Rich editable text implementation using spannables

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');
@@ skipping 57 matching lines @@
 
 /**
  * Represents a position within the automation tree.
  * @constructor
  * @param {!AutomationNode} node
  * @param {number} index A 0-based index into this cursor node's primary
  * accessible name. An index of |cursors.NODE_INDEX| means the node as a whole
  * is pointed to and covers the case where the accessible text is empty.
  */
 cursors.Cursor = function(node, index) {
+  // Compensate for specific issues in Blink.
+  if (node.role == RoleType.STATIC_TEXT && node.name.length == index) {
+    // Re-interpret this case as the beginning of the next node.

[dmazzoni, 2017/06/07 17:30:13]

Add a TODO to take affinity as an argument to Cursor and to
check affinity. If affinity is downstream, which is the most
common, this is correct - but if it's upstream, we should leave
the cursor at the end of that 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 (nextNode && nextNode.nextOnLine) {
+      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;
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   /**
    * Returns whether this range has valid start and end cursors.
    * @return {boolean}
    */
   isValid: function() {
     return this.start.isValid() && this.end.isValid();
   }
 };
 
 });  // goog.scope