Return immutable objects for cachedList decorators (#16350)

1 files changed, 12 insertions, 5 deletions

diff --git a/synapse/handlers/typing.py b/synapse/handlers/typing.py

index 4b4227003d..bdefa7f26f 100644
--- a/synapse/handlers/typing.py
+++ b/synapse/handlers/typing.py
@@ -26,7 +26,14 @@ from synapse.metrics.background_process_metrics import (
 )
 from synapse.replication.tcp.streams import TypingStream
 from synapse.streams import EventSource
-from synapse.types import JsonDict, Requester, StrCollection, StreamKeyType, UserID
+from synapse.types import (
+    JsonDict,
+    JsonMapping,
+    Requester,
+    StrCollection,
+    StreamKeyType,
+    UserID,
+)
 from synapse.util.caches.stream_change_cache import StreamChangeCache
 from synapse.util.metrics import Measure
 from synapse.util.retryutils import filter_destinations_by_retry_limiter
@@ -487,7 +494,7 @@ class TypingWriterHandler(FollowerTypingHandler):
         raise Exception("Typing writer instance got typing info over replication")
 
 
-class TypingNotificationEventSource(EventSource[int, JsonDict]):
+class TypingNotificationEventSource(EventSource[int, JsonMapping]):
     def __init__(self, hs: "HomeServer"):
         self._main_store = hs.get_datastores().main
         self.clock = hs.get_clock()
@@ -497,7 +504,7 @@ class TypingNotificationEventSource(EventSource[int, JsonDict]):
         #
         self.get_typing_handler = hs.get_typing_handler
 
-    def _make_event_for(self, room_id: str) -> JsonDict:
+    def _make_event_for(self, room_id: str) -> JsonMapping:
         typing = self.get_typing_handler()._room_typing[room_id]
         return {
             "type": EduTypes.TYPING,
@@ -507,7 +514,7 @@ class TypingNotificationEventSource(EventSource[int, JsonDict]):
 
     async def get_new_events_as(
         self, from_key: int, service: ApplicationService
-    ) -> Tuple[List[JsonDict], int]:
+    ) -> Tuple[List[JsonMapping], int]:
         """Returns a set of new typing events that an appservice
         may be interested in.
 
@@ -551,7 +558,7 @@ class TypingNotificationEventSource(EventSource[int, JsonDict]):
         room_ids: Iterable[str],
         is_guest: bool,
         explicit_room_id: Optional[str] = None,
-    ) -> Tuple[List[JsonDict], int]:
+    ) -> Tuple[List[JsonMapping], int]:
         with Measure(self.clock, "typing.get_new_events"):
             from_key = int(from_key)
             handler = self.get_typing_handler()