CSS Custom Properties (Variables)

Source/core/css/parser/CSSParserImpl.cpp

Index: Source/core/css/parser/CSSParserImpl.cpp
diff --git a/Source/core/css/parser/CSSParserImpl.cpp b/Source/core/css/parser/CSSParserImpl.cpp
index 9998d53ba617b90460269c363ef4511dde2b1f99..3687ad62eda3fa585781e970e74d009a1e35aad5 100644
--- a/Source/core/css/parser/CSSParserImpl.cpp
+++ b/Source/core/css/parser/CSSParserImpl.cpp
@@ -7,6 +7,7 @@
 
 #include "core/css/CSSKeyframesRule.h"
 #include "core/css/CSSStyleSheet.h"
+#include "core/css/CSSVariableValue.h"
 #include "core/css/StylePropertySet.h"
 #include "core/css/StyleRuleImport.h"
 #include "core/css/StyleRuleKeyframe.h"
@@ -19,6 +20,7 @@
 #include "core/css/parser/CSSSelectorParser.h"
 #include "core/css/parser/CSSSupportsParser.h"
 #include "core/css/parser/CSSTokenizer.h"
+#include "core/css/parser/CSSVariableParser.h"
 #include "core/css/parser/MediaQueryParser.h"
 #include "core/dom/Document.h"
 #include "core/dom/Element.h"
@@ -57,7 +59,7 @@ static inline void filterProperties(bool important, const WillBeHeapVector<CSSPr
         if (property.isImportant() != important)
             continue;
         const unsigned propertyIDIndex = property.id() - firstCSSProperty;
-        if (seenProperties.get(propertyIDIndex))
+        if (seenProperties.get(propertyIDIndex) && property.id() != CSSPropertyVariable)
             continue;
         seenProperties.set(propertyIDIndex);
         output[--unusedEntries] = property;
@@ -656,7 +658,8 @@ void CSSParserImpl::consumeDeclaration(CSSParserTokenRange range, StyleRule::Typ
     CSSParserTokenRange rangeCopy = range; // For inspector callbacks
 
     ASSERT(range.peek().type() == IdentToken);
-    CSSPropertyID unresolvedProperty = range.consumeIncludingWhitespace().parseAsUnresolvedCSSPropertyID();
+    CSSParserToken token = range.consumeIncludingWhitespace();
+    CSSPropertyID unresolvedProperty = token.parseAsUnresolvedCSSPropertyID();
     if (range.consume().type() != ColonToken)
         return; // Parse error
 
@@ -665,6 +668,14 @@ void CSSParserImpl::consumeDeclaration(CSSParserTokenRange range, StyleRule::Typ
     const CSSParserToken* last = range.end() - 1;
     while (last->type() == WhitespaceToken)
         --last;
+
+    if (unresolvedProperty == CSSPropertyVariable) {
+        ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
+        AtomicString variableName = token.value();
+        m_styleSheet->parserSetUsesVariables(true);
+        consumeVariableDeclarationValue(range.makeSubRange(&range.peek(), declarationValueEnd), variableName);
+        return;
+    }
     if (last->type() == IdentToken && last->valueEqualsIgnoringCase("important")) {
         --last;
         while (last->type() == WhitespaceToken)
@@ -685,6 +696,7 @@ void CSSParserImpl::consumeDeclaration(CSSParserTokenRange range, StyleRule::Typ
         m_observerWrapper->observer().observeProperty(
             m_observerWrapper->startOffset(rangeCopy), m_observerWrapper->endOffset(rangeCopy),
             important, m_parsedProperties.size() != propertiesCount);
+            consumeDeclarationValue(range.makeSubRange(&range.peek(), declarationValueEnd), unresolvedProperty, important, ruleType);
         return;
     }
 
@@ -694,14 +706,42 @@ void CSSParserImpl::consumeDeclaration(CSSParserTokenRange range, StyleRule::Typ
     consumeDeclarationValue(range.makeSubRange(&range.peek(), declarationValueEnd), unresolvedProperty, important, ruleType);
 }
 
+void CSSParserImpl::consumeVariableDeclarationValue(CSSParserTokenRange range, const AtomicString& variableName)
+{
+    switch (CSSVariableParser::parseVariableDefinition(range)) {
+    case CSSVariableParser::Invalid:
+        return;
+    case CSSVariableParser::Variable:
+        m_parsedProperties.append(CSSProperty(CSSPropertyVariable,
+            CSSVariableValue::create(variableName, CSSVariableData::create(range, false))));
+        return;
+    case CSSVariableParser::VariableWithReferences:
+        m_parsedProperties.append(CSSProperty(CSSPropertyVariable,
+            CSSVariableValue::create(variableName, CSSVariableData::create(range, true))));
+        return;
+    case CSSVariableParser::Initial:
+        m_parsedProperties.append(CSSProperty(CSSPropertyVariable,
+            CSSVariableValue::create(variableName, CSSValueInitial)));
+        return;
+    case CSSVariableParser::Inherit:
+        m_parsedProperties.append(CSSProperty(CSSPropertyVariable,
+            CSSVariableValue::create(variableName, CSSValueInherit)));
+        return;
+    }
+}
+
 void CSSParserImpl::consumeDeclarationValue(CSSParserTokenRange range, CSSPropertyID unresolvedProperty, bool important, StyleRule::Type ruleType)
 {
-    bool usesRemUnits;
-    CSSParserValueList valueList(range, usesRemUnits);
+    bool usesRemUnits, usesVariables;
+    CSSParserValueList valueList(range, usesRemUnits, usesVariables);
     if (!valueList.size())
         return; // Parser error
-    if (usesRemUnits && m_styleSheet)
-        m_styleSheet->parserSetUsesRemUnits(true);
+    if (m_styleSheet) {
+        if (usesRemUnits)
+            m_styleSheet->parserSetUsesRemUnits(true);
+        if (usesVariables)
+            m_styleSheet->parserSetUsesVariables(true);
+    }
     CSSPropertyParser::parseValue(unresolvedProperty, important, &valueList, m_context, m_parsedProperties, ruleType);
 }