title: ngFor not re-rendering components when array changes
body: <pre><code>@Component({
    selector: 'app-comment-section',
    templateUrl: './comment-section.component.html',
    styleUrls: ['./comment-section.component.css']
  })
  export class CommentSectionComponent implements OnInit, OnDestroy {
  
    @Input()
    private commentable: Commentable;
    private commentRoom;
    private comments: Comment[] = [];
    private onNew: Subscription;
    private onDelete: Subscription;
  
    constructor(private service: CommentingService, private http: HttpClient) { }
  
    ngOnInit() {
      this.commentRoom = this.service.joinCommentsRoom(this.commentable.uuid);
  
      this.http.get&lt;CommentsResponse&gt;(this.commentable.url).subscribe(res =&gt; {
        this.comments = res.comments.rows;
      });
  
      this.onNew = this.commentRoom.newComment$.subscribe((comment) =&gt; {
        this.comments.push(comment);
      })
  
      this.onDelete = this.commentRoom.deletedComment$.subscribe((uuid) =&gt; {
        console.log('Comment deleted...')
        this.comments = this.comments.filter(comment =&gt; {
          return comment.uuid != uuid;
        });
      })
  
    }
  
    ngOnDestroy() {
      this.onNew.unsubscribe();
      this.onDelete.unsubscribe();
      this.commentRoom.reconnect.unsubscribe();
    }
  
  }
  </code></pre>
  
  <p>I have a comment section, that is using a commenting service to get observables that emit new and deleted comments. 
  Everything seems to work, except that the view doesn't re-render when this.comments is updated as a comment is created or deleted. I can see that the values are emitted with the console.log().</p>
  
  <p>This is what the ngFor looks like in the view:</p>
  
  <pre><code>&lt;app-comment class="comment" *ngFor="let entity of comments" [entity]="entity"&gt;&lt;/app-comment&gt;
  </code></pre>
  
  <p>Is there something I'm doing wrong that is causing the view to not update when the array changes?</p>
  
  <p>Kind regards,
  Axel</p>