2.实现一个 promise 超时自动 reject

const p1 = new Promise((resolve, reject) => {
  let test = fetch("http://www.rushmc.top/api/dynamicState/select/all")
    .then((response) => response.json()) //解析为可读数据
    .then((data) => console.log(data));
  //执行结果是 resolve就调用then方法
});
const p2 = new Promise((resolve, reject) => {
  setTimeout(() => {
    reject("err啦");
  }, 2000);
});
Promise.race([p1, p2])
  .then((res) => {
    console.log(res);
  })
  .catch((err) => {
    console.log(err);
  });