From 6234ae84c0b8adb23b0874ef20ef4f73f3944b2d Mon Sep 17 00:00:00 2001
From: Pooya Parsa <pooya@pi0.ir>
Date: Fri, 16 Mar 2018 22:41:24 +0330
Subject: [PATCH] refactor(core): use strict mjs

---
 lib/builder/{builder.js => builder.mjs}       | 60 +++++++++----------
 lib/builder/{generator.js => generator.mjs}   | 52 ++++++++--------
 lib/builder/{index.js => index.mjs}           |  0
 .../{base.config.js => base.config.mjs}       | 20 +++----
 .../{client.config.js => client.config.mjs}   | 14 ++---
 .../plugins/{progress.js => progress.mjs}     |  0
 .../plugins/vue/{client.js => client.mjs}     |  0
 .../plugins/vue/{server.js => server.mjs}     |  0
 .../webpack/plugins/vue/{util.js => util.mjs} |  0
 .../plugins/{warnfix.js => warnfix.mjs}       |  0
 .../webpack/{postcss.js => postcss.mjs}       | 20 +++----
 .../{server.config.js => server.config.mjs}   | 14 ++---
 lib/builder/webpack/style-loader.js           |  6 +-
 .../webpack/{vue-loader.js => vue-loader.mjs} |  0
 lib/common/{modes.js => modes.mjs}            |  0
 lib/common/nuxt.config.js                     |  6 +-
 lib/common/{options.js => options.mjs}        | 24 ++++----
 lib/common/{utils.js => utils.mjs}            | 31 +++++-----
 lib/core/{index.js => index.mjs}              |  0
 lib/core/{meta.js => meta.mjs}                |  0
 lib/core/middleware/{error.js => error.mjs}   | 14 ++---
 lib/core/middleware/{nuxt.js => nuxt.mjs}     |  0
 lib/core/{module.js => module.mjs}            |  0
 lib/core/{nuxt.js => nuxt.mjs}                | 42 ++++++-------
 lib/core/{renderer.js => renderer.mjs}        | 24 ++++----
 25 files changed, 164 insertions(+), 163 deletions(-)
 rename lib/builder/{builder.js => builder.mjs} (90%)
 rename lib/builder/{generator.js => generator.mjs} (82%)
 rename lib/builder/{index.js => index.mjs} (100%)
 rename lib/builder/webpack/{base.config.js => base.config.mjs} (91%)
 rename lib/builder/webpack/{client.config.js => client.config.mjs} (91%)
 rename lib/builder/webpack/plugins/{progress.js => progress.mjs} (100%)
 rename lib/builder/webpack/plugins/vue/{client.js => client.mjs} (100%)
 rename lib/builder/webpack/plugins/vue/{server.js => server.mjs} (100%)
 rename lib/builder/webpack/plugins/vue/{util.js => util.mjs} (100%)
 rename lib/builder/webpack/plugins/{warnfix.js => warnfix.mjs} (100%)
 rename lib/builder/webpack/{postcss.js => postcss.mjs} (81%)
 rename lib/builder/webpack/{server.config.js => server.config.mjs} (90%)
 rename lib/builder/webpack/{vue-loader.js => vue-loader.mjs} (100%)
 rename lib/common/{modes.js => modes.mjs} (100%)
 rename lib/common/{options.js => options.mjs} (85%)
 rename lib/common/{utils.js => utils.mjs} (93%)
 rename lib/core/{index.js => index.mjs} (100%)
 rename lib/core/{meta.js => meta.mjs} (100%)
 rename lib/core/middleware/{error.js => error.mjs} (88%)
 rename lib/core/middleware/{nuxt.js => nuxt.mjs} (100%)
 rename lib/core/{module.js => module.mjs} (100%)
 rename lib/core/{nuxt.js => nuxt.mjs} (82%)
 rename lib/core/{renderer.js => renderer.mjs} (94%)

diff --git a/lib/builder/builder.js b/lib/builder/builder.mjs
similarity index 90%
rename from lib/builder/builder.js
rename to lib/builder/builder.mjs
index f29a3d5a38..b9b4a8b21b 100644
--- a/lib/builder/builder.js
+++ b/lib/builder/builder.mjs
@@ -1,12 +1,12 @@
-import { promisify } from 'util'
+import util from 'util'
 import _ from 'lodash'
 import chokidar from 'chokidar'
-import { remove, readFile, writeFile, mkdirp, existsSync } from 'fs-extra'
+import fsExtra from 'fs-extra'
 import fs from 'fs'
 import hash from 'hash-sum'
 import webpack from 'webpack'
 import serialize from 'serialize-javascript'
-import { join, resolve, basename, extname, dirname } from 'path'
+import path from 'path'
 import MFS from 'memory-fs'
 import webpackDevMiddleware from 'webpack-dev-middleware'
 import webpackHotMiddleware from 'webpack-hot-middleware'
@@ -14,14 +14,14 @@ import Debug from 'debug'
 import Glob from 'glob'
 import { r, wp, wChunk, createRoutes, parallel, relativeTo, waitFor, createSpinner } from '../common/utils'
 import Options from '../common/options'
-import clientWebpackConfig from './webpack/client.config.js'
-import serverWebpackConfig from './webpack/server.config.js'
+import clientWebpackConfig from './webpack/client.config'
+import serverWebpackConfig from './webpack/server.config'
 import upath from 'upath'
 
 const debug = Debug('nuxt:build')
 debug.color = 2 // Force green color
 
-const glob = promisify(Glob)
+const glob = util.promisify(Glob)
 
 export default class Builder {
   constructor(nuxt) {
@@ -61,7 +61,7 @@ export default class Builder {
     return _.uniqBy(
       this.options.plugins.map((p, i) => {
         if (typeof p === 'string') p = { src: p }
-        const pluginBaseName = basename(p.src, extname(p.src)).replace(
+        const pluginBaseName = path.basename(p.src, path.extname(p.src)).replace(
           /[^a-zA-Z?\d\s:]/g,
           ''
         )
@@ -104,9 +104,9 @@ export default class Builder {
     // Check if pages dir exists and warn if not
     this._nuxtPages = typeof this.options.build.createRoutes !== 'function'
     if (this._nuxtPages) {
-      if (!existsSync(join(this.options.srcDir, this.options.dir.pages))) {
+      if (!fsExtra.existsSync(path.join(this.options.srcDir, this.options.dir.pages))) {
         let dir = this.options.srcDir
-        if (existsSync(join(this.options.srcDir, '..', this.options.dir.pages))) {
+        if (fsExtra.existsSync(path.join(this.options.srcDir, '..', this.options.dir.pages))) {
           throw new Error(
             `No \`${this.options.dir.pages}\` directory found in ${dir}. Did you mean to run \`nuxt\` in the parent (\`../\`) directory?`
           )
@@ -123,10 +123,10 @@ export default class Builder {
     debug(`App root: ${this.options.srcDir}`)
 
     // Create .nuxt/, .nuxt/components and .nuxt/dist folders
-    await remove(r(this.options.buildDir))
-    await mkdirp(r(this.options.buildDir, 'components'))
+    await fsExtra.remove(r(this.options.buildDir))
+    await fsExtra.mkdirp(r(this.options.buildDir, 'components'))
     if (!this.options.dev) {
-      await mkdirp(r(this.options.buildDir, 'dist'))
+      await fsExtra.mkdirp(r(this.options.buildDir, 'dist'))
     }
 
     // Generate routes and interpret the template files
@@ -215,7 +215,7 @@ export default class Builder {
       router: this.options.router,
       env: this.options.env,
       head: this.options.head,
-      middleware: existsSync(join(this.options.srcDir, this.options.dir.middleware)),
+      middleware: fsExtra.existsSync(path.join(this.options.srcDir, this.options.dir.middleware)),
       store: this.options.store,
       css: this.options.css,
       plugins: this.plugins,
@@ -237,7 +237,7 @@ export default class Builder {
     }
 
     // -- Layouts --
-    if (existsSync(resolve(this.options.srcDir, this.options.dir.layouts))) {
+    if (fsExtra.existsSync(path.resolve(this.options.srcDir, this.options.dir.layouts))) {
       const layoutsFiles = await glob(`${this.options.dir.layouts}/**/*.{vue,js}`, {
         cwd: this.options.srcDir,
         ignore: this.options.ignore
@@ -269,7 +269,7 @@ export default class Builder {
     }
     // If no default layout, create its folder and add the default folder
     if (!templateVars.layouts.default) {
-      await mkdirp(r(this.options.buildDir, 'layouts'))
+      await fsExtra.mkdirp(r(this.options.buildDir, 'layouts'))
       templatesFiles.push('layouts/default.vue')
       templateVars.layouts.default = './layouts/default.vue'
     }
@@ -330,7 +330,7 @@ export default class Builder {
 
     // Resolve template files
     const customTemplateFiles = this.options.build.templates.map(
-      t => t.dst || basename(t.src || t)
+      t => t.dst || path.basename(t.src || t)
     )
 
     templatesFiles = templatesFiles
@@ -341,7 +341,7 @@ export default class Builder {
         }
         // Allow override templates using a file with same name in ${srcDir}/app
         const customPath = r(this.options.srcDir, 'app', file)
-        const customFileExists = existsSync(customPath)
+        const customFileExists = fsExtra.existsSync(customPath)
 
         return {
           src: customFileExists ? customPath : r(this.options.nuxtAppDir, file),
@@ -358,7 +358,7 @@ export default class Builder {
         return Object.assign(
           {
             src: r(this.options.srcDir, t.src || t),
-            dst: t.dst || basename(t.src || t),
+            dst: t.dst || path.basename(t.src || t),
             custom: true
           },
           t
@@ -368,7 +368,7 @@ export default class Builder {
 
     // -- Loading indicator --
     if (this.options.loadingIndicator.name) {
-      const indicatorPath1 = resolve(
+      const indicatorPath1 = path.resolve(
         this.options.nuxtAppDir,
         'views/loading',
         this.options.loadingIndicator.name + '.html'
@@ -376,9 +376,9 @@ export default class Builder {
       const indicatorPath2 = this.nuxt.resolveAlias(
         this.options.loadingIndicator.name
       )
-      const indicatorPath = existsSync(indicatorPath1)
+      const indicatorPath = fsExtra.existsSync(indicatorPath1)
         ? indicatorPath1
-        : existsSync(indicatorPath2) ? indicatorPath2 : null
+        : fsExtra.existsSync(indicatorPath2) ? indicatorPath2 : null
       if (indicatorPath) {
         templatesFiles.push({
           src: indicatorPath,
@@ -408,7 +408,7 @@ export default class Builder {
         // Add template to watchers
         this.options.build.watch.push(src)
         // Render template to dst
-        const fileContent = await readFile(src, 'utf8')
+        const fileContent = await fsExtra.readFile(src, 'utf8')
         let content
         try {
           const template = _.template(fileContent, {
@@ -435,11 +435,11 @@ export default class Builder {
           /* istanbul ignore next */
           throw new Error(`Could not compile template ${src}: ${err.message}`)
         }
-        const path = r(this.options.buildDir, dst)
+        const _path = r(this.options.buildDir, dst)
         // Ensure parent dir exits
-        await mkdirp(dirname(path))
+        await fsExtra.mkdirp(path.dirname(_path))
         // Write file
-        await writeFile(path, content, 'utf8')
+        await fsExtra.writeFile(_path, content, 'utf8')
       })
     )
 
@@ -544,7 +544,7 @@ export default class Builder {
     debug('Adding webpack middleware...')
 
     // Create webpack dev middleware
-    this.webpackDevMiddleware = promisify(
+    this.webpackDevMiddleware = util.promisify(
       webpackDevMiddleware(
         compiler,
         Object.assign(
@@ -559,9 +559,9 @@ export default class Builder {
       )
     )
 
-    this.webpackDevMiddleware.close = promisify(this.webpackDevMiddleware.close)
+    this.webpackDevMiddleware.close = util.promisify(this.webpackDevMiddleware.close)
 
-    this.webpackHotMiddleware = promisify(
+    this.webpackHotMiddleware = util.promisify(
       webpackHotMiddleware(
         compiler,
         Object.assign(
@@ -644,9 +644,9 @@ export default class Builder {
 
   // TODO: remove ignore when generateConfig enabled again
   async generateConfig() /* istanbul ignore next */ {
-    const config = resolve(this.options.buildDir, 'build.config.js')
+    const config = path.resolve(this.options.buildDir, 'build.config.js')
     const options = _.omit(this.options, Options.unsafeKeys)
-    await writeFile(
+    await fsExtra.writeFile(
       config,
       `export default ${JSON.stringify(options, null, '  ')}`,
       'utf8'
diff --git a/lib/builder/generator.js b/lib/builder/generator.mjs
similarity index 82%
rename from lib/builder/generator.js
rename to lib/builder/generator.mjs
index bf1995b28b..0da99d3878 100644
--- a/lib/builder/generator.js
+++ b/lib/builder/generator.mjs
@@ -1,8 +1,8 @@
 import _ from 'lodash'
-import { resolve, join, dirname, sep } from 'path'
-import { minify } from 'html-minifier'
+import path from 'path'
+import htmlMinifier from 'html-minifier'
 import Chalk from 'chalk'
-import { copy, remove, writeFile, mkdirp, removeSync, existsSync } from 'fs-extra'
+import fsExtra from 'fs-extra'
 import { isUrl, promisifyRoute, waitFor, flatRoutes, printWarn, createSpinner } from '../common/utils'
 
 export default class Generator {
@@ -12,10 +12,10 @@ export default class Generator {
     this.builder = builder
 
     // Set variables
-    this.staticRoutes = resolve(this.options.srcDir, this.options.dir.static)
-    this.srcBuiltPath = resolve(this.options.buildDir, 'dist')
-    this.distPath = resolve(this.options.rootDir, this.options.generate.dir)
-    this.distNuxtPath = join(
+    this.staticRoutes = path.resolve(this.options.srcDir, this.options.dir.static)
+    this.srcBuiltPath = path.resolve(this.options.buildDir, 'dist')
+    this.distPath = path.resolve(this.options.rootDir, this.options.generate.dir)
+    this.distNuxtPath = path.join(
       this.distPath,
       isUrl(this.options.build.publicPath) ? '' : this.options.build.publicPath
     )
@@ -127,7 +127,7 @@ export default class Generator {
         if (isHandled) {
           line += Chalk.grey(JSON.stringify(error, undefined, 2) + '\n')
         } else {
-          line += Chalk.grey(error.toString())
+          line += Chalk.grey(error.stack)
         }
 
         return line
@@ -141,36 +141,36 @@ export default class Generator {
     // Disable SPA fallback if value isn't true or a string
     if (fallback !== true && typeof fallback !== 'string') return
 
-    const fallbackPath = join(this.distPath, fallback)
+    const fallbackPath = path.join(this.distPath, fallback)
 
     // Prevent conflicts
-    if (existsSync(fallbackPath)) {
+    if (fsExtra.existsSync(fallbackPath)) {
       printWarn(`SPA fallback was configured, but the configured path (${fallbackPath}) already exists.`)
       return
     }
 
     // Render and write the SPA template to the fallback path
     const { html } = await this.nuxt.renderRoute('/', { spa: true })
-    await writeFile(fallbackPath, html, 'utf8')
+    await fsExtra.writeFile(fallbackPath, html, 'utf8')
   }
 
   async initDist() {
     // Clean destination folder
-    await remove(this.distPath)
+    await fsExtra.remove(this.distPath)
 
     await this.nuxt.callHook('generate:distRemoved', this)
 
     // Copy static and built files
     /* istanbul ignore if */
-    if (existsSync(this.staticRoutes)) {
-      await copy(this.staticRoutes, this.distPath)
+    if (fsExtra.existsSync(this.staticRoutes)) {
+      await fsExtra.copy(this.staticRoutes, this.distPath)
     }
-    await copy(this.srcBuiltPath, this.distNuxtPath)
+    await fsExtra.copy(this.srcBuiltPath, this.distNuxtPath)
 
     // Add .nojekyll file to let Github Pages add the _nuxt/ folder
     // https://help.github.com/articles/files-that-start-with-an-underscore-are-missing/
-    const nojekyllPath = resolve(this.distPath, '.nojekyll')
-    writeFile(nojekyllPath, '')
+    const nojekyllPath = path.resolve(this.distPath, '.nojekyll')
+    fsExtra.writeFile(nojekyllPath, '')
 
     // Cleanup SSR related files
     const extraFiles = [
@@ -178,11 +178,11 @@ export default class Generator {
       'index.ssr.html',
       'server-bundle.json',
       'vue-ssr-client-manifest.json'
-    ].map(file => resolve(this.distNuxtPath, file))
+    ].map(file => path.resolve(this.distNuxtPath, file))
 
     extraFiles.forEach(file => {
-      if (existsSync(file)) {
-        removeSync(file)
+      if (fsExtra.existsSync(file)) {
+        fsExtra.removeSync(file)
       }
     })
 
@@ -238,7 +238,7 @@ export default class Generator {
 
     if (this.options.generate.minify) {
       try {
-        html = minify(html, this.options.generate.minify)
+        html = htmlMinifier.minify(html, this.options.generate.minify)
       } catch (err) /* istanbul ignore next */ {
         const minifyErr = new Error(
           `HTML minification failed. Make sure the route generates valid HTML. Failed HTML:\n ${html}`
@@ -250,22 +250,22 @@ export default class Generator {
     let path
 
     if (this.options.generate.subFolders) {
-      path = join(route, sep, 'index.html') // /about -> /about/index.html
+      path = path.join(route, path.sep, 'index.html') // /about -> /about/index.html
       path = path === '/404/index.html' ? '/404.html' : path // /404 -> /404.html
     } else {
       path =
-        route.length > 1 ? join(sep, route + '.html') : join(sep, 'index.html')
+        route.length > 1 ? path.join(path.sep, route + '.html') : path.join(path.sep, 'index.html')
     }
 
     // Call hook to let user update the path & html
     const page = { route, path, html }
     await this.nuxt.callHook('generate:page', page)
 
-    page.path = join(this.distPath, page.path)
+    page.path = path.join(this.distPath, page.path)
 
     // Make sure the sub folders are created
-    await mkdirp(dirname(page.path))
-    await writeFile(page.path, page.html, 'utf8')
+    await fsExtra.mkdirp(path.dirname(page.path))
+    await fsExtra.writeFile(page.path, page.html, 'utf8')
 
     await this.nuxt.callHook('generate:routeCreated', {
       route,
diff --git a/lib/builder/index.js b/lib/builder/index.mjs
similarity index 100%
rename from lib/builder/index.js
rename to lib/builder/index.mjs
diff --git a/lib/builder/webpack/base.config.js b/lib/builder/webpack/base.config.mjs
similarity index 91%
rename from lib/builder/webpack/base.config.js
rename to lib/builder/webpack/base.config.mjs
index b60e72eaaa..9cfc79c933 100644
--- a/lib/builder/webpack/base.config.js
+++ b/lib/builder/webpack/base.config.mjs
@@ -4,8 +4,8 @@ import WarnFixPlugin from './plugins/warnfix'
 import ProgressPlugin from './plugins/progress'
 
 import webpack from 'webpack'
-import { cloneDeep } from 'lodash'
-import { join, resolve } from 'path'
+import _ from 'lodash'
+import path from 'path'
 
 import { isUrl, urlJoin } from '../../common/utils'
 
@@ -28,11 +28,11 @@ export default function webpackBaseConfig({ name, isServer }) {
 
   // Used by vue-loader so we can use in templates
   // with <img src="~/assets/nuxt.png"/>
-  configAlias[this.options.dir.assets] = join(
+  configAlias[this.options.dir.assets] = path.join(
     this.options.srcDir,
     this.options.dir.assets
   )
-  configAlias[this.options.dir.static] = join(
+  configAlias[this.options.dir.static] = path.join(
     this.options.srcDir,
     this.options.dir.static
   )
@@ -45,7 +45,7 @@ export default function webpackBaseConfig({ name, isServer }) {
     },
     optimization: {},
     output: {
-      path: resolve(this.options.buildDir, 'dist'),
+      path: path.resolve(this.options.buildDir, 'dist'),
       filename: this.getFileName('app'),
       chunkFilename: this.getFileName('chunk'),
       publicPath: isUrl(this.options.build.publicPath)
@@ -61,10 +61,10 @@ export default function webpackBaseConfig({ name, isServer }) {
       extensions: ['.js', '.json', '.vue', '.jsx'],
       alias: Object.assign(
         {
-          '~': join(this.options.srcDir),
-          '~~': join(this.options.rootDir),
-          '@': join(this.options.srcDir),
-          '@@': join(this.options.rootDir)
+          '~': path.join(this.options.srcDir),
+          '~~': path.join(this.options.rootDir),
+          '@': path.join(this.options.srcDir),
+          '@@': path.join(this.options.rootDir)
         },
         configAlias
       ),
@@ -159,5 +159,5 @@ export default function webpackBaseConfig({ name, isServer }) {
   }
 
   // Clone deep avoid leaking config between Client and Server
-  return cloneDeep(config)
+  return _.cloneDeep(config)
 }
diff --git a/lib/builder/webpack/client.config.js b/lib/builder/webpack/client.config.mjs
similarity index 91%
rename from lib/builder/webpack/client.config.js
rename to lib/builder/webpack/client.config.mjs
index 0978e065b2..f5ec4a0248 100644
--- a/lib/builder/webpack/client.config.js
+++ b/lib/builder/webpack/client.config.mjs
@@ -1,14 +1,14 @@
-import { each } from 'lodash'
+import _ from 'lodash'
 import webpack from 'webpack'
 // import VueSSRClientPlugin from 'vue-server-renderer/client-plugin'
 import VueSSRClientPlugin from './plugins/vue/client'
 import HTMLPlugin from 'html-webpack-plugin'
 import FriendlyErrorsWebpackPlugin from '@nuxtjs/friendly-errors-webpack-plugin'
 import StylishPlugin from 'webpack-stylish'
-import { BundleAnalyzerPlugin } from 'webpack-bundle-analyzer'
-import { resolve } from 'path'
+import BundleAnalyzer from 'webpack-bundle-analyzer'
+import path from 'path'
 import Debug from 'debug'
-import base from './base.config.js'
+import base from './base.config'
 
 const debug = Debug('nuxt:build')
 debug.color = 2 // Force green color
@@ -17,11 +17,11 @@ export default function webpackClientConfig() {
   let config = base.call(this, { name: 'client', isServer: false })
 
   // Entry points
-  config.entry.app = resolve(this.options.buildDir, 'client.js')
+  config.entry.app = path.resolve(this.options.buildDir, 'client.js')
 
   // Env object defined in nuxt.config.js
   let env = {}
-  each(this.options.env, (value, key) => {
+  _.each(this.options.env, (value, key) => {
     env['process.env.' + key] =
       ['boolean', 'number'].indexOf(typeof value) !== -1
         ? value
@@ -128,7 +128,7 @@ export default function webpackClientConfig() {
     // Webpack Bundle Analyzer
     if (this.options.build.analyze) {
       config.plugins.push(
-        new BundleAnalyzerPlugin(Object.assign({}, this.options.build.analyze))
+        new BundleAnalyzer.BundleAnalyzerPlugin(Object.assign({}, this.options.build.analyze))
       )
     }
   }
diff --git a/lib/builder/webpack/plugins/progress.js b/lib/builder/webpack/plugins/progress.mjs
similarity index 100%
rename from lib/builder/webpack/plugins/progress.js
rename to lib/builder/webpack/plugins/progress.mjs
diff --git a/lib/builder/webpack/plugins/vue/client.js b/lib/builder/webpack/plugins/vue/client.mjs
similarity index 100%
rename from lib/builder/webpack/plugins/vue/client.js
rename to lib/builder/webpack/plugins/vue/client.mjs
diff --git a/lib/builder/webpack/plugins/vue/server.js b/lib/builder/webpack/plugins/vue/server.mjs
similarity index 100%
rename from lib/builder/webpack/plugins/vue/server.js
rename to lib/builder/webpack/plugins/vue/server.mjs
diff --git a/lib/builder/webpack/plugins/vue/util.js b/lib/builder/webpack/plugins/vue/util.mjs
similarity index 100%
rename from lib/builder/webpack/plugins/vue/util.js
rename to lib/builder/webpack/plugins/vue/util.mjs
diff --git a/lib/builder/webpack/plugins/warnfix.js b/lib/builder/webpack/plugins/warnfix.mjs
similarity index 100%
rename from lib/builder/webpack/plugins/warnfix.js
rename to lib/builder/webpack/plugins/warnfix.mjs
diff --git a/lib/builder/webpack/postcss.js b/lib/builder/webpack/postcss.mjs
similarity index 81%
rename from lib/builder/webpack/postcss.js
rename to lib/builder/webpack/postcss.mjs
index a8488d996a..b789f1fd99 100644
--- a/lib/builder/webpack/postcss.js
+++ b/lib/builder/webpack/postcss.mjs
@@ -1,11 +1,11 @@
-import { existsSync } from 'fs'
-import { resolve, join } from 'path'
-import { cloneDeep } from 'lodash'
+import fs from 'fs'
+import path from 'path'
+import ـ from 'lodash'
 import { isPureObject } from '../../common/utils'
 import createResolver from 'postcss-import-resolver'
 
 export default function postcssConfig() {
-  let config = cloneDeep(this.options.build.postcss)
+  let config = ـ.cloneDeep(this.options.build.postcss)
 
   /* istanbul ignore if */
   if (!config) {
@@ -22,8 +22,8 @@ export default function postcssConfig() {
       '.postcssrc.json',
       '.postcssrc.yaml'
     ]) {
-      if (existsSync(resolve(dir, file))) {
-        const postcssConfigPath = resolve(dir, file)
+      if (fs.existsSync(path.resolve(dir, file))) {
+        const postcssConfigPath = path.resolve(dir, file)
         return {
           sourceMap: this.options.build.cssSourceMap,
           config: {
@@ -50,10 +50,10 @@ export default function postcssConfig() {
           'postcss-import': {
             resolve: createResolver({
               alias: {
-                '~': join(this.options.srcDir),
-                '~~': join(this.options.rootDir),
-                '@': join(this.options.srcDir),
-                '@@': join(this.options.rootDir)
+                '~': path.join(this.options.srcDir),
+                '~~': path.join(this.options.rootDir),
+                '@': path.join(this.options.srcDir),
+                '@@': path.join(this.options.rootDir)
               },
               modules: [
                 this.options.srcDir,
diff --git a/lib/builder/webpack/server.config.js b/lib/builder/webpack/server.config.mjs
similarity index 90%
rename from lib/builder/webpack/server.config.js
rename to lib/builder/webpack/server.config.mjs
index d91b146828..a92b6d7a18 100644
--- a/lib/builder/webpack/server.config.js
+++ b/lib/builder/webpack/server.config.mjs
@@ -2,10 +2,10 @@ import webpack from 'webpack'
 // import VueSSRServerPlugin from 'vue-server-renderer/server-plugin'
 import VueSSRServerPlugin from './plugins/vue/server'
 import nodeExternals from 'webpack-node-externals'
-import { each } from 'lodash'
-import { resolve } from 'path'
-import { existsSync } from 'fs'
-import base from './base.config.js'
+import _ from 'lodash'
+import path from 'path'
+import fs from 'fs'
+import base from './base.config'
 
 /*
 |--------------------------------------------------------------------------
@@ -17,7 +17,7 @@ export default function webpackServerConfig() {
 
   // Env object defined in nuxt.config.js
   let env = {}
-  each(this.options.env, (value, key) => {
+  _.each(this.options.env, (value, key) => {
     env['process.env.' + key] =
       ['boolean', 'number'].indexOf(typeof value) !== -1
         ? value
@@ -30,7 +30,7 @@ export default function webpackServerConfig() {
   config = Object.assign(config, {
     target: 'node',
     node: false,
-    entry: resolve(this.options.buildDir, 'server.js'),
+    entry: path.resolve(this.options.buildDir, 'server.js'),
     output: Object.assign({}, config.output, {
       filename: 'server-bundle.js',
       libraryTarget: 'commonjs2'
@@ -60,7 +60,7 @@ export default function webpackServerConfig() {
   // https://webpack.js.org/configuration/externals/#externals
   // https://github.com/liady/webpack-node-externals
   this.options.modulesDir.forEach(dir => {
-    if (existsSync(dir)) {
+    if (fs.existsSync(dir)) {
       config.externals.push(
         nodeExternals({
           // load non-javascript files with extensions, presumably via loaders
diff --git a/lib/builder/webpack/style-loader.js b/lib/builder/webpack/style-loader.js
index 9c5e2b500e..c7f15e3797 100644
--- a/lib/builder/webpack/style-loader.js
+++ b/lib/builder/webpack/style-loader.js
@@ -1,5 +1,5 @@
 import ExtractTextPlugin from 'extract-text-webpack-plugin'
-import { join } from 'path'
+import path from 'path'
 import postcssConfig from './postcss'
 
 export default function styleLoader(ext, loaders = [], isVueLoader = false) {
@@ -57,8 +57,8 @@ export default function styleLoader(ext, loaders = [], isVueLoader = false) {
   // css-loader
   // https://github.com/webpack-contrib/css-loader
   const cssLoaderAlias = {}
-  cssLoaderAlias[`/${this.options.dir.assets}`] = join(this.options.srcDir, this.options.dir.assets)
-  cssLoaderAlias[`/${this.options.dir.static}`] = join(this.options.srcDir, this.options.dir.static)
+  cssLoaderAlias[`/${this.options.dir.assets}`] = path.join(this.options.srcDir, this.options.dir.assets)
+  cssLoaderAlias[`/${this.options.dir.static}`] = path.join(this.options.srcDir, this.options.dir.static)
 
   loaders.unshift({
     loader: 'css-loader',
diff --git a/lib/builder/webpack/vue-loader.js b/lib/builder/webpack/vue-loader.mjs
similarity index 100%
rename from lib/builder/webpack/vue-loader.js
rename to lib/builder/webpack/vue-loader.mjs
diff --git a/lib/common/modes.js b/lib/common/modes.mjs
similarity index 100%
rename from lib/common/modes.js
rename to lib/common/modes.mjs
diff --git a/lib/common/nuxt.config.js b/lib/common/nuxt.config.js
index a1505263c8..8a30262ae5 100644
--- a/lib/common/nuxt.config.js
+++ b/lib/common/nuxt.config.js
@@ -1,4 +1,4 @@
-import { resolve } from 'path'
+import path from 'path'
 
 export default {
   mode: 'universal',
@@ -6,8 +6,8 @@ export default {
   debug: undefined, // Will be equal to dev if not provided
   buildDir: '.nuxt',
   cacheDir: '.cache',
-  nuxtDir: resolve(__dirname, '../..'),
-  nuxtAppDir: resolve(__dirname, '../app'),
+  nuxtDir: path.resolve(__dirname, '../..'),
+  nuxtAppDir: path.resolve(__dirname, '../app'),
   modulesDir: ['node_modules'], // ~> relative to options.rootDir
   ignorePrefix: '-',
   ignore: [
diff --git a/lib/common/options.js b/lib/common/options.mjs
similarity index 85%
rename from lib/common/options.js
rename to lib/common/options.mjs
index b3ecf1212b..e97411b773 100644
--- a/lib/common/options.js
+++ b/lib/common/options.mjs
@@ -1,7 +1,7 @@
 import _ from 'lodash'
 import Debug from 'debug'
-import { join, resolve } from 'path'
-import { existsSync, readdirSync } from 'fs'
+import path from 'path'
+import fs from 'fs'
 
 import { isUrl, isPureObject } from '../common/utils'
 
@@ -59,17 +59,17 @@ Options.from = function (_options) {
 
   // Resolve dirs
   options.srcDir = hasValue(options.srcDir)
-    ? resolve(options.rootDir, options.srcDir)
+    ? path.resolve(options.rootDir, options.srcDir)
     : options.rootDir
-  options.buildDir = resolve(options.rootDir, options.buildDir)
-  options.cacheDir = resolve(options.rootDir, options.cacheDir)
+  options.buildDir = path.resolve(options.rootDir, options.buildDir)
+  options.cacheDir = path.resolve(options.rootDir, options.cacheDir)
 
   // Populate modulesDir
   options.modulesDir = []
     .concat(options.modulesDir)
-    .concat(join(options.nuxtDir, 'node_modules'))
+    .concat(path.join(options.nuxtDir, 'node_modules'))
     .filter(dir => hasValue(dir))
-    .map(dir => resolve(options.rootDir, dir))
+    .map(dir => path.resolve(options.rootDir, dir))
 
   // Sanitize extensions
   if (options.extensions.indexOf('js') === -1) {
@@ -77,9 +77,9 @@ Options.from = function (_options) {
   }
 
   // If app.html is defined, set the template path to the user template
-  options.appTemplatePath = resolve(options.buildDir, 'views/app.template.html')
-  if (existsSync(join(options.srcDir, 'app.html'))) {
-    options.appTemplatePath = join(options.srcDir, 'app.html')
+  options.appTemplatePath = path.resolve(options.buildDir, 'views/app.template.html')
+  if (fs.existsSync(path.join(options.srcDir, 'app.html'))) {
+    options.appTemplatePath = path.join(options.srcDir, 'app.html')
   }
 
   // Ignore publicPath on dev
@@ -91,8 +91,8 @@ Options.from = function (_options) {
   // If store defined, update store options to true unless explicitly disabled
   if (
     options.store !== false &&
-    existsSync(join(options.srcDir, options.dir.store)) &&
-    readdirSync(join(options.srcDir, options.dir.store))
+    fs.existsSync(path.join(options.srcDir, options.dir.store)) &&
+    fs.readdirSync(path.join(options.srcDir, options.dir.store))
       .find(filename => filename !== 'README.md' && filename[0] !== '.')
   ) {
     options.store = true
diff --git a/lib/common/utils.js b/lib/common/utils.mjs
similarity index 93%
rename from lib/common/utils.js
rename to lib/common/utils.mjs
index fb3b55e2c8..e22d4eed3d 100644
--- a/lib/common/utils.js
+++ b/lib/common/utils.mjs
@@ -1,4 +1,4 @@
-import { resolve, relative, sep } from 'path'
+import path from 'path'
 import _ from 'lodash'
 import Chalk from 'chalk'
 import ORA from 'ora'
@@ -10,7 +10,7 @@ export const printWarn = function (msg, from) {
 }
 
 export const renderError = function (_error, from) {
-  const errStr = _error.toString()
+  const errStr = _error.stack
   const fromStr = from ? Chalk.red(` ${from}`) : ''
   return '\n' + Chalk.bgRed.black(' ERROR ') + fromStr + '\n\n' + errStr
 }
@@ -181,7 +181,7 @@ export const wChunk = function wChunk(p = '') {
 }
 
 const reqSep = /\//g
-const sysSep = _.escapeRegExp(sep)
+const sysSep = _.escapeRegExp(path.sep)
 const normalize = string => string.replace(reqSep, sysSep)
 
 export const r = function r() {
@@ -192,7 +192,7 @@ export const r = function r() {
     return wp(lastArg)
   }
 
-  return wp(resolve(...args.map(normalize)))
+  return wp(path.resolve(...args.map(normalize)))
 }
 
 export const relativeTo = function relativeTo() {
@@ -200,36 +200,37 @@ export const relativeTo = function relativeTo() {
   let dir = args.shift()
 
   // Resolve path
-  let path = r(...args)
+  let _path = r(...args)
 
   // Check if path is an alias
-  if (path.indexOf('@') === 0 || path.indexOf('~') === 0) {
-    return path
+  if (_path.indexOf('@') === 0 || _path.indexOf('~') === 0) {
+    return _path
   }
 
   // Make correct relative path
-  let rp = relative(dir, path)
+  let rp = path.relative(dir, _path)
   if (rp[0] !== '.') {
     rp = './' + rp
   }
+
   return wp(rp)
 }
 
-export const flatRoutes = function flatRoutes(router, path = '', routes = []) {
+export const flatRoutes = function flatRoutes(router, _path = '', routes = []) {
   router.forEach(r => {
     if (!r.path.includes(':') && !r.path.includes('*')) {
       /* istanbul ignore if */
       if (r.children) {
-        if (path === '' && r.path === '/') {
+        if (_path === '' && r.path === '/') {
           routes.push('/')
         }
-        flatRoutes(r.children, path + r.path + '/', routes)
+        flatRoutes(r.children, _path + r.path + '/', routes)
       } else {
-        path = path.replace(/^\/+$/, '/')
+        _path = _path.replace(/^\/+$/, '/')
         routes.push(
-          (r.path === '' && path[path.length - 1] === '/'
-            ? path.slice(0, -1)
-            : path) + r.path
+          (r.path === '' && _path[_path.length - 1] === '/'
+            ? _path.slice(0, -1)
+            : _path) + r.path
         )
       }
     }
diff --git a/lib/core/index.js b/lib/core/index.mjs
similarity index 100%
rename from lib/core/index.js
rename to lib/core/index.mjs
diff --git a/lib/core/meta.js b/lib/core/meta.mjs
similarity index 100%
rename from lib/core/meta.js
rename to lib/core/meta.mjs
diff --git a/lib/core/middleware/error.js b/lib/core/middleware/error.mjs
similarity index 88%
rename from lib/core/middleware/error.js
rename to lib/core/middleware/error.mjs
index 3b528992d6..39a8d60738 100644
--- a/lib/core/middleware/error.js
+++ b/lib/core/middleware/error.mjs
@@ -1,6 +1,6 @@
 import Youch from '@nuxtjs/youch'
-import { join, resolve, relative, isAbsolute } from 'path'
-import { readFile } from 'fs-extra'
+import path from 'path'
+import fs from 'fs-extra'
 
 export default function errorMiddleware(err, req, res, next) {
   // ensure statusCode, message and name fields
@@ -83,20 +83,20 @@ async function readSource(frame) {
   const searchPath = [
     this.options.srcDir,
     this.options.rootDir,
-    join(this.options.buildDir, 'dist'),
+    path.join(this.options.buildDir, 'dist'),
     this.options.buildDir,
     process.cwd()
   ]
 
   // Scan filesystem for real source
   for (let pathDir of searchPath) {
-    let fullPath = resolve(pathDir, frame.fileName)
-    let source = await readFile(fullPath, 'utf-8').catch(() => null)
+    let fullPath = path.resolve(pathDir, frame.fileName)
+    let source = await fs.readFile(fullPath, 'utf-8').catch(() => null)
     if (source) {
       frame.contents = source
       frame.fullPath = fullPath
-      if (isAbsolute(frame.fileName)) {
-        frame.fileName = relative(this.options.rootDir, fullPath)
+      if (path.isAbsolute(frame.fileName)) {
+        frame.fileName = path.relative(this.options.rootDir, fullPath)
       }
       return
     }
diff --git a/lib/core/middleware/nuxt.js b/lib/core/middleware/nuxt.mjs
similarity index 100%
rename from lib/core/middleware/nuxt.js
rename to lib/core/middleware/nuxt.mjs
diff --git a/lib/core/module.js b/lib/core/module.mjs
similarity index 100%
rename from lib/core/module.js
rename to lib/core/module.mjs
diff --git a/lib/core/nuxt.js b/lib/core/nuxt.mjs
similarity index 82%
rename from lib/core/nuxt.js
rename to lib/core/nuxt.mjs
index ac6df46298..97add02345 100644
--- a/lib/core/nuxt.js
+++ b/lib/core/nuxt.mjs
@@ -1,16 +1,16 @@
 import Debug from 'debug'
 import enableDestroy from 'server-destroy'
 import Module from 'module'
-import { isPlainObject } from 'lodash'
+import _ from 'lodash'
 import chalk from 'chalk'
-import { existsSync } from 'fs-extra'
+import fs from 'fs-extra'
+import path from 'path'
 import Options from '../common/options'
 import { sequence, printError } from '../common/utils'
-import { resolve, join } from 'path'
-import { version } from '../../package.json'
+import packageJSON from '../../package.json'
 import ModuleContainer from './module'
 import Renderer from './renderer'
-import { requireModule } from '../common/module'
+import moduleUtil from '../common/module'
 
 const debug = Debug('nuxt:')
 debug.color = 5
@@ -42,7 +42,7 @@ export default class Nuxt {
   }
 
   static get version() {
-    return version
+    return packageJSON.version
   }
 
   async ready() {
@@ -51,7 +51,7 @@ export default class Nuxt {
     }
 
     // Add hooks
-    if (isPlainObject(this.options.hooks)) {
+    if (_.isPlainObject(this.options.hooks)) {
       this.addObjectHooks(this.options.hooks)
     } else if (typeof this.options.hooks === 'function') {
       this.options.hooks(this.hook)
@@ -157,22 +157,22 @@ export default class Nuxt {
     })
   }
 
-  resolveAlias(path) {
-    if (path.indexOf('@@') === 0 || path.indexOf('~~') === 0) {
-      return join(this.options.rootDir, path.substr(2))
+  resolveAlias(_path) {
+    if (_path.indexOf('@@') === 0 || _path.indexOf('~~') === 0) {
+      return path.join(this.options.rootDir, _path.substr(2))
     }
 
-    if (path.indexOf('@') === 0 || path.indexOf('~') === 0) {
-      return join(this.options.srcDir, path.substr(1))
+    if (_path.indexOf('@') === 0 || _path.indexOf('~') === 0) {
+      return path.join(this.options.srcDir, _path.substr(1))
     }
 
-    return resolve(this.options.srcDir, path)
+    return path.resolve(this.options.srcDir, _path)
   }
 
-  resolvePath(path) {
+  resolvePath(_path) {
     // Try to resolve using NPM resolve path first
     try {
-      const resolvedPath = Module._resolveFilename(path, {
+      const resolvedPath = Module._resolveFilename(_path, {
         paths: this.options.modulesDir
       })
       return resolvedPath
@@ -182,23 +182,23 @@ export default class Nuxt {
       }
     }
 
-    let _path = this.resolveAlias(path)
+    let __path = this.resolveAlias(_path)
 
-    if (existsSync(_path)) {
-      return _path
+    if (fs.existsSync(__path)) {
+      return __path
     }
 
     for (let ext of this.options.extensions) {
-      if (existsSync(_path + '.' + ext)) {
+      if (fs.existsSync(_path + '.' + ext)) {
         return _path + '.' + ext
       }
     }
 
-    throw new Error(`Cannot resolve "${path}" from "${_path}"`)
+    throw new Error(`Cannot resolve "${_path}" from "${__path}"`)
   }
 
   requireModule(name) {
-    return requireModule(this.resolvePath(name))
+    return moduleUtil.requireModule(this.resolvePath(name))
   }
 
   async close(callback) {
diff --git a/lib/core/renderer.js b/lib/core/renderer.mjs
similarity index 94%
rename from lib/core/renderer.js
rename to lib/core/renderer.mjs
index 396e59f45b..203e6cbfa2 100644
--- a/lib/core/renderer.js
+++ b/lib/core/renderer.mjs
@@ -3,9 +3,9 @@ import serialize from 'serialize-javascript'
 import serveStatic from 'serve-static'
 import compression from 'compression'
 import _ from 'lodash'
-import { join, resolve } from 'path'
+import path from 'path'
 import fs from 'fs-extra'
-import { createBundleRenderer } from 'vue-server-renderer'
+import vueServerRenderer from 'vue-server-renderer'
 import Debug from 'debug'
 import connect from 'connect'
 import launchMiddleware from 'launch-editor-middleware'
@@ -66,18 +66,18 @@ export default class Renderer {
   }
 
   async loadResources(_fs = fs) {
-    let distPath = resolve(this.options.buildDir, 'dist')
+    let distPath = path.resolve(this.options.buildDir, 'dist')
     let updated = []
 
     resourceMap.forEach(({ key, fileName, transform }) => {
       let rawKey = '$$' + key
-      const path = join(distPath, fileName)
+      const _path = path.join(distPath, fileName)
 
       let rawData, data
-      if (!_fs.existsSync(path)) {
+      if (!_fs.existsSync(_path)) {
         return // Resource not exists
       }
-      rawData = _fs.readFileSync(path, 'utf8')
+      rawData = _fs.readFileSync(_path, 'utf8')
       if (!rawData || rawData === this.resources[rawKey]) {
         return // No changes
       }
@@ -92,7 +92,7 @@ export default class Renderer {
     })
 
     // Reload error template
-    const errorTemplatePath = resolve(this.options.buildDir, 'views/error.html')
+    const errorTemplatePath = path.resolve(this.options.buildDir, 'views/error.html')
     if (fs.existsSync(errorTemplatePath)) {
       this.resources.errorTemplate = parseTemplate(
         fs.readFileSync(errorTemplatePath, 'utf8')
@@ -100,7 +100,7 @@ export default class Renderer {
     }
 
     // Load loading template
-    const loadingHTMLPath = resolve(this.options.buildDir, 'loading.html')
+    const loadingHTMLPath = path.resolve(this.options.buildDir, 'loading.html')
     if (fs.existsSync(loadingHTMLPath)) {
       this.resources.loadingHTML = fs.readFileSync(loadingHTMLPath, 'utf8')
       this.resources.loadingHTML = this.resources.loadingHTML.replace(
@@ -162,7 +162,7 @@ export default class Renderer {
     }
 
     // Create bundle renderer for SSR
-    this.bundleRenderer = createBundleRenderer(
+    this.bundleRenderer = vueServerRenderer.createBundleRenderer(
       this.resources.serverBundle,
       Object.assign(
         {
@@ -248,7 +248,7 @@ export default class Renderer {
 
     // For serving static/ files to /
     const staticMiddleware = serveStatic(
-      resolve(this.options.srcDir, this.options.dir.static),
+      path.resolve(this.options.srcDir, this.options.dir.static),
       this.options.render.static
     )
     staticMiddleware.prefix = this.options.render.static.prefix
@@ -257,7 +257,7 @@ export default class Renderer {
     // Serve .nuxt/dist/ files only for production
     // For dev they will be served with devMiddleware
     if (!this.options.dev) {
-      const distDir = resolve(this.options.buildDir, 'dist')
+      const distDir = path.resolve(this.options.buildDir, 'dist')
       this.useMiddleware({
         path: this.publicPath,
         handler: serveStatic(distDir, {
@@ -401,7 +401,7 @@ export default class Renderer {
     /* istanbul ignore if */
     if (!jsdom) {
       try {
-        jsdom = require('jsdom')
+        jsdom = this.nuxt.requireModule('jsdom')
       } catch (e) /* istanbul ignore next */ {
         /* eslint-disable no-console */
         console.error('Fail when calling nuxt.renderAndGetWindow(url)')