LitElement ESM build 2/2 - lit-element bundle

rollup.config.js

import resolve from 'rollup-plugin-node-resolve';
import commonjs from 'rollup-plugin-commonjs';

export default [
  // esm + es2017 w/o lit-element
  {//...},
  
  // lit-element bundle
  {
    input: 'node_modules/lit-element/lit-element.js',
    output: {
      file: `lib/lit-element.js`,
      format: 'es'
    },
    plugins: [resolve(), commonjs()]
  }
];