diff --git a/test/unit/container/test_updater.py b/test/unit/container/test_updater.py
index 507daf992a..c2ad673236 100644
--- a/test/unit/container/test_updater.py
+++ b/test/unit/container/test_updater.py
@@ -75,7 +75,8 @@ class TestContainerUpdater(unittest.TestCase):
         self.assertTrue(cu.get_account_ring() is not None)
 
     @mock.patch.object(container_updater, 'ismount')
-    def test_run_once_with_device_unmounted(self, mock_ismount):
+    @mock.patch.object(container_updater.ContainerUpdater, 'container_sweep')
+    def test_run_once_with_device_unmounted(self, mock_sweep, mock_ismount):
 
         mock_ismount.return_value = False
         cu = container_updater.ContainerUpdater({
@@ -89,9 +90,17 @@ class TestContainerUpdater(unittest.TestCase):
         })
         containers_dir = os.path.join(self.sda1, DATADIR)
         os.mkdir(containers_dir)
+        partition_dir = os.path.join(containers_dir, "a")
+        os.mkdir(partition_dir)
+
         cu.run_once()
         self.assertTrue(os.path.exists(containers_dir))  # sanity check
 
+        # only called if a partition dir exists
+        self.assertTrue(mock_sweep.called)
+
+        mock_sweep.reset_mock()
+
         cu = container_updater.ContainerUpdater({
             'devices': self.devices_dir,
             'mount_check': 'true',
@@ -107,6 +116,8 @@ class TestContainerUpdater(unittest.TestCase):
         self.assertTrue(len(log_lines) > 0)
         msg = 'sda1 is not mounted'
         self.assertEqual(log_lines[0], msg)
+        # Ensure that the container_sweep did not run
+        self.assertFalse(mock_sweep.called)
 
     def test_run_once(self):
         cu = container_updater.ContainerUpdater({