webpack 貌似把style-loader打进去了。。。

Question

这是我的 webpack 配置

const path = require('path')
const CleanWebpackPlugin = require('clean-webpack-plugin')
const HtmlWebpackPlugin = require('html-webpack-plugin')
const pkg = require('../package.json')
const webpack = require('webpack')
const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin

module.exports = {
  context: path.resolve(__dirname, '../'),
  mode: 'development',
  target: 'web',
  entry: {
    app: './src/main.js'
  },
  output: {
    filename: 'js/[name].bundle.js',
    path: path.resolve('./dist'),
    publicPath: '/'
  },
  resolve: {
    // modules: [
    //   path.resolve('./src'),
    //   'node_modules'
    // ],
    alias: {
      '@': path.resolve('./src')
    },
    extensions: ['.js', '.vue', '.json']
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        include: [path.resolve('./src')],
        loader: 'babel-loader'
      },
      {
        test: /\.js$/,
        include: [path.resolve('./src')],
        enforce: 'pre',
        loader: 'eslint-loader',
        options: {
          formatter: require('eslint-friendly-formatter'),
          emitError: true
        }
      },
      {
        test: /\.css$/,
        use: [
          {
            loader: 'style-loader',
            options: {
              sourceMap: true
            }
          },
          {
            loader: 'css-loader',
            options: {
              sourceMap: true,
              importLoaders: 1
            }
          },
          {
            loader: 'postcss-loader',
            options: {
              sourceMap: true
            }
          }
        ]
      },
      {
        test: /\.(png|jpe?g|gif|svg)$/,
        loader: 'url-loader',
        options: {
          limit: 8192,
          name: 'images/[name].[hash:5].[ext]'
        }
      },
      {
        test: /\.(woff2?|eot|ttf|otf)(\?.*)?$/,
        loader: 'url-loader',
        options: {
          limit: 10240,
          name: 'fonts/[name].[hash:5].[ext]'
        }
      }
    ]
  },
  devServer: {
    contentBase: path.resolve('static'),
    publicPath: '/',
    compress: true,
    hot: true,
    open: true,
    overlay: true,
    port: 9999,
    clientLogLevel: 'warning',
    proxy: {}
  },
  plugins: [
    new CleanWebpackPlugin([path.resolve('./dist')], {
      root: path.resolve('./')
    }),
    new HtmlWebpackPlugin({
      title: pkg.name,
      filename: 'index.html',
      template: path.resolve('index.html')
    }),
    new webpack.HotModuleReplacementPlugin(),
    new BundleAnalyzerPlugin()
  ],
  devtool: 'cheap-eval-source-map'
}

在打包后用 analyzer 分析的时候为什么会把 style-loader 和 css-loader 也打进去了。。。。导致文件特别大 😂

"webpack": "^4.12.2",
"webpack-cli": "^3.0.8"

package.json

{
  "name": "bundletask",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "build": "webpack --display --config ./build/webpack.config.js",
    "dev": "webpack-dev-server --inline --progress --color --config ./build/webpack.config.js"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "autoprefixer": "^8.6.4",
    "babel-core": "^6.26.3",
    "babel-eslint": "^8.2.5",
    "babel-loader": "^7.1.4",
    "babel-plugin-transform-runtime": "^6.23.0",
    "babel-preset-env": "^1.7.0",
    "babel-preset-stage-2": "^6.24.1",
    "chalk": "^2.4.1",
    "clean-webpack-plugin": "^0.1.19",
    "css-loader": "^0.28.11",
    "eslint": "^5.0.1",
    "eslint-config-standard": "^11.0.0",
    "eslint-friendly-formatter": "^4.0.1",
    "eslint-loader": "^2.0.0",
    "eslint-plugin-import": "^2.13.0",
    "eslint-plugin-node": "^6.0.1",
    "eslint-plugin-promise": "^3.8.0",
    "eslint-plugin-standard": "^3.1.0",
    "file-loader": "^1.1.11",
    "html-webpack-plugin": "^3.2.0",
    "postcss-loader": "^2.1.5",
    "style-loader": "^0.21.0",
    "url-loader": "^1.0.1",
    "webpack": "^4.12.2",
    "webpack-bundle-analyzer": "^2.13.1",
    "webpack-cli": "^3.0.8",
    "webpack-dev-server": "^3.1.4"
  }
}

Answer 1

你没有使用插件把 css 单独打成一个文件，所以样式是通过 js 动态创建 style 标签插入页面的，你觉得这部分代码是哪来的？就是 style-loader！所以这种方式是会把 style-loader 打进去来完成动态创建 style 标签引入样式的功能。你可以选择使用 mini-css-extract-plugin 插件将 css 单独提取为一个文件来避免此问题，这一步都是产品模式下配置的。此外，在开发模式下分析 bundle 没什么意义。

Answer 2

在pkg.json里面是不是把style-loader和cssloader放dependence里面了？这两个东西应该在dev-dependece里面。
另外，你webpack里面配置的mode就是'development'，所以打进去也理所应当。

---

看到你贴的pkg.json了，大兄弟，你只有个devdependence，而且webpack里面配置的mode就是'development'，打包当然就打包这个啦。

建议你去学学webpack基础的东西。不然你不会明白的。

Answer 3

你的package.json 贴一下