webpack.config.js

const path = require('path');
const CircularDependencyPlugin = require('circular-dependency-plugin');

module.exports = {
    entry: path.resolve(__dirname, './src/app.js'),
    module: {
        rules: [
            {
                test: /\.(js|jsx)$/,
                exclude: /node_modules/,
                use: ['babel-loader'],
            },{
                test: /\.s[ac]ss$/i,
                use: [
                    // Creates `style` nodes from JS strings
                    "style-loader",
                    // Translates CSS into CommonJS
                    "css-loader",
                    // Compiles Sass to CSS
                    "sass-loader",
                ],
            },
        ],
    },
    plugins: [
        new CircularDependencyPlugin({
            // exclude detection of files based on a RegExp
            exclude: /a\.js|node_modules/,
            // include specific files based on a RegExp
            include: /src/,
            // add errors to webpack instead of warnings
            failOnError: true,
            // allow import cycles that include an asyncronous import,
            // e.g. via import(/* webpackMode: "weak" */ './file.js')
            allowAsyncCycles: false,
            // set the current working directory for displaying module paths
            cwd: process.cwd(),
        })
    ],
    resolve: {
        extensions: ['*', '.js', '.jsx'],
    },
    output: {
        path: path.resolve(__dirname, './dist'),
        filename: 'app.js',
    },
    devServer: {
        contentBase: path.resolve(__dirname, './dist')
    },
};