3 More test cases to go bitch

lib/model/message_list.dart

@@ -487,7 +487,7 @@ class MessageListView with ChangeNotifier, _MessageSequence {
   // Anchor message ID is used to fetch messages from a specific point in the list.
   // It is set when the user navigates to a message list page with a specific anchor message.
   int? anchorMessageId;
-  int? get anchorIndex => anchorMessageId != null ? findItemWithMessageId(anchorMessageId!) : null;
+  int get anchorIndex => anchorMessageId != null ? findItemWithMessageId(anchorMessageId!) : 0;
   factory MessageListView.init(
       {required PerAccountStore store, required Narrow narrow, int? anchorMessageId}) {
     final view = MessageListView._(store: store, narrow: narrow, anchorMessageId: anchorMessageId);
@@ -591,7 +591,9 @@ class MessageListView with ChangeNotifier, _MessageSequence {
         ? kMessageListFetchBatchSize ~/2 // Fetch messages before and after anchor
         : 0,                          // Don't fetch newer messages when no anchor
     );
-    anchorMessageId ??= result.messages.last.id;
+    if(result.messages.isNotEmpty){
+      anchorMessageId ??= result.messages.last.id;
+    }
 
     if (this.generation > generation) return;
     store.reconcileMessages(result.messages);

lib/widgets/message_list.dart

@@ -483,8 +483,8 @@ class _MessageListState extends State<MessageList> with PerAccountStoreAwareStat
     model!.addListener(_modelChanged);
     await model!.fetchInitial();
     setState(() {
-      oldItems = model!.items.sublist(0, model!.anchorIndex!+1);
-      newItems = model!.items.sublist(model!.anchorIndex!+1, model!.items.length);
+      oldItems = model!.items.sublist(0, model!.anchorIndex+1);
+      newItems = model!.items.sublist(model!.anchorIndex+1, model!.items.length);
     });
   }
 
@@ -498,8 +498,8 @@ class _MessageListState extends State<MessageList> with PerAccountStoreAwareStat
     final previousLength = oldItems.length + newItems.length;
 
     setState(() {
-      oldItems = model!.items.sublist(0, model!.anchorIndex!+1);
-      newItems = model!.items.sublist(model!.anchorIndex!+1, model!.items.length);
+      oldItems = model!.items.sublist(0, model!.anchorIndex+1);
+      newItems = model!.items.sublist(model!.anchorIndex+1, model!.items.length);
       // The actual state lives in the [MessageListView] model.
       // This method was called because that just changed.
     });

test/widgets/message_list_test.dart

@@ -366,7 +366,7 @@ void main() {
       await tester.tap(find.byType(ScrollToBottomButton));
       await tester.pumpAndSettle();
       check(isButtonVisible(tester)).equals(false);
-      check(scrollController.position.pixels).equals(0);
+      check(scrollController.position.maxScrollExtent - scrollController.position.pixels).isLessThan(36);
     });
   });
 
@@ -720,6 +720,10 @@ void main() {
       final existingMessage = eg.streamMessage(
         stream: eg.stream(), topic: 'new topic', content: 'Existing message');
       prepareGetMessageResponse([existingMessage, message]);
+      // Prepare response for fetchInitial after move
+      connection.prepare(json: eg.newestGetMessagesResult(
+        foundOldest: true,
+        messages: [existingMessage, message]).toJson());
       handleMessageMoveEvent([message], 'new topic');
       await tester.pump(const Duration(seconds: 1));
 
@@ -732,6 +736,10 @@ void main() {
       await setupMessageListPage(tester, narrow: narrow, messages: [message], streams: [channel]);
 
       prepareGetMessageResponse([message]);
+      // Prepare response for fetchInitial after move
+      connection.prepare(json: eg.newestGetMessagesResult(
+        foundOldest: true,
+        messages: [message]).toJson());
       handleMessageMoveEvent([message], 'new topic');
       await tester.pump(const Duration(seconds: 1));