Clear StyleResolverState after each resolve.

Source/core/css/resolver/StyleResolver.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, 2013 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 996 matching lines @@
         if (!s_styleNotYetAvailable) {
             s_styleNotYetAvailable = RenderStyle::create().leakRef();
             s_styleNotYetAvailable->setDisplay(NONE);
             s_styleNotYetAvailable->font().update(m_fontSelector);
         }
         element->document()->setHasNodesWithPlaceholderStyle();
         return s_styleNotYetAvailable;
     }
 
     StyleResolverState& state = m_state;
-    state.initForStyleResolve(document(), element, defaultParent, regionForStyling);
+    ScopedStyleResolution resolution(&state, document(), element, defaultParent, regionForStyling);

[eseidel, 2013/07/12 22:05:42]

This seems somewhat confusingly named.  ScopedStyles are a separate concept from
what you're doing here, or?

[Jeffrey Yasskin, 2013/07/12 22:59:05]

Yeah; switched to StyleResolveScope. I'm hopeful that I can make
StyleResolverState a local object in the next change, so the exact name for this
type may not matter that much.

     if (sharingBehavior == AllowStyleSharing && !state.distributedToInsertionPoint() && state.parentStyle()) {
-        RenderStyle* sharedStyle = locateSharedStyle(state.elementContext());
-        if (sharedStyle) {
-            state.clear();
-            return sharedStyle;
-        }
+        RefPtr<RenderStyle> sharedStyle = locateSharedStyle(state.elementContext());
+        if (sharedStyle)
+            return sharedStyle.release();
     }
 
     if (state.parentStyle()) {
         state.setStyle(RenderStyle::create());
         state.style()->inheritFrom(state.parentStyle(), isAtShadowBoundary(element) ? RenderStyle::AtShadowBoundary : RenderStyle::NotAtShadowBoundary);
     } else {
         state.setStyle(defaultStyleForElement());
         state.setParentStyle(RenderStyle::clone(state.style()));
     }
     // contenteditable attribute (implemented by -webkit-user-modify) should
@@ skipping 30 matching lines @@
         if (matchingBehavior == MatchOnlyUserAgentRules)
             matchUARules(collector);
         else
             matchAllRules(collector, m_matchAuthorAndUserStyles, matchingBehavior != MatchAllRulesExcludingSMIL);
 
         applyMatchedProperties(collector.matchedResult(), element);
     }
     // Clean up our style object's display and text decorations (among other fixups).
     adjustRenderStyle(state.style(), state.parentStyle(), element);
 
-    state.clear(); // Clear out for the next resolve.
-
     document()->didAccessStyleResolver();
 
     // FIXME: Shouldn't this be on RenderBody::styleDidChange?
     if (element->hasTagName(bodyTag))
         document()->textLinkColors().setTextColor(state.style()->visitedDependentColor(CSSPropertyColor));
 
     // Now return the style.
     return state.takeStyle();
 }
 
-PassRefPtr<RenderStyle> StyleResolver::styleForKeyframe(const RenderStyle* elementStyle, const StyleKeyframe* keyframe, KeyframeValue& keyframeValue)
+PassRefPtr<RenderStyle> StyleResolver::styleForKeyframe(Element* e, const RenderStyle* elementStyle, const StyleKeyframe* keyframe, KeyframeValue& keyframeValue)
 {
+    ScopedStyleResolution resolution(&m_state, document(), e);
+
     MatchResult result;
     if (keyframe->properties())
         result.addMatchedProperties(keyframe->properties());
 
     StyleResolverState& state = m_state;
     ASSERT(!state.style());
 
     // Create the style
     state.setStyle(RenderStyle::clone(elementStyle));
     state.setLineHeightValue(0);
@@ skipping 55 matching lines @@
     KeyframesRuleMap::iterator it = m_keyframesRuleMap.find(list.animationName().impl());
     if (it == m_keyframesRuleMap.end())
         return;
 
     const StyleRuleKeyframes* keyframesRule = it->value.get();
 
     // Construct and populate the style for each keyframe
     const Vector<RefPtr<StyleKeyframe> >& keyframes = keyframesRule->keyframes();
     for (unsigned i = 0; i < keyframes.size(); ++i) {
         // Apply the declaration to the style. This is a simplified version of the logic in styleForElement
-        m_state.initForStyleResolve(document(), e);
-
         const StyleKeyframe* keyframe = keyframes[i].get();
 
         KeyframeValue keyframeValue(0, 0);
-        keyframeValue.setStyle(styleForKeyframe(elementStyle, keyframe, keyframeValue));
+        keyframeValue.setStyle(styleForKeyframe(e, elementStyle, keyframe, keyframeValue));
 
         // Add this keyframe style to all the indicated key times
         Vector<float> keys;
         keyframe->getKeys(keys);
         for (size_t keyIndex = 0; keyIndex < keys.size(); ++keyIndex) {
             keyframeValue.setKey(keys[keyIndex]);
             list.insert(keyframeValue);
         }
     }
 
     // If the 0% keyframe is missing, create it (but only if there is at least one other keyframe)
     int initialListSize = list.size();
     if (initialListSize > 0 && list[0].key()) {
         static StyleKeyframe* zeroPercentKeyframe;
         if (!zeroPercentKeyframe) {
             zeroPercentKeyframe = StyleKeyframe::create().leakRef();
             zeroPercentKeyframe->setKeyText("0%");
         }
         KeyframeValue keyframeValue(0, 0);
-        keyframeValue.setStyle(styleForKeyframe(elementStyle, zeroPercentKeyframe, keyframeValue));
+        keyframeValue.setStyle(styleForKeyframe(e, elementStyle, zeroPercentKeyframe, keyframeValue));
         list.insert(keyframeValue);
     }
 
     // If the 100% keyframe is missing, create it (but only if there is at least one other keyframe)
     if (initialListSize > 0 && (list[list.size() - 1].key() != 1)) {
         static StyleKeyframe* hundredPercentKeyframe;
         if (!hundredPercentKeyframe) {
             hundredPercentKeyframe = StyleKeyframe::create().leakRef();
             hundredPercentKeyframe->setKeyText("100%");
         }
         KeyframeValue keyframeValue(1, 0);
-        keyframeValue.setStyle(styleForKeyframe(elementStyle, hundredPercentKeyframe, keyframeValue));
+        keyframeValue.setStyle(styleForKeyframe(e, elementStyle, hundredPercentKeyframe, keyframeValue));
         list.insert(keyframeValue);
     }
 }
 
 PassRefPtr<RenderStyle> StyleResolver::pseudoStyleForElement(Element* e, const PseudoStyleRequest& pseudoStyleRequest, RenderStyle* parentStyle)
 {
     ASSERT(parentStyle);
     if (!e)
         return 0;
 
     StyleResolverState& state = m_state;
 
-    state.initForStyleResolve(document(), e, parentStyle);
+    ScopedStyleResolution resolution(&state, document(), e, parentStyle);
 
     if (pseudoStyleRequest.allowsInheritance(state.parentStyle())) {
         state.setStyle(RenderStyle::create());
         state.style()->inheritFrom(state.parentStyle());
     } else {
         state.setStyle(defaultStyleForElement());
         state.setParentStyle(RenderStyle::clone(state.style()));
     }
 
     // Since we don't use pseudo-elements in any of our quirk/print
@@ skipping 24 matching lines @@
     m_styleResourceLoader.loadPendingResources(state.style(), state.elementStyleResources());
 
     document()->didAccessStyleResolver();
 
     // Now return the style.
     return state.takeStyle();
 }
 
 PassRefPtr<RenderStyle> StyleResolver::styleForPage(int pageIndex)
 {
-    m_state.initForStyleResolve(document(), document()->documentElement()); // m_rootElementStyle will be set to the document style.
+    ScopedStyleResolution resolution(&m_state, document(), document()->documentElement()); // m_rootElementStyle will be set to the document style.
 
     m_state.setStyle(RenderStyle::create());
     m_state.style()->inheritFrom(m_state.rootElementStyle());
 
     PageRuleCollector collector(m_state, pageIndex);
 
     collector.matchPageRules(CSSDefaultStyleSheets::defaultPrintStyle);
     collector.matchPageRules(m_ruleSets.userStyle());
 
     if (ScopedStyleResolver* scopedResolver = m_styleTree.scopedStyleResolverForDocument())
@@ skipping 435 matching lines @@
 PassRefPtr<CSSRuleList> StyleResolver::styleRulesForElement(Element* e, unsigned rulesToInclude)
 {
     return pseudoStyleRulesForElement(e, NOPSEUDO, rulesToInclude);
 }
 
 PassRefPtr<CSSRuleList> StyleResolver::pseudoStyleRulesForElement(Element* e, PseudoId pseudoId, unsigned rulesToInclude)
 {
     if (!e || !e->document()->haveStylesheetsLoaded())
         return 0;
 
-    m_state.initForStyleResolve(document(), e);
+    ScopedStyleResolution resolution(&m_state, document(), e);
 
     ElementRuleCollector collector(m_state.elementContext(), m_selectorFilter, m_state.style(), m_inspectorCSSOMWrappers);
     collector.setMode(SelectorChecker::CollectingRules);
     collector.setPseudoStyleRequest(PseudoStyleRequest(pseudoId));
 
     if (rulesToInclude & UAAndUserCSSRules) {
         // First we match rules from the user agent sheet.
         matchUARules(collector);
 
         // Now we check user sheet rules.
@@ skipping 305 matching lines @@
 
     ASSERT(!state.fontDirty());
 
     if (cachedMatchedProperties || !cacheHash)
         return;
     if (!MatchedPropertiesCache::isCacheable(state.element(), state.style(), state.parentStyle()))
         return;
     m_matchedPropertiesCache.add(state.style(), state.parentStyle(), cacheHash, matchResult);
 }
 
-void StyleResolver::applyPropertyToStyle(CSSPropertyID id, CSSValue* value, RenderStyle* style)
+CSSPropertyValue::CSSPropertyValue(CSSPropertyID id, const StylePropertySet& propertySet)
+    : property(id), value(propertySet.getPropertyCSSValue(id).get())
+{ }
+
+void StyleResolver::applyPropertiesToStyle(const CSSPropertyValue* properties, size_t count, RenderStyle* style)
 {
-    m_state.initForStyleResolve(document(), 0, style);
+    ScopedStyleResolution resolution(&m_state, document(), 0, style);
     m_state.setStyle(style);
-    applyPropertyToCurrentStyle(id, value);
-}
-
-void StyleResolver::applyPropertyToCurrentStyle(CSSPropertyID id, CSSValue* value)
-{
-    if (value)
-        applyProperty(id, value);
+    for (size_t i = 0; i < count; ++i) {
+        if (properties[i].value) {
+            // As described in BUG66291, setting font-size and line-height on a font may entail a CSSPrimitiveValue::computeLengthDouble call,
+            // which assumes the fontMetrics are available for the affected font, otherwise a crash occurs (see http://trac.webkit.org/changeset/96122).
+            // The updateFont() call below updates the fontMetrics and ensure the proper setting of font-size and line-height.
+            switch (properties[i].property) {
+            case CSSPropertyFontSize:
+            case CSSPropertyLineHeight:
+                updateFont();
+                break;
+            default:
+                break;
+            }
+            applyProperty(properties[i].property, properties[i].value);
+        }
+    }
 }
 
 static bool hasVariableReference(CSSValue* value)
 {
     if (value->isPrimitiveValue()) {
         CSSPrimitiveValue* primitiveValue = toCSSPrimitiveValue(value);
         return primitiveValue->hasVariableReference();
     }
 
     if (value->isCalculationValue())
@@ skipping 203 matching lines @@
     info.addMember(m_state, "state");
 
     // FIXME: move this to a place where it would be called only once?
     info.addMember(CSSDefaultStyleSheets::defaultStyle, "defaultStyle");
     info.addMember(CSSDefaultStyleSheets::defaultQuirksStyle, "defaultQuirksStyle");
     info.addMember(CSSDefaultStyleSheets::defaultPrintStyle, "defaultPrintStyle");
     info.addMember(CSSDefaultStyleSheets::defaultViewSourceStyle, "defaultViewSourceStyle");
 }
 
 } // namespace WebCore