CSS Custom Properties (Variables)

Source/core/css/resolver/StyleBuilderCustom.cpp

Index: Source/core/css/resolver/StyleBuilderCustom.cpp
diff --git a/Source/core/css/resolver/StyleBuilderCustom.cpp b/Source/core/css/resolver/StyleBuilderCustom.cpp
index eefd6cc6d4ca7854247e16577902c80b892926b9..7f8a92c801839282923f0e2d10ca387a339aaf28 100644
--- a/Source/core/css/resolver/StyleBuilderCustom.cpp
+++ b/Source/core/css/resolver/StyleBuilderCustom.cpp
@@ -52,10 +52,16 @@
 #include "core/css/CSSPathValue.h"
 #include "core/css/CSSPrimitiveValueMappings.h"
 #include "core/css/CSSPropertyMetadata.h"
+#include "core/css/CSSReflectValue.h"
+#include "core/css/CSSVariableValue.h"
 #include "core/css/Counter.h"
 #include "core/css/Pair.h"
 #include "core/css/StylePropertySet.h"
 #include "core/css/StyleRule.h"
+#include "core/css/parser/CSSParser.h"
+#include "core/css/parser/CSSParserTokenRange.h"
+#include "core/css/parser/CSSPropertyParser.h"
+#include "core/css/resolver/CSSVariableResolver.h"
 #include "core/css/resolver/ElementStyleResources.h"
 #include "core/css/resolver/FilterOperationResolver.h"
 #include "core/css/resolver/FontBuilder.h"
@@ -104,8 +110,18 @@ static inline bool isValidVisitedLinkProperty(CSSPropertyID id)
 
 } // namespace
 
+static bool hasVariableReference(CSSValue* value)
+{
+    return value->isPrimitiveValue() && toCSSPrimitiveValue(value)->primitiveType() == CSSPrimitiveValue::CSS_VARIABLE_REFERENCE;
+}
+
 void StyleBuilder::applyProperty(CSSPropertyID id, StyleResolverState& state, CSSValue* value)
 {
+    if (RuntimeEnabledFeatures::cssVariablesEnabled() /*&& state.documentUsesCSSVariables()*/ && id != CSSPropertyVariable && hasVariableReference(value)) {
+        CSSVariableResolver::resolveAndApplyVariableReferences(state, id, toCSSPrimitiveValue(value));
+        return;
+    }
+
     ASSERT_WITH_MESSAGE(!isShorthandProperty(id), "Shorthand property id = %d wasn't expanded at parsing time", id);
 
     bool isInherit = state.parentNode() && value->isInheritedValue();
@@ -798,6 +814,47 @@ void StyleBuilderFunctions::applyValueCSSPropertyWebkitTextOrientation(StyleReso
     state.setTextOrientation(*toCSSPrimitiveValue(value));
 }
 
+void StyleBuilderFunctions::applyValueCSSPropertyVariable(StyleResolverState& state, CSSValue* value)
+{
+    CSSVariableValue* varVal = toCSSVariableValue(value);
+    if (state.style()->variables()) {
+        switch (varVal->id()) {
+        case CSSValueInitial:
+            state.style()->variables()->removeVariable(varVal->name());
+            break;
+        case CSSValueInherit: {
+            StyleVariableData* parentVariables = state.parentStyle()->variables();
+            if (!parentVariables)
+                return;
+            CSSVariableData* value = parentVariables->getVariable(varVal->name());
+            if (!value)
+                return;
+            state.style()->variables()->setVariable(varVal->name(), value);
+            break;
+        }
+        case CSSValueInternalVariableValue:
+            state.style()->variables()->setVariable(varVal->name(), varVal->value());
+        break;
+        default:
+            ASSERT_NOT_REACHED();
+        }
+    } else if (varVal->id() == CSSValueInternalVariableValue) {
+        RefPtr<StyleVariableData> variableData = state.parentStyle()->variables() ? state.parentStyle()->variables()->copy() : StyleVariableData::create();
+        variableData->setVariable(varVal->name(), varVal->value());
+        state.style()->setVariables(variableData.release());
+    }
+}
+
+void StyleBuilderFunctions::applyInheritCSSPropertyVariable(StyleResolverState& state)
+{
+    ASSERT_NOT_REACHED();
+}
+
+void StyleBuilderFunctions::applyInitialCSSPropertyVariable(StyleResolverState& state)
+{
+    ASSERT_NOT_REACHED();
+}

[alancutter (OOO until 2018), 2015/06/26 06:56:08]

Can we use the regular StyleBuilder machinery for handling initial/inherit
instead of handling everything in applyValueCSSPropertyVariable()?

+
 void StyleBuilderFunctions::applyInheritCSSPropertyBaselineShift(StyleResolverState& state)
 {
     const SVGComputedStyle& parentSvgStyle = state.parentStyle()->svgStyle();