rollup.config.js

import buble from '@rollup/plugin-buble';
import copy from 'rollup-plugin-copy'

let copyVim = copy({
  targets: [
    { 
      src: require.resolve("cm5-vim/vim.js").replace(/\\/g,  "/"), 
      dest: "./keymap" 
    }
  ]
});

export default [
  {
    input: "src/codemirror.js",
    output: {
      banner: `// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: https://codemirror.net/5/LICENSE

// This is CodeMirror (https://codemirror.net/5), a code editor
// implemented in JavaScript on top of the browser's DOM.
//
// You can find some technical background for some of the code below
// at http://marijnhaverbeke.nl/blog/#cm-internals .
`,
      format: "umd",
      file: "lib/codemirror.js",
      name: "CodeMirror"
    },
    plugins: [ buble({namedFunctionExpressions: false}), copyVim ]
  },
  {
    input: ["src/addon/runmode/runmode-standalone.js"],
    output: {
      format: "iife",
      file: "addon/runmode/runmode-standalone.js",
      name: "CodeMirror",
      freeze: false, // IE8 doesn't support Object.freeze.
    },
    plugins: [ buble({namedFunctionExpressions: false}) ]
  },
  {
    input: ["src/addon/runmode/runmode.node.js"],
    output: {
      format: "cjs",
      file: "addon/runmode/runmode.node.js",
      name: "CodeMirror",
      freeze: false, // IE8 doesn't support Object.freeze.
    },
    plugins: [ buble({namedFunctionExpressions: false}) ]
  },
];