import uglify from 'rollup-plugin-uglify'; const umdConfig = { output: { format: 'umd', name: 'Promise', }, plugins: [] }; if (process.env.NODE_ENV === 'production') { umdConfig.plugins.push( uglify({ compress: { pure_getters: true, unsafe: true, unsafe_comps: true, warnings: false, ie8: true }, mangle: { ie8: true }, output: { ie8: true } }) ); } export default umdConfig;