Cache element indices for :nth-child and :nth-last-child selectors.

Source/core/dom/ContainerNode.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2013 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
  * version 2 of the License, or (at your option) any later version.
@@ skipping 16 matching lines @@
 #include "core/dom/ChildFrameDisconnector.h"
 #include "core/dom/ChildListMutationScope.h"
 #include "core/dom/ClassCollection.h"
 #include "core/dom/ElementTraversal.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/NameNodeList.h"
 #include "core/dom/NodeChildRemovalTracker.h"
 #include "core/dom/NodeLayoutStyle.h"
 #include "core/dom/NodeRareData.h"
 #include "core/dom/NodeTraversal.h"
+#include "core/dom/NthIndexCache.h"
 #include "core/dom/SelectorQuery.h"
 #include "core/dom/StaticNodeList.h"
 #include "core/dom/StyleEngine.h"
 #include "core/dom/shadow/ElementShadow.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/events/MutationEvent.h"
 #include "core/html/HTMLCollection.h"
 #include "core/html/HTMLFrameOwnerElement.h"
 #include "core/html/HTMLTagCollection.h"
 #include "core/html/RadioNodeList.h"
@@ skipping 801 matching lines @@
 void ContainerNode::childrenChanged(const ChildrenChange& change)
 {
     document().incDOMTreeVersion();
     if (!change.byParser && change.type != TextChanged)
         document().updateRangesAfterChildrenChanged(this);
     invalidateNodeListCachesInAncestors();
     if (change.isChildInsertion() && !childNeedsStyleRecalc()) {
         setChildNeedsStyleRecalc();
         markAncestorsWithChildNeedsStyleRecalc();
     }
+    ASSERT(!document().nthIndexCache());
 }
 
 void ContainerNode::cloneChildNodes(ContainerNode *clone)
 {
     TrackExceptionState exceptionState;
     for (Node* n = firstChild(); n && !exceptionState.hadException(); n = n->nextSibling())
         clone->appendChild(n->cloneNode(true), exceptionState);
 }
 
 
@@ skipping 283 matching lines @@
 PassRefPtrWillBeRawPtr<Element> ContainerNode::querySelector(const AtomicString& selectors, ExceptionState& exceptionState)
 {
     if (selectors.isEmpty()) {
         exceptionState.throwDOMException(SyntaxError, "The provided selector is empty.");
         return nullptr;
     }
 
     SelectorQuery* selectorQuery = document().selectorQueryCache().add(selectors, document(), exceptionState);
     if (!selectorQuery)
         return nullptr;
+
+    Document::UseNthIndexCacheScope nthIndexScope(document());
     return selectorQuery->queryFirst(*this);
 }
 
 PassRefPtrWillBeRawPtr<StaticElementList> ContainerNode::querySelectorAll(const AtomicString& selectors, ExceptionState& exceptionState)
 {
     if (selectors.isEmpty()) {
         exceptionState.throwDOMException(SyntaxError, "The provided selector is empty.");
         return nullptr;
     }
 
     SelectorQuery* selectorQuery = document().selectorQueryCache().add(selectors, document(), exceptionState);
     if (!selectorQuery)
         return nullptr;
 
+    Document::UseNthIndexCacheScope nthIndexScope(document());
     return selectorQuery->queryAll(*this);
 }
 
 static void dispatchChildInsertionEvents(Node& child)
 {
     if (child.isInShadowTree())
         return;
 
     ASSERT(!EventDispatchForbiddenScope::isEventDispatchForbidden());
 
@@ skipping 300 matching lines @@
         return true;
 
     if (node->isElementNode() && toElement(node)->shadow())
         return true;
 
     return false;
 }
 #endif
 
 } // namespace blink