tests (xep_0272): assert the group setup call in the preparation test

tests/unit/test_plugin_xep_0272.py

@@ -102,14 +102,20 @@ class TestXEP0272:
             mock_try_to_finish_preparation.assert_not_called()
 
     def test_try_to_finish_preparation(self, host, client):
-        """try_to_finish_preparation sets done_preparing to True."""
+        """try_to_finish_preparation sets done_preparing to True and emits the signal."""
         xep_0272 = XEP_0272(host)
         room = MagicMock()
         muji_data = {"preparing_jids": set(), "to_call": set()}
 
-        with patch.object(xep_0272, "get_muji_data", return_value=muji_data):
+        # signals are synchronous (see _Bridge.send_signal): use a plain mock, not the
+        # async one of the bridge fixture
+        with (
+            patch.object(xep_0272, "get_muji_data", return_value=muji_data),
+            patch.object(host.bridge, "call_group_setup") as mock_call_group_setup,
+        ):
             xep_0272.try_to_finish_preparation(client, room, muji_data)
             assert muji_data["done_preparing"] is True
+            mock_call_group_setup.assert_called_once()
 
     @ed
     async def test_call_group_data_set(self, host, client):