Implement the inert attribute

third_party/WebKit/Source/modules/accessibility/AXObject.cpp

 /*
  * Copyright (C) 2008, 2009, 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 518 matching lines @@
   if (getNode()) {
     if (getNode()->isInert()) {
       if (ignoredReasons) {
         HTMLDialogElement* dialog = getActiveDialogElement(getNode());
         if (dialog) {
           AXObject* dialogObject = axObjectCache().getOrCreate(dialog);
           if (dialogObject)
             ignoredReasons->push_back(
                 IgnoredReason(AXActiveModalDialog, dialogObject));
           else
-            ignoredReasons->push_back(IgnoredReason(AXInert));
+            ignoredReasons->push_back(IgnoredReason(AXInertElement));
         } else {
-          // TODO(aboxhall): handle inert attribute if it eventuates
-          ignoredReasons->push_back(IgnoredReason(AXInert));
+          const AXObject* inertRoot = this->inertRoot();
+          if (inertRoot == this) {
+            ignoredReasons->push_back(IgnoredReason(AXInertElement));
+          } else {
+            ignoredReasons->push_back(IgnoredReason(AXInertSubtree, inertRoot));
+          }
         }
       }
       return true;
     }
   } else {
     AXObject* parent = parentObject();
     if (parent && parent->isInertOrAriaHidden()) {
       if (ignoredReasons)
         parent->computeIsInertOrAriaHidden(ignoredReasons);
       return true;
     }
   }
 
   const AXObject* hiddenRoot = ariaHiddenRoot();
   if (hiddenRoot) {
     if (ignoredReasons) {
-      if (hiddenRoot == this)
-        ignoredReasons->push_back(IgnoredReason(AXAriaHidden));
-      else
-        ignoredReasons->push_back(IgnoredReason(AXAriaHiddenRoot, hiddenRoot));
+      if (hiddenRoot == this) {
+        ignoredReasons->push_back(IgnoredReason(AXAriaHiddenElement));
+      } else {
+        ignoredReasons->push_back(
+            IgnoredReason(AXAriaHiddenSubtree, hiddenRoot));
+      }
     }
     return true;
   }
 
   return false;
 }
 
 bool AXObject::isDescendantOfLeafNode() const {
   updateCachedAttributeValuesIfNeeded();
   return m_cachedIsDescendantOfLeafNode;
@@ skipping 12 matching lines @@
 
 const AXObject* AXObject::ariaHiddenRoot() const {
   for (const AXObject* object = this; object; object = object->parentObject()) {
     if (equalIgnoringCase(object->getAttribute(aria_hiddenAttr), "true"))
       return object;
   }
 
   return 0;
 }
 
+const AXObject* AXObject::inertRoot() const {
+  const AXObject* object = this;
+  if (!RuntimeEnabledFeatures::inertAttributeEnabled())
+    return nullptr;
+
+  while (object && !object->isAXNodeObject())
+    object = object->parentObject();
+  Node* node = object->getNode();
+  node->updateDistribution();

[esprehn, 2017/02/16 06:28:12]

updateDistribution can actually cause a detach(), which can then destroy and
recrete the AXObject tree, I think you want to call this higher up in the
system?

Actually since this is inside the AXObject tree, and that depends on style, this
should only be used after we called updateStyle() which updates distribution, so
can distribution be dirty here?

+  Element* element = node->isElementNode()
+                         ? toElement(node)
+                         : FlatTreeTraversal::parentElement(*node);
+  while (element) {
+    if (element->hasAttribute(inertAttr))
+      return axObjectCache().getOrCreate(element);
+    element = FlatTreeTraversal::parentElement(*element);
+  }
+
+  return nullptr;
+}
+
 bool AXObject::isDescendantOfDisabledNode() const {
   updateCachedAttributeValuesIfNeeded();
   return m_cachedIsDescendantOfDisabledNode;
 }
 
 const AXObject* AXObject::disabledAncestor() const {
   const AtomicString& disabled = getAttribute(aria_disabledAttr);
   if (equalIgnoringCase(disabled, "true"))
     return this;
   if (equalIgnoringCase(disabled, "false"))
@@ skipping 1157 matching lines @@
 }
 
 DEFINE_TRACE(AXObject) {
   visitor->trace(m_children);
   visitor->trace(m_parent);
   visitor->trace(m_cachedLiveRegionRoot);
   visitor->trace(m_axObjectCache);
 }
 
 }  // namespace blink