Introduce PseudoElementIdentifier

https://bugs.webkit.org/show_bug.cgi?id=268412
rdar://121959648

Reviewed by Darin Adler.

We want to separate this from PseudoElementRequest so we can re-use it in other places.

* Source/WebCore/WebCore.xcodeproj/project.pbxproj:
* Source/WebCore/rendering/RenderElement.cpp:
(WebCore::RenderElement::getUncachedPseudoStyle const):
* Source/WebCore/style/ElementRuleCollector.cpp:
(WebCore::Style::ElementRuleCollector::collectMatchingRules):
(WebCore::Style::ElementRuleCollector::ruleMatches):
(WebCore::Style::ElementRuleCollector::collectMatchingRulesForList):
(WebCore::Style::ElementRuleCollector::addAuthorKeyframeRules):
* Source/WebCore/style/PseudoElementIdentifier.h: Copied from Source/WebCore/style/PseudoElementRequest.h.
(WebCore::Style::PseudoElementIdentifier::PseudoElementIdentifier):
* Source/WebCore/style/PseudoElementRequest.h:
(WebCore::Style::PseudoElementRequest::PseudoElementRequest):
(WebCore::Style::PseudoElementRequest::identifier const):
(WebCore::Style::PseudoElementRequest::pseudoId const):
(WebCore::Style::PseudoElementRequest::pseudoElementNameArgument const):
(WebCore::Style::PseudoElementRequest::scrollbarState const):
* Source/WebCore/style/StyleResolver.cpp:
(WebCore::Style::Resolver::styleForPseudoElement):

Canonical link: https://commits.webkit.org/273809@main

Source/WebCore/WebCore.xcodeproj/project.pbxproj

@@ -1765,6 +1765,7 @@
 		48B0242A2B2A65AA0083D122 /* AXTextRun.h in Headers */ = {isa = PBXBuildFile; fileRef = 48B024282B2A65AA0083D122 /* AXTextRun.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		48B5BF3729CA691700FEBE3B /* AccessibilityRegionContext.h in Headers */ = {isa = PBXBuildFile; fileRef = 48B5BF3529CA691700FEBE3B /* AccessibilityRegionContext.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		48D0E12929F7329E00263857 /* ElementAnimationContext.h in Headers */ = {isa = PBXBuildFile; fileRef = 48D0E12829F7322900263857 /* ElementAnimationContext.h */; settings = {ATTRIBUTES = (Private, ); }; };
+		490D51012B698A8300C6B266 /* PseudoElementIdentifier.h in Headers */ = {isa = PBXBuildFile; fileRef = 490D51002B698A8300C6B266 /* PseudoElementIdentifier.h */; };
 		491342E32B43FFEF00FEEF18 /* CSSSelectorInlines.h in Headers */ = {isa = PBXBuildFile; fileRef = 491342DA2B43FAA800FEEF18 /* CSSSelectorInlines.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		491342E42B43FFEF00FEEF18 /* CSSSelectorEnums.h in Headers */ = {isa = PBXBuildFile; fileRef = 491342D92B43FAA700FEEF18 /* CSSSelectorEnums.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		493E5E0912D6420500020081 /* PlatformCALayerClient.h in Headers */ = {isa = PBXBuildFile; fileRef = 493E5E0812D6420500020081 /* PlatformCALayerClient.h */; settings = {ATTRIBUTES = (Private, ); }; };
@@ -10802,6 +10803,7 @@
 		48B5BF3629CA691700FEBE3B /* AccessibilityRegionContext.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = AccessibilityRegionContext.cpp; sourceTree = "<group>"; };
 		48C4E83C2B34D8380083460A /* AXTextRun.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = AXTextRun.cpp; sourceTree = "<group>"; };
 		48D0E12829F7322900263857 /* ElementAnimationContext.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = ElementAnimationContext.h; sourceTree = "<group>"; };
+		490D51002B698A8300C6B266 /* PseudoElementIdentifier.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = PseudoElementIdentifier.h; sourceTree = "<group>"; };
 		491342962B425C0100FEEF18 /* CSSPseudoSelectors.json */ = {isa = PBXFileReference; lastKnownFileType = text.json; path = CSSPseudoSelectors.json; sourceTree = "<group>"; };
 		491342972B425C0200FEEF18 /* process-css-pseudo-selectors.py */ = {isa = PBXFileReference; lastKnownFileType = text.script.python; path = "process-css-pseudo-selectors.py"; sourceTree = "<group>"; };
 		491342D92B43FAA700FEEF18 /* CSSSelectorEnums.h */ = {isa = PBXFileReference; explicitFileType = sourcecode.c.h; fileEncoding = 4; path = CSSSelectorEnums.h; sourceTree = "<group>"; };
@@ -35305,6 +35307,7 @@
 				E4ABABE22361A32900FA4345 /* PropertyCascade.h */,
 				E45A6C732417BA4C006E4CD5 /* PseudoClassChangeInvalidation.cpp */,
 				E45A6C762417BA59006E4CD5 /* PseudoClassChangeInvalidation.h */,
+				490D51002B698A8300C6B266 /* PseudoElementIdentifier.h */,
 				494265302B61F7E9000446D5 /* PseudoElementRequest.h */,
 				930A9D8629DA3EFF006CBF0E /* ResolvedStyle.h */,
 				E4863CFA23842E8700972158 /* RuleData.cpp */,
@@ -41244,6 +41247,7 @@
 				51A052561058874000CC9E95 /* ProtectionSpaceHash.h in Headers */,
 				E45A6C772417BA59006E4CD5 /* PseudoClassChangeInvalidation.h in Headers */,
 				FF945ECC161F7F3600971BC8 /* PseudoElement.h in Headers */,
+				490D51012B698A8300C6B266 /* PseudoElementIdentifier.h in Headers */,
 				494265312B61F7EA000446D5 /* PseudoElementRequest.h in Headers */,
 				57D8462E1FEAF69900CA3682 /* PublicKeyCredential.h in Headers */,
 				57303BE92009748D00355965 /* PublicKeyCredentialCreationOptions.h in Headers */,

Source/WebCore/rendering/RenderElement.cpp

@@ -1663,7 +1663,7 @@ const RenderStyle* RenderElement::getCachedPseudoStyle(PseudoId pseudo, const Re
 
 std::unique_ptr<RenderStyle> RenderElement::getUncachedPseudoStyle(const Style::PseudoElementRequest& pseudoElementRequest, const RenderStyle* parentStyle, const RenderStyle* ownStyle) const
 {
-    if (pseudoElementRequest.pseudoId < PseudoId::FirstInternalPseudoId && !ownStyle && !style().hasPseudoStyle(pseudoElementRequest.pseudoId))
+    if (pseudoElementRequest.pseudoId() < PseudoId::FirstInternalPseudoId && !ownStyle && !style().hasPseudoStyle(pseudoElementRequest.pseudoId()))
         return nullptr;
 
     if (!parentStyle) {

Source/WebCore/style/ElementRuleCollector.cpp

@@ -193,7 +193,7 @@ void ElementRuleCollector::collectMatchingRules(CascadeLevel level)
 
 void ElementRuleCollector::collectMatchingRules(const MatchRequest& matchRequest)
 {
-    ASSERT_WITH_MESSAGE(!(m_mode == SelectorChecker::Mode::CollectingRulesIgnoringVirtualPseudoElements && m_pseudoElementRequest.pseudoId != PseudoId::None), "When in StyleInvalidation or SharingRules, SelectorChecker does not try to match the pseudo ID. While ElementRuleCollector supports matching a particular pseudoId in this case, this would indicate a error at the call site since matching a particular element should be unnecessary.");
+    ASSERT_WITH_MESSAGE(!(m_mode == SelectorChecker::Mode::CollectingRulesIgnoringVirtualPseudoElements && m_pseudoElementRequest.pseudoId() != PseudoId::None), "When in StyleInvalidation or SharingRules, SelectorChecker does not try to match the pseudo ID. While ElementRuleCollector supports matching a particular pseudoId in this case, this would indicate a error at the call site since matching a particular element should be unnecessary.");
 
     auto& element = this->element();
     auto* shadowRoot = element.containingShadowRoot();
@@ -446,7 +446,7 @@ inline bool ElementRuleCollector::ruleMatches(const RuleData& ruleData, unsigned
     // This is limited to HTML only so we don't need to check the namespace (because of tag name match).
     auto matchBasedOnRuleHash = ruleData.matchBasedOnRuleHash();
     if (matchBasedOnRuleHash != MatchBasedOnRuleHash::None && element().isHTMLElement()) {
-        ASSERT_WITH_MESSAGE(m_pseudoElementRequest.pseudoId == PseudoId::None, "If we match based on the rule hash while collecting for a particular pseudo element ID, we would add incorrect rules for that pseudo element ID. We should never end in ruleMatches() with a pseudo element if the ruleData cannot match any pseudo element.");
+        ASSERT_WITH_MESSAGE(m_pseudoElementRequest.pseudoId() == PseudoId::None, "If we match based on the rule hash while collecting for a particular pseudo element ID, we would add incorrect rules for that pseudo element ID. We should never end in ruleMatches() with a pseudo element if the ruleData cannot match any pseudo element.");
 
         switch (matchBasedOnRuleHash) {
         case MatchBasedOnRuleHash::None:
@@ -479,7 +479,7 @@ inline bool ElementRuleCollector::ruleMatches(const RuleData& ruleData, unsigned
 
 #if !ASSERT_MSG_DISABLED
         unsigned ignoreSpecificity;
-        ASSERT_WITH_MESSAGE(!SelectorCompiler::ruleCollectorSimpleSelectorChecker(compiledSelector, &element(), &ignoreSpecificity) || m_pseudoElementRequest.pseudoId == PseudoId::None, "When matching pseudo elements, we should never compile a selector checker without context unless it cannot match anything.");
+        ASSERT_WITH_MESSAGE(!SelectorCompiler::ruleCollectorSimpleSelectorChecker(compiledSelector, &element(), &ignoreSpecificity) || m_pseudoElementRequest.pseudoId() == PseudoId::None, "When matching pseudo elements, we should never compile a selector checker without context unless it cannot match anything.");
 #endif
         bool selectorMatches = SelectorCompiler::ruleCollectorSimpleSelectorChecker(compiledSelector, &element(), &specificity);
 
@@ -491,9 +491,9 @@ inline bool ElementRuleCollector::ruleMatches(const RuleData& ruleData, unsigned
 #endif // ENABLE(CSS_SELECTOR_JIT)
 
     SelectorChecker::CheckingContext context(m_mode);
-    context.pseudoId = m_pseudoElementRequest.pseudoId;
-    context.scrollbarState = m_pseudoElementRequest.scrollbarState;
-    context.pseudoElementNameArgument = m_pseudoElementRequest.pseudoElementNameArgument;
+    context.pseudoId = m_pseudoElementRequest.pseudoId();
+    context.scrollbarState = m_pseudoElementRequest.scrollbarState();
+    context.pseudoElementNameArgument = m_pseudoElementRequest.pseudoElementNameArgument();
     context.styleScopeOrdinal = styleScopeOrdinal;
     context.selectorMatchingState = m_selectorMatchingState;
     context.scope = scopingRoot;
@@ -535,7 +535,7 @@ void ElementRuleCollector::collectMatchingRulesForList(const RuleSet::RuleDataVe
         if (UNLIKELY(!ruleData.isEnabled()))
             continue;
 
-        if (!ruleData.canMatchPseudoElement() && m_pseudoElementRequest.pseudoId != PseudoId::None)
+        if (!ruleData.canMatchPseudoElement() && m_pseudoElementRequest.pseudoId() != PseudoId::None)
             continue;
 
         if (m_selectorMatchingState && m_selectorMatchingState->selectorFilter.fastRejectSelector(ruleData.descendantSelectorIdentifierHashes()))
@@ -843,7 +843,7 @@ void ElementRuleCollector::addMatchedProperties(MatchedProperties&& matchedPrope
 void ElementRuleCollector::addAuthorKeyframeRules(const StyleRuleKeyframe& keyframe)
 {
     ASSERT(m_result->authorDeclarations.isEmpty());
-    m_result->authorDeclarations.append({ keyframe.properties(), SelectorChecker::MatchAll, propertyAllowlistForPseudoId(m_pseudoElementRequest.pseudoId) });
+    m_result->authorDeclarations.append({ keyframe.properties(), SelectorChecker::MatchAll, propertyAllowlistForPseudoId(m_pseudoElementRequest.pseudoId()) });
 }
 
 }

Source/WebCore/style/PseudoElementIdentifier.h

@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2024 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include "RenderStyleConstants.h"
+#include <wtf/text/AtomString.h>
+
+namespace WebCore::Style {
+
+struct PseudoElementIdentifier {
+    PseudoId pseudoId;
+
+    // highlight name for ::highlight or view transition name for view transition pseudo elements.
+    AtomString pseudoElementNameArgument { nullAtom() };
+};
+
+} // namespace WebCore

Source/WebCore/style/PseudoElementRequest.h

@@ -25,6 +25,7 @@
 
 #pragma once
 
+#include "PseudoElementIdentifier.h"
 #include "RenderStyleConstants.h"
 #include <wtf/text/AtomString.h>
 
@@ -33,23 +34,30 @@ namespace WebCore::Style {
 class PseudoElementRequest {
 public:
     PseudoElementRequest(PseudoId pseudoId, std::optional<StyleScrollbarState> scrollbarState = std::nullopt)
-        : pseudoId(pseudoId)
-        , scrollbarState(scrollbarState)
+        : m_identifier({ pseudoId })
+        , m_scrollbarState(scrollbarState)
     {
     }
 
     PseudoElementRequest(PseudoId pseudoId, const AtomString& pseudoElementNameArgument)
-        : pseudoId(pseudoId)
-        , pseudoElementNameArgument(pseudoElementNameArgument)
+        : m_identifier({ pseudoId, pseudoElementNameArgument })
     {
         ASSERT(pseudoId == PseudoId::Highlight || pseudoId == PseudoId::ViewTransitionGroup || pseudoId == PseudoId::ViewTransitionImagePair || pseudoId == PseudoId::ViewTransitionOld || pseudoId == PseudoId::ViewTransitionNew);
     }
 
-    PseudoId pseudoId;
-    std::optional<StyleScrollbarState> scrollbarState;
+    PseudoElementRequest(const PseudoElementIdentifier& pseudoElementIdentifier)
+        : m_identifier(pseudoElementIdentifier)
+    {
+    }
+
+    const PseudoElementIdentifier& identifier() const { return m_identifier; }
+    PseudoId pseudoId() const { return m_identifier.pseudoId; }
+    const AtomString& pseudoElementNameArgument() const { return m_identifier.pseudoElementNameArgument; }
+    const std::optional<StyleScrollbarState>& scrollbarState() const { return m_scrollbarState; }
 
-    // highlight name for ::highlight or view transition name for view transition pseudo elements.
-    AtomString pseudoElementNameArgument;
+private:
+    PseudoElementIdentifier m_identifier;
+    std::optional<StyleScrollbarState> m_scrollbarState;
 };
 
 } // namespace WebCore

Source/WebCore/style/StyleResolver.cpp

@@ -484,9 +484,9 @@ std::optional<ResolvedStyle> Resolver::styleForPseudoElement(const Element& elem
     if (collector.matchResult().isEmpty())
         return { };
 
-    state.style()->setPseudoElementType(pseudoElementRequest.pseudoId);
-    if (!pseudoElementRequest.pseudoElementNameArgument.isNull())
-        state.style()->setPseudoElementNameArgument(pseudoElementRequest.pseudoElementNameArgument);
+    state.style()->setPseudoElementType(pseudoElementRequest.pseudoId());
+    if (!pseudoElementRequest.pseudoElementNameArgument().isNull())
+        state.style()->setPseudoElementNameArgument(pseudoElementRequest.pseudoElementNameArgument());
 
     applyMatchedProperties(state, collector.matchResult());