Make NodeIterator.detach() a no-op

Source/core/dom/NodeIterator.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2000 Frederik Holljen (frederik.holljen@hig.no)
  * Copyright (C) 2001 Peter Kelly (pmk@post.com)
  * Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2004, 2008 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 11 matching lines @@
  *
  */
 
 #include "config.h"
 #include "core/dom/NodeIterator.h"
 
 #include "bindings/v8/ExceptionState.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/NodeTraversal.h"
+#include "core/frame/UseCounter.h"
 
 namespace WebCore {
 
 NodeIterator::NodePointer::NodePointer()
 {
 }
 
 NodeIterator::NodePointer::NodePointer(PassRefPtr<Node> n, bool b)
     : node(n)
     , isPointerBeforeNode(b)
@@ skipping 25 matching lines @@
         isPointerBeforeNode = true;
         return true;
     }
     node = NodeTraversal::previous(*node, root);
     return node;
 }
 
 NodeIterator::NodeIterator(PassRefPtr<Node> rootNode, unsigned whatToShow, PassRefPtr<NodeFilter> filter)
     : NodeIteratorBase(rootNode, whatToShow, filter)
     , m_referenceNode(root(), true)
-    , m_detached(false)
 {
     ScriptWrappable::init(this);
     root()->document().attachNodeIterator(this);
 }
 
 NodeIterator::~NodeIterator()
 {
     root()->document().detachNodeIterator(this);
 }
 
 PassRefPtr<Node> NodeIterator::nextNode(ExceptionState& exceptionState)
 {
-    if (m_detached) {
-        exceptionState.throwDOMException(InvalidStateError, "The iterator is detached.");
-        return nullptr;
-    }
-
     RefPtr<Node> result;
 
     m_candidateNode = m_referenceNode;
     while (m_candidateNode.moveToNext(root())) {
         // NodeIterators treat the DOM tree as a flat list of nodes.
         // In other words, FILTER_REJECT does not pass over descendants
         // of the rejected node. Hence, FILTER_REJECT is the same as FILTER_SKIP.
         RefPtr<Node> provisionalResult = m_candidateNode.node;
         bool nodeWasAccepted = acceptNode(provisionalResult.get(), exceptionState) == NodeFilter::FILTER_ACCEPT;
         if (exceptionState.hadException())
             break;
         if (nodeWasAccepted) {
             m_referenceNode = m_candidateNode;
             result = provisionalResult.release();
             break;
         }
     }
 
     m_candidateNode.clear();
     return result.release();
 }
 
 PassRefPtr<Node> NodeIterator::previousNode(ExceptionState& exceptionState)
 {
-    if (m_detached) {
-        exceptionState.throwDOMException(InvalidStateError, "The iterator is detached.");
-        return nullptr;
-    }
-
     RefPtr<Node> result;
 
     m_candidateNode = m_referenceNode;
     while (m_candidateNode.moveToPrevious(root())) {
         // NodeIterators treat the DOM tree as a flat list of nodes.
         // In other words, FILTER_REJECT does not pass over descendants
         // of the rejected node. Hence, FILTER_REJECT is the same as FILTER_SKIP.
         RefPtr<Node> provisionalResult = m_candidateNode.node;
         bool nodeWasAccepted = acceptNode(provisionalResult.get(), exceptionState) == NodeFilter::FILTER_ACCEPT;
         if (exceptionState.hadException())
             break;
         if (nodeWasAccepted) {
             m_referenceNode = m_candidateNode;
             result = provisionalResult.release();
             break;
         }
     }
 
     m_candidateNode.clear();
     return result.release();
 }
 
 void NodeIterator::detach()
 {
-    root()->document().detachNodeIterator(this);
-    m_detached = true;
-    m_referenceNode.node.clear();
+    // This is now a no-op as per the DOM specification.
 }
 
 void NodeIterator::nodeWillBeRemoved(Node& removedNode)
 {
     updateForNodeRemoval(removedNode, m_candidateNode);
     updateForNodeRemoval(removedNode, m_referenceNode);
 }
 
 void NodeIterator::updateForNodeRemoval(Node& removedNode, NodePointer& referenceNode) const
 {
-    ASSERT(!m_detached);
     ASSERT(root()->document() == removedNode.document());
 
     // Iterator is not affected if the removed node is the reference node and is the root.
     // or if removed node is not the reference node, or the ancestor of the reference node.
     if (!removedNode.isDescendantOf(root()))
         return;
     bool willRemoveReferenceNode = removedNode == referenceNode.node;
     bool willRemoveReferenceNodeAncestor = referenceNode.node && referenceNode.node->isDescendantOf(&removedNode);
     if (!willRemoveReferenceNode && !willRemoveReferenceNodeAncestor)
         return;
@@ skipping 46 matching lines @@
                     node = NodeTraversal::previous(*node, root());
             }
             if (node)
                 referenceNode.node = node;
         }
     }
 }
 
 
 } // namespace WebCore