stylus/rollup.config.mjs

import cjs from 'rollup-plugin-cjs-es';
import resolve from '@rollup/plugin-node-resolve';
import iife from 'rollup-plugin-iife';
import {terser} from 'rollup-plugin-terser';
import output from 'rollup-plugin-write-output';

import escapeRe from 'escape-string-regexp';

export default {
  input: {
    'codemirror/base': 'src/codemirror/base.mjs',
    'codemirror/edit': 'src/codemirror/edit.mjs',
  },
  output: {
    dir: 'dist',
    chunkFileNames: 'chunks/[name]-[hash].js',
  },
  plugins: [
    resolve(),
    cjs({nested: true}),
    iife(),
    terser({module: false}),
    output([
      {
        test: /codemirror\/edit\.js/,
        target: 'dist/edit.html',
        handle: (content, {htmlScripts}) => replaceLine(content, '<!-- codemirror-edit -->', htmlScripts),
      },
      {
        test: /codemirror\/base\.js/,
        target: 'dist/install-usercss/install-usercss.js',
        handle: (content, {scripts}) => replaceLine(content, '// codemirror-base',
          JSON.stringify(scripts.map(resolvePath('/install-usercss/install-usercss.js')))),
      },
    ]),
  ],
  preserveEntrySignatures: false,
};

function resolvePath(base) {
  return id => {
    const isAbs = base.startsWith('/');
    const u = new URL(id, `http://dummy${isAbs ? '' : '/'}${base}`);
    return isAbs ? u.pathname : u.pathname.slice(1);
  };
}

function replaceLine(content, marker, repl) {
  return content.replace(new RegExp(`\\S.*${escapeRe(marker)}`), `${repl} ${marker}`);
}