Fix showing events which were replied to and then redacted

src/components/views/elements/ReplyThread.js

@@ -176,6 +176,9 @@ export default class ReplyThread extends React.Component {
     componentWillMount() {
         this.unmounted = false;
         this.room = this.context.matrixClient.getRoom(this.props.parentEv.getRoomId());
+        this.room.on("Room.redaction", this.onRoomRedaction);
+        // same event handler as Room.redaction as for both we just do forceUpdate
+        this.room.on("Room.redactionCancelled", this.onRoomRedaction);
         this.initialize();
     }
 
@@ -185,7 +188,19 @@ export default class ReplyThread extends React.Component {
 
     componentWillUnmount() {
         this.unmounted = true;
+        if (this.room) {
+            this.room.removeListener("Room.redaction", this.onRoomRedaction);
+            this.room.removeListener("Room.redactionCancelled", this.onRoomRedaction);
         }
+    }
+
+    onRoomRedaction = (ev, room) => {
+        if (this.unmounted) return;
+
+        // we could skip an update if the event isn't in our timeline,
+        // but that's probably an early optimisation.
+        this.forceUpdate();
+    };
 
     async initialize() {
         const {parentEv} = this.props;
@@ -298,10 +313,12 @@ export default class ReplyThread extends React.Component {
 
             return <blockquote className="mx_ReplyThread" key={ev.getId()}>
                 { dateSep }
-                <EventTile mxEvent={ev}
+                <EventTile
+                    mxEvent={ev}
                     tileShape="reply"
                     onHeightChanged={this.props.onHeightChanged}
                     permalinkCreator={this.props.permalinkCreator}
+                    isRedacted={ev.isRedacted()}
                     isTwelveHour={SettingsStore.getValue("showTwelveHourTimestamps")} />
             </blockquote>;
         });