juanmendes

@Component({})
class NonLeakyComponent implements OnDestroy {

  private subscriptions: Subscription[];

  ngOnInit() {
    const myTimer = timer(1,1);
    this.subscriptions.push(myTimer.subscribe(
      () => console.log("timer called")
    ));

juanmendes

export class SubscriptionTracker {
    private subscriptions: Subscription[] = [];

    constructor(destroyable: OnDestroy) {
        const originalOnDestroy = destroyable.ngOnDestroy;
        destroyable.ngOnDestroy = () => {
            this.unsubscribeAll();
            originalOnDestroy.call(destroyable);
        };
    }

juanmendes

@Component({})
class NotLeakyComponent implements OnDestroy {

  private subTracker: SubscriptionTracker;

  ngOnInit() {
    const myTimer = timer(1,1);
    this.subTracker.subscribe(myTimer,
      () => console.log("timer called")
    );

juanmendes

type Constructor<T = {}> = new (...args: any[]) => T;

function SubscriptionTrackerMixin<TBase extends Constructor>(Base: TBase) {
  return class extends Base implements OnDestroy {

    private subscriptions: Subscription[]  = [];

    public subscribe<T>(
      observable: Observable<T>,
      observerOrNext?: PartialObserver<T> | ((value: T) => void),

juanmendes

@Component({})
class NonLeakyComponent extends SubscriptionTrackerMixin(Object) implements OnDestroy {

  ngOnInit() {
    const myTimer = timer(1,1);
    this.subscribe(myTimer, () => console.log("timer called"));
  }  
}