Function createModuleLoader

lib/internal/modules/esm/loader.js:869–900

* A loader instance is used as the main entry point for loading ES modules. Currently, this is a singleton; there is * only one used for loading the main module and everything in its dependency graph, though separate instances of this * class might be instantiated as part of bootstrap for other pu

(asyncLoaderHooks)

 * @returns {ModuleLoader}
 */
function createModuleLoader(asyncLoaderHooks) {
  // Don't spawn a new loader hook worker if we are already in a loader hook worker to avoid infinite recursion.
  if (shouldSpawnLoaderHookWorker()) {
    assert(asyncLoaderHooks === undefined, 'asyncLoaderHooks should only be provided on the loader hook thread itself');
    const userLoaderPaths = getOptionValue('--experimental-loader');
    if (userLoaderPaths.length > 0) {
      if (!emittedLoaderFlagWarning) {
        const readableURIEncode = (string) => ArrayPrototypeReduce(
          [
            [/'/g, '%27'], // We need to URL-encode the single quote as it's the delimiter for the --import flag.
            [/%22/g, '"'], // We can decode the double quotes to improve readability.
            [/%2F/ig, '/'], // We can decode the slashes to improve readability.
          ],
          (str, { 0: regex, 1: replacement }) => RegExpPrototypeSymbolReplace(hardenRegExp(regex), str, replacement),
          encodeURIComponent(string));
        process.emitWarning(
          '`--experimental-loader` may be removed in the future; instead use `register()`:\n' +
          `--import 'data:text/javascript,import { register } from "node:module"; import { pathToFileURL } from "node:url"; ${ArrayPrototypeJoin(
            ArrayPrototypeMap(userLoaderPaths, (loader) => `register(${readableURIEncode(JSONStringify(loader))}, pathToFileURL("./"))`),
            '; ',
          )};'`,
          'ExperimentalWarning',
        );
        emittedLoaderFlagWarning = true;
      }
      const { AsyncLoaderHooksProxiedToLoaderHookWorker } = require('internal/modules/esm/hooks');
      asyncLoaderHooks = new AsyncLoaderHooksProxiedToLoaderHookWorker();
    }
  }

  return new ModuleLoader(asyncLoaderHooks);
}

let allowImportMetaResolveParentURL;
/**