CSS Custom Properties (Variables)

Source/core/css/CSSCalculationValue.cpp

Index: Source/core/css/CSSCalculationValue.cpp
diff --git a/Source/core/css/CSSCalculationValue.cpp b/Source/core/css/CSSCalculationValue.cpp
index 998fba4d322d019fc2069e1f42690de038ab1169..9208235947c97b683929a7090e7c37d741855d20 100644
--- a/Source/core/css/CSSCalculationValue.cpp
+++ b/Source/core/css/CSSCalculationValue.cpp
@@ -32,6 +32,7 @@
 #include "core/css/CSSCalculationValue.h"
 
 #include "core/css/CSSPrimitiveValueMappings.h"
+#include "core/css/parser/CSSPropertyParser.h"
 #include "core/css/resolver/StyleResolver.h"
 #include "wtf/MathExtras.h"
 #include "wtf/OwnPtr.h"
@@ -80,6 +81,8 @@ static CalculationCategory unitCategory(CSSPrimitiveValue::UnitType type)
     case CSSPrimitiveValue::CSS_HZ:
     case CSSPrimitiveValue::CSS_KHZ:
         return CalcFrequency;
+    case CSSPrimitiveValue::CSS_VARIABLE_REFERENCE:
+        return CalcVariable;
     default:
         return CalcOther;
     }
@@ -135,6 +138,7 @@ static bool hasDoubleValue(CSSPrimitiveValue::UnitType type)
     case CSSPrimitiveValue::CSS_PROPERTY_ID:
     case CSSPrimitiveValue::CSS_VALUE_ID:
     case CSSPrimitiveValue::CSS_QEM:
+    case CSSPrimitiveValue::CSS_VARIABLE_REFERENCE:
         return false;
     };
     ASSERT_NOT_REACHED();
@@ -243,6 +247,7 @@ public:
         case CalcPercentLength:
         case CalcPercentNumber:
         case CalcTime:
+        case CalcVariable:
         case CalcOther:
             ASSERT_NOT_REACHED();
             break;
@@ -308,6 +313,9 @@ static CalculationCategory determineCategory(const CSSCalcExpressionNode& leftSi
     if (leftCategory == CalcOther || rightCategory == CalcOther)
         return CalcOther;
 
+    if (leftCategory == CalcVariable || rightCategory == CalcVariable)
+        return CalcVariable;
+
     switch (op) {
     case CalcAdd:
     case CalcSubtract:
@@ -529,6 +537,8 @@ public:
             return CSSPrimitiveValue::CSS_MS;
         case CalcFrequency:
             return CSSPrimitiveValue::CSS_HZ;
+        case CalcVariable:
+            return CSSPrimitiveValue::CSS_VARIABLE_REFERENCE;
         case CalcPercentLength:
         case CalcPercentNumber:
         case CalcOther:
@@ -635,10 +645,21 @@ private:
     bool parseValue(CSSParserValueList* tokens, unsigned* index, Value* result)
     {
         CSSParserValue* parserValue = tokens->valueAt(*index);
-        if (parserValue->unit >= CSSParserValue::Operator)
-            return false;
+
+        if (parserValue->unit >= CSSParserValue::Operator) {
+            // We still have to check for variables, which are parser values
+            if (!RuntimeEnabledFeatures::cssVariablesEnabled() || !CSSPropertyParser::isVariableReference(parserValue))
+                return false;
+
+            result->value = CSSCalcPrimitiveValue::create(
+                CSSPrimitiveValue::create(parserValue->function->args->valueAt(0)->string, CSSPrimitiveValue::CSS_VARIABLE_REFERENCE), parserValue->isInt);
+            ++*index;
+
+            return true;
+        }
 
         CSSPrimitiveValue::UnitType type = static_cast<CSSPrimitiveValue::UnitType>(parserValue->unit);
+
         if (unitCategory(type) == CalcOther)
             return false;