From 45409428e6b4105d23fa8aae1f0db9739f3e27f6 Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Sun, 6 Dec 2020 14:42:34 -0800
Subject: [PATCH] modules/client/sync/rooms: Assertions for membership query on
 membership event.

---
 modules/client/sync/rooms.cc | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/modules/client/sync/rooms.cc b/modules/client/sync/rooms.cc
index 562edef81..5e5d39700 100644
--- a/modules/client/sync/rooms.cc
+++ b/modules/client/sync/rooms.cc
@@ -59,7 +59,8 @@ ircd::m::sync::rooms_linear(data &data)
 	{
 		json::get<"room_id"_>(*data.event)?
 			m::membership(membuf, room, data.user):
-			string_view{}
+
+		string_view{}
 	};
 
 	const scope_restore their_membership
@@ -67,6 +68,23 @@ ircd::m::sync::rooms_linear(data &data)
 		data.membership, membership
 	};
 
+	const bool is_own_membership
+	{
+		json::get<"room_id"_>(*data.event)
+		&& json::get<"type"_>(*data.event) == "m.room.member"
+		&& json::get<"state_key"_>(*data.event) == data.user.user_id
+	};
+
+	const bool is_own_join
+	{
+		is_own_membership
+		&& membership == "join"
+	};
+
+	//assert(!is_own_join || m::membership(*data.event) == "join");
+	assert(!is_own_join || !!m::membership(membuf, room, data.user));
+	assert(is_own_join || !json::get<"room_id"_>(*data.event) || m::exists(room));
+
 	if(should_ignore(data))
 		return false;