1// Copyright (c) 2013 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5function isOptionElementToggleable(option) { 6 if (option.tagName.toLowerCase() != 'option') 7 throw new Error('element is not an option'); 8 for (var parent = option.parentElement; 9 parent; 10 parent = parent.parentElement) { 11 if (parent.tagName.toLowerCase() == 'select') { 12 return parent.multiple; 13 } 14 } 15 throw new Error('option element is not in a select'); 16} 17