the coverage. Is that a known issue?