Function parsePipeToArgs

lib/internal/streams/iter/pull.js:90–130

* Parse pipeTo/pipeToSync arguments: [...transforms, writer, options?] * @param {Array} args * @param {string} requiredMethod - 'write' for pipeTo, 'writeSync' for pipeToSync * @returns {{ transforms: Array, writer: object, options: object }}

(args, requiredMethod)

 * @returns {{ transforms: Array, writer: object, options: object }}
 */
function parsePipeToArgs(args, requiredMethod) {
  if (args.length === 0) {
    throw new ERR_INVALID_ARG_VALUE('args', args, 'pipeTo requires a writer argument');
  }

  let options;
  let writerIndex = args.length - 1;

  // Check if last arg is options
  const last = args[args.length - 1];
  if (isPullOptions(last) && !hasMethod(last, requiredMethod)) {
    options = last;
    writerIndex = args.length - 2;
  }

  if (writerIndex < 0) {
    throw new ERR_INVALID_ARG_VALUE('args', args, 'pipeTo requires a writer argument');
  }

  const writer = args[writerIndex];
  if (!hasMethod(writer, requiredMethod)) {
    throw new ERR_INVALID_ARG_TYPE(
      'writer', `object with a ${requiredMethod} method`, writer);
  }

  const transforms = ArrayPrototypeSlice(args, 0, writerIndex);
  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,
    writer,
    options,
  };
}

function canUseSyncIterablePipeToFastPath(source, transforms, signal) {
  if (signal !== undefined ||