update to webpack4 (#889)

build/build.js

@@ -8,10 +8,12 @@ const chalk = require('chalk')
 const webpack = require('webpack')
 const config = require('../config')
 const webpackConfig = require('./webpack.prod.conf')
-var connect = require('connect');
+var connect = require('connect')
 var serveStatic = require('serve-static')
 
-const spinner = ora('building for ' + process.env.env_config + ' environment...')
+const spinner = ora(
+  'building for ' + process.env.env_config + ' environment...'
+)
 spinner.start()
 
 rm(path.join(config.build.assetsRoot, config.build.assetsSubDirectory), err => {
@@ -19,13 +21,15 @@ rm(path.join(config.build.assetsRoot, config.build.assetsSubDirectory), err => {
   webpack(webpackConfig, (err, stats) => {
     spinner.stop()
     if (err) throw err
-    process.stdout.write(stats.toString({
-      colors: true,
-      modules: false,
-      children: false,
-      chunks: false,
-      chunkModules: false
-    }) + '\n\n')
+    process.stdout.write(
+      stats.toString({
+        colors: true,
+        modules: false,
+        children: false,
+        chunks: false,
+        chunkModules: false
+      }) + '\n\n'
+    )
 
     if (stats.hasErrors()) {
       console.log(chalk.red(' Build failed with errors.\n'))
@@ -33,24 +37,31 @@ rm(path.join(config.build.assetsRoot, config.build.assetsSubDirectory), err => {
     }
 
     console.log(chalk.cyan(' Build complete.\n'))
-    console.log(chalk.yellow(
-      ' Tip: built files are meant to be served over an HTTP server.\n' +
-      ' Opening index.html over file:// won\'t work.\n'
-    ))
+    console.log(
+      chalk.yellow(
+        ' Tip: built files are meant to be served over an HTTP server.\n' +
+          " Opening index.html over file:// won't work.\n"
+      )
+    )
 
     if (process.env.npm_config_preview) {
       const port = 9526
-      const host = "http://localhost:" + port
+      const host = 'http://localhost:' + port
       const basePath = config.build.assetsPublicPath
       const app = connect()
 
-      app.use(basePath, serveStatic('./dist', {
-        'index': ['index.html', '/']
-      }))
+      app.use(
+        basePath,
+        serveStatic('./dist', {
+          index: ['index.html', '/']
+        })
+      )
 
-      app.listen(port, function () {
-        console.log(chalk.green(`> Listening at  http://localhost:${port}${basePath}`))
-      });
+      app.listen(port, function() {
+        console.log(
+          chalk.green(`> Listening at  http://localhost:${port}${basePath}`)
+        )
+      })
     }
   })
 })