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

third_party/WebKit/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 956 matching lines @@
 }
 
 PassRefPtr<StylePath> StyleBuilderConverter::convertPathOrNone(StyleResolverState& state, const CSSValue& value)
 {
     if (value.isPathValue())
         return toCSSPathValue(value).stylePath();
     ASSERT(value.isPrimitiveValue() && toCSSPrimitiveValue(value).getValueID() == CSSValueNone);
     return nullptr;
 }
 
+StyleNavigationValue StyleBuilderConverter::convertStyleNavigationValue(StyleResolverState&, const CSSValue& value)
+{
+    if (!value.isValueList())
+        return ComputedStyle::initialStyleNavigation();
+
+    const CSSValueList& list = toCSSValueList(value);
+    ASSERT(list->length() == 1 || list->length() == 2);

[fs, 2016/05/18 15:55:05]

list.length()

+
+    ASSERT(value.isStringValue());

[fs, 2016/05/18 15:55:05]

|value| will be a CSSValueList here, so you probably mean
list.item(0)->isStringValue() here.

+    String idSelector = toCSSStringValue(list.item(0))->value();
+    if (idSelector.startsWith('#'))

[fs, 2016/05/18 15:55:05]

The CSS parser should be providing a canonical enough representation that this
shouldn't be needed. (I.e either there's either always a '#' or never a '#'.)

+        idSelector.remove(0);
+
+    if (list.length() == 1)
+        return StyleNavigationValue(idSelector);
+
+    if (value.isStringValue())

[fs, 2016/05/18 15:55:05]

Like above, presumably this should be list.item(1)->isStringValue()

+        return StyleNavigationValue(idSelector, toCSSStringValue(list.item(1))->value());
+
+    ASSERT(value.isPrimitiveValue() && (toCSSPrimitiveValue(value).getValueID() == CSSValueRoot || toCSSPrimitiveValue(value).getValueID() == CSSValueCurrent));

[fs, 2016/05/18 15:55:05]

Again, |value| is still the parameter (the list). (Some additional local
variables would probably make sense here.)

+    return StyleNavigationValue(idSelector, toCSSPrimitiveValue(list.item(1))->getValueID() == CSSValueRoot ? Root : Current);
+}
+
 } // namespace blink