CSS Custom Properties (Variables)

Source/core/css/parser/CSSParserValues.cpp

Index: Source/core/css/parser/CSSParserValues.cpp
diff --git a/Source/core/css/parser/CSSParserValues.cpp b/Source/core/css/parser/CSSParserValues.cpp
index 039e70bc66c8316a9d6b117e5f21abdc72476df7..3392bc709aea306138dc2fa08862c1ca52ac17fa 100644
--- a/Source/core/css/parser/CSSParserValues.cpp
+++ b/Source/core/css/parser/CSSParserValues.cpp
@@ -23,19 +23,48 @@
 
 #include "core/css/CSSFunctionValue.h"
 #include "core/css/CSSSelectorList.h"
+#include "core/css/CSSVariableData.h"
 #include "core/css/parser/CSSParserToken.h"
 #include "core/css/parser/CSSParserTokenRange.h"
 #include "core/css/parser/CSSPropertyParser.h"
+#include "core/css/parser/CSSTokenizer.h"
+#include "core/css/parser/CSSVariableParser.h"
 #include "core/html/parser/HTMLParserIdioms.h"
+#include "wtf/text/StringBuilder.h"
 
 namespace blink {
 
 using namespace WTF;
 
+struct SameSizeAsCSSParserValue {
+    CSSValueID id;
+    CSSParserString valueUnion;
+    int unit;
+};
+
+static_assert(sizeof(CSSParserValue) == sizeof(SameSizeAsCSSParserValue), "CSSParserValue should stay small");
+
 CSSParserValueList::CSSParserValueList(CSSParserTokenRange range, bool& usesRemUnits)
 : m_current(0)
 {
+    init(range, usesRemUnits);
+}
+
+CSSParserValueList::CSSParserValueList(CSSParserTokenRange range, const String& string, bool& usesRemUnits, bool& usesVariables)
+: m_current(0)
+{
+    init(range, usesRemUnits, &usesVariables, &string);
+}
+
+void CSSParserValueList::init(CSSParserTokenRange range, bool& usesRemUnits, bool* usesVariables, const String* string)
+{
+    CSSParserTokenRange originalRangeForVariables = range;
+
     usesRemUnits = false;
+    if (usesVariables) {
+        ASSERT(string);
+        *usesVariables = false;
+    }
     Vector<CSSParserValueList*> stack;
     Vector<int> bracketCounts;
     stack.append(this);
@@ -51,7 +80,8 @@ CSSParserValueList::CSSParserValueList(CSSParserTokenRange range, bool& usesRemU
             if (token.valueEqualsIgnoringCase("url")) {
                 const CSSParserToken& next = range.consumeIncludingWhitespace();
                 if (next.type() == BadStringToken || range.consume().type() != RightParenthesisToken) {
-                    destroyAndClear();
+                    if (usesVariables)
+                        checkForVariableReferencesOrDestroyAndClear(originalRangeForVariables, *string);
                     return;
                 }
                 ASSERT(next.type() == StringToken);
@@ -60,6 +90,10 @@ CSSParserValueList::CSSParserValueList(CSSParserTokenRange range, bool& usesRemU
                 value.unit = CSSPrimitiveValue::CSS_URI;
                 value.string = next.value();
                 break;
+            } else if (token.valueEqualsIgnoringCase("var")) {
+                if (usesVariables)
+                    checkForVariableReferencesOrDestroyAndClear(originalRangeForVariables, *string);
+                return;
             }
 
             CSSParserFunction* function = new CSSParserFunction;
@@ -76,6 +110,8 @@ CSSParserValueList::CSSParserValueList(CSSParserTokenRange range, bool& usesRemU
             stack.append(list);
             bracketCounts.append(0);
             calcDepth += (function->id == CSSValueCalc || function->id == CSSValueWebkitCalc);
+            if (function->id == CSSValueVar && usesVariables)
+                *usesVariables = true;
             continue;
         }
         case LeftParenthesisToken: {
@@ -96,7 +132,8 @@ CSSParserValueList::CSSParserValueList(CSSParserTokenRange range, bool& usesRemU
                 stack.removeLast();
                 bracketCounts.removeLast();
                 if (bracketCounts.isEmpty()) {
-                    destroyAndClear();
+                    if (usesVariables)
+                        checkForVariableReferencesOrDestroyAndClear(originalRangeForVariables, *string);
                     return;
                 }
                 CSSParserValueList* currentList = stack.last();
@@ -181,7 +218,8 @@ CSSParserValueList::CSSParserValueList(CSSParserTokenRange range, bool& usesRemU
             value.setFromOperator(token.delimiter());
             if (calcDepth && token.delimiter() == '+' && (&token - 1)->type() != WhitespaceToken) {
                 // calc(1px+ 2px) is invalid
-                destroyAndClear();
+                if (usesVariables)
+                    checkForVariableReferencesOrDestroyAndClear(originalRangeForVariables, *string);
                 return;
             }
             break;
@@ -245,9 +283,30 @@ static void destroy(Vector<CSSParserValue, 4>& values)
         else if (values[i].unit == CSSParserValue::ValueList
             || values[i].unit == CSSParserValue::DimensionList)
             delete values[i].valueList;
+        else if (values[i].unit == CSSParserValue::VariableValue)
+            values[i].variableData->deref();
     }
 }
 
+void CSSParserValueList::checkForVariableReferencesOrDestroyAndClear(const CSSParserTokenRange& originalRange, const String& string)
+{
+    // We have to clear any state that may have been previously loaded
+    destroyAndClear();
+    if (CSSVariableParser::containsValidVariableReferences(originalRange))
+        consumeVariableValue(originalRange, string);
+}
+
+void CSSParserValueList::consumeVariableValue(const CSSParserTokenRange& originalRange, const String& string)
+{
+    ASSERT(m_values.isEmpty());
+    CSSParserValue variableValue;
+    variableValue.id = CSSValueInternalVariableValue;
+    variableValue.isInt = false;
+    variableValue.unit = CSSParserValue::VariableValue;
+    variableValue.variableData = CSSVariableData::create(originalRange, string).leakRef();
+    addValue(variableValue);
+}
+
 void CSSParserValueList::destroyAndClear()
 {
     destroy(m_values);