From a28569f79d0022cf5c749da4e271fc0e3dce17a7 Mon Sep 17 00:00:00 2001
From: Eric Eastwood <eric.eastwood@beta.gouv.fr>
Date: Tue, 28 May 2024 15:41:32 -0500
Subject: [PATCH] Add understanding of this skip

---
 synapse/handlers/sync.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index 485a13f194..b925eab385 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -1977,7 +1977,9 @@ class SyncHandler:
 
             for room_id, event in last_membership_change_by_room_id.items():
                 assert event.internal_metadata.stream_ordering
-                # Skip any events that TODO
+                # As a shortcut, skip any events that happened before we got our
+                # `get_rooms_for_user()` snapshot (any changes are already represented
+                # in that list).
                 if (
                     event.internal_metadata.stream_ordering
                     < token_before_rooms.room_key.stream