Function scheduleResolveOrReject

packages/zone.js/lib/common/promise.ts:274–318

(
      promise: ZoneAwarePromise<any>,
      zone: Zone,
      chainPromise: ZoneAwarePromise<any>,
      onFulfilled?: ((value: R) => U1) | null | undefined,
      onRejected?: ((error: any) => U2) | null | undefined,
    )

    }

    function scheduleResolveOrReject<R, U1, U2>(
      promise: ZoneAwarePromise<any>,
      zone: Zone,
      chainPromise: ZoneAwarePromise<any>,
      onFulfilled?: ((value: R) => U1) | null | undefined,
      onRejected?: ((error: any) => U2) | null | undefined,
    ): void {
      clearRejectedNoCatch(promise);
      const promiseState = (promise as any)[symbolState];
      const delegate = promiseState
        ? typeof onFulfilled === 'function'
          ? onFulfilled
          : forwardResolution
        : typeof onRejected === 'function'
          ? onRejected
          : forwardRejection;
      zone.scheduleMicroTask(
        source,
        () => {
          try {
            const parentPromiseValue = (promise as any)[symbolValue];
            const isFinallyPromise =
              !!chainPromise && symbolFinally === (chainPromise as any)[symbolFinally];
            if (isFinallyPromise) {
              // if the promise is generated from finally call, keep parent promise's state and value
              (chainPromise as any)[symbolParentPromiseValue] = parentPromiseValue;
              (chainPromise as any)[symbolParentPromiseState] = promiseState;
            }
            // should not pass value to finally callback
            const value = zone.run(
              delegate,
              undefined,
              isFinallyPromise && delegate !== forwardRejection && delegate !== forwardResolution
                ? []
                : [parentPromiseValue],
            );
            resolvePromise(chainPromise, true, value);
          } catch (error) {
            // if error occurs, should always return this error
            resolvePromise(chainPromise, false, error);
          }
        },
        chainPromise as TaskData,
      );
    }

    const ZONE_AWARE_PROMISE_TO_STRING = 'function ZoneAwarePromise() { [native code] }';