rollup.config.js

import resolve from 'rollup-plugin-node-resolve';
import commonjs from 'rollup-plugin-commonjs';
import { terser } from "rollup-plugin-terser";
import babel from 'rollup-plugin-babel';

let plugins = [
    babel({
        exclude: 'node_modules/**',
    }),
    resolve({
        // use "module" field for ES6 module if possible
        module: true, // Default: true

        // use "jsnext:main" if possible
        // – see https://github.com/rollup/rollup/wiki/jsnext:main
        jsnext: false,  // Default: false

        // use "main" field or index.js, even if it's not an ES6 module
        // (needs to be converted from CommonJS to ES6
        // – see https://github.com/rollup/rollup-plugin-commonjs
        main: true,  // Default: true

        // some package.json files have a `browser` field which
        // specifies alternative files to load for people bundling
        // for the browser. If that's you, use this option, otherwise
        // pkg.browser will be ignored
        browser: true,  // Default: false

        // not all files you want to resolve are .js files
        extensions: [ '.mjs', '.js', '.jsx', '.json' ],  // Default: [ '.mjs', '.js', '.json', '.node' ]

        // whether to prefer built-in modules (e.g. `fs`, `path`) or
        // local ones with the same names
        preferBuiltins: false,  // Default: true

        // Lock the module search in this path (like a chroot). Module defined
        // outside this path will be marked as external
        // jail: '/my/jail/path', // Default: '/'

        // Set to an array of strings and/or regexps to lock the module search
        // to modules that match at least one entry. Modules not matching any
        // entry will be marked as external
        only: [
            /^fp-rosetree$/,
            /^json-patch-es6/,
            /^graph-adt/,
        ], // Default: null

        // If true, inspect resolved files to check that they are
        // ES2015 modules
        modulesOnly: false, // Default: false

        // Any additional options that should be passed through
        // to node-resolve
        // customResolveOptions: {
        //   moduleDirectory: 'mode_modules'
        // }
    }),
    commonjs({
        include: ['node_modules/**', "node_modules/deep-equal/**"],
        //   // non-CommonJS modules will be ignored, but you can also
        //   // specifically include/exclude files
        //   include: 'node_modules/fast-json-patch/lib/duplex.js',  // Default: undefined
        //   // exclude: [ 'node_modules/foo/**', 'node_modules/bar/**' ],  // Default: undefined
        //   // these values can also be regular expressions
        //   // include: /node_modules/
        //   // exclude: [ /node_modules\/[a-f].*/], mined
        //
        //   // search for files other than .js files (must already
        //   // be transpiled by a previous plugin!)
        //   // extensions: [ '.js', '.coffee' ],  // Default: [ '.js' ]
        //
        //   // if true then uses of `global` won't be dealt with by this plugin
        //   ignoreGlobal: false,  // Default: false
        //
        //   // if false then skip sourceMap generation for CommonJS modules
        //   // sourceMap: false,  // Default: true
        //
        //   // explicitly specify unresolvable named exports
        //   // (see below for more details)
        //   namedExports: { './module.js': ['foo', 'bar' ] },  // Default: undefined
        //
        //   // sometimes you have to leave require statements
        //   // unconverted. Pass an array containing the IDs
        //   // or a `id => boolean` function. Only use this
        //   // option if you know what you're doing!
        //   ignore: [ 'conditional-runtime-dependency' ]
    }),
];
let suffix="";

if (process.env.BUILD == "production") {
  plugins = plugins.concat(terser())
    suffix = ".min";
}

const exp = {
    input: 'src/index.js',
    output: [{
        file: `dist/kingly.umd${suffix}.js`,
        format: 'umd',
        name: 'Kingly',
    },{
        file: `dist/kingly.es${suffix}.js`,
        format: 'esm',
        name: 'Kingly',
    },
    ],
    plugins
};

export default exp