React 深度学习：ReactUpdateQueue

packages/react-reconciler/src/ReactUpdateQueue.js

/**
 * 创建更新
 * @param expirationTime
 * @returns {{next: null, payload: null, expirationTime: ExpirationTime, callback: null, tag: number, nextEffect: null}}
 */
export function createUpdate(expirationTime: ExpirationTime): Update<*> {
  return {
    expirationTime: expirationTime,

    tag: UpdateState,
    payload: null,
    callback: null,

    next: null,
    nextEffect: null,
  };
}