Implementation of CSS3 nav-up/down/left/right properties from CSS3 UI.

Source/core/css/resolver/StyleBuilderConverter.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
  * copyright notice, this list of conditions and the following disclaimer
  * in the documentation and/or other materials provided with the
  * distribution.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 15 matching lines @@
 
 #include "config.h"
 #include "core/css/resolver/StyleBuilderConverter.h"
 
 #include "core/css/CSSFontFeatureValue.h"
 #include "core/css/CSSFunctionValue.h"
 #include "core/css/CSSGridLineNamesValue.h"
 #include "core/css/CSSPrimitiveValueMappings.h"
 #include "core/css/CSSReflectValue.h"
 #include "core/css/CSSShadowValue.h"
+#include "core/css/CSSValuePool.h"

[fs, 2014/10/01 10:52:14]

This include looks odd here - I don't see anything that needs/uses the value
pool?

 #include "core/css/Pair.h"
 #include "core/css/Rect.h"
 #include "core/svg/SVGURIReference.h"
 
 namespace blink {
 
 namespace {
 
 static GridLength convertGridTrackBreadth(const StyleResolverState& state, CSSPrimitiveValue* primitiveValue)
 {
@@ skipping 558 matching lines @@
         return primitiveValue->getRGBA32Value();
     ASSERT(primitiveValue->getValueID() == CSSValueCurrentcolor);
     return state.style()->color();
 }
 
 PassRefPtr<SVGLength> StyleBuilderConverter::convertSVGLength(StyleResolverState&, CSSValue* value)
 {
     return SVGLength::fromCSSPrimitiveValue(toCSSPrimitiveValue(value));
 }
 
+StyleNavigationValue StyleBuilderConverter::convertStyleNavigationValue(StyleResolverState&, CSSValue* value)
+{
+    if (!value->isValueList())

[Timothy Loh, 2014/10/01 13:14:54]

I like asserting that the value is what we expect (auto) in these cases.

+        return RenderStyle::initialStyleNavigation();
+
+    CSSValueList* valueList = toCSSValueList(value);
+    ASSERT(valueList->length() == 1 || valueList->length() == 2);

[Timothy Loh, 2014/10/01 13:14:54]

When is the length ever 1?

+
+    String idSelector = toCSSPrimitiveValue(valueList->item(0))->getStringValue();
+    if (idSelector.startsWith('#'))
+        idSelector.remove(0);
+
+    if (valueList->length() == 1)
+        return StyleNavigationValue(idSelector);

[Timothy Loh, 2014/10/01 13:14:54]

As above; this seems unreachable to me.

+
+    CSSPrimitiveValue* targetValue = toCSSPrimitiveValue(valueList->item(1));
+    if (targetValue->isString())
+        return StyleNavigationValue(idSelector, targetValue->getStringValue());
+
+    const CSSValueID targetValueID = targetValue->getValueID();
+    return StyleNavigationValue(idSelector, targetValueID == CSSValueRoot ? Root : Current);
+}
+
 float StyleBuilderConverter::convertTextStrokeWidth(StyleResolverState& state, CSSValue* value)
 {
     CSSPrimitiveValue* primitiveValue = toCSSPrimitiveValue(value);
     if (primitiveValue->getValueID()) {
         float multiplier = convertLineWidth<float>(state, value);
         return CSSPrimitiveValue::create(multiplier / 48, CSSPrimitiveValue::CSS_EMS)->computeLength<float>(state.cssToLengthConversionData());
     }
     return primitiveValue->computeLength<float>(state.cssToLengthConversionData());
 }
 
 } // namespace blink