Bugbear: Add Mutable Parameter fixes (#9682)

Part of #9366

Adds in fixes for B006 and B008, both relating to mutable parameter lint errors.

Signed-off-by: Jonathan de Jong <jonathan@automatia.nl>

tests/rest/client/v1/test_rooms.py

@@ -19,6 +19,7 @@
 """Tests REST events for /rooms paths."""
 
 import json
+from typing import Iterable
 from urllib import parse as urlparse
 
 from mock import Mock
@@ -207,7 +208,9 @@ class RoomPermissionsTestCase(RoomBase):
         )
         self.assertEquals(403, channel.code, msg=channel.result["body"])
 
-    def _test_get_membership(self, room=None, members=[], expect_code=None):
+    def _test_get_membership(
+        self, room=None, members: Iterable = frozenset(), expect_code=None
+    ):
         for member in members:
             path = "/rooms/%s/state/m.room.member/%s" % (room, member)
             channel = self.make_request("GET", path)

tests/rest/client/v1/utils.py

@@ -132,7 +132,7 @@ class RestHelper:
         src: str,
         targ: str,
         membership: str,
-        extra_data: dict = {},
+        extra_data: Optional[dict] = None,
         tok: Optional[str] = None,
         expect_code: int = 200,
     ) -> None:
@@ -156,7 +156,7 @@ class RestHelper:
             path = path + "?access_token=%s" % tok
 
         data = {"membership": membership}
-        data.update(extra_data)
+        data.update(extra_data or {})
 
         channel = make_request(
             self.hs.get_reactor(),
@@ -187,7 +187,13 @@ class RestHelper:
         )
 
     def send_event(
-        self, room_id, type, content={}, txn_id=None, tok=None, expect_code=200
+        self,
+        room_id,
+        type,
+        content: Optional[dict] = None,
+        txn_id=None,
+        tok=None,
+        expect_code=200,
     ):
         if txn_id is None:
             txn_id = "m%s" % (str(time.time()))
@@ -201,7 +207,7 @@ class RestHelper:
             self.site,
             "PUT",
             path,
-            json.dumps(content).encode("utf8"),
+            json.dumps(content or {}).encode("utf8"),
         )
 
         assert (

tests/rest/client/v2_alpha/test_relations.py

@@ -16,6 +16,7 @@
 import itertools
 import json
 import urllib
+from typing import Optional
 
 from synapse.api.constants import EventTypes, RelationTypes
 from synapse.rest import admin
@@ -681,7 +682,7 @@ class RelationsTestCase(unittest.HomeserverTestCase):
         relation_type,
         event_type,
         key=None,
-        content={},
+        content: Optional[dict] = None,
         access_token=None,
         parent_id=None,
     ):
@@ -713,7 +714,7 @@ class RelationsTestCase(unittest.HomeserverTestCase):
             "POST",
             "/_matrix/client/unstable/rooms/%s/send_relation/%s/%s/%s%s"
             % (self.room, original_id, relation_type, event_type, query),
-            json.dumps(content).encode("utf-8"),
+            json.dumps(content or {}).encode("utf-8"),
             access_token=access_token,
         )
         return channel