Error in beforeCreate hook: "SyntaxError: missing ) after argument list"

[LensHunnel]

1. vue init webpack test
2. npm install nprogress
3. edit main.js

import Vue from 'vue'
import NProgress from 'vue-nprogress'
import App from './App.vue'

Vue.use(NProgress)

const nprogress = new NProgress({ parent: '.nprogress-container' })

const app = new Vue({
  nprogress,
  ...App
})
app.$mount('#app')

4. edit App.vue

<template>
  <nprogress-container></nprogress-container>
</template>

<script>
import NprogressContainer from 'vue-nprogress/src/NprogressContainer'

export default {
  components: {
    NprogressContainer
  }
}
</script>

5. npm run dev
   works fine

6. console shows:
   vue.esm.js?efeb:578 [Vue warn]: Error in beforeCreate hook: "SyntaxError: missing ) after argument list"
   found in
   ---> at node_modules/vue-nprogress/src/NprogressContainer.vue

[SamWoolerton]

Just encountered this too. Interestingly, only happens when dev server has --hot flags for HMR, removing that prevents the error for me

[dizid]

Same here: with --hot flag in webpack.dev.conf.js it produces that same error.