Test:Use unittest.mock on Python 3

The mock module has been added to Python 3.3 as unittest.mock.
The third party mock module doesn't seem to be maintained anymore.
This is follow up of 72c501454e and
add hacking rule to avoid regression issue.

oslotest prepares mock for six in oslotest/__init__.py as follow:
six.add_move(six.MovedModule('mock', 'mock', 'unittest.mock')) and
oslo_messaging/tests/__init__.py imports oslotest before importing
test submodules to setup six.moves for mock, then "from six.moves
import mock" works well.

Note: unittest.mock also detects wrong usage of method
assert_called_once_with.

Change-Id: I3d09733789cfa2550cf47c24f2553357d36bcc0d

oslo_messaging/hacking/checks.py

@@ -20,6 +20,8 @@ import six
 oslo_namespace_imports_dot = re.compile(r"import[\s]+oslo[.][^\s]+")
 oslo_namespace_imports_from_dot = re.compile(r"from[\s]+oslo[.]")
 oslo_namespace_imports_from_root = re.compile(r"from[\s]+oslo[\s]+import[\s]+")
+mock_imports_directly = re.compile(r"import[\s]+mock")
+mock_imports_direclty_from = re.compile(r"from[\s]+mock[\s]+import[\s]+")
 
 
 def check_oslo_namespace_imports(logical_line):
@@ -40,6 +42,17 @@ def check_oslo_namespace_imports(logical_line):
         yield(0, msg)
 
 
+def check_mock_imports(logical_line):
+    if re.match(mock_imports_directly, logical_line):
+        msg = ("O324: '%s' must be used instead of '%s'.") % (
+            logical_line.replace('import mock', 'from six.moves import mock'),
+            logical_line)
+        yield(0, msg)
+    elif re.match(mock_imports_direclty_from, logical_line):
+        msg = "O324: Use mock from six.moves."
+        yield(0, msg)
+
+
 class BaseASTChecker(ast.NodeVisitor):
     """Provides a simple framework for writing AST-based checks.
 
@@ -347,3 +360,4 @@ class CheckForLoggingIssues(BaseASTChecker):
 def factory(register):
     register(CheckForLoggingIssues)
     register(check_oslo_namespace_imports)
+    register(check_mock_imports)

oslo_messaging/tests/__init__.py

@@ -16,5 +16,8 @@
 import eventlet
 eventlet.monkey_patch()
 
-# Import oslotest before importing test submodules to setup six.moves for mock
+# oslotest prepares mock for six in oslotest/__init__.py as follow:
+# six.add_move(six.MovedModule('mock', 'mock', 'unittest.mock')) and
+# oslo.messaging imports oslotest before importing test submodules to
+# setup six.moves for mock, then "from six.moves import mock" works well.
 import oslotest

oslo_messaging/tests/drivers/pika/test_message.py

@@ -16,11 +16,10 @@ import functools
 import unittest
 
 from concurrent import futures
-from mock import mock
-from mock import patch
 from oslo_serialization import jsonutils
 from oslo_utils import timeutils
 import pika
+from six.moves import mock
 
 import oslo_messaging
 from oslo_messaging._drivers.pika_driver import pika_commons as pika_drv_cmns
@@ -151,7 +150,7 @@ class RpcPikaIncomingMessageTestCase(unittest.TestCase):
         self.assertEqual("payload_value",
                          message.message.get("payload_key", None))
 
-    @patch(("oslo_messaging._drivers.pika_driver.pika_message."
+    @mock.patch(("oslo_messaging._drivers.pika_driver.pika_message."
                  "PikaOutgoingMessage.send"))
     def test_reply_for_cast_message(self, send_reply_mock):
         message = pika_drv_msg.RpcPikaIncomingMessage(
@@ -171,9 +170,9 @@ class RpcPikaIncomingMessageTestCase(unittest.TestCase):
 
         self.assertEqual(0, send_reply_mock.call_count)
 
-    @patch("oslo_messaging._drivers.pika_driver.pika_message."
+    @mock.patch("oslo_messaging._drivers.pika_driver.pika_message."
                 "RpcReplyPikaOutgoingMessage")
-    @patch("tenacity.retry")
+    @mock.patch("tenacity.retry")
     def test_positive_reply_for_call_message(self,
                                              retry_mock,
                                              outgoing_message_mock):
@@ -206,9 +205,9 @@ class RpcPikaIncomingMessageTestCase(unittest.TestCase):
             stop=mock.ANY, retry=mock.ANY, wait=mock.ANY
         )
 
-    @patch("oslo_messaging._drivers.pika_driver.pika_message."
+    @mock.patch("oslo_messaging._drivers.pika_driver.pika_message."
                 "RpcReplyPikaOutgoingMessage")
-    @patch("tenacity.retry")
+    @mock.patch("tenacity.retry")
     def test_negative_reply_for_call_message(self,
                                              retry_mock,
                                              outgoing_message_mock):
@@ -319,7 +318,7 @@ class PikaOutgoingMessageTestCase(unittest.TestCase):
         self._message = {"msg_type": 1, "msg_str": "hello"}
         self._context = {"request_id": 555, "token": "it is a token"}
 
-    @patch("oslo_serialization.jsonutils.dump_as_bytes",
+    @mock.patch("oslo_serialization.jsonutils.dump_as_bytes",
                 new=functools.partial(jsonutils.dump_as_bytes, sort_keys=True))
     def test_send_with_confirmation(self):
         message = pika_drv_msg.PikaOutgoingMessage(
@@ -363,7 +362,7 @@ class PikaOutgoingMessageTestCase(unittest.TestCase):
         self.assertEqual({'version': '1.0'}, props.headers)
         self.assertTrue(props.message_id)
 
-    @patch("oslo_serialization.jsonutils.dump_as_bytes",
+    @mock.patch("oslo_serialization.jsonutils.dump_as_bytes",
                 new=functools.partial(jsonutils.dump_as_bytes, sort_keys=True))
     def test_send_without_confirmation(self):
         message = pika_drv_msg.PikaOutgoingMessage(
@@ -421,7 +420,7 @@ class RpcPikaOutgoingMessageTestCase(unittest.TestCase):
         self._message = {"msg_type": 1, "msg_str": "hello"}
         self._context = {"request_id": 555, "token": "it is a token"}
 
-    @patch("oslo_serialization.jsonutils.dump_as_bytes",
+    @mock.patch("oslo_serialization.jsonutils.dump_as_bytes",
                 new=functools.partial(jsonutils.dump_as_bytes, sort_keys=True))
     def test_send_cast_message(self):
         message = pika_drv_msg.RpcPikaOutgoingMessage(
@@ -467,7 +466,7 @@ class RpcPikaOutgoingMessageTestCase(unittest.TestCase):
         self.assertIsNone(props.reply_to)
         self.assertTrue(props.message_id)
 
-    @patch("oslo_serialization.jsonutils.dump_as_bytes",
+    @mock.patch("oslo_serialization.jsonutils.dump_as_bytes",
                 new=functools.partial(jsonutils.dump_as_bytes, sort_keys=True))
     def test_send_call_message(self):
         message = pika_drv_msg.RpcPikaOutgoingMessage(
@@ -542,7 +541,7 @@ class RpcReplyPikaOutgoingMessageTestCase(unittest.TestCase):
 
         self._msg_id = 12345567
 
-    @patch("oslo_serialization.jsonutils.dump_as_bytes",
+    @mock.patch("oslo_serialization.jsonutils.dump_as_bytes",
                 new=functools.partial(jsonutils.dump_as_bytes, sort_keys=True))
     def test_success_message_send(self):
         message = pika_drv_msg.RpcReplyPikaOutgoingMessage(
@@ -571,8 +570,8 @@ class RpcReplyPikaOutgoingMessageTestCase(unittest.TestCase):
         self.assertIsNone(props.reply_to)
         self.assertTrue(props.message_id)
 
-    @patch("traceback.format_exception", new=lambda x, y, z: z)
-    @patch("oslo_serialization.jsonutils.dump_as_bytes",
+    @mock.patch("traceback.format_exception", new=lambda x, y, z: z)
+    @mock.patch("oslo_serialization.jsonutils.dump_as_bytes",
                 new=functools.partial(jsonutils.dump_as_bytes, sort_keys=True))
     def test_failure_message_send(self):
         failure_info = (oslo_messaging.MessagingException,

oslo_messaging/tests/drivers/pika/test_poller.py

@@ -17,7 +17,7 @@ import time
 import unittest
 
 from concurrent import futures
-import mock
+from six.moves import mock
 
 from oslo_messaging._drivers.pika_driver import pika_exceptions as pika_drv_exc
 from oslo_messaging._drivers.pika_driver import pika_poller

oslo_messaging/tests/drivers/test_impl_kafka.py

@@ -13,7 +13,7 @@
 # under the License.
 import kafka
 import kafka.errors
-import mock
+from six.moves import mock
 import testscenarios
 
 import oslo_messaging
@@ -117,7 +117,7 @@ class TestKafkaDriver(test_utils.BaseTestCase):
         self.driver.listeners.extend(listeners)
         self.driver.cleanup()
         for listener in listeners:
-            listener.close.assert_called_once()
+            listener.close.assert_called_once_with()
 
 
 class TestKafkaConnection(test_utils.BaseTestCase):

oslo_messaging/tests/drivers/zmq/test_zmq_ack_manager.py

@@ -12,7 +12,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import mock
+from six.moves import mock
 import testtools
 import time
 

oslo_messaging/tests/drivers/zmq/test_zmq_async.py

@@ -10,7 +10,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import mock
+from six.moves import mock
 import testtools
 
 from oslo_messaging._drivers.zmq_driver.poller import green_poller

oslo_messaging/tests/drivers/zmq/test_zmq_transport_url.py

@@ -12,7 +12,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import mock
+from six.moves import mock
 import testtools
 
 import oslo_messaging

oslo_messaging/tests/notify/test_impl_messaging.py

@@ -12,7 +12,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import mock
+from six.moves import mock
 
 from oslo_messaging.tests import utils as test_utils
 

oslo_messaging/tests/rpc/test_client.py

@@ -13,9 +13,8 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import mock
-
 from oslo_config import cfg
+from six.moves import mock
 import testscenarios
 
 import oslo_messaging

oslo_messaging/tests/rpc/test_server.py

@@ -17,9 +17,9 @@ import eventlet
 import threading
 
 from oslo_config import cfg
+from six.moves import mock
 import testscenarios
 
-import mock
 import oslo_messaging
 from oslo_messaging import rpc
 from oslo_messaging.rpc import server as rpc_server_module

oslo_messaging/tests/test_opts.py

@@ -12,11 +12,10 @@
 #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 #    License for the specific language governing permissions and limitations
 #    under the License.
+from six.moves import mock
 import stevedore
 import testtools
 
-import mock
-
 from oslo_messaging import server
 try:
     from oslo_messaging import opts

oslo_messaging/tests/test_transport.py

@@ -14,9 +14,9 @@
 #    under the License.
 
 import fixtures
-import mock
 from oslo_config import cfg
 import six
+from six.moves import mock
 from stevedore import driver
 import testscenarios