diff --git a/heat/tests/test_engine_service.py b/heat/tests/test_engine_service.py
index dd8bbe9280..500eb7cb42 100644
--- a/heat/tests/test_engine_service.py
+++ b/heat/tests/test_engine_service.py
@@ -2987,12 +2987,10 @@ class ThreadGroupManagerTest(HeatTestCase):
             self.stlock_mock.StackLock.assert_called_with(self.cnxt,
                                                           self.stack,
                                                           self.engine_id)
-            self.lock_mock.acquire.assert_called_once()
-            thm.start_with_acquired_lock.assert_called_once()
-            calls = thm.start_with_acquired_lock.call_args
-            self.assertEqual((self.stack, self.lock_mock, self.f) + self.fargs,
-                             calls[0])
-            self.assertEqual(self.fkwargs, calls[1])
+
+            thm.start_with_acquired_lock.assert_called_once_with(
+                self.stack, self.lock_mock,
+                self.f, *self.fargs, **self.fkwargs)
 
     def test_tgm_start(self):
         stack_id = 'test'
diff --git a/heat/tests/test_stack_lock.py b/heat/tests/test_stack_lock.py
index a5069bf51d..c497508666 100644
--- a/heat/tests/test_stack_lock.py
+++ b/heat/tests/test_stack_lock.py
@@ -170,17 +170,17 @@ class StackLockTest(HeatTestCase):
         slock = stack_lock.StackLock(self.context, self.stack, self.engine_id)
         try:
             with slock.thread_lock(self.stack.id):
-                db_api.stack_lock_create.assert_called_once()
+                self.assertEqual(1, db_api.stack_lock_create.call_count)
                 raise Exception
         except:
-            db_api.stack_lock_release.assert_called_once()
+            self.assertEqual(1, db_api.stack_lock_release.call_count)
 
     def test_thread_lock_context_mgr_no_exception(self):
         db_api.stack_lock_create = mock.Mock(return_value=None)
         db_api.stack_lock_release = mock.Mock(return_value=None)
         slock = stack_lock.StackLock(self.context, self.stack, self.engine_id)
         with slock.thread_lock(self.stack.id):
-            db_api.stack_lock_create.assert_called_once()
+            self.assertEqual(1, db_api.stack_lock_create.call_count)
         assert not db_api.stack_lock_release.called
 
     def test_try_thread_lock_context_mgr_exception(self):
@@ -189,17 +189,17 @@ class StackLockTest(HeatTestCase):
         slock = stack_lock.StackLock(self.context, self.stack, self.engine_id)
         try:
             with slock.try_thread_lock(self.stack.id):
-                db_api.stack_lock_create.assert_called_once()
+                self.assertEqual(1, db_api.stack_lock_create.call_count)
                 raise Exception
         except:
-            db_api.stack_lock_release.assert_called_once()
+            self.assertEqual(1, db_api.stack_lock_release.call_count)
 
     def test_try_thread_lock_context_mgr_no_exception(self):
         db_api.stack_lock_create = mock.Mock(return_value=None)
         db_api.stack_lock_release = mock.Mock(return_value=None)
         slock = stack_lock.StackLock(self.context, self.stack, self.engine_id)
         with slock.try_thread_lock(self.stack.id):
-            db_api.stack_lock_create.assert_called_once()
+            self.assertEqual(1, db_api.stack_lock_create.call_count)
         assert not db_api.stack_lock_release.called
 
     def test_try_thread_lock_context_mgr_existing_lock(self):
@@ -208,7 +208,7 @@ class StackLockTest(HeatTestCase):
         slock = stack_lock.StackLock(self.context, self.stack, self.engine_id)
         try:
             with slock.try_thread_lock(self.stack.id):
-                db_api.stack_lock_create.assert_called_once()
+                self.assertEqual(1, db_api.stack_lock_create.call_count)
                 raise Exception
         except:
             assert not db_api.stack_lock_release.called