test(latest-event): Check that we don't apply invalid edits in the latest event

crates/matrix-sdk/src/latest_events/latest_event/builder.rs

@@ -2290,6 +2290,76 @@ mod builder_tests {
         );
     }
 
+    #[async_test]
+    async fn test_remote_edit_invalid_edit() {
+        let room_id = room_id!("!r0");
+        let user_id = user_id!("@mnt_io:matrix.org");
+        let event_factory = EventFactory::new().sender(user_id).room(room_id);
+        let event_id_0 = event_id!("$ev0");
+        let event_id_1 = event_id!("$ev1");
+
+        let server = MatrixMockServer::new().await;
+        let client = server.client_builder().build().await;
+
+        // Prelude.
+        {
+            // Create the room.
+            client.base_client().get_or_create_room(room_id, RoomState::Joined);
+
+            // Initialise the event cache store.
+            client
+                .event_cache_store()
+                .lock()
+                .await
+                .expect("Could not acquire the event cache lock")
+                .as_clean()
+                .expect("Could not acquire a clean event cache lock")
+                .handle_linked_chunk_updates(
+                    LinkedChunkId::Room(room_id),
+                    vec![
+                        Update::NewItemsChunk {
+                            previous: None,
+                            new: ChunkIdentifier::new(0),
+                            next: None,
+                        },
+                        Update::PushItems {
+                            at: Position::new(ChunkIdentifier::new(0), 0),
+                            items: vec![
+                                // a text message
+                                event_factory
+                                    .text_msg("hello")
+                                    .sender(user_id!("@alice:example.org"))
+                                    .event_id(event_id_0)
+                                    .into(),
+                                // a replacement of the previous message
+                                event_factory
+                                    .text_msg("* goodbye")
+                                    .event_id(event_id_1)
+                                    .sender(user_id!("@malory:example.org"))
+                                    .edit(
+                                        event_id_0,
+                                        RoomMessageEventContent::text_plain("goodbye").into(),
+                                    )
+                                    .into(),
+                            ],
+                        },
+                    ],
+                )
+                .await
+                .unwrap();
+        }
+
+        let event_cache = client.event_cache();
+        event_cache.subscribe().unwrap();
+
+        let (room_event_cache, _) = event_cache.for_room(room_id).await.unwrap();
+
+        assert_remote_value_matches_room_message_with_body!(
+            // We get `event_id_0` because the edit `event_id_1` is invalid.
+            Builder::new_remote(&room_event_cache, LatestEventValue::None, user_id, None).await => with body = "hello"
+        );
+    }
+
     #[async_test]
     async fn test_remote_double_edit() {
         let room_id = room_id!("!r0");