Count consecutive direct adjacent selectors.

Source/core/css/RuleFeature.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
@@ skipping 153 matching lines @@
     return *addResult.iterator->value;
 }
 
 void RuleFeatureSet::collectFeaturesFromSelector(const CSSSelector& selector)
 {
     collectFeaturesFromSelector(selector, m_metadata);
 }
 
 void RuleFeatureSet::collectFeaturesFromSelector(const CSSSelector& selector, RuleFeatureSet::FeatureMetadata& metadata)
 {
+    unsigned maxDirectAdjacentSelectors = 0;
+
     for (const CSSSelector* current = &selector; current; current = current->tagHistory()) {
         if (current->m_match == CSSSelector::Id)
             metadata.idsInRules.add(current->value());
         else if (current->m_match == CSSSelector::Class)
             metadata.classesInRules.add(current->value());
         else if (current->isAttributeSelector())
             metadata.attrsInRules.add(current->attribute().localName());
 
         if (current->pseudoType() == CSSSelector::PseudoFirstLine)
             metadata.usesFirstLineRules = true;
-        if (current->isDirectAdjacentSelector())
-            metadata.maxDirectAdjacentSelectors++;
+        if (current->isDirectAdjacentSelector()) {
+            maxDirectAdjacentSelectors++;
+        } else if (maxDirectAdjacentSelectors) {
+            if (maxDirectAdjacentSelectors > metadata.maxDirectAdjacentSelectors)
+                metadata.maxDirectAdjacentSelectors = maxDirectAdjacentSelectors;
+            maxDirectAdjacentSelectors = 0;
+        }
         if (current->isSiblingSelector())
             metadata.foundSiblingSelector = true;
 
         collectFeaturesFromSelectorList(current->selectorList(), metadata);
     }
+
+    ASSERT(!maxDirectAdjacentSelectors);
 }
 
 void RuleFeatureSet::collectFeaturesFromSelectorList(const CSSSelectorList* selectorList, RuleFeatureSet::FeatureMetadata& metadata)
 {
     if (!selectorList)
         return;
 
     for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(*selector)) {
         for (const CSSSelector* subSelector = selector; subSelector; subSelector = subSelector->tagHistory())
             collectFeaturesFromSelector(*subSelector, metadata);
@@ skipping 203 matching lines @@
 
     if (thisElementNeedsStyleRecalc)
         element->setNeedsStyleRecalc(LocalStyleChange);
 
     invalidationClasses.remove(oldSize, invalidationClasses.size() - oldSize);
     element->clearChildNeedsStyleInvalidation();
     return thisElementNeedsStyleRecalc;
 }
 
 } // namespace WebCore