diff --git a/tox.ini b/tox.ini
index 5d81c41a07..b06cc9c281 100644
--- a/tox.ini
+++ b/tox.ini
@@ -22,6 +22,7 @@ commands = pep8 --repeat --show-source --ignore=E125 --exclude=.venv,.tox,dist,d
 [testenv:cover]
 basepython = python2.7
 commands =
+     {envpython} run_tests.py --group=does_not_exist
      coverage erase
      python setup.py testr --coverage
      coverage run -a run_tests.py