[WIP] Implement :dir()

third_party/WebKit/Source/core/html/HTMLElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004-2008, 2013, 2014 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2011 Motorola Mobility. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 693 matching lines @@
 }
 
 bool HTMLElement::hasDirectionAuto() const
 {
     // <bdi> defaults to dir="auto"
     // https://html.spec.whatwg.org/multipage/semantics.html#the-bdi-element
     const AtomicString& direction = fastGetAttribute(dirAttr);
     return (isHTMLBDIElement(*this) && direction == nullAtom) || equalIgnoringCase(direction, "auto");
 }
 
-TextDirection HTMLElement::directionalityIfhasDirAutoAttribute(bool& isAuto) const
-{
-    isAuto = hasDirectionAuto();
-    if (!isAuto)
-        return LTR;
-    return directionality();
-}
-
-TextDirection HTMLElement::directionality(Node** strongDirectionalityTextNode) const
+TextDirection HTMLElement::computeDirectionality(Node** strongDirectionalityTextNode) const
 {
     if (isHTMLInputElement(*this)) {
         HTMLInputElement* inputElement = toHTMLInputElement(const_cast<HTMLElement*>(this));
         bool hasStrongDirectionality;
         TextDirection textDirection = determineDirectionality(inputElement->value(), &hasStrongDirectionality);
         if (strongDirectionalityTextNode)
             *strongDirectionalityTextNode = hasStrongDirectionality ? inputElement : 0;
         return textDirection;
     }
 
@@ skipping 36 matching lines @@
     return layoutObject() && layoutObject()->style() && layoutObject()->style()->selfOrAncestorHasDirAutoAttribute();
 }
 
 void HTMLElement::dirAttributeChanged(const AtomicString& value)
 {
     // If an ancestor has dir=auto, and this node has the first character,
     // changes to dir attribute may affect the ancestor.
     updateDistribution();
     Element* parent = FlatTreeTraversal::parentElement(*this);
     if (parent && parent->isHTMLElement() && toHTMLElement(parent)->selfOrAncestorHasDirAutoAttribute())
-        toHTMLElement(parent)->adjustDirectionalityIfNeededAfterChildAttributeChanged(this);
+        toHTMLElement(parent)->updateSelfOrAncestorForDirAuto();
 
-    if (equalIgnoringCase(value, "auto"))
-        calculateAndAdjustDirectionality();
-}
-
-void HTMLElement::adjustDirectionalityIfNeededAfterChildAttributeChanged(Element* child)
-{
-    ASSERT(selfOrAncestorHasDirAutoAttribute());
-    TextDirection textDirection = directionality();
-    if (layoutObject() && layoutObject()->style() && layoutObject()->style()->direction() != textDirection) {
-        Element* elementToAdjust = this;
-        for (; elementToAdjust; elementToAdjust = FlatTreeTraversal::parentElement(*elementToAdjust)) {
-            if (elementAffectsDirectionality(elementToAdjust)) {
-                elementToAdjust->setNeedsStyleRecalc(LocalStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::WritingModeChange));
-                return;
-            }
-        }
+    if (equalIgnoringCase(value, "auto")) {
+        updateForDirAuto();
+    } else if (elementData() && elementData()->directionality() != CachedTextDirection::NotAutoOrNotCached) {
+        DCHECK(elementData()->isUnique());
+        const_cast<ElementData*>(elementData())->setDirectionality(CachedTextDirection::NotAutoOrNotCached);
     }
 }
 
-void HTMLElement::calculateAndAdjustDirectionality()
+void HTMLElement::updateSelfOrAncestorForDirAuto()
 {
-    TextDirection textDirection = directionality();
-    if (layoutObject() && layoutObject()->style() && layoutObject()->style()->direction() != textDirection)
-        setNeedsStyleRecalc(LocalStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::WritingModeChange));
+    ASSERT(selfOrAncestorHasDirAutoAttribute());
+    //XXX add test that this would code would fail
+    //TextDirection textDirection = computeDirectionality();
+    //if (layoutObject() && layoutObject()->style() && layoutObject()->style()->direction() != textDirection) {
+    Element* elementToAdjust = this;
+    while (!elementAffectsDirectionality(elementToAdjust))
+        elementToAdjust = FlatTreeTraversal::parentElement(*elementToAdjust);
+    toHTMLElement(elementToAdjust)->updateForDirAuto();
+}
+
+void HTMLElement::updateForDirAuto()
+{
+    if (!hasDirectionAuto())
+        return;
+    ensureUniqueElementData().setDirectionality(CachedTextDirection::NotAutoOrNotCached);
+    pseudoStateChanged(CSSSelector::PseudoDir);
+    setNeedsStyleRecalc(LocalStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::WritingModeChange));
+}
+
+void HTMLElement::cacheDirectionalityForDirAuto() const
+{
+    DCHECK(hasDirectionAuto());
+    DCHECK(elementData() && elementData()->isUnique());
+    DCHECK(elementData()->directionality() == CachedTextDirection::NotAutoOrNotCached);
+    if (computeDirectionality() == LTR)
+        elementData()->setDirectionality(CachedTextDirection::AutoLTR);
+    else
+        elementData()->setDirectionality(CachedTextDirection::AutoRTL);
 }
 
 void HTMLElement::adjustDirectionalityIfNeededAfterChildrenChanged(const ChildrenChange& change)
 {
     if (!selfOrAncestorHasDirAutoAttribute())
         return;
 
     updateDistribution();
-
-    for (Element* elementToAdjust = this; elementToAdjust; elementToAdjust = FlatTreeTraversal::parentElement(*elementToAdjust)) {
-        if (elementAffectsDirectionality(elementToAdjust)) {
-            toHTMLElement(elementToAdjust)->calculateAndAdjustDirectionality();
-            return;
-        }
-    }
+    updateSelfOrAncestorForDirAuto();
 }
 
 void HTMLElement::addHTMLLengthToStyle(MutableStylePropertySet* style, CSSPropertyID propertyID, const String& value)
 {
     // FIXME: This function should not spin up the CSS parser, but should instead just figure out the correct
     // length unit and make the appropriate parsed value.
 
     // strip attribute garbage..
     StringImpl* v = value.impl();
     if (v) {
@@ skipping 207 matching lines @@
 #ifndef NDEBUG
 
 // For use in the debugger
 void dumpInnerHTML(blink::HTMLElement*);
 
 void dumpInnerHTML(blink::HTMLElement* element)
 {
     printf("%s\n", element->innerHTML().ascii().data());
 }
 #endif