Make character text changes work in Docs

chrome/browser/resources/chromeos/chromevox/cvox2/background/cursors.js

 // Copyright 2014 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 Classes related to cursors that point to and select parts of
  * the automation tree.
  */
 
 goog.provide('cursors.Cursor');
 goog.provide('cursors.Movement');
 goog.provide('cursors.Range');
 goog.provide('cursors.Unit');
 
+goog.require('AncestryRecoveryStrategy');
 goog.require('AutomationPredicate');
 goog.require('AutomationUtil');
+goog.require('RecoveryStrategy');
 goog.require('StringUtil');
 goog.require('constants');
 
 /**
  * The special index that represents a cursor pointing to a node without
  * pointing to any part of its accessible text.
  */
 cursors.NODE_INDEX = -1;
 
 /**
@@ skipping 50 matching lines @@
 cursors.Cursor = function(node, index) {
   // Compensate for specific issues in Blink.
   // TODO(dtseng): Pass through affinity; if upstream, skip below.
   if (node.role == RoleType.STATIC_TEXT && node.name.length == index) {
     // Re-interpret this case as the beginning of the next node.
     var nextNode = AutomationUtil.findNextNode(
         node, Dir.FORWARD, AutomationPredicate.leafOrStaticText);
 
     // The exception is when a user types at the end of a line. In that case,
     // staying on the current node is appropriate.
-    if (node && node.nextOnLine && nextNode) {
+    if (node && node.nextOnLine && node.nextOnLine.role && nextNode) {
       node = nextNode;
       index = 0;
     }
   } else if (
       node.role == RoleType.GENERIC_CONTAINER && node.state.richlyEditable &&
       (node.firstChild &&
        (node.firstChild.role == RoleType.LINE_BREAK ||
         node.firstChild.role == RoleType.STATIC_TEXT))) {
     // Re-interpret this case as pointing to the text under the div.
     node = node.find({role: RoleType.INLINE_TEXT_BOX}) || node;
   }
 
   /** @type {number} @private */
   this.index_ = index;
-  /** @type {Array<AutomationNode>} @private */
-  this.ancestry_ = [];
-  var nodeWalker = node;
-  while (nodeWalker) {
-    this.ancestry_.push(nodeWalker);
-    nodeWalker = nodeWalker.parent;
-    if (nodeWalker && nodeWalker.role == RoleType.WINDOW)
-      break;
-  }
+  /** @type {RecoveryStrategy} */
+  this.recovery_ = new AncestryRecoveryStrategy(node);
 };
 
 /**
  * Convenience method to construct a Cursor from a node.
  * @param {!AutomationNode} node
  * @return {!cursors.Cursor}
  */
 cursors.Cursor.fromNode = function(node) {
   return new cursors.Cursor(node, cursors.NODE_INDEX);
 };
@@ skipping 49 matching lines @@
       return rhs.index < this.index ? Dir.BACKWARD : Dir.FORWARD;
     return AutomationUtil.getDirection(this.node, rhs.node);
   },
 
   /**
    * Returns the node. If the node is invalid since the last time it
    * was accessed, moves the cursor to the nearest valid ancestor first.
    * @return {AutomationNode}
    */
   get node() {
-    for (var i = 0; i < this.ancestry_.length; i++) {
-      var firstValidNode = this.ancestry_[i];
-      if (firstValidNode != null && firstValidNode.role !== undefined &&
-          firstValidNode.root != undefined) {
-        return firstValidNode;
-      }
-      // If we have to walk up to an ancestor, reset the index to NODE_INDEX.
+    if (this.recovery_.requiresRecovery()) {
+      // If we need to recover, the index is no longer valid.
       this.index_ = cursors.NODE_INDEX;
     }
-    return null;
+    return this.recovery_.node;
   },
 
   /**
    * @return {number}
    */
   get index() {
     return this.index_;
   },
 
 
@@ skipping 567 matching lines @@
   /**
    * Returns whether this range has valid start and end cursors.
    * @return {boolean}
    */
   isValid: function() {
     return this.start.isValid() && this.end.isValid();
   }
 };
 
 });  // goog.scope