Add final type hint to synapse.server. (#15035)

3 files changed, 4 insertions, 1 deletions

diff --git a/synapse/storage/_base.py b/synapse/storage/_base.py

index 41d9111019..481fec72fe 100644
--- a/synapse/storage/_base.py
+++ b/synapse/storage/_base.py
@@ -37,6 +37,8 @@ class SQLBaseStore(metaclass=ABCMeta):
     per data store (and not one per physical database).
     """
 
+    db_pool: DatabasePool
+
     def __init__(
         self,
         database: DatabasePool,
diff --git a/synapse/storage/database.py b/synapse/storage/database.py

index e20c5c5302..feaa6cdd07 100644
--- a/synapse/storage/database.py
+++ b/synapse/storage/database.py
@@ -499,6 +499,7 @@ class DatabasePool:
     """
 
     _TXN_ID = 0
+    engine: BaseDatabaseEngine
 
     def __init__(
         self,
diff --git a/synapse/storage/databases/main/events.py b/synapse/storage/databases/main/events.py

index 1536937b67..cb66376fb4 100644
--- a/synapse/storage/databases/main/events.py
+++ b/synapse/storage/databases/main/events.py
@@ -306,7 +306,7 @@ class PersistEventsStore:
 
         # The set of event_ids to return. This includes all soft-failed events
         # and their prev events.
-        existing_prevs = set()
+        existing_prevs: Set[str] = set()
 
         def _get_prevs_before_rejected_txn(
             txn: LoggingTransaction, batch: Collection[str]