Function forkInnerZoneWithAngularBehavior

packages/core/src/zone/ng_zone.ts:426–524

(zone: NgZonePrivate)

}

function forkInnerZoneWithAngularBehavior(zone: NgZonePrivate) {
  const delayChangeDetectionForEventsDelegate = () => {
    delayChangeDetectionForEvents(zone);
  };
  const instanceId = ngZoneInstanceId++;
  zone._inner = zone._inner.fork({
    name: 'angular',
    properties: <any>{
      [isAngularZoneProperty]: true,
      [angularZoneInstanceIdProperty]: instanceId,
      [angularZoneInstanceIdProperty + instanceId]: true,
    },
    onInvokeTask: (
      delegate: ZoneDelegate,
      current: Zone,
      target: Zone,
      task: Task,
      applyThis: any,
      applyArgs: any,
    ): any => {
      // Prevent triggering change detection when the flag is detected.
      if (shouldBeIgnoredByZone(applyArgs)) {
        return delegate.invokeTask(target, task, applyThis, applyArgs);
      }

      try {
        onEnter(zone);
        return delegate.invokeTask(target, task, applyThis, applyArgs);
      } finally {
        if (
          (zone.shouldCoalesceEventChangeDetection && task.type === 'eventTask') ||
          zone.shouldCoalesceRunChangeDetection
        ) {
          delayChangeDetectionForEventsDelegate();
        }
        onLeave(zone);
      }
    },

    onInvoke: (
      delegate: ZoneDelegate,
      current: Zone,
      target: Zone,
      callback: Function,
      applyThis: any,
      applyArgs?: any[],
      source?: string,
    ): any => {
      try {
        onEnter(zone);
        return delegate.invoke(target, callback, applyThis, applyArgs, source);
      } finally {
        if (
          zone.shouldCoalesceRunChangeDetection &&
          // Do not delay change detection when the task is the scheduler's tick.
          // We need to synchronously trigger the stability logic so that the
          // zone-based scheduler can prevent a duplicate ApplicationRef.tick
          // by first checking if the scheduler tick is running. This does seem a bit roundabout,