Webpack 5 不输出 LESS 样式？

问题描述

我正在尝试将我的所有依赖项升级到最新版本，但除 webpack 5 之外的所有内容都没有按预期工作。问题是我的 less 样式根本没有加载。运行 prod 构建时，dist 文件夹中没有输出的 less 文件，并且 localhost dev 页面中没有样式。我已经翻遍了他们的文档，并尽可能地模仿了这些示例。

节点 14.15.4

webpack.config.js

const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const TerserJSPlugin = require('terser-webpack-plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const CssMinimizerPlugin = require('css-minimizer-webpack-plugin');
const webpack = require('webpack');
const packageJson = require('./package.json');

const ENV = process.env.NODE_ENV || 'production';
const isDev = process.env.NODE_ENV !== 'production';
console.log('isDev',isDev);

module.exports = {
    entry: {
        [`${packageJson.name}.${packageJson.version}`]: './src/index.js'
    },optimization: {
        minimizer: [
            new TerserJSPlugin({
                terserOptions: {
                    output: {
                        comments: false,},extractComments: false,}),new CssMinimizerPlugin({
                minimizerOptions: {
                    preset: [
                        'default',{
                            discardComments: { removeAll: true },],splitChunks: {
            cacheGroups: {
                styles: {
                    idHint: `${packageJson.name}.${packageJson.version}`,type: 'css/mini-extract',chunks: 'all',enforce: true,module: {
        rules: [
            {
                test: /\.js$/,exclude: /node_modules/,use: {
                    loader: 'babel-loader'
                }
            },{
                test: /\.(le|c)ss$/,use: [
                    isDev ? 'style-loader' : MiniCssExtractPlugin.loader,'css-loader','less-loader',}
        ]
    },plugins: [
        new MiniCssExtractPlugin({
            filename: '[name].min.css',chunkFilename: '[name].min.css',new HtmlWebpackPlugin({
            template: 'src/index.html',minify: {
                removeComments: true,collapseWhitespace: true,removeRedundantAttributes: true,useShortDoctype: true,removeEmptyAttributes: true,removeStyleLinkTypeAttributes: true,keepClosingSlash: true,minifyJS: true,minifyCSS: true,minifyURLs: true,new webpack.DefinePlugin({
            // PRODUCTION: JSON.stringify(ENV) === 'production','process.env.NODE_ENV': JSON.stringify(ENV)
        }),new webpack.IgnorePlugin({ resourceRegExp: /^\.\/locale$/ })
    ],output: {
        filename: '[name].min.js',devServer: {
        port: 3000
    }
};

package.json

{
  "scripts": {
    "build": "NODE_ENV=production webpack --mode=production","dev": "clear && webpack serve --open --mode=development","devDependencies": {
    "@babel/cli": "^7.12.13","@babel/core": "^7.12.13","@babel/plugin-proposal-class-properties": "^7.12.13","@babel/plugin-proposal-object-rest-spread": "^7.12.13","@babel/plugin-proposal-optional-chaining": "^7.12.13","@babel/plugin-transform-runtime": "^7.12.15","@babel/preset-env": "^7.12.13","@babel/preset-flow": "^7.12.13","@babel/preset-react": "^7.12.13","babel-loader": "8.2.2","babelify": "10.0.0","css-loader": "5.0.2","css-minimizer-webpack-plugin": "^1.2.0","html-webpack-plugin": "5.0.0","less": "4.1.1","less-loader": "^8.0.0","mini-css-extract-plugin": "^1.3.6","style-loader": "2.0.0","terser-webpack-plugin": "^5.1.1","webpack": "^5.21.2","webpack-cli": "4.5.0","webpack-dev-server": "^3.11.2"
  },"dependencies": {
    "react": "^17.0.1","react-dom": "^17.0.1"
  },}

App.js

import React from 'react';
import './App.less';

const App = () => (
  <div className="App">
    ...
  </div>
);

export default App;

解决方法

我需要从 package.json 中删除 "sideEffects": false。查看 github 线程 here