From 9ea961ae532a240fc44294734a900b8d9496aeca Mon Sep 17 00:00:00 2001
From: Bruno Windels <brunow@matrix.org>
Date: Mon, 14 Sep 2020 17:43:06 +0200
Subject: [PATCH] don't crash when we don't have a subscription anymore

---
 src/domain/ViewModel.js                               | 6 ++++++
 src/domain/session/room/timeline/TimelineViewModel.js | 4 ++++
 2 files changed, 10 insertions(+)

diff --git a/src/domain/ViewModel.js b/src/domain/ViewModel.js
index 15812f8c..7f973ad7 100644
--- a/src/domain/ViewModel.js
+++ b/src/domain/ViewModel.js
@@ -25,6 +25,7 @@ export class ViewModel extends EventEmitter {
     constructor({clock, emitChange} = {}) {
         super();
         this.disposables = null;
+        this._isDisposed = false;
         this._options = {clock, emitChange};
     }
 
@@ -43,6 +44,11 @@ export class ViewModel extends EventEmitter {
         if (this.disposables) {
             this.disposables.dispose();
         }
+        this._isDisposed = true;
+    }
+
+    get isDisposed() {
+        return this._isDisposed;
     }
 
     disposeTracked(disposable) {
diff --git a/src/domain/session/room/timeline/TimelineViewModel.js b/src/domain/session/room/timeline/TimelineViewModel.js
index 16d529cb..a4f662f6 100644
--- a/src/domain/session/room/timeline/TimelineViewModel.js
+++ b/src/domain/session/room/timeline/TimelineViewModel.js
@@ -50,6 +50,10 @@ export class TimelineViewModel extends ViewModel {
      * @return {bool} startReached if the start of the timeline was reached
      */
     async loadAtTop() {
+        if (this.isDisposed) {
+            // stop loading more, we switched room
+            return true;
+        }
         const firstTile = this._tiles.getFirst();
         if (firstTile.shape === "gap") {
             return firstTile.fill();