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: I753f32ecf3275cf49d8c93bf648a6a26bc6da8e7

.gitignore

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

.stestr.conf

@@ -0,0 +1,3 @@
+[DEFAULT]
+test_path=./oslo_concurrency/tests/unit
+top_path=./

lower-constraints.txt

@@ -54,7 +54,7 @@ snowballstemmer==1.2.1
 Sphinx==1.6.2
 sphinxcontrib-websupport==1.0.1
 stevedore==1.20.0
-testrepository==0.0.18
+stestr==2.0.0
 testtools==2.2.0
 traceback2==1.4.0
 unittest2==1.1.0

oslo_concurrency/lockutils.py

@@ -348,7 +348,7 @@ def _lock_wrapper(argv):
     lockutils-wrapper
 
     If you run this:
-        lockutils-wrapper python setup.py testr <etc>
+        lockutils-wrapper stestr run <etc>
 
     a temporary directory will be created for all your locks and passed to all
     your tests in an environment variable. The temporary dir will be deleted

test-requirements.txt

@@ -7,6 +7,7 @@ oslotest>=3.2.0 # Apache-2.0
 coverage!=4.4,>=4.0 # Apache-2.0
 futures>=3.0.0;python_version=='2.7' or python_version=='2.6' # BSD
 fixtures>=3.0.0 # Apache-2.0/BSD
+stestr>=2.0.0 # Apache-2.0
 
 # These are needed for docs generation
 openstackdocstheme>=1.18.1 # Apache-2.0

tox.ini

@@ -10,8 +10,8 @@ deps =
  -r{toxinidir}/requirements.txt
 # We want to support both vanilla stdlib and eventlet monkey patched
 commands =
-    lockutils-wrapper python setup.py testr --slowest --testr-args='{posargs}'
-    env TEST_EVENTLET=1 lockutils-wrapper python setup.py testr --slowest --testr-args='{posargs}'
+    lockutils-wrapper stestr run --slowest {posargs}
+    env TEST_EVENTLET=1 lockutils-wrapper stestr run --slowest {posargs}
 
 [testenv:py27]
 basepython = python2.7