Exercise fix for #190

Author: dnozay

tox.ini

@@ -25,6 +25,7 @@ deps =
 commands =
     coverage run --append setup.py test
     coverage report --omit='.tox/*'
+    python -m xmlrunner discover -p test_xmlrunner_output
     codecov -e TOXENV
     -coveralls
 passenv = CI TRAVIS_BUILD_ID TRAVIS TRAVIS_BRANCH TRAVIS_JOB_NUMBER TRAVIS_PULL_REQUEST TRAVIS_JOB_ID TRAVIS_REPO_SLUG TRAVIS_COMMIT