rollup.config.js

// https://github.com/rollup/rollup-starter-lib/blob/master/rollup.config.js
import pkg from './package.json';
import babel from "rollup-plugin-babel";

export default [
    // browser-friendly UMD build
    {
        input: 'src/EventEmitter.js',
        output: {
            file: pkg.browser,
            format: 'umd'
        },
        name: 'EventEmitter',
        plugins: [
            babel({
                exclude: "node_modules/**"
            })
        ],
        noConflict : true
    },
    // CommonJS (for Node) and ES module (for bundlers) build.
    // (We could have three entries in the configuration array
    // instead of two, but it's quicker to generate multiple
    // builds from a single configuration where possible, using
    // an array for the `output` option, where we can specify
    // `file` and `format` for each target)
    {
        input: 'src/EventEmitter.js',
        output: [

            { file: pkg.main, format: 'cjs' },
            { file: pkg.module, format: 'es' }
        ],
        plugins: [
            babel({
                exclude: "node_modules/**"
            })
        ]
    }
];