vue-cli#webpack3.0 升级到webpack4.6

全局下载安装webpack-cli

npm i webpack-cli -g

再当前项目中安装下面包

npm i [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] -D

这个时候通过npm run dev可能会出现下面错误

如果出现上面的错误，则通过npm安装下面包（主要是针对开通了eslint的情况需要更新eslint版本）

npm i [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] -D

再次运行可能会出现下面错误

如果出现上面的错误，则需要在webppack中配置(vue-loader 15版本需要)：

// webpack.config.js
const { VueLoaderPlugin } = require('vue-loader')
module.exports = {
  // ...
  plugins: [
    new VueLoaderPlugin()
  ]
}

下面开始就是关于webpack的一些配置了

需要对开发环境加上

mode: 'development'

需要对生产环境加上

mode: 'production'

将开发环境下面的两个插件去掉，因为webpack默认设置了

new webpack.NamedModulesPlugin()
new webpack.NoEmitOnErrorsPlugin()

将生产环境下面的commonschunkplugin插件配置全部去掉

new webpack.optimize.CommonsChunkPlugin({
      name: 'vendor',
      minChunks (module) {
        // any required modules inside node_modules are extracted to vendor
        return (
          module.resource &&
          /\.js$/.test(module.resource) &&
          module.resource.indexOf(
            path.join(__dirname, '../node_modules')
          ) === 0
        )
      }
    }),
    new webpack.optimize.CommonsChunkPlugin({
      name: 'manifest',
      minChunks: Infinity
    }),
    new webpack.optimize.CommonsChunkPlugin({
      name: 'app',
      async: 'vendor-async',
      children: true,
      minChunks: 3
    }),

然后加上下面的配置

optimization: {
    runtimeChunk: {
      name: 'manifest'
    },
    splitChunks: {
      cacheGroups: {
        vendor: {
          test: /[\\/]node_modules[\\/]/,
          name: 'vendor',
          chunks: 'all'
        },
        'async-vendors': {
          test: /[\\/]node_modules[\\/]/,
          minChunks: 2,
          chunks: 'async',
          name: 'async-vendors'
        }
      }
    }
  }

npm run build如果出现下面的错误

则需要将下面的配置

new ExtractTextPlugin({
  filename: utils.assetsPath('css/[name].[contenthash].css'),
  allChunks: true
}),

改成

new ExtractTextPlugin({
  filename: utils.assetsPath('css/[name].[md5:contenthash].css'),
  allChunks: true
}),

如果项目中原来使用了lodash,而且通过lodash-webpack-plugin进行按需加载的话，可能会出现下面的问题

如果出现了话，就将在webpack中下面配置的options整个去掉

{
    test: /\.js$/,
    loader: 'babel-loader',
    options: {
      plugins: ['lodash'],
      presets: [['env', { modules: false, targets: { node: 4 } }]]
    },
    exclude: /node_modules/,
    include: [resolve('src'), resolve('test')]
},

然后在.babelrc中的plugins中增加lodash

{
  "presets": [
    ["env", {
      "modules": false,
      "targets": {
        "browsers": ["> 1%", "last 2 versions", "not ie <= 8"]
      }
    }],
    "stage-2"
  ],
  "plugins": ["transform-vue-jsx", "transform-runtime", "lodash"],
  "env": {
    "test": {
      "presets": ["env", "stage-2"],
      "plugins": ["transform-vue-jsx", "istanbul"]
    }
  }
}

这样就大功告成了。