webpack.config.js

const path = require('path');

module.exports = async ({config}) => {
    // Overwrite the default storybook webpack config for same tests loaders are applied serially
    config.module.rules = [
        {
            test: /\.vue$/,
            loader: 'vue-loader'
        },
        {
            test: /\.js$/,
            loader: 'babel-loader',
            exclude: /node_modules/
        },
        {
            test: /\.(scss|css)$/,
            use: ['style-loader', 'css-loader', {
                loader: 'sass-loader',
                options: {
                    additionalData: '$sass-env: development;'
                }
            }],
            include: path.resolve(__dirname, '../')
        },
        {
            test: /\.pug$/,
            loader: 'pug-plain-loader'
        },
        {
            test: /\.(png|jpg|gif)$/,
            use: ['file-loader']
        }
    ];

    return config;
}