Fix the mocking mess

Our tests' mocking is a little messy, we have tests that start a mocking
but don't stop it, others try to stop it but use a mock object instead
of a patcher object, so they don't stop it, and we keep using stopall to
stop the patchings instead of individual stops, and we've seen in Cinder
that this can be problematic.

This patch fixes these issue, most of them just by using base TestCase
mock_object method, and some calling the right stop method (ie:
VolumeEncryptorTestCase).

Change-Id: I545abfa8749e778e923c37e0b908efc578f70619

os_brick/tests/base.py

@@ -25,9 +25,10 @@ from oslo_utils import strutils
 
 
 class TestCase(testtools.TestCase):
-
     """Test case base class for all unit tests."""
 
+    SENTINEL = object()
+
     def setUp(self):
         """Run before each test method to initialize test environment."""
         super(TestCase, self).setUp()
@@ -82,18 +83,19 @@ class TestCase(testtools.TestCase):
         log_root = logging.getLogger(None).logger
         log_root.setLevel(level)
 
-    def mock_object(self, obj, attr_name, new_attr=None, **kwargs):
+    def mock_object(self, obj, attr_name, new_attr=SENTINEL, **kwargs):
         """Use python mock to mock an object attribute
 
         Mocks the specified objects attribute with the given value.
         Automatically performs 'addCleanup' for the mock.
-
         """
-        if not new_attr:
-            new_attr = mock.Mock()
-        patcher = mock.patch.object(obj, attr_name, new_attr, **kwargs)
-        patcher.start()
+        args = [obj, attr_name]
+        if new_attr is not self.SENTINEL:
+            args.append(new_attr)
+        patcher = mock.patch.object(*args, **kwargs)
+        mocked = patcher.start()
         self.addCleanup(patcher.stop)
+        return mocked
 
     # Useful assertions
     def assertDictMatch(self, d1, d2, approx_equal=False, tolerance=0.001):

os_brick/tests/encryptors/test_base.py

@@ -36,9 +36,9 @@ class VolumeEncryptorTestCase(base.TestCase):
                 ":volume-fake_uuid-lun-1",
             },
         }
-        self.mock_execute = (
-            mock.patch("os_brick.privileged.rootwrap.execute").start())
-        self.addCleanup(self.mock_execute.stop)
+        patcher = mock.patch("os_brick.privileged.rootwrap.execute")
+        self.mock_execute = patcher.start()
+        self.addCleanup(patcher.stop)
         _hex = codecs.getdecoder("hex_codec")('0' * 32)[0]
         self.encryption_key = array.array('B', _hex).tolist()
         self.root_helper = None

os_brick/tests/initiator/connectors/test_aoe.py

@@ -52,9 +52,8 @@ class AoEConnectorTestCase(test_connector.ConnectorTestCase):
         self.connector = aoe.AoEConnector('sudo')
         self.connection_properties = {'target_shelf': 'fake_shelf',
                                       'target_lun': 'fake_lun'}
-        mock.patch.object(loopingcall, 'FixedIntervalLoopingCall',
-                          FakeFixedIntervalLoopingCall).start()
-        self.addCleanup(mock.patch.stopall)
+        self.mock_object(loopingcall, 'FixedIntervalLoopingCall',
+                         FakeFixedIntervalLoopingCall)
 
     def test_get_search_path(self):
         expected = "/dev/etherd"

os_brick/tests/initiator/connectors/test_disco.py

@@ -12,7 +12,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 import glob
-import mock
 import os
 
 from os_brick import exception
@@ -54,14 +53,11 @@ class DISCOConnectorTestCase(test_connector.ConnectorTestCase):
         self.request_status = 'success'
 
         # Patch the request and os calls to fake versions
-        mock.patch.object(disco.DISCOConnector,
-                          '_send_disco_vol_cmd',
-                          self.perform_disco_request).start()
-        mock.patch.object(os.path,
-                          'exists', self.is_volume_attached).start()
-        mock.patch.object(glob,
-                          'glob', self.list_disco_volume).start()
-        self.addCleanup(mock.patch.stopall)
+        self.mock_object(disco.DISCOConnector,
+                         '_send_disco_vol_cmd',
+                         self.perform_disco_request)
+        self.mock_object(os.path, 'exists', self.is_volume_attached)
+        self.mock_object(glob, 'glob', self.list_disco_volume)
 
         # The actual DISCO connector
         self.connector = disco.DISCOConnector(

os_brick/tests/initiator/connectors/test_iscsi.py

@@ -37,9 +37,8 @@ class ISCSIConnectorTestCase(test_connector.ConnectorTestCase):
         self.connector_with_multipath = iscsi.ISCSIConnector(
             None, execute=self.fake_execute, use_multipath=True)
 
-        mock.patch.object(self.connector._linuxscsi, 'get_name_from_path',
-                          return_value="/dev/sdb").start()
-        self.addCleanup(mock.patch.stopall)
+        self.mock_object(self.connector._linuxscsi, 'get_name_from_path',
+                         return_value="/dev/sdb")
         self._fake_iqn = 'iqn.1234-56.foo.bar:01:23456789abc'
 
     def generate_device(self, location, iqn, transport=None, lun=1):

os_brick/tests/initiator/connectors/test_scaleio.py

@@ -78,15 +78,11 @@ class ScaleIOConnectorTestCase(test_connector.ConnectorTestCase):
         ), status_code=404)
 
         # Patch the request and os calls to fake versions
-        mock.patch.object(
-            requests, 'get', self.handle_scaleio_request).start()
-        mock.patch.object(
-            requests, 'post', self.handle_scaleio_request).start()
-        mock.patch.object(os.path, 'isdir', return_value=True).start()
-        mock.patch.object(
-            os, 'listdir', return_value=["emc-vol-{}".format(self.vol['id'])]
-        ).start()
-        self.addCleanup(mock.patch.stopall)
+        self.mock_object(requests, 'get', self.handle_scaleio_request)
+        self.mock_object(requests, 'post', self.handle_scaleio_request)
+        self.mock_object(os.path, 'isdir', return_value=True)
+        self.mock_object(os, 'listdir',
+                         return_value=["emc-vol-{}".format(self.vol['id'])])
 
         # The actual ScaleIO connector
         self.connector = scaleio.ScaleIOConnector(
@@ -239,9 +235,7 @@ class ScaleIOConnectorTestCase(test_connector.ConnectorTestCase):
     @mock.patch('time.sleep')
     def test_error_path_not_found(self, sleep_mock):
         """Timeout waiting for volume to map to local file system"""
-        mock.patch.object(
-            os, 'listdir', return_value=["emc-vol-no-volume"]
-        ).start()
+        self.mock_object(os, 'listdir', return_value=["emc-vol-no-volume"])
         self.assertRaises(exception.BrickException, self.test_connect_volume)
         self.assertTrue(sleep_mock.called)
 

os_brick/tests/initiator/test_linuxfc.py

@@ -26,8 +26,7 @@ class LinuxFCTestCase(base.TestCase):
         super(LinuxFCTestCase, self).setUp()
         self.cmds = []
 
-        mock.patch.object(os.path, 'exists', return_value=True).start()
-        self.addCleanup(mock.patch.stopall)
+        self.mock_object(os.path, 'exists', return_value=True)
         self.lfc = linuxfc.LinuxFibreChannel(None, execute=self.fake_execute)
 
     def fake_execute(self, *cmd, **kwargs):

os_brick/tests/initiator/test_linuxscsi.py

@@ -31,9 +31,8 @@ class LinuxSCSITestCase(base.TestCase):
     def setUp(self):
         super(LinuxSCSITestCase, self).setUp()
         self.cmds = []
-        mock.patch.object(os.path, 'realpath', return_value='/dev/sdc').start()
-        mock.patch.object(os, 'stat', returns=os.stat(__file__)).start()
-        self.addCleanup(mock.patch.stopall)
+        self.mock_object(os.path, 'realpath', return_value='/dev/sdc')
+        self.mock_object(os, 'stat', returns=os.stat(__file__))
         self.linuxscsi = linuxscsi.LinuxSCSI(None, execute=self.fake_execute)
 
     def fake_execute(self, *cmd, **kwargs):

os_brick/tests/remotefs/test_remotefs.py

@@ -28,7 +28,7 @@ class RemoteFsClientTestCase(base.TestCase):
 
     def setUp(self):
         super(RemoteFsClientTestCase, self).setUp()
-        self.mock_execute = mock.patch.object(priv_rootwrap, 'execute').start()
+        self.mock_execute = self.mock_object(priv_rootwrap, 'execute')
 
     @mock.patch.object(remotefs.RemoteFsClient, '_read_mounts',
                        return_value=[])