rollup.config.mjs

import babel from '@rollup/plugin-babel';
// import terser from '@rollup/plugin-terser';
// import pkg from './package.json' assert {type: "json"};
import { createRequire } from 'node:module';

const require = createRequire(import.meta.url);
const terser = require('@rollup/plugin-terser');
const pkg = require('./package.json');

const banner = `
/*!
  * ${pkg.name} v${pkg.version} (${pkg.homepage})
  * Copyright (c) 2019-present ${pkg.author}
  * Licensed under ${pkg.license} (${pkg.homepage}/blob/master/LICENSE)
  */
`;

export default {
  input: 'src/index.js',
  plugins: [
    babel({
      exclude: ['node_modules/**']
    })
  ],
  output: [
    // browser-friendly UMD build
    {
      name: pkg.name,
      file: pkg.unpkg.replace('.min.', '.'),
      sourcemap: true,
      format: 'umd'
    },
    {
      name: pkg.name,
      banner,
      file: pkg.unpkg,
      sourcemap: true,
      format: 'umd',
      plugins: [terser({output: {comments: /^!/}})]
    },
    // 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)
    {
      file: pkg.main,
      sourcemap: true,
      format: 'cjs'
    },
    {
      file: pkg.module,
      sourcemap: true,
      format: 'es'
    }
  ]
};