CSS Custom Properties (Variables)

third_party/WebKit/Source/core/css/parser/CSSParserImpl.cpp

Index: third_party/WebKit/Source/core/css/parser/CSSParserImpl.cpp
diff --git a/third_party/WebKit/Source/core/css/parser/CSSParserImpl.cpp b/third_party/WebKit/Source/core/css/parser/CSSParserImpl.cpp
index f0da1b94a74d9a419301b402ace11c45da31f176..c97508d1e96a3e1376b38fdc6139b2ed61d0e0bc 100644
--- a/third_party/WebKit/Source/core/css/parser/CSSParserImpl.cpp
+++ b/third_party/WebKit/Source/core/css/parser/CSSParserImpl.cpp
@@ -5,6 +5,7 @@
 #include "config.h"
 #include "core/css/parser/CSSParserImpl.h"
 
+#include "core/css/CSSCustomPropertyDeclaration.h"
 #include "core/css/CSSKeyframesRule.h"
 #include "core/css/CSSStyleSheet.h"
 #include "core/css/StylePropertySet.h"
@@ -18,7 +19,7 @@
 #include "core/css/parser/CSSPropertyParser.h"
 #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"
@@ -55,8 +56,9 @@ static inline void filterProperties(bool important, const WillBeHeapVector<CSSPr
         const CSSProperty& property = input[i];
         if (property.isImportant() != important)
             continue;
-        const unsigned propertyIDIndex = property.id() - firstCSSProperty;
-        if (seenProperties.get(propertyIDIndex))
+        // CSSPropertyVariable is asserted to be one number before the firstCSSProperty. We need to include it here.
+        const unsigned propertyIDIndex = property.id() - CSSPropertyVariable;

[Timothy Loh, 2015/09/30 02:09:27]

This looks wrong, won't the last property access outside the range of the
bitarray? We don't need to set in the bitarray for variables, so just checking
for variables separately should work.

+        if (seenProperties.get(propertyIDIndex) && property.id() != CSSPropertyVariable)
             continue;
         seenProperties.set(propertyIDIndex);
         output[--unusedEntries] = property;
@@ -660,12 +662,25 @@ void CSSParserImpl::consumeDeclarationList(CSSParserTokenRange range, StyleRule:
     }
 }
 
+template <typename CharacterType>
+static bool isCustomProperty(const CharacterType* propertyName, unsigned length)
+{
+    return (length >= 2 && propertyName[0] == '-' && propertyName[1] == '-');
+}
+
+inline bool isCustomProperty(CSSParserToken token)

[Timothy Loh, 2015/09/30 02:09:27]

This is duplicated between here and CSSVariableParser, can we share them? (The
other one looks better since it doesn't have templates)

+{
+    CSSParserString string = token.value();
+    return string.is8Bit() ? isCustomProperty(string.characters8(), string.length()) : isCustomProperty(string.characters16(), string.length());
+}
+
 void CSSParserImpl::consumeDeclaration(CSSParserTokenRange range, StyleRule::Type ruleType)
 {
     CSSParserTokenRange rangeCopy = range; // For inspector callbacks
 
     ASSERT(range.peek().type() == IdentToken);
-    CSSPropertyID unresolvedProperty = range.consumeIncludingWhitespace().parseAsUnresolvedCSSPropertyID();
+    const CSSParserToken& token = range.consumeIncludingWhitespace();
+    CSSPropertyID unresolvedProperty = token.parseAsUnresolvedCSSPropertyID();
     if (range.consume().type() != ColonToken)
         return; // Parse error
 
@@ -683,6 +698,11 @@ void CSSParserImpl::consumeDeclaration(CSSParserTokenRange range, StyleRule::Typ
             declarationValueEnd = last;
         }
     }
+    if (RuntimeEnabledFeatures::cssVariablesEnabled() && unresolvedProperty == CSSPropertyInvalid && isCustomProperty(token)) {
+        AtomicString variableName = token.value();
+        consumeVariableDeclarationValue(range.makeSubRange(&range.peek(), declarationValueEnd), variableName, important);
+        return;
+    }
 
     if (important && (ruleType == StyleRule::FontFace || ruleType == StyleRule::Keyframes))
         return;
@@ -703,6 +723,12 @@ void CSSParserImpl::consumeDeclaration(CSSParserTokenRange range, StyleRule::Typ
     consumeDeclarationValue(range.makeSubRange(&range.peek(), declarationValueEnd), unresolvedProperty, important, ruleType);
 }
 
+void CSSParserImpl::consumeVariableDeclarationValue(CSSParserTokenRange range, const AtomicString& variableName, bool important)
+{
+    if (PassRefPtrWillBeRawPtr<CSSCustomPropertyDeclaration> value = CSSVariableParser::parseDeclarationValue(variableName, range))

[Timothy Loh, 2015/09/30 02:09:28]

I think this is supposed to be:

if (RefPtr..<> value)
   ... value.release()

+        m_parsedProperties.append(CSSProperty(CSSPropertyVariable, value, important));
+}
+
 void CSSParserImpl::consumeDeclarationValue(CSSParserTokenRange range, CSSPropertyID unresolvedProperty, bool important, StyleRule::Type ruleType)
 {
     CSSPropertyParser::parseValue(unresolvedProperty, important, range, m_context, m_parsedProperties, ruleType);