rename get_prev_events_for_room to get_prev_events_and_hashes_for_room

... to make way for a new method which just returns the event ids

synapse/handlers/message.py

@@ -740,7 +740,7 @@ class EventCreationHandler(object):
                 % (len(prev_events_and_hashes),)
             )
         else:
-            prev_events_and_hashes = yield self.store.get_prev_events_for_room(
+            prev_events_and_hashes = yield self.store.get_prev_events_and_hashes_for_room(
                 builder.room_id
             )
 
@@ -1042,7 +1042,9 @@ class EventCreationHandler(object):
             # For each room we need to find a joined member we can use to send
             # the dummy event with.
 
-            prev_events_and_hashes = yield self.store.get_prev_events_for_room(room_id)
+            prev_events_and_hashes = yield self.store.get_prev_events_and_hashes_for_room(
+                room_id
+            )
 
             latest_event_ids = (event_id for (event_id, _, _) in prev_events_and_hashes)
 

synapse/handlers/room_member.py

@@ -370,7 +370,9 @@ class RoomMemberHandler(object):
             if block_invite:
                 raise SynapseError(403, "Invites have been disabled on this server")
 
-        prev_events_and_hashes = yield self.store.get_prev_events_for_room(room_id)
+        prev_events_and_hashes = yield self.store.get_prev_events_and_hashes_for_room(
+            room_id
+        )
         latest_event_ids = (event_id for (event_id, _, _) in prev_events_and_hashes)
 
         current_state_ids = yield self.state_handler.get_current_state_ids(

synapse/storage/data_stores/main/event_federation.py

@@ -149,9 +149,10 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
         )
 
     @defer.inlineCallbacks
-    def get_prev_events_for_room(self, room_id):
+    def get_prev_events_and_hashes_for_room(self, room_id):
         """
-        Gets a subset of the current forward extremities in the given room.
+        Gets a subset of the current forward extremities in the given room,
+        along with their depths and hashes.
 
         Limits the result to 10 extremities, so that we can avoid creating
         events which refer to hundreds of prev_events.

tests/storage/test_event_federation.py

@@ -26,7 +26,7 @@ class EventFederationWorkerStoreTestCase(tests.unittest.TestCase):
         self.store = hs.get_datastore()
 
     @defer.inlineCallbacks
-    def test_get_prev_events_for_room(self):
+    def test_get_prev_events_and_hashes_for_room(self):
         room_id = "@ROOM:local"
 
         # add a bunch of events and hashes to act as forward extremities
@@ -64,7 +64,7 @@ class EventFederationWorkerStoreTestCase(tests.unittest.TestCase):
             yield self.store.db.runInteraction("insert", insert_event, i)
 
         # this should get the last five and five others
-        r = yield self.store.get_prev_events_for_room(room_id)
+        r = yield self.store.get_prev_events_and_hashes_for_room(room_id)
         self.assertEqual(10, len(r))
         for i in range(0, 5):
             el = r[i]