babel 7.x 和 webpack 4.x 配置vue项目

很偶然的今天想开个自己的小项目，记录一下最近项目工程上实现的一个小交互。按照之前运行非常流畅的配置走一遍，打包遇到各种坑。只好根据命令行的报错逐个排查，发现babel升级了一个大版本，已经到7.x了。看来每日沉迷项目，已经跟不上节奏了。这里记录一下遇到的问题以及解决方案。

1.webpack 4.x 插件 extract-text-webpack-plugin

(node:2628) DeprecationWarning: Tapable.plugin is deprecated. Use new API on `.hooks` instead
i ｢wds｣: Project is running at http://localhost:8300/
i ｢wds｣: webpack output is served from /
i ｢wds｣: Content not from webpack is served from F:\private\plugin-insert\dist
F:\private\plugin-insert\node_modules\webpack\lib\Chunk.js:838
                throw new Error(
                ^

Error: Chunk.entrypoints: Use Chunks.groupsIterable and filter by instanceof Entrypoint instead
    at Chunk.get (F:\private\plugin-insert\node_modules\webpack\lib\Chunk.js:838:9)
    at F:\private\plugin-insert\node_modules\extract-text-webpack-plugin\dist\index.js:176:48
    at Array.forEach (<anonymous>)
    at F:\private\plugin-insert\node_modules\extract-text-webpack-plugin\dist\index.js:171:18
    at AsyncSeriesHook.eval [as callAsync] (eval at create (F:\private\plugin-insert\node_modules\tapable\lib\HookCodeFactory.js:32:10), <anonymous>:7:1)
    at AsyncSeriesHook.lazyCompileHook (F:\private\plugin-insert\node_modules\tapable\lib\Hook.js:154:20)
    at Compilation.seal (F:\private\plugin-insert\node_modules\webpack\lib\Compilation.js:1231:27)
    at hooks.make.callAsync.err (F:\private\plugin-insert\node_modules\webpack\lib\Compiler.js:541:17)
    at _done (eval at create (F:\private\plugin-insert\node_modules\tapable\lib\HookCodeFactory.js:32:10), <anonymous>:9:1)
    at _err1 (eval at create (F:\private\plugin-insert\node_modules\tapable\lib\HookCodeFactory.js:32:10), <anonymous>:32:22)

extract-text-webpack-plugin 提取单独打包css文件时报错，官方安装部分的文档只写到了webpack 3，目前还没有webpack 4版本，可以使用 extract-text-webpack-plugin@next 解决，也可以使用 mini-css-extract-plugin 。

mini-css-extract-plugin 插件用法如下：

const MiniCssExtractPlugin = require("mini-css-extract-plugin") ;

const config = module.exports = {

 　　plugins: [
    　　  new MiniCssExtractPlugin({
      　　  filename: "[name].[chunkhash:8].css",
     　　   chunkFilename: "[id].css"
   　　   })
　　  ],

  　　module: {
    　　rules: [
     　　 {
      　　  test: /\.css$/,
      　　  use: [
        　　  　　MiniCssExtractPlugin.loader,
        　　 　　 "css-loader"
       　　 ]
    　　  }
  　　  ]
 　　 }
}

module.exports = config

2.babel 升级 6.x 到 7.x

(1) @babel/core

Module build failed (from ./node_modules/babel-loader/lib/index.js):
Error: Cannot find module '@babel/core'
 babel-loader@8 requires Babel 7.x (the package '@babel/core'). 
 If you'd like to use Babel 6.x ('babel-core'), you should install 'babel-loader@7'.

没找到 @babel/core ，这里把 babel-core 卸载，并安装 @babel/core 。

npm un babel-core
npm i -D @babel/core

(2) @babel/preset-*

Module build failed (from ./node_modules/babel-loader/lib/index.js):
Error: Plugin/Preset files are not allowed to export objects, only functions.

将 babel-preset-* 卸载，重新安装 @babel/preset-* ，并且修改 .babelrc 中的 presets

npm:
- babel-preset-env
+ @babel/perset-env

.babelrc:
- "presets": ["env"]
+ "presets": ["@babel/preset-env"]

另，stage-*已弃用

(3) @babel/plugin-*

Module build failed (from ./node_modules/babel-loader/lib/index.js):
TypeError: this.setDynamic is not a function
    at PluginPass.pre
    ...

这次是插件了，一样把babel-plugin-*卸载，重新安装@babel/plugin-*

然后修改.babelrc文件

具体的包名可以在 npm仓库 里找

(4) 最终文件

.babelrc

{
    "presets": ["@babel/preset-env"],
    "plugins": [
            "@babel/plugin-transform-runtime"
    ]
}

package.json

"devDependencies": {
    "@babel/core": "^7.1.2",
    "@babel/plugin-transform-runtime": "^7.1.0",
    "@babel/preset-env": "^7.1.0",
    "babel-loader": "^8.0.4"，
    
    ...
  },
"dependencies": {
    "@babel/runtime": "^7.1.2",
    "vue": "^2.5.17",
    "vue-loader": "^15.4.2",
    "vue-router": "^3.0.1",
    "vuex": "^3.0.1",
    "webpack": "^4.22.0",
    "webpack-cli": "^3.1.2",
    "webpack-dev-server": "^3.1.10",
    "webpack-merge": "^4.1.4"
    ...
  }

(5) 总结

babel 舍弃了以前的 babel-*-* 的命名方式，改成了 @babel/*-*

修改依赖和 .babelrc 文件后就能正常启动项目了。

3.vue-loader 15.x vueLoaderPlugin

vue-loader was used without the corresponding plugin. 
Make sure to include VueLoaderPlugin in your webpack config.

//两个方式都可以的，随便用一个

const VueLoaderPlugin = require('vue-loader/lib/plugin');

// 或者 

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


plugins: [
    // make sure to include the plugin for the magic
    new VueLoaderPlugin()
]

参考资料

升级指南 Upgrade to Babel 7

Setting up a Vue.js Project with webpack 4 and Babel 7

使用 Webpack 4 和 Babel 7 从头开始创建 React 应用程序