Support invalidation sets for :host pseudo.

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 29 matching lines @@
 
 namespace WebCore {
 
 static bool isSkippableComponentForInvalidation(const CSSSelector& selector)
 {
     if (selector.m_match == CSSSelector::Tag
         || selector.m_match == CSSSelector::Id
         || selector.isAttributeSelector())
         return true;
     if (selector.m_match == CSSSelector::PseudoElement) {
-        switch (selector.m_pseudoType) {
+        switch (selector.pseudoType()) {
         case CSSSelector::PseudoBefore:
         case CSSSelector::PseudoAfter:
         case CSSSelector::PseudoBackdrop:
             return true;
         default:
             return false;
         }
     }
     if (selector.m_match != CSSSelector::PseudoClass)
         return false;
@@ skipping 44 matching lines @@
 RuleFeatureSet::InvalidationSetMode RuleFeatureSet::supportsClassDescendantInvalidation(const CSSSelector& selector)
 {
     bool foundDescendantRelation = false;
     bool foundIdent = false;
     for (const CSSSelector* component = &selector; component; component = component->tagHistory()) {
 
         // FIXME: next up: Tag and Id.
         if (component->m_match == CSSSelector::Class || component->isAttributeSelector()) {
             if (!foundDescendantRelation)
                 foundIdent = true;
+        } else if (component->pseudoType() == CSSSelector::PseudoHost) {
+            if (const CSSSelectorList* selectorList = component->selectorList()) {
+                for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(*selector)) {
+                    InvalidationSetMode hostMode = supportsClassDescendantInvalidation(*selector);
+                    if (hostMode == UseSubtreeStyleChange)
+                        return foundDescendantRelation ? UseLocalStyleChange : UseSubtreeStyleChange;
+                    if (hostMode == AddFeatures)
+                        foundIdent = true;
+                }
+            }
         } else if (!isSkippableComponentForInvalidation(*component)) {
             return foundDescendantRelation ? UseLocalStyleChange : UseSubtreeStyleChange;
         }
         switch (component->relation()) {
         case CSSSelector::Descendant:
         case CSSSelector::Child:
         case CSSSelector::Shadow:
         case CSSSelector::ShadowDeep:
             foundDescendantRelation = true;
             // Fall through!
@@ skipping 36 matching lines @@
 {
     InvalidationSetMode mode = supportsClassDescendantInvalidation(selector);
     if (mode != AddFeatures)
         return mode;
 
     Vector<AtomicString> classes;
     AtomicString id;
     AtomicString tagName;
     Vector<AtomicString> attributes;
 
+    const CSSSelector* current = extractInvalidationSetFeatures(selector, classes, id, tagName, attributes);
+    if (current)
+        current = current->tagHistory();
+
+    if (!current)
+        return AddFeatures;
+
+    addFeaturesToInvalidationSets(*current, classes, id, tagName, attributes);
+    return AddFeatures;

[esprehn, 2014/03/24 16:09:11]

Since you're always going to return AddFeatures this should be

if (current)
  addFeaturesToInvalidationSets(*current, classes, id, tagName, attributes);
return AddFeatures;

[rune, 2014/03/24 17:17:18]

Done.

+}
+
+const CSSSelector* RuleFeatureSet::extractInvalidationSetFeatures(const CSSSelector& selector, Vector<AtomicString>& classes, AtomicString& id, AtomicString& tagName, Vector<AtomicString>& attributes)
+{
     const CSSSelector* lastSelector = &selector;
     for (; lastSelector; lastSelector = lastSelector->tagHistory()) {
         extractClassIdTagOrAttribute(*lastSelector, classes, id, tagName, attributes);
         // Initialize the entry in the invalidation set map, if supported.
         invalidationSetForSelector(*lastSelector);
+        if (lastSelector->pseudoType() == CSSSelector::PseudoHost) {
+            if (const CSSSelectorList* selectorList = lastSelector->selectorList()) {
+                for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(*selector))
+                    extractInvalidationSetFeatures(*selector, classes, id, tagName, attributes);
+            }
+        }
 
         if (lastSelector->relation() != CSSSelector::SubSelector)
             break;
     }
+    return lastSelector;
+}
 
-    if (!lastSelector)
-        return AddFeatures;
-    for (const CSSSelector* current = lastSelector->tagHistory(); current; current = current->tagHistory()) {
+void RuleFeatureSet::addFeaturesToInvalidationSets(const CSSSelector& selector, const Vector<AtomicString>& classes, AtomicString id, AtomicString tagName, const Vector<AtomicString>& attributes)
+{
+    for (const CSSSelector* current = &selector; current; current = current->tagHistory()) {
         if (DescendantInvalidationSet* invalidationSet = invalidationSetForSelector(*current)) {
             if (!id.isEmpty())
                 invalidationSet->addId(id);
             if (!tagName.isEmpty())
                 invalidationSet->addTagName(tagName);
             for (Vector<AtomicString>::const_iterator it = classes.begin(); it != classes.end(); ++it)
                 invalidationSet->addClass(*it);
             for (Vector<AtomicString>::const_iterator it = attributes.begin(); it != attributes.end(); ++it)
                 invalidationSet->addAttribute(*it);
+        } else if (current->pseudoType() == CSSSelector::PseudoHost) {
+            if (const CSSSelectorList* selectorList = current->selectorList()) {
+                for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(*selector))
+                    addFeaturesToInvalidationSets(*selector, classes, id, tagName, attributes);
+            }
         }
     }
-    return AddFeatures;
 }
 
 void RuleFeatureSet::addContentAttr(const AtomicString& attributeName)
 {
     DescendantInvalidationSet& invalidationSet = ensureAttributeInvalidationSet(attributeName);
     invalidationSet.setWholeSubtreeInvalid();
 }
 
 void RuleFeatureSet::collectFeaturesFromRuleData(const RuleData& ruleData)
 {
@@ skipping 187 matching lines @@
     if (node->isElementNode())
         m_pendingInvalidationMap.remove(toElement(node));
 }
 
 RuleFeatureSet::PendingInvalidationMap& RuleFeatureSet::pendingInvalidationMap()
 {
     return m_pendingInvalidationMap;
 }
 
 } // namespace WebCore