Uncaught TypeError: mix is not a constructor

引入如下js文件

//home.wpy
import mix from '@/mixins/tabs/xxx.js'
export default class extends wepy.page {
     mixins=[mix]
}

//xxx.js
import wepy from 'wepy'
export default class extends wepy.mixin{
  data = {
      ...
    }
    onLoad() {
            this.getData()
        }
    async getData() {
            const { data: res } = await wepy.request({
                url: 'xxxx',
                method: 'GET',
                data: {}
            })
          ...
        }
}

保存xxx.js文件，或wepy文件时间歇报错Uncaught TypeError: mix is not a constructor

代码没问题 偶发编译问题