code: function isEmptyObject(obj) {
    if (isEmpty(obj) === true) {
      return true;
    }
    if (Object.getOwnPropertyNames(obj).length === 0) {
      //if (Object.keys(obj).length === 0 && Object.getOwnPropertyNames(obj).length === 0) {
      return true;
    }
    return false;
  }
docs: enumerable を含めるかどうかで分けないといけないかも