错误信息

Cannot find module '@/views/login/index'
Failed to resolve async component default
vue-router.esm.js:1897 Error: Cannot find module '@/views/login/index'
at webpackEmptyContext (index.js:39)
at permission.js:90

解决方法
进入router中的index.js

component: () => import('@/views/login/index'),

改为

component: (resolve) => require(["@/views/login/index"], resolve),

如果是动态路由则

export const loadView = (view) => { // 路由懒加载
  return () => import(`@/views/${view}`)
}

改为

export const loadView = (view) => { // 路由懒加载
  return (resolve) => require([`@/views/${view}`], resolve)
}

错误原因是老外修改了webpack打包逻辑，webpack4中动态import不支持变量方式，
该修改对于生产环境无影响，只在开发环境有问题

如果解决了你的问题，请回来点赞哦。