Webpack 4 css模块TypeError：无法读取未定义的属性“上下文”

Posted 2023-02-22

【中文标题】Webpack 4 css模块TypeError：无法读取未定义的属性“上下文”

【英文标题】：Webpack 4 css modules TypeError: Cannot read property 'context' of undefined

【发布时间】：2018-10-29 08:12:57

【问题描述】：

我刚刚升级到 webpack 4。我使用 css 模块。

错误：

./client/src/common/accordian-component/accordian.css 中的错误 (./node_modules/css-loader??ref--5-1!./node_modules/postcss-loader/lib??ref--5-2!./client/src/common/accordian-component/accordian.css ) 模块构建失败：TypeError：无法读取属性“上下文” 在对象未定义。 （/Users/phillipjones/Workspace/sl_pathfinder/website/node_modules/css-loader/lib/loader.js:101:57） 在 Array.map() 处对象。 （/Users/phillipjones/Workspace/sl_pathfinder/website/node_modules/css-loader/lib/loader.js:99:31） 在 /Users/phillipjones/Workspace/sl_pathfinder/website/node_modules/css-loader/lib/processCss.js:200:3 来自之前的活动：在 Promise.then （/Users/phillipjones/Workspace/sl_pathfinder/website/node_modules/cls-bluebird/lib/shimMethod.js:38:20）在 Object.loader (/Users/phillipjones/Workspace/sl_pathfinder/website/node_modules/postcss-loader/lib/index.js:96:6) @ ./client/src/common/accordian-component/accordian.css 2:14-160 21:1-42:3 21:158-42:2 22:19-165 @ ./client/src/common/accordian-component/accordian-item.jsx @ ./client/src/common/accordian-component/all-components.js @ ./client/src/common/accordian-component/accordian-component.jsx @ ./client/src/common/index.js @ ./client/src/views/main-view/all-components.js @ ./client/src/views/main-view/main-view.jsx @ ./client/src/views/index.js @ ./client/src/routes/index.jsx @ ./client/src/App.jsx@多./client/src/App.jsx

webpack.config.js

require('dotenv').config();
const path = require('path');
const webpack = require('webpack');
const autoprefixer = require('autoprefixer');
const importPlugin = require('postcss-import');
const postcssFunctions = require('postcss-functions')(
  functions: require('./postcss-functions') ); // eslint-disable-line
// const fs = require('fs');
// const ExtractTextPlugin = require('extract-text-webpack-plugin');

const nodeEnv = process.env.NODE_ENV || 'development';
// console.log( nodeEnv );
let mode = 'production';
if (nodeEnv !== 'production') 
  mode = 'development';

// const api_base_url = process.env.API_BASE_URL || 'http://localhost:8000/api';

// Common rules
const rules = [
  
    test: /\.jsx?$/,
    use: ['babel-loader'],
    include: /(pathfinder-common|src)/,
  ,
  
    test: /\.css$/i,
    include: /client/,
    use: [
      'style-loader',
       loader: 'css-loader',
        options: 
          sourceMap: true,
          modules: true,
          importLoaders: 1,
          camelCase: true,
          localIdentName: '[name]__[local]___[hash:base64:5]',
        ,
      ,
      
        loader: 'postcss-loader',
        options: 
          plugins: [
            importPlugin(),
            autoprefixer( browsers: ['last 2 versions'] ),
            postcssFunctions,
          ],
        ,
      ,
    ],
  ,
  
    test: /\.woff2?/,
    loader: 'url-loader',
    options: 
      name: '[path][name].[ext]?[hash]',
      mimetype: 'application/font-woff',
    ,
  ,
  
    test: /\.(jpe?g|gif|svg|ico|ttf|otf|woff|woff2)(\?[a-z0-9=&.]+)?$/i,
    loader: 'url-loader',
    options: 
      name: '[path][name].[ext]?[hash]',
    ,
  ,

  
    test: /\.png$/,
    loader: 'url-loader?mimetype=image/png',
    options: 
      name: '[path][name].[ext]?[hash]',
    ,
  ,
];

module.exports = 
  mode,
  context: __dirname,
  devtool: 'cheap-module-source-map',
  entry: ['./client/src/App.jsx'],
  output: 
    path: path.resolve(__dirname, './client/public'),
    filename: 'bundle.js',
  ,
  resolve: 
    extensions: ['.js', '.jsx', '.json'],
    modules: [path.resolve(__dirname, 'node_modules')],
    symlinks: true,
  ,
  plugins: [
    // new ExtractTextPlugin('ml-common.css'),
    new webpack.optimize.OccurrenceOrderPlugin(),
    // new webpack.HotModuleReplacementPlugin(),
    new webpack.NoEmitOnErrorsPlugin(),
    new webpack.DefinePlugin( 'process.env': 
      NODE_ENV: JSON.stringify(process.env.NODE_ENV)  ),
  ],
  module: 
    rules,
  ,
  devServer: 
    contentBase: path.resolve(__dirname, './client/public'),
    hot: true,
    quiet: false,
    noInfo: false,
    publicPath: 'http://localhost:8000',
    overlay: 
      warnings: true,
      errors: true,
    ,
  ,
;

【参考方案1】：

升级了 css-loader 并且成功了

"css-loader": "^0.28.11",