Function parsePackageName

lib/internal/modules/package_json_reader.js:233–265

* Parse a package name from a specifier. * @param {string} specifier - The import specifier. * @param {string | URL | undefined} base - The parent URL. * @returns {object}

(specifier, base)

 * @returns {object}
 */
function parsePackageName(specifier, base) {
  let separatorIndex = StringPrototypeIndexOf(specifier, '/');
  let validPackageName = true;
  let isScoped = false;
  if (specifier[0] === '@') {
    isScoped = true;
    if (separatorIndex === -1 || specifier.length === 0) {
      validPackageName = false;
    } else {
      separatorIndex = StringPrototypeIndexOf(
        specifier, '/', separatorIndex + 1);
    }
  }

  const packageName = separatorIndex === -1 ?
    specifier : StringPrototypeSlice(specifier, 0, separatorIndex);

  // Package name cannot have leading . and cannot have percent-encoding or
  // \\ separators.
  if (RegExpPrototypeExec(invalidPackageNameRegEx, packageName) !== null) {
    validPackageName = false;
  }

  if (!validPackageName) {
    throw new ERR_INVALID_MODULE_SPECIFIER(
      specifier, 'is not a valid package name', fileURLToPath(base));
  }

  const packageSubpath = '.' + (separatorIndex === -1 ? '' :
    StringPrototypeSlice(specifier, separatorIndex));

  return { packageName, packageSubpath, isScoped };
}

function getPackageJSONURL(specifier, base) {
  const { packageName, packageSubpath, isScoped } = parsePackageName(specifier, base);