Switch to stestr

According to Openstack summit session [1],
stestr is maintained project to which all Openstack projects should migrate.
Let's switch to stestr as other projects have already moved to it.

[1] https://etherpad.openstack.org/p/YVR-python-pti

Change-Id: Ifa7bb85e6290898c073859cbaf38f566ece2dff9

.gitignore

@@ -25,8 +25,7 @@ pip-log.txt
 # Unit test / coverage reports
 .coverage
 .tox
-.testrepository
-nosetests.xml
+.stestr/
 
 # Translations
 *.mo

.stestr.conf

@@ -0,0 +1,4 @@
+[DEFAULT]
+test_path=./instack/tests
+top_dir=./
+

.testr.conf

@@ -1,4 +0,0 @@
-[DEFAULT]
-test_command=OS_STDOUT_CAPTURE=1 OS_STDERR_CAPTURE=1 OS_TEST_TIMEOUT=60 OS_LOG_CAPTURE=1 ${PYTHON:-python} -m subunit.run discover -t ./instack ./instack $LISTOPT $IDOPTION
-test_id_option=--load-list $IDFILE
-test_list_option=--list

test-requirements.txt

@@ -8,7 +8,7 @@ fixtures>=3.0.0 # Apache-2.0/BSD
 python-subunit>=1.0.0 # Apache-2.0/BSD
 sphinx!=1.6.6,!=1.6.7,>=1.6.2 # BSD
 oslosphinx>=4.7.0 # Apache-2.0
-testrepository>=0.0.18 # Apache-2.0/BSD
+stestr>=2.0.0 # Apache-2.0
 testscenarios>=0.4 # Apache-2.0/BSD
 testtools>=2.2.0 # MIT
 mock>=2.0.0 # BSD

tox.ini

@@ -10,7 +10,7 @@ setenv =
    VIRTUAL_ENV={envdir}
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
-commands = python setup.py testr --slowest --testr-args='{posargs}'
+commands = stestr run --slowest {posargs}
 
 [testenv:pep8]
 commands = flake8
@@ -19,7 +19,13 @@ commands = flake8
 commands = {posargs}
 
 [testenv:cover]
-commands = python setup.py testr --coverage --testr-args='{posargs}'
+setenv =
+    PYTHON=coverage run --source instack --parallel-mode
+commands =
+    stestr run '{posargs}'
+    coverage combine
+    coverage html -d cover
+    coverage xml -o cover/coverage.xml
 
 [flake8]
 # H803 skipped on purpose per list discussion.