fix: selecting empty channel

Author: szuperaz

projects/stream-chat-angular/src/lib/channel.service.spec.ts

@@ -2033,4 +2033,19 @@ describe('ChannelService', () => {
 
     expect(service.activeChannelLastReadMessageId).toBe(undefined);
   });
+
+  it('should be able to select empty channel as active channel', () => {
+    const channel = generateMockChannels()[0];
+    channel.id = 'new-empty-channel';
+    channel.state.messages = [];
+    channel.state.latestMessages = [];
+
+    service.setAsActiveChannel(channel);
+
+    const spy = jasmine.createSpy();
+    service.activeChannel$.subscribe(spy);
+
+    expect(spy).toHaveBeenCalledWith(channel);
+    expect(service.activeChannelLastReadMessageId).toBeUndefined();
+  });
 });

projects/stream-chat-angular/src/lib/channel.service.ts

@@ -422,7 +422,7 @@ export class ChannelService<
       ]?.last_read_message_id;
     if (
       channel.state.latestMessages[channel.state.latestMessages.length - 1]
-        .id === this.activeChannelLastReadMessageId
+        ?.id === this.activeChannelLastReadMessageId
     ) {
       this.activeChannelLastReadMessageId = undefined;
     }