No more CJS `$ node --experimental-loader ./no-cjs.mjs index.mjs`

index.mjs

import './no-more.cjs';

no-cjs.mjs

/**
 * @param {string} url
 * @param {Object} context (currently empty)
 * @param {Function} defaultGetFormat
 * @returns {Promise<{ format: string }>}
 */
export async function getFormat(url, context, defaultGetFormat) {
  const result = await defaultGetFormat(url);
  if (result.format === 'commonjs') {
    console.error(new Error(`${url} is a cjs module`));
    process.exit(1);
  }
  return result;
}

no-more.cjs

module.exports = 'this should not work';