Function parsePullArgs

lib/internal/streams/iter/utils.js:246–271

* Parse variadic arguments for pull/pullSync. * Returns { transforms, options } * @param {Array} args * @returns {{ transforms: Array, options: object|undefined }}

(args)

 * @returns {{ transforms: Array, options: object|undefined }}
 */
function parsePullArgs(args) {
  if (args.length === 0) {
    return { __proto__: null, transforms: [], options: undefined };
  }

  let transforms;
  let options;
  const last = args[args.length - 1];
  if (isPullOptions(last)) {
    transforms = ArrayPrototypeSlice(args, 0, -1);
    options = last;
  } else {
    transforms = args;
    options = undefined;
  }

  for (let i = 0; i < transforms.length; i++) {
    if (!isTransform(transforms[i])) {
      throw new ERR_INVALID_ARG_TYPE(
        `transforms[${i}]`, ['Function', 'Object with transform()'],
        transforms[i]);
    }
  }

  return { __proto__: null, transforms, options };
}

/**
 * Validate backpressure option value.