UglifyJS throws Unexpected token: keyword (const) in build about vue-timers HOT 6 CLOSED

module: {
    rules: [
      {
        test: /\.js$/,
        loader: 'babel-loader',
        include: [resolve('src'), resolve('node_modules/vue-timers')],
      }
    ]
  }

var path = require('path')
var utils = require('./utils')
var config = require('../config')
var vueLoaderConfig = require('./vue-loader.conf')
var fs = require('fs')

const { VueLoaderPlugin } = require('vue-loader')

function resolve (dir) {
  return path.join(__dirname, '..', dir)
}

module.exports = {
  entry: {
    app: ['@babel/polyfill','./src/main.js']
  },
  output: {
    path: config.build.assetsRoot,
    filename: '[name].js',
    publicPath: process.env.NODE_ENV === 'production'
      ? config.build.assetsPublicPath
      : config.dev.assetsPublicPath
  },
  resolve: {
    extensions: ['.js', '.vue', '.json'],
    alias: {
      'vue$': 'vue/dist/vue.esm.js',
      '@': resolve('src')
    }
  },
  module: {
    rules: [
      {
        test: /\.(js|vue)$/,
        loader: 'eslint-loader',
        enforce: 'pre',
        include: [resolve('src'), resolve('test'), resolve('node_modules/vue-timers')],
        options: {
          formatter: require('eslint-friendly-formatter')
        }
      },
      {
        test: /\.vue$/,
        loader: 'vue-loader',
        options: vueLoaderConfig
      },
      {
        test: /\.js$/,
        loader: 'babel-loader',
        include: [resolve('src'), resolve('test'), resolve('node_modules/vue-timers')]
      },
      {
        test: /\.(png|jpe?g|gif|svg)(\?.*)?$/,
        loader: 'url-loader',
        options: {
          limit: 10000,
          name: utils.assetsPath('img/[name].[hash:7].[ext]')
        }
      },
      {
        test: /\.(mp4|webm|ogg|mp3|wav|flac|aac)(\?.*)?$/,
        loader: 'url-loader',
        options: {
          limit: 10000,
          name: utils.assetsPath('media/[name].[hash:7].[ext]')
        }
      },
      {
        test: /\.(woff2?|eot|ttf|otf)(\?.*)?$/,
        loader: 'url-loader',
        options: {
          limit: 10000,
          name: utils.assetsPath('fonts/[name].[hash:7].[ext]'),
          // workaround for vuejs-templates webpack issue 1266
          publicPath: process.env.NODE_ENV === 'production' ? '../' : '/'
        }
      }
    ]
  },
  plugins: [
    new VueLoaderPlugin()
  ]
}

{
  "presets": [
    [
      "@babel/env",
      {
        "modules": false,
        "targets": {
          "browsers": [
            "> 1%",
            "last 2 versions",
            "not ie <= 8"
          ]
        }
      }
    ]
  ],
  "plugins": [
    "@babel/plugin-transform-runtime",
    [
      "@babel/plugin-proposal-decorators",
      {
        "legacy": true
      }
    ],
    "@babel/plugin-proposal-function-sent",
    "@babel/plugin-proposal-export-namespace-from",
    "@babel/plugin-proposal-numeric-separator",
    "@babel/plugin-proposal-throw-expressions",
    "@babel/plugin-syntax-dynamic-import",
    "@babel/plugin-syntax-import-meta",
    [
      "@babel/plugin-proposal-class-properties",
      {
        "loose": false
      }
    ],
    "@babel/plugin-proposal-json-strings"
  ],
  "env": {
    "test": {
      "presets": [
        "@babel/env"
      ],
      "plugins": [
        "istanbul",
        [
          "@babel/plugin-proposal-decorators",
          {
            "legacy": true
          }
        ],
        "@babel/plugin-proposal-function-sent",
        "@babel/plugin-proposal-export-namespace-from",
        "@babel/plugin-proposal-numeric-separator",
        "@babel/plugin-proposal-throw-expressions",
        "@babel/plugin-syntax-dynamic-import",
        "@babel/plugin-syntax-import-meta",
        [
          "@babel/plugin-proposal-class-properties",
          {
            "loose": false
          }
        ],
        "@babel/plugin-proposal-json-strings"
      ]
    }
  }
}