Function setupReadableByteStreamController

lib/internal/webstreams/readablestream.js:3468–3523

(
  stream,
  controller,
  startAlgorithm,
  pullAlgorithm,
  cancelAlgorithm,
  highWaterMark,
  autoAllocateChunkSize)

}

function setupReadableByteStreamController(
  stream,
  controller,
  startAlgorithm,
  pullAlgorithm,
  cancelAlgorithm,
  highWaterMark,
  autoAllocateChunkSize) {
  assert(stream[kState].controller === undefined);
  if (autoAllocateChunkSize !== undefined) {
    assert(NumberIsInteger(autoAllocateChunkSize));
    assert(autoAllocateChunkSize > 0);
  }
  controller[kState] = {
    byobRequest: null,
    closeRequested: false,
    pullAgain: false,
    pulling: false,
    pullFulfilled: undefined,
    pullRejected: undefined,
    started: false,
    stream,
    queue: [],
    queueTotalSize: 0,
    highWaterMark,
    pullAlgorithm,
    cancelAlgorithm,
    autoAllocateChunkSize,
    pendingPullIntos: [],
  };
  stream[kState].controller = controller;

  const startResult = startAlgorithm();

  if (startResult === null ||
      (typeof startResult !== 'object' && typeof startResult !== 'function')) {
    // See setupReadableStreamDefaultController.
    queueMicrotask(() => {
      controller[kState].started = true;
      assert(!controller[kState].pulling);
      assert(!controller[kState].pullAgain);
      readableByteStreamControllerCallPullIfNeeded(controller);
    });
    return;
  }

  PromisePrototypeThen(
    new Promise((r) => r(startResult)),
    () => {
      controller[kState].started = true;
      assert(!controller[kState].pulling);
      assert(!controller[kState].pullAgain);
      readableByteStreamControllerCallPullIfNeeded(controller);
    },
    (error) => readableByteStreamControllerError(controller, error));
}

function setupReadableByteStreamControllerFromSource(