2 files changed, 12 insertions, 8 deletions
diff --git a/tests/replication/_base.py b/tests/replication/_base.py
index 1d4a592862..aff19d9fb3 100644
--- a/tests/replication/_base.py
+++ b/tests/replication/_base.py
@@ -266,7 +266,7 @@ class BaseMultiWorkerStreamTestCase(unittest.HomeserverTestCase):
         return resource
 
     def make_worker_hs(
-        self, worker_app: str, extra_config: dict = {}, **kwargs
+        self, worker_app: str, extra_config: Optional[dict] = None, **kwargs
     ) -> HomeServer:
         """Make a new worker HS instance, correctly connecting replcation
         stream to the master HS.
@@ -283,7 +283,7 @@ class BaseMultiWorkerStreamTestCase(unittest.HomeserverTestCase):
 
         config = self._get_worker_hs_config()
         config["worker_app"] = worker_app
-        config.update(extra_config)
+        config.update(extra_config or {})
 
         worker_hs = self.setup_test_homeserver(
             homeserver_to_use=GenericWorkerServer,
diff --git a/tests/replication/slave/storage/test_events.py b/tests/replication/slave/storage/test_events.py
index 0ceb0f935c..333374b183 100644
--- a/tests/replication/slave/storage/test_events.py
+++ b/tests/replication/slave/storage/test_events.py
@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import logging
+from typing import Iterable, Optional
 
 from canonicaljson import encode_canonical_json
 
@@ -332,15 +333,18 @@ class SlavedEventStoreTestCase(BaseSlavedStoreTestCase):
         room_id=ROOM_ID,
         type="m.room.message",
         key=None,
-        internal={},
+        internal: Optional[dict] = None,
         depth=None,
-        prev_events=[],
-        auth_events=[],
-        prev_state=[],
+        prev_events: Optional[list] = None,
+        auth_events: Optional[list] = None,
+        prev_state: Optional[list] = None,
         redacts=None,
-        push_actions=[],
+        push_actions: Iterable = frozenset(),
         **content
     ):
+        prev_events = prev_events or []
+        auth_events = auth_events or []
+        prev_state = prev_state or []
 
         if depth is None:
             depth = self.event_id
@@ -369,7 +373,7 @@ class SlavedEventStoreTestCase(BaseSlavedStoreTestCase):
         if redacts is not None:
             event_dict["redacts"] = redacts
 
-        event = make_event_from_dict(event_dict, internal_metadata_dict=internal)
+        event = make_event_from_dict(event_dict, internal_metadata_dict=internal or {})
 
         self.event_id += 1
         state_handler = self.hs.get_state_handler()