Method allWithCallback

packages/zone.js/lib/common/promise.ts:432–494

(
        values: any,
        callback?: {
          thenCallback: (value: any) => any;
          errorCallback: (err: any) => any;
        },
      )

      }

      static allWithCallback<R>(
        values: any,
        callback?: {
          thenCallback: (value: any) => any;
          errorCallback: (err: any) => any;
        },
      ): Promise<R> {
        let resolve: (v: any) => void;
        let reject: (v: any) => void;
        let promise = new this<R>((res, rej) => {
          resolve = res;
          reject = rej;
        });

        // Start at 2 to prevent prematurely resolving if .then is called immediately.
        let unresolvedCount = 2;
        let valueIndex = 0;

        const resolvedValues: any[] = [];
        for (let value of values) {
          if (!isThenable(value)) {
            value = this.resolve(value);
          }

          const curValueIndex = valueIndex;
          try {
            value.then(
              (value: any) => {
                resolvedValues[curValueIndex] = callback ? callback.thenCallback(value) : value;
                unresolvedCount--;
                if (unresolvedCount === 0) {
                  resolve!(resolvedValues);
                }
              },
              (err: any) => {
                if (!callback) {
                  reject!(err);
                } else {
                  resolvedValues[curValueIndex] = callback.errorCallback(err);
                  unresolvedCount--;
                  if (unresolvedCount === 0) {
                    resolve!(resolvedValues);
                  }
                }
              },
            );
          } catch (thenErr) {
            reject!(thenErr);
          }

          unresolvedCount++;
          valueIndex++;
        }

        // Make the unresolvedCount zero-based again.
        unresolvedCount -= 2;

        if (unresolvedCount === 0) {