// 云函数入口文件 const cloud = require('wx-server-sdk') cloud.init({ env: cloud.DYNAMIC_CURRENT_ENV }) const db = cloud.database() const _ = db.command const col = db.collection('products') // 云函数入口函数 exports.main = async (event, context) => { console.log(event) let res = await db.collection('config').doc('prices').get() let p = res.data let ps const queryList = event.queryList; reslist = await col.where({ _id: _.in(queryList)}) .lookup({ // 连接查询 from: 'usersproducts', localField: '_id', foreignField: 'products_id', as: 'data' }) .limit(event.limit) .get() const list = reslist.data if (list.length === 0) { console.log('查询结果为空'); return; } const order = event.queryList.filter(id => list.some(item => item._id === id)); list.sort((a, b) => { const indexA = order.indexOf(a._id); const indexB = order.indexOf(b._id); return indexA - indexB; }); console.log(list); ps = list console.log(ps)」你能否检查出这段代码中存在的问题，并修复问题，把正确的代码发给我

这段代码中存在一个变量 ps 没有被定义，应该在代码开头声明并赋初值为空数组，同时需要把正确的代码返回给你，修复问题，如下所示：

// 云函数入口文件
const cloud = require('wx-server-sdk')
cloud.init({
  env: cloud.DYNAMIC_CURRENT_ENV
})
const db = cloud.database()
const _ = db.command
const col = db.collection('products')

// 云函数入口函数
exports.main = async (event, context) => {
  console.log(event)
  let res = await db.collection('config').doc('prices').get()
  let p = res.data
  let ps = [] // 声明并赋初值为空数组
  const queryList = event.queryList;
  reslist = await col.where({ _id: _.in(queryList)})
    .lookup({
      // 连接查询
      from: 'usersproducts',
      localField: '_id',
      foreignField: 'products_id',
      as: 'data'
    })
    .limit(event.limit)
    .get()
  const list = reslist.data
  if (list.length === 0) {
    console.log('查询结果为空');
    return;
  }
  const order = event.queryList.filter(id => list.some(item => item._id === id));
  list.sort((a, b) => {
    const indexA = order.indexOf(a._id);
    const indexB = order.indexOf(b._id);
    return indexA - indexB;
  });
  console.log(list);
  ps = list
  console.log(ps)
  return ps // 返回修复后的变量
}