Switch coverage tox env to stestr

We already switched the unit tests to follow the updated PTI
guidelines[1] but neglected to switch the coverage environment. Do that
now.

[1] https://governance.openstack.org/tc/reference/pti/python.html#python-test-running

Change-Id: Ie153516196f18c030ea58e76a0eac15c86169c6b

1 files changed, 8 insertions, 1 deletions

diff --git a/tox.ini b/tox.ini
index 96b843e..860a0a3 100644
--- a/tox.ini
+++ b/tox.ini
@@ -33,7 +33,14 @@ commands = bandit -r keystonemiddleware -x tests -n5
 commands = {posargs}
 
 [testenv:cover]
-commands = python setup.py testr --coverage --testr-args='{posargs}'
+setenv =
+    {[testenv]setenv}
+    PYTHON=coverage run --source keystonemiddleware --parallel-mode
+commands =
+    stestr run {posargs}
+    coverage combine
+    coverage html -d cover
+    coverage xml -o cover/coverage.xml
 
 [testenv:debug]