update to webpack4 (#889)

build/utils.js

@@ -1,18 +1,19 @@
 'use strict'
 const path = require('path')
 const config = require('../config')
-const ExtractTextPlugin = require('extract-text-webpack-plugin')
+const MiniCssExtractPlugin = require('mini-css-extract-plugin')
 const packageConfig = require('../package.json')
 
-exports.assetsPath = function (_path) {
-  const assetsSubDirectory = process.env.NODE_ENV === 'production'
-    ? config.build.assetsSubDirectory
-    : config.dev.assetsSubDirectory
+exports.assetsPath = function(_path) {
+  const assetsSubDirectory =
+    process.env.NODE_ENV === 'production'
+      ? config.build.assetsSubDirectory
+      : config.dev.assetsSubDirectory
 
   return path.posix.join(assetsSubDirectory, _path)
 }
 
-exports.cssLoaders = function (options) {
+exports.cssLoaders = function(options) {
   options = options || {}
 
   const cssLoader = {
@@ -30,8 +31,22 @@ exports.cssLoaders = function (options) {
   }
 
   // generate loader string to be used with extract text plugin
-  function generateLoaders (loader, loaderOptions) {
-    const loaders = options.usePostCSS ? [cssLoader, postcssLoader] : [cssLoader]
+  function generateLoaders(loader, loaderOptions) {
+    const loaders = []
+
+    // Extract CSS when that option is specified
+    // (which is the case during production build)
+    if (options.extract) {
+      loaders.push(MiniCssExtractPlugin.loader)
+    } else {
+      loaders.push('vue-style-loader')
+    }
+
+    loaders.push(cssLoader)
+
+    if (options.usePostCSS) {
+      loaders.push(postcssLoader)
+    }
 
     if (loader) {
       loaders.push({
@@ -42,24 +57,16 @@ exports.cssLoaders = function (options) {
       })
     }
 
-    // Extract CSS when that option is specified
-    // (which is the case during production build)
-    if (options.extract) {
-      return ExtractTextPlugin.extract({
-        use: loaders,
-        fallback: 'vue-style-loader'
-      })
-    } else {
-      return ['vue-style-loader'].concat(loaders)
-    }
+    return loaders
   }
-
   // https://vue-loader.vuejs.org/en/configurations/extract-css.html
   return {
     css: generateLoaders(),
     postcss: generateLoaders(),
     less: generateLoaders('less'),
-    sass: generateLoaders('sass', { indentedSyntax: true }),
+    sass: generateLoaders('sass', {
+      indentedSyntax: true
+    }),
     scss: generateLoaders('sass'),
     stylus: generateLoaders('stylus'),
     styl: generateLoaders('stylus')
@@ -67,7 +74,7 @@ exports.cssLoaders = function (options) {
 }
 
 // Generate loaders for standalone style files (outside of .vue)
-exports.styleLoaders = function (options) {
+exports.styleLoaders = function(options) {
   const output = []
   const loaders = exports.cssLoaders(options)