Skeleton implementation of CSS Properties and Values API

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

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/css/parser/CSSVariableParser.h"
 
 #include "core/css/CSSCustomPropertyDeclaration.h"
+#include "core/css/CSSVariableReferenceValue.h"
 #include "core/css/parser/CSSParserTokenRange.h"
 
 namespace blink {
 
 bool CSSVariableParser::isValidVariableName(const CSSParserToken& token)
 {
     if (token.type() != IdentToken)
         return false;
 
     StringView value = token.value();
@@ skipping 112 matching lines @@
     bool hasAtApplyRule;
     CSSValueID type = classifyVariableRange(range, hasReferences, hasAtApplyRule);
 
     if (type == CSSValueInvalid)
         return nullptr;
     if (type == CSSValueInternalVariableValue)
         return CSSCustomPropertyDeclaration::create(variableName, CSSVariableData::create(range, hasReferences || hasAtApplyRule));
     return CSSCustomPropertyDeclaration::create(variableName, type);
 }
 
+CSSVariableReferenceValue* CSSVariableParser::parseRegisteredPropertyValue(CSSParserTokenRange range, bool requireVarReference)
+{
+    if (range.atEnd())
+        return nullptr;
+
+    bool hasReferences;
+    bool hasAtApplyRule;
+    CSSValueID type = classifyVariableRange(range, hasReferences, hasAtApplyRule);
+
+    if (type != CSSValueInternalVariableValue)
+        return nullptr; // Invalid or a css-wide keyword
+    if (requireVarReference && !hasReferences)
+        return nullptr;
+    // TODO(timloh): Should this be hasReferences || hasAtApplyRule?
+    return CSSVariableReferenceValue::create(CSSVariableData::create(range, hasReferences));
+}
+
 } // namespace blink