Adding ChromeVox as a component extensions (enabled only for ChromeOS, for no...

chrome/browser/resources/access_chromevox/common/xpath_util.js

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/**
+ * @fileoverview A collection of JavaScript utilities used to simplify working
+ * with xpaths.
+ */
+
+
+goog.provide('cvox.XpathUtil');
+
+
+/**
+ * Utilities for simplifying working with xpaths
+ * @constructor
+ */
+cvox.XpathUtil = function() {
+ };
+
+
+/**
+ * Given an XPath expression and rootNode, it returns an array of children nodes
+ * that match. The code for this function was taken from Mihai Parparita's GMail
+ * Macros Greasemonkey Script.
+ * http://gmail-greasemonkey.googlecode.com/svn/trunk/scripts/gmail-new-macros.user.js
+ * @param {string} expression The XPath expression to evaluate.
+ * @param {Node} rootNode The HTML node to start evaluating the XPath from.
+ * @return {Array} The array of children nodes that match.
+ */
+cvox.XpathUtil.evalXPath = function(expression, rootNode) {
+  try {
+    var xpathIterator = rootNode.ownerDocument.evaluate(
+      expression,
+      rootNode,
+      null, // no namespace resolver
+      XPathResult.ORDERED_NODE_ITERATOR_TYPE,
+      null); // no existing results
+  } catch (err) {
+    return [];
+  }
+  var results = [];
+  // Convert result to JS array
+  for (var xpathNode = xpathIterator.iterateNext();
+       xpathNode;
+       xpathNode = xpathIterator.iterateNext()) {
+    results.push(xpathNode);
+  }
+  return results;
+};
+
+/**
+ * Given a rootNode, it returns an array of all its leaf nodes.
+ * @param {Node} rootNode The node to get the leaf nodes from.
+ * @return {Array} The array of leaf nodes for the given rootNode.
+ */
+cvox.XpathUtil.getLeafNodes = function(rootNode) {
+  try {
+    var xpathIterator = rootNode.ownerDocument.evaluate(
+      './/*[count(*)=0]',
+      rootNode,
+      null, // no namespace resolver
+      XPathResult.ORDERED_NODE_ITERATOR_TYPE,
+      null); // no existing results
+  } catch (err) {
+    return [];
+  }
+  var results = [];
+  // Convert result to JS array
+  for (var xpathNode = xpathIterator.iterateNext();
+       xpathNode;
+       xpathNode = xpathIterator.iterateNext()) {
+    results.push(xpathNode);
+  }
+  return results;
+};
+