Class _ZoneDelegate

packages/zone.js/lib/zone-impl.ts:1124–1388

  };

  class _ZoneDelegate implements ZoneDelegate {
    public get zone(): Zone {
      return this._zone;
    }
    private _zone: ZoneImpl;

    private _taskCounts: {[key in TaskType]: number} = {
      'microTask': 0,
      'macroTask': 0,
      'eventTask': 0,
    };

    private _forkDlgt: _ZoneDelegate | null;
    private _forkZS: ZoneSpec | null;
    private _forkCurrZone: Zone | null;

    private _interceptDlgt: _ZoneDelegate | null;
    private _interceptZS: ZoneSpec | null;
    private _interceptCurrZone: Zone | null;

    private _invokeDlgt: _ZoneDelegate | null;
    private _invokeZS: ZoneSpec | null;
    private _invokeCurrZone: ZoneImpl | null;

    private _handleErrorDlgt: _ZoneDelegate | null;
    private _handleErrorZS: ZoneSpec | null;
    private _handleErrorCurrZone: ZoneImpl | null;

    private _scheduleTaskDlgt: _ZoneDelegate | null;
    private _scheduleTaskZS: ZoneSpec | null;
    private _scheduleTaskCurrZone: ZoneImpl | null;

    private _invokeTaskDlgt: _ZoneDelegate | null;
    private _invokeTaskZS: ZoneSpec | null;
    private _invokeTaskCurrZone: ZoneImpl | null;

    private _cancelTaskDlgt: _ZoneDelegate | null;
    private _cancelTaskZS: ZoneSpec | null;
    private _cancelTaskCurrZone: ZoneImpl | null;

    private _hasTaskDlgt: _ZoneDelegate | null;
    private _hasTaskDlgtOwner: _ZoneDelegate | null;
    private _hasTaskZS: ZoneSpec | null;
    private _hasTaskCurrZone: ZoneImpl | null;

    constructor(zone: Zone, parentDelegate: _ZoneDelegate | null, zoneSpec: ZoneSpec | null) {
      this._zone = zone as ZoneImpl;

      this._forkZS = zoneSpec && (zoneSpec && zoneSpec.onFork ? zoneSpec : parentDelegate!._forkZS);
      this._forkDlgt = zoneSpec && (zoneSpec.onFork ? parentDelegate : parentDelegate!._forkDlgt);
      this._forkCurrZone =
        zoneSpec && (zoneSpec.onFork ? this._zone : parentDelegate!._forkCurrZone);

      this._interceptZS =
        zoneSpec && (zoneSpec.onIntercept ? zoneSpec : parentDelegate!._interceptZS);
      this._interceptDlgt =
        zoneSpec && (zoneSpec.onIntercept ? parentDelegate : parentDelegate!._interceptDlgt);
      this._interceptCurrZone =