Use StrCollection in additional places. (#16301)

1 files changed, 3 insertions, 4 deletions

diff --git a/synapse/state/v2.py b/synapse/state/v2.py
index 44c49274a9..1752f95db8 100644
--- a/synapse/state/v2.py
+++ b/synapse/state/v2.py
@@ -19,7 +19,6 @@ from typing import (
     Any,
     Awaitable,
     Callable,
-    Collection,
     Dict,
     Generator,
     Iterable,
@@ -39,7 +38,7 @@ from synapse.api.constants import EventTypes
 from synapse.api.errors import AuthError
 from synapse.api.room_versions import RoomVersion
 from synapse.events import EventBase
-from synapse.types import MutableStateMap, StateMap
+from synapse.types import MutableStateMap, StateMap, StrCollection
 
 logger = logging.getLogger(__name__)
 
@@ -56,7 +55,7 @@ class StateResolutionStore(Protocol):
     # This is usually synapse.state.StateResolutionStore, but it's replaced with a
     # TestStateResolutionStore in tests.
     def get_events(
-        self, event_ids: Collection[str], allow_rejected: bool = False
+        self, event_ids: StrCollection, allow_rejected: bool = False
     ) -> Awaitable[Dict[str, EventBase]]:
         ...
 
@@ -366,7 +365,7 @@ async def _get_auth_chain_difference(
         union = unpersisted_set_ids[0].union(*unpersisted_set_ids[1:])
         intersection = unpersisted_set_ids[0].intersection(*unpersisted_set_ids[1:])
 
-        auth_difference_unpersisted_part: Collection[str] = union - intersection
+        auth_difference_unpersisted_part: StrCollection = union - intersection
     else:
         auth_difference_unpersisted_part = ()
         state_sets_ids = [set(state_set.values()) for state_set in state_sets]