webpack.config.js

var path = require('path');

const UglifyJsPlugin = require('uglifyjs-webpack-plugin');

module.exports = {
    entry: './src/index.js',
    mode: 'production',
    output: {
        path: path.resolve(__dirname, './dist'),
        filename: 'threeds2-js-utils.js',
        library: 'ThreedDS2Utils',
        libraryTarget: 'umd',
        libraryExport: 'default',
        globalObject: 'this'
    },
    module: {
        rules: [{
            test: /\.js?$/,
            use: [
                {
                    loader: require.resolve('babel-loader'),
                    options: {
                        compact: true,
                        highlightCode: true
                    }
                }
            ]
        }]
    },
    optimization: {
        minimizer: [
            new UglifyJsPlugin({
                uglifyOptions: {
                    parse: {
                        // we want uglify-js to parse ecma 8 code. However, we don't want it
                        // to apply any minfication steps that turns valid ecma 5 code
                        // into invalid ecma 5 code. This is why the 'compress' and 'output'
                        // sections only apply transformations that are ecma 5 safe
                        // https://github.com/facebook/create-react-app/pull/4234
                        ecma: 8
                    },
                    compress: {
                        ecma: 5,
                        warnings: false,
                        // Disabled because of an issue with Uglify breaking seemingly valid code:
                        // https://github.com/facebook/create-react-app/issues/2376
                        // Pending further investigation:
                        // https://github.com/mishoo/UglifyJS2/issues/2011
                        comparisons: false
                    },
                    mangle: {
                        // Pass true to work around the Safari 10 loop
                        // iterator bug "Cannot declare a let variable twice".
                        safari10: true
                    },
                    output: {
                        ecma: 5,
                        comments: false,
                        // Turned on because emoji and regex is not minified properly using default
                        // https://github.com/facebook/create-react-app/issues/2488
                        ascii_only: true
                    }
                },
                // Use multi-process parallel running to improve the build speed
                // Default number of concurrent runs: os.cpus().length - 1
                parallel: true,
                // Enable file caching
                cache: true,
                sourceMap: false
            })
        ]
    }
};