Function executeUserEntryPoint

lib/internal/modules/run_main.js:140–165

* Parse the CLI main entry point string and run it. * For backwards compatibility, we have to run a bunch of monkey-patchable code that belongs to the CJS loader (exposed * by `require('module')`) even when the entry point is ESM. * Because of backwards compatibility, this function is exposed pub

(main = process.argv[1])

 * @param {string} main - First positional CLI argument, such as `'entry.js'` from `node entry.js`
 */
function executeUserEntryPoint(main = process.argv[1]) {
  let useESMLoader;
  let resolvedMain;
  if (getOptionValue('--entry-url')) {
    useESMLoader = true;
  } else {
    resolvedMain = resolveMainPath(main);
    useESMLoader = shouldUseESMLoader(resolvedMain);
  }
  // Unless we know we should use the ESM loader to handle the entry point per the checks in `shouldUseESMLoader`, first
  // try to run the entry point via the CommonJS loader; and if that fails under certain conditions, retry as ESM.
  if (!useESMLoader) {
    const cjsLoader = require('internal/modules/cjs/loader');
    const { wrapModuleLoad } = cjsLoader;
    wrapModuleLoad(main, null, true);
  } else {
    const mainPath = resolvedMain || main;
    const mainURL = getOptionValue('--entry-url') ? new URL(mainPath, getCWDURL()) : pathToFileURL(mainPath);

    runEntryPointWithESMLoader((cascadedLoader) => {
      // Note that if the graph contains unsettled TLA, this may never resolve
      // even after the event loop stops running.
      return cascadedLoader.import(mainURL, undefined, { __proto__: null }, undefined, true);
    });
  }
}

module.exports = {
  executeUserEntryPoint,