NgZone

Source

NgZone({enableLongStackTrace: false}) {
  this._zoneImpl = new NgZoneImpl(
      trace: enableLongStackTrace,
      onEnter: () {
        // console.log('ZONE.enter', this._nesting, this._isStable);
        this._nesting++;
        if (this._isStable) {
          this._isStable = false;
          this._onUnstable.emit(null);
        }
      },
      onLeave: () {
        this._nesting--;
        // console.log('ZONE.leave', this._nesting, this._isStable);
        this._checkStable();
      },
      setMicrotask: (bool hasMicrotasks) {
        this._hasPendingMicrotasks = hasMicrotasks;
        this._checkStable();
      },
      setMacrotask: (bool hasMacrotasks) {
        this._hasPendingMacrotasks = hasMacrotasks;
      },
      onError: (NgZoneError error) => this._onErrorEvents.emit(error));
}