Webpackプラグインのclean-webpack-pluginファイルをクリア

const path = require('path');
// html
const htmlWebpackPlugin = require('html-webpack-plugin');
// css  
const ExtractTextPlugin = require("extract-text-webpack-plugin");
//     
const CleanWebpackPlugin = require('clean-webpack-plugin');
module.exports = {
    //   
    mode: 'production',
    //     
    entry: {
        'app': './src/app.js'
    },
    //     
    output: {
        //       
        path: path.resolve(__dirname, 'dist'),
        //        
        filename: '[name].[chunkhash].js'
    },
    //   loader  webpack4.0  
    module: {
        rules: [
            //    css-loader 
            {
                test: /\.css$/,
                include: [
                    path.resolve(__dirname, 'src')
                ],
                // loader: ['style-loader', 'css-loader'],
                use: ExtractTextPlugin.extract({
                    fallback: "style-loader",
                    use: "css-loader"
                }),
                //   node_modules  
                exclude: [
                    path.resolve(__dirname, "node_modules")
                ]
            },
            {
                test: /\.scss$/,
                include: [
                    path.resolve(__dirname, 'src')
                ],
                // loader: ['style-loader', 'css-loader', 'sass-loader'],
                use: ExtractTextPlugin.extract({
                    fallback: "style-loader",
                    use: ["css-loader", "sass-loader"]
                }),
                exclude: [
                    path.resolve(__dirname, "node_modules")
                ]
            }
        ]
    },
    // server   
    devServer: {
        port: 8848,
        open: false
    },
    //   
    plugins: [
        // 
        new htmlWebpackPlugin({
            //   
            title: '   webpack',
            //   
            template: 'src/index.html',
            //          
            minify: {
                collapseWhitespace: true //false | true
            },
            //   hash
            hash: true
        }),
        // css  
        new ExtractTextPlugin('style.css'),
        //           
        new CleanWebpackPlugin(['dist']),
    ]
}