Add cover CI job and tox env

Change-Id: Idf6011265e5674fc0016771341f65fa2037cf510

.coveragerc

@@ -0,0 +1,7 @@
+[run]
+branch = True
+source = tobiko
+omit = tobiko/tests/*
+
+[report]
+ignore_errors = True

.gitignore

@@ -5,8 +5,9 @@
 *.log
 
 # Hidden files
+.coverage
+.coverage.*
 .eggs
-.coverage*
 .stestr
 .test
 .testrepository

tox.ini

@@ -43,6 +43,28 @@ setenv =
 commands = {[base]commands}
 
 
+[testenv:cover]
+
+basepython = python3
+
+setenv =
+    {[testenv]setenv}
+    PYTHON=coverage run --parallel-mode
+
+commands =
+    find . -type f -name ".coverage.*" -delete
+    coverage erase
+    stestr run --no-subunit-trace --black-regex "{env:OS_BLACK_REGEX:}" {posargs}
+    coverage combine
+    coverage html -d cover
+    coverage xml -o cover/coverage.xml
+    coverage report --fail-under=70 --skip-covered
+    find . -type f -name ".coverage.*" -delete
+
+whitelist_externals=
+    find
+
+
 # --- static analisys environments -------------------------------------------
 
 [testenv:pep8]

zuul.d/project.yaml

@@ -12,6 +12,7 @@
         - openstack-tox-py36
         - openstack-tox-py37
         - openstack-tox-py27
+        - openstack-tox-cover
         - tobiko-devstack-neutron-centos-7
         - tobiko-devstack-neutron-centos-7-queens
         - tobiko-devstack-neutron-centos-7-rocky