tests: use asynctest some more

Instead of hoping normal Mock will work (which does not on Python 3.8).

qubesadmin/tests/tools/qvm_backup.py

@@ -22,6 +22,7 @@ import os
 import unittest.mock as mock
 
 import asyncio
+import asynctest
 
 import qubesadmin.tests
 import qubesadmin.tests.tools
@@ -177,9 +178,11 @@ class TC_00_qvm_backup(qubesadmin.tests.QubesTestCase):
                 None)] = \
             b'0\0'
         try:
+            mock_events = asynctest.CoroutineMock()
             patch = mock.patch(
-                'qubesadmin.events.EventsDispatcher._get_events_reader')
-            mock_events = patch.start()
+                'qubesadmin.events.EventsDispatcher._get_events_reader',
+                mock_events)
+            patch.start()
             self.addCleanup(patch.stop)
             mock_events.side_effect = qubesadmin.tests.tools.MockEventsReader([
                 b'1\0\0connection-established\0\0',

qubesadmin/tests/tools/qvm_shutdown.py

@@ -18,7 +18,9 @@
 # You should have received a copy of the GNU Lesser General Public License along
 # with this program; if not, see <http://www.gnu.org/licenses/>.
 import asyncio
+import asynctest
 import unittest.mock
+
 import qubesadmin.tests
 import qubesadmin.tests.tools
 import qubesadmin.tools.qvm_shutdown
@@ -85,9 +87,11 @@ class TC_00_qvm_shutdown(qubesadmin.tests.QubesTestCase):
         loop = asyncio.new_event_loop()
         asyncio.set_event_loop(loop)
 
+        mock_events = asynctest.CoroutineMock()
         patch = unittest.mock.patch(
-            'qubesadmin.events.EventsDispatcher._get_events_reader')
-        mock_events = patch.start()
+            'qubesadmin.events.EventsDispatcher._get_events_reader',
+            mock_events)
+        patch.start()
         self.addCleanup(patch.stop)
         mock_events.side_effect = qubesadmin.tests.tools.MockEventsReader([
             b'1\0\0connection-established\0\0',
@@ -114,9 +118,11 @@ class TC_00_qvm_shutdown(qubesadmin.tests.QubesTestCase):
         loop = asyncio.new_event_loop()
         asyncio.set_event_loop(loop)
 
+        mock_events = asynctest.CoroutineMock()
         patch = unittest.mock.patch(
-            'qubesadmin.events.EventsDispatcher._get_events_reader')
-        mock_events = patch.start()
+            'qubesadmin.events.EventsDispatcher._get_events_reader',
+            mock_events)
+        patch.start()
         self.addCleanup(patch.stop)
         mock_events.side_effect = qubesadmin.tests.tools.MockEventsReader([
             b'1\0\0connection-established\0\0',
@@ -159,9 +165,11 @@ class TC_00_qvm_shutdown(qubesadmin.tests.QubesTestCase):
         loop = asyncio.new_event_loop()
         asyncio.set_event_loop(loop)
 
+        mock_events = asynctest.CoroutineMock()
         patch = unittest.mock.patch(
-            'qubesadmin.events.EventsDispatcher._get_events_reader')
-        mock_events = patch.start()
+            'qubesadmin.events.EventsDispatcher._get_events_reader',
+            mock_events)
+        patch.start()
         self.addCleanup(patch.stop)
         mock_events.side_effect = qubesadmin.tests.tools.MockEventsReader([
             b'1\0\0connection-established\0\0',