Error in render: "TypeError: parentVal.concat is not a function"

[Ge-yuan-jun]

demo link

Repeatable demo link: https://github.com/Ge-yuan-jun/vue-routing-demo

expectation

change code in router/index.js & main.js, the plugin should still work

When I use this plugin by default config, It works.

But when I change the router config, modify the index.js in router folder like this:

router/index.js

import routes from 'vue-auto-routing'
import { createRouterLayout } from 'vue-router-layout'

const RouterLayout = createRouterLayout(layout => {
  return import('@/layouts/' + layout + '.vue')
})

const generateRoutes = [
  {
    path: '/',
    component: RouterLayout,
    children: routes
  }
]

export default generateRoutes

and add cde like this in main.js

import Vue from 'vue'
import Router from 'vue-router'
import App from './App.vue'
import routes from './router'

Vue.use(Router)

Vue.config.productionTip = false

const router = new Router({
  routes
})

new Vue({
  router,
  render: h => h(App)
}).$mount('#app')

result

when I load the page, it shows the error 'Error in render: "TypeError: parentVal.concat is not a function"'

what I want

I want to know if the plugin can work if I change export varaible like the demo