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      1 /*
      2  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
      3  * Copyright (C) 2008, 2009, 2010, 2011 Google Inc. All rights reserved.
      4  * Copyright (C) 2011 Igalia S.L.
      5  * Copyright (C) 2011 Motorola Mobility. All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
     17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
     20  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     21  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     22  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     23  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
     24  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     27  */
     28 
     29 #include "config.h"
     30 #include "core/editing/markup.h"
     31 
     32 #include "bindings/core/v8/ExceptionState.h"
     33 #include "core/CSSPropertyNames.h"
     34 #include "core/CSSValueKeywords.h"
     35 #include "core/HTMLNames.h"
     36 #include "core/css/CSSPrimitiveValue.h"
     37 #include "core/css/CSSValue.h"
     38 #include "core/css/StylePropertySet.h"
     39 #include "core/dom/CDATASection.h"
     40 #include "core/dom/ChildListMutationScope.h"
     41 #include "core/dom/Comment.h"
     42 #include "core/dom/ContextFeatures.h"
     43 #include "core/dom/DocumentFragment.h"
     44 #include "core/dom/ElementTraversal.h"
     45 #include "core/dom/ExceptionCode.h"
     46 #include "core/dom/NodeTraversal.h"
     47 #include "core/dom/Range.h"
     48 #include "core/editing/Editor.h"
     49 #include "core/editing/MarkupAccumulator.h"
     50 #include "core/editing/TextIterator.h"
     51 #include "core/editing/VisibleSelection.h"
     52 #include "core/editing/VisibleUnits.h"
     53 #include "core/editing/htmlediting.h"
     54 #include "core/frame/LocalFrame.h"
     55 #include "core/html/HTMLAnchorElement.h"
     56 #include "core/html/HTMLBRElement.h"
     57 #include "core/html/HTMLBodyElement.h"
     58 #include "core/html/HTMLDivElement.h"
     59 #include "core/html/HTMLElement.h"
     60 #include "core/html/HTMLQuoteElement.h"
     61 #include "core/html/HTMLSpanElement.h"
     62 #include "core/html/HTMLTableCellElement.h"
     63 #include "core/html/HTMLTableElement.h"
     64 #include "core/html/HTMLTextFormControlElement.h"
     65 #include "core/rendering/RenderObject.h"
     66 #include "platform/weborigin/KURL.h"
     67 #include "wtf/StdLibExtras.h"
     68 #include "wtf/text/StringBuilder.h"
     69 
     70 namespace blink {
     71 
     72 using namespace HTMLNames;
     73 
     74 static bool propertyMissingOrEqualToNone(StylePropertySet*, CSSPropertyID);
     75 
     76 class AttributeChange {
     77     ALLOW_ONLY_INLINE_ALLOCATION();
     78 public:
     79     AttributeChange()
     80         : m_name(nullAtom, nullAtom, nullAtom)
     81     {
     82     }
     83 
     84     AttributeChange(PassRefPtrWillBeRawPtr<Element> element, const QualifiedName& name, const String& value)
     85         : m_element(element), m_name(name), m_value(value)
     86     {
     87     }
     88 
     89     void apply()
     90     {
     91         m_element->setAttribute(m_name, AtomicString(m_value));
     92     }
     93 
     94     void trace(Visitor* visitor)
     95     {
     96         visitor->trace(m_element);
     97     }
     98 
     99 private:
    100     RefPtrWillBeMember<Element> m_element;
    101     QualifiedName m_name;
    102     String m_value;
    103 };
    104 
    105 } // namespace blink
    106 
    107 WTF_ALLOW_INIT_WITH_MEM_FUNCTIONS(blink::AttributeChange);
    108 
    109 namespace blink {
    110 
    111 static void completeURLs(DocumentFragment& fragment, const String& baseURL)
    112 {
    113     WillBeHeapVector<AttributeChange> changes;
    114 
    115     KURL parsedBaseURL(ParsedURLString, baseURL);
    116 
    117     for (Element* element = ElementTraversal::firstWithin(fragment); element; element = ElementTraversal::next(*element, &fragment)) {
    118         AttributeCollection attributes = element->attributes();
    119         AttributeCollection::iterator end = attributes.end();
    120         for (AttributeCollection::iterator it = attributes.begin(); it != end; ++it) {
    121             if (element->isURLAttribute(*it) && !it->value().isEmpty())
    122                 changes.append(AttributeChange(element, it->name(), KURL(parsedBaseURL, it->value()).string()));
    123         }
    124     }
    125 
    126     size_t numChanges = changes.size();
    127     for (size_t i = 0; i < numChanges; ++i)
    128         changes[i].apply();
    129 }
    130 
    131 class StyledMarkupAccumulator FINAL : public MarkupAccumulator {
    132 public:
    133     enum RangeFullySelectsNode { DoesFullySelectNode, DoesNotFullySelectNode };
    134 
    135     StyledMarkupAccumulator(WillBeHeapVector<RawPtrWillBeMember<Node> >* nodes, EAbsoluteURLs, EAnnotateForInterchange, RawPtr<const Range>, Node* highestNodeToBeSerialized = 0);
    136     Node* serializeNodes(Node* startNode, Node* pastEnd);
    137     void appendString(const String& s) { return MarkupAccumulator::appendString(s); }
    138     void wrapWithNode(ContainerNode&, bool convertBlocksToInlines = false, RangeFullySelectsNode = DoesFullySelectNode);
    139     void wrapWithStyleNode(StylePropertySet*, const Document&, bool isBlock = false);
    140     String takeResults();
    141 
    142 private:
    143     void appendStyleNodeOpenTag(StringBuilder&, StylePropertySet*, const Document&, bool isBlock = false);
    144     const String& styleNodeCloseTag(bool isBlock = false);
    145     virtual void appendText(StringBuilder& out, Text&) OVERRIDE;
    146     String renderedText(Node&, const Range*);
    147     String stringValueForRange(const Node&, const Range*);
    148     void appendElement(StringBuilder& out, Element&, bool addDisplayInline, RangeFullySelectsNode);
    149     virtual void appendElement(StringBuilder& out, Element& element, Namespaces*) OVERRIDE { appendElement(out, element, false, DoesFullySelectNode); }
    150 
    151     enum NodeTraversalMode { EmitString, DoNotEmitString };
    152     Node* traverseNodesForSerialization(Node* startNode, Node* pastEnd, NodeTraversalMode);
    153 
    154     bool shouldAnnotate() const { return m_shouldAnnotate == AnnotateForInterchange || m_shouldAnnotate == AnnotateForNavigationTransition; }
    155     bool shouldApplyWrappingStyle(const Node& node) const
    156     {
    157         return m_highestNodeToBeSerialized && m_highestNodeToBeSerialized->parentNode() == node.parentNode()
    158             && m_wrappingStyle && m_wrappingStyle->style();
    159     }
    160 
    161     Vector<String> m_reversedPrecedingMarkup;
    162     const EAnnotateForInterchange m_shouldAnnotate;
    163     RawPtrWillBeMember<Node> m_highestNodeToBeSerialized;
    164     RefPtrWillBeMember<EditingStyle> m_wrappingStyle;
    165 };
    166 
    167 inline StyledMarkupAccumulator::StyledMarkupAccumulator(WillBeHeapVector<RawPtrWillBeMember<Node> >* nodes, EAbsoluteURLs shouldResolveURLs, EAnnotateForInterchange shouldAnnotate, RawPtr<const Range> range, Node* highestNodeToBeSerialized)
    168     : MarkupAccumulator(nodes, shouldResolveURLs, range)
    169     , m_shouldAnnotate(shouldAnnotate)
    170     , m_highestNodeToBeSerialized(highestNodeToBeSerialized)
    171 {
    172 }
    173 
    174 void StyledMarkupAccumulator::wrapWithNode(ContainerNode& node, bool convertBlocksToInlines, RangeFullySelectsNode rangeFullySelectsNode)
    175 {
    176     StringBuilder markup;
    177     if (node.isElementNode())
    178         appendElement(markup, toElement(node), convertBlocksToInlines && isBlock(&node), rangeFullySelectsNode);
    179     else
    180         appendStartMarkup(markup, node, 0);
    181     m_reversedPrecedingMarkup.append(markup.toString());
    182     if (node.isElementNode())
    183         appendEndTag(toElement(node));
    184     if (m_nodes)
    185         m_nodes->append(&node);
    186 }
    187 
    188 void StyledMarkupAccumulator::wrapWithStyleNode(StylePropertySet* style, const Document& document, bool isBlock)
    189 {
    190     StringBuilder openTag;
    191     appendStyleNodeOpenTag(openTag, style, document, isBlock);
    192     m_reversedPrecedingMarkup.append(openTag.toString());
    193     appendString(styleNodeCloseTag(isBlock));
    194 }
    195 
    196 void StyledMarkupAccumulator::appendStyleNodeOpenTag(StringBuilder& out, StylePropertySet* style, const Document& document, bool isBlock)
    197 {
    198     // wrappingStyleForSerialization should have removed -webkit-text-decorations-in-effect
    199     ASSERT(propertyMissingOrEqualToNone(style, CSSPropertyWebkitTextDecorationsInEffect));
    200     if (isBlock)
    201         out.appendLiteral("<div style=\"");
    202     else
    203         out.appendLiteral("<span style=\"");
    204     appendAttributeValue(out, style->asText(), document.isHTMLDocument());
    205     out.appendLiteral("\">");
    206 }
    207 
    208 const String& StyledMarkupAccumulator::styleNodeCloseTag(bool isBlock)
    209 {
    210     DEFINE_STATIC_LOCAL(const String, divClose, ("</div>"));
    211     DEFINE_STATIC_LOCAL(const String, styleSpanClose, ("</span>"));
    212     return isBlock ? divClose : styleSpanClose;
    213 }
    214 
    215 String StyledMarkupAccumulator::takeResults()
    216 {
    217     StringBuilder result;
    218     result.reserveCapacity(totalLength(m_reversedPrecedingMarkup) + length());
    219 
    220     for (size_t i = m_reversedPrecedingMarkup.size(); i > 0; --i)
    221         result.append(m_reversedPrecedingMarkup[i - 1]);
    222 
    223     concatenateMarkup(result);
    224 
    225     // We remove '\0' characters because they are not visibly rendered to the user.
    226     return result.toString().replace(0, "");
    227 }
    228 
    229 void StyledMarkupAccumulator::appendText(StringBuilder& out, Text& text)
    230 {
    231     const bool parentIsTextarea = text.parentElement() && text.parentElement()->tagQName() == textareaTag;
    232     const bool wrappingSpan = shouldApplyWrappingStyle(text) && !parentIsTextarea;
    233     if (wrappingSpan) {
    234         RefPtrWillBeRawPtr<EditingStyle> wrappingStyle = m_wrappingStyle->copy();
    235         // FIXME: <rdar://problem/5371536> Style rules that match pasted content can change it's appearance
    236         // Make sure spans are inline style in paste side e.g. span { display: block }.
    237         wrappingStyle->forceInline();
    238         // FIXME: Should this be included in forceInline?
    239         wrappingStyle->style()->setProperty(CSSPropertyFloat, CSSValueNone);
    240 
    241         appendStyleNodeOpenTag(out, wrappingStyle->style(), text.document());
    242     }
    243 
    244     if (!shouldAnnotate() || parentIsTextarea)
    245         MarkupAccumulator::appendText(out, text);
    246     else {
    247         const bool useRenderedText = !enclosingElementWithTag(firstPositionInNode(&text), selectTag);
    248         String content = useRenderedText ? renderedText(text, m_range) : stringValueForRange(text, m_range);
    249         StringBuilder buffer;
    250         appendCharactersReplacingEntities(buffer, content, 0, content.length(), EntityMaskInPCDATA);
    251         out.append(convertHTMLTextToInterchangeFormat(buffer.toString(), text));
    252     }
    253 
    254     if (wrappingSpan)
    255         out.append(styleNodeCloseTag());
    256 }
    257 
    258 String StyledMarkupAccumulator::renderedText(Node& node, const Range* range)
    259 {
    260     if (!node.isTextNode())
    261         return String();
    262 
    263     Text& textNode = toText(node);
    264     unsigned startOffset = 0;
    265     unsigned endOffset = textNode.length();
    266 
    267     if (range && textNode == range->startContainer())
    268         startOffset = range->startOffset();
    269     if (range && textNode == range->endContainer())
    270         endOffset = range->endOffset();
    271 
    272     Position start = createLegacyEditingPosition(&textNode, startOffset);
    273     Position end = createLegacyEditingPosition(&textNode, endOffset);
    274     return plainText(Range::create(textNode.document(), start, end).get());
    275 }
    276 
    277 String StyledMarkupAccumulator::stringValueForRange(const Node& node, const Range* range)
    278 {
    279     if (!range)
    280         return node.nodeValue();
    281 
    282     String str = node.nodeValue();
    283     if (node == range->endContainer())
    284         str.truncate(range->endOffset());
    285     if (node == range->startContainer())
    286         str.remove(0, range->startOffset());
    287     return str;
    288 }
    289 
    290 void StyledMarkupAccumulator::appendElement(StringBuilder& out, Element& element, bool addDisplayInline, RangeFullySelectsNode rangeFullySelectsNode)
    291 {
    292     const bool documentIsHTML = element.document().isHTMLDocument();
    293     appendOpenTag(out, element, 0);
    294 
    295     const bool shouldAnnotateOrForceInline = element.isHTMLElement() && (shouldAnnotate() || addDisplayInline);
    296     const bool shouldOverrideStyleAttr = shouldAnnotateOrForceInline || shouldApplyWrappingStyle(element);
    297 
    298     AttributeCollection attributes = element.attributes();
    299     AttributeCollection::iterator end = attributes.end();
    300     for (AttributeCollection::iterator it = attributes.begin(); it != end; ++it) {
    301         // We'll handle the style attribute separately, below.
    302         if (it->name() == styleAttr && shouldOverrideStyleAttr)
    303             continue;
    304         appendAttribute(out, element, *it, 0);
    305     }
    306 
    307     if (shouldOverrideStyleAttr) {
    308         RefPtrWillBeRawPtr<EditingStyle> newInlineStyle = nullptr;
    309 
    310         if (shouldApplyWrappingStyle(element)) {
    311             newInlineStyle = m_wrappingStyle->copy();
    312             newInlineStyle->removePropertiesInElementDefaultStyle(&element);
    313             newInlineStyle->removeStyleConflictingWithStyleOfElement(&element);
    314         } else
    315             newInlineStyle = EditingStyle::create();
    316 
    317         if (element.isStyledElement() && element.inlineStyle())
    318             newInlineStyle->overrideWithStyle(element.inlineStyle());
    319 
    320         if (shouldAnnotateOrForceInline) {
    321             if (shouldAnnotate())
    322                 newInlineStyle->mergeStyleFromRulesForSerialization(&toHTMLElement(element));
    323 
    324             if (&element == m_highestNodeToBeSerialized && m_shouldAnnotate == AnnotateForNavigationTransition)
    325                 newInlineStyle->addAbsolutePositioningFromElement(element);
    326 
    327             if (addDisplayInline)
    328                 newInlineStyle->forceInline();
    329 
    330             // If the node is not fully selected by the range, then we don't want to keep styles that affect its relationship to the nodes around it
    331             // only the ones that affect it and the nodes within it.
    332             if (rangeFullySelectsNode == DoesNotFullySelectNode && newInlineStyle->style())
    333                 newInlineStyle->style()->removeProperty(CSSPropertyFloat);
    334         }
    335 
    336         if (!newInlineStyle->isEmpty()) {
    337             out.appendLiteral(" style=\"");
    338             appendAttributeValue(out, newInlineStyle->style()->asText(), documentIsHTML);
    339             out.append('\"');
    340         }
    341     }
    342 
    343     appendCloseTag(out, element);
    344 }
    345 
    346 Node* StyledMarkupAccumulator::serializeNodes(Node* startNode, Node* pastEnd)
    347 {
    348     if (!m_highestNodeToBeSerialized) {
    349         Node* lastClosed = traverseNodesForSerialization(startNode, pastEnd, DoNotEmitString);
    350         m_highestNodeToBeSerialized = lastClosed;
    351     }
    352 
    353     if (m_highestNodeToBeSerialized && m_highestNodeToBeSerialized->parentNode()) {
    354         m_wrappingStyle = EditingStyle::wrappingStyleForSerialization(m_highestNodeToBeSerialized->parentNode(), shouldAnnotate());
    355         if (m_shouldAnnotate == AnnotateForNavigationTransition) {
    356             m_wrappingStyle->style()->removeProperty(CSSPropertyBackgroundColor);
    357             m_wrappingStyle->style()->removeProperty(CSSPropertyBackgroundImage);
    358         }
    359     }
    360 
    361 
    362     return traverseNodesForSerialization(startNode, pastEnd, EmitString);
    363 }
    364 
    365 Node* StyledMarkupAccumulator::traverseNodesForSerialization(Node* startNode, Node* pastEnd, NodeTraversalMode traversalMode)
    366 {
    367     const bool shouldEmit = traversalMode == EmitString;
    368     WillBeHeapVector<RawPtrWillBeMember<ContainerNode> > ancestorsToClose;
    369     Node* next;
    370     Node* lastClosed = 0;
    371     for (Node* n = startNode; n != pastEnd; n = next) {
    372         // According to <rdar://problem/5730668>, it is possible for n to blow
    373         // past pastEnd and become null here. This shouldn't be possible.
    374         // This null check will prevent crashes (but create too much markup)
    375         // and the ASSERT will hopefully lead us to understanding the problem.
    376         ASSERT(n);
    377         if (!n)
    378             break;
    379 
    380         next = NodeTraversal::next(*n);
    381         bool openedTag = false;
    382 
    383         if (isBlock(n) && canHaveChildrenForEditing(n) && next == pastEnd)
    384             // Don't write out empty block containers that aren't fully selected.
    385             continue;
    386 
    387         if (!n->renderer() && !enclosingElementWithTag(firstPositionInOrBeforeNode(n), selectTag) && m_shouldAnnotate != AnnotateForNavigationTransition) {
    388             next = NodeTraversal::nextSkippingChildren(*n);
    389             // Don't skip over pastEnd.
    390             if (pastEnd && pastEnd->isDescendantOf(n))
    391                 next = pastEnd;
    392         } else {
    393             // Add the node to the markup if we're not skipping the descendants
    394             if (shouldEmit)
    395                 appendStartTag(*n);
    396 
    397             // If node has no children, close the tag now.
    398             if (n->isContainerNode() && toContainerNode(n)->hasChildren()) {
    399                 openedTag = true;
    400                 ancestorsToClose.append(toContainerNode(n));
    401             } else {
    402                 if (shouldEmit && n->isElementNode())
    403                     appendEndTag(toElement(*n));
    404                 lastClosed = n;
    405             }
    406         }
    407 
    408         // If we didn't insert open tag and there's no more siblings or we're at the end of the traversal, take care of ancestors.
    409         // FIXME: What happens if we just inserted open tag and reached the end?
    410         if (!openedTag && (!n->nextSibling() || next == pastEnd)) {
    411             // Close up the ancestors.
    412             while (!ancestorsToClose.isEmpty()) {
    413                 ContainerNode* ancestor = ancestorsToClose.last();
    414                 ASSERT(ancestor);
    415                 if (next != pastEnd && next->isDescendantOf(ancestor))
    416                     break;
    417                 // Not at the end of the range, close ancestors up to sibling of next node.
    418                 if (shouldEmit && ancestor->isElementNode())
    419                     appendEndTag(toElement(*ancestor));
    420                 lastClosed = ancestor;
    421                 ancestorsToClose.removeLast();
    422             }
    423 
    424             // Surround the currently accumulated markup with markup for ancestors we never opened as we leave the subtree(s) rooted at those ancestors.
    425             ContainerNode* nextParent = next ? next->parentNode() : 0;
    426             if (next != pastEnd && n != nextParent) {
    427                 Node* lastAncestorClosedOrSelf = n->isDescendantOf(lastClosed) ? lastClosed : n;
    428                 for (ContainerNode* parent = lastAncestorClosedOrSelf->parentNode(); parent && parent != nextParent; parent = parent->parentNode()) {
    429                     // All ancestors that aren't in the ancestorsToClose list should either be a) unrendered:
    430                     if (!parent->renderer())
    431                         continue;
    432                     // or b) ancestors that we never encountered during a pre-order traversal starting at startNode:
    433                     ASSERT(startNode->isDescendantOf(parent));
    434                     if (shouldEmit)
    435                         wrapWithNode(*parent);
    436                     lastClosed = parent;
    437                 }
    438             }
    439         }
    440     }
    441 
    442     return lastClosed;
    443 }
    444 
    445 static bool isHTMLBlockElement(const Node* node)
    446 {
    447     ASSERT(node);
    448     return isHTMLTableCellElement(*node)
    449         || isNonTableCellHTMLBlockElement(node);
    450 }
    451 
    452 static HTMLElement* ancestorToRetainStructureAndAppearanceForBlock(Element* commonAncestorBlock)
    453 {
    454     if (!commonAncestorBlock)
    455         return 0;
    456 
    457     if (commonAncestorBlock->hasTagName(tbodyTag) || isHTMLTableRowElement(*commonAncestorBlock))
    458         return Traversal<HTMLTableElement>::firstAncestor(*commonAncestorBlock);
    459 
    460     if (isNonTableCellHTMLBlockElement(commonAncestorBlock))
    461         return toHTMLElement(commonAncestorBlock);
    462 
    463     return 0;
    464 }
    465 
    466 static inline HTMLElement* ancestorToRetainStructureAndAppearance(Node* commonAncestor)
    467 {
    468     return ancestorToRetainStructureAndAppearanceForBlock(enclosingBlock(commonAncestor));
    469 }
    470 
    471 static inline HTMLElement* ancestorToRetainStructureAndAppearanceWithNoRenderer(Node* commonAncestor)
    472 {
    473     HTMLElement* commonAncestorBlock = toHTMLElement(enclosingNodeOfType(firstPositionInOrBeforeNode(commonAncestor), isHTMLBlockElement));
    474     return ancestorToRetainStructureAndAppearanceForBlock(commonAncestorBlock);
    475 }
    476 
    477 static bool propertyMissingOrEqualToNone(StylePropertySet* style, CSSPropertyID propertyID)
    478 {
    479     if (!style)
    480         return false;
    481     RefPtrWillBeRawPtr<CSSValue> value = style->getPropertyCSSValue(propertyID);
    482     if (!value)
    483         return true;
    484     if (!value->isPrimitiveValue())
    485         return false;
    486     return toCSSPrimitiveValue(value.get())->getValueID() == CSSValueNone;
    487 }
    488 
    489 static bool needInterchangeNewlineAfter(const VisiblePosition& v)
    490 {
    491     VisiblePosition next = v.next();
    492     Node* upstreamNode = next.deepEquivalent().upstream().deprecatedNode();
    493     Node* downstreamNode = v.deepEquivalent().downstream().deprecatedNode();
    494     // Add an interchange newline if a paragraph break is selected and a br won't already be added to the markup to represent it.
    495     return isEndOfParagraph(v) && isStartOfParagraph(next) && !(isHTMLBRElement(*upstreamNode) && upstreamNode == downstreamNode);
    496 }
    497 
    498 static PassRefPtrWillBeRawPtr<EditingStyle> styleFromMatchedRulesAndInlineDecl(const HTMLElement* element)
    499 {
    500     RefPtrWillBeRawPtr<EditingStyle> style = EditingStyle::create(element->inlineStyle());
    501     // FIXME: Having to const_cast here is ugly, but it is quite a bit of work to untangle
    502     // the non-const-ness of styleFromMatchedRulesForElement.
    503     style->mergeStyleFromRules(const_cast<HTMLElement*>(element));
    504     return style.release();
    505 }
    506 
    507 static bool isPresentationalHTMLElement(const Node* node)
    508 {
    509     if (!node->isHTMLElement())
    510         return false;
    511 
    512     const HTMLElement& element = toHTMLElement(*node);
    513     return element.hasTagName(uTag) || element.hasTagName(sTag) || element.hasTagName(strikeTag)
    514         || element.hasTagName(iTag) || element.hasTagName(emTag) || element.hasTagName(bTag) || element.hasTagName(strongTag);
    515 }
    516 
    517 static HTMLElement* highestAncestorToWrapMarkup(const Range* range, EAnnotateForInterchange shouldAnnotate, Node* constrainingAncestor)
    518 {
    519     Node* commonAncestor = range->commonAncestorContainer();
    520     ASSERT(commonAncestor);
    521     HTMLElement* specialCommonAncestor = 0;
    522     if (shouldAnnotate == AnnotateForInterchange) {
    523         // Include ancestors that aren't completely inside the range but are required to retain
    524         // the structure and appearance of the copied markup.
    525         specialCommonAncestor = ancestorToRetainStructureAndAppearance(commonAncestor);
    526 
    527         if (Node* parentListNode = enclosingNodeOfType(firstPositionInOrBeforeNode(range->firstNode()), isListItem)) {
    528             if (blink::areRangesEqual(VisibleSelection::selectionFromContentsOfNode(parentListNode).toNormalizedRange().get(), range)) {
    529                 ContainerNode* ancestor = parentListNode->parentNode();
    530                 while (ancestor && !isHTMLListElement(ancestor))
    531                     ancestor = ancestor->parentNode();
    532                 specialCommonAncestor = toHTMLElement(ancestor);
    533             }
    534         }
    535 
    536         // Retain the Mail quote level by including all ancestor mail block quotes.
    537         if (HTMLQuoteElement* highestMailBlockquote = toHTMLQuoteElement(highestEnclosingNodeOfType(firstPositionInOrBeforeNode(range->firstNode()), isMailHTMLBlockquoteElement, CanCrossEditingBoundary)))
    538             specialCommonAncestor = highestMailBlockquote;
    539     }
    540 
    541     Node* checkAncestor = specialCommonAncestor ? specialCommonAncestor : commonAncestor;
    542     if (checkAncestor->renderer()) {
    543         HTMLElement* newSpecialCommonAncestor = toHTMLElement(highestEnclosingNodeOfType(firstPositionInNode(checkAncestor), &isPresentationalHTMLElement, CanCrossEditingBoundary, constrainingAncestor));
    544         if (newSpecialCommonAncestor)
    545             specialCommonAncestor = newSpecialCommonAncestor;
    546     }
    547 
    548     // If a single tab is selected, commonAncestor will be a text node inside a tab span.
    549     // If two or more tabs are selected, commonAncestor will be the tab span.
    550     // In either case, if there is a specialCommonAncestor already, it will necessarily be above
    551     // any tab span that needs to be included.
    552     if (!specialCommonAncestor && isTabHTMLSpanElementTextNode(commonAncestor))
    553         specialCommonAncestor = toHTMLSpanElement(commonAncestor->parentNode());
    554     if (!specialCommonAncestor && isTabHTMLSpanElement(commonAncestor))
    555         specialCommonAncestor = toHTMLSpanElement(commonAncestor);
    556 
    557     if (HTMLAnchorElement* enclosingAnchor = toHTMLAnchorElement(enclosingElementWithTag(firstPositionInNode(specialCommonAncestor ? specialCommonAncestor : commonAncestor), aTag)))
    558         specialCommonAncestor = enclosingAnchor;
    559 
    560     return specialCommonAncestor;
    561 }
    562 
    563 // FIXME: Shouldn't we omit style info when annotate == DoNotAnnotateForInterchange?
    564 // FIXME: At least, annotation and style info should probably not be included in range.markupString()
    565 static String createMarkupInternal(Document& document, const Range* range, const Range* updatedRange, WillBeHeapVector<RawPtrWillBeMember<Node> >* nodes,
    566     EAnnotateForInterchange shouldAnnotate, bool convertBlocksToInlines, EAbsoluteURLs shouldResolveURLs, Node* constrainingAncestor)
    567 {
    568     ASSERT(range);
    569     ASSERT(updatedRange);
    570     DEFINE_STATIC_LOCAL(const String, interchangeNewlineString, ("<br class=\"" AppleInterchangeNewline "\">"));
    571 
    572     bool collapsed = updatedRange->collapsed();
    573     if (collapsed)
    574         return emptyString();
    575     Node* commonAncestor = updatedRange->commonAncestorContainer();
    576     if (!commonAncestor)
    577         return emptyString();
    578 
    579     document.updateLayoutIgnorePendingStylesheets();
    580 
    581     HTMLBodyElement* body = toHTMLBodyElement(enclosingElementWithTag(firstPositionInNode(commonAncestor), bodyTag));
    582     HTMLBodyElement* fullySelectedRoot = 0;
    583     // FIXME: Do this for all fully selected blocks, not just the body.
    584     if (body && areRangesEqual(VisibleSelection::selectionFromContentsOfNode(body).toNormalizedRange().get(), range))
    585         fullySelectedRoot = body;
    586     HTMLElement* specialCommonAncestor = highestAncestorToWrapMarkup(updatedRange, shouldAnnotate, constrainingAncestor);
    587     StyledMarkupAccumulator accumulator(nodes, shouldResolveURLs, shouldAnnotate, updatedRange, specialCommonAncestor);
    588     Node* pastEnd = updatedRange->pastLastNode();
    589 
    590     Node* startNode = updatedRange->firstNode();
    591     VisiblePosition visibleStart(updatedRange->startPosition(), VP_DEFAULT_AFFINITY);
    592     VisiblePosition visibleEnd(updatedRange->endPosition(), VP_DEFAULT_AFFINITY);
    593     if (shouldAnnotate == AnnotateForInterchange && needInterchangeNewlineAfter(visibleStart)) {
    594         if (visibleStart == visibleEnd.previous())
    595             return interchangeNewlineString;
    596 
    597         accumulator.appendString(interchangeNewlineString);
    598         startNode = visibleStart.next().deepEquivalent().deprecatedNode();
    599 
    600         if (pastEnd && Range::compareBoundaryPoints(startNode, 0, pastEnd, 0, ASSERT_NO_EXCEPTION) >= 0)
    601             return interchangeNewlineString;
    602     }
    603 
    604     Node* lastClosed = accumulator.serializeNodes(startNode, pastEnd);
    605 
    606     if (specialCommonAncestor && lastClosed) {
    607         // Also include all of the ancestors of lastClosed up to this special ancestor.
    608         for (ContainerNode* ancestor = lastClosed->parentNode(); ancestor; ancestor = ancestor->parentNode()) {
    609             if (ancestor == fullySelectedRoot && !convertBlocksToInlines) {
    610                 RefPtrWillBeRawPtr<EditingStyle> fullySelectedRootStyle = styleFromMatchedRulesAndInlineDecl(fullySelectedRoot);
    611 
    612                 // Bring the background attribute over, but not as an attribute because a background attribute on a div
    613                 // appears to have no effect.
    614                 if ((!fullySelectedRootStyle || !fullySelectedRootStyle->style() || !fullySelectedRootStyle->style()->getPropertyCSSValue(CSSPropertyBackgroundImage))
    615                     && fullySelectedRoot->hasAttribute(backgroundAttr))
    616                     fullySelectedRootStyle->style()->setProperty(CSSPropertyBackgroundImage, "url('" + fullySelectedRoot->getAttribute(backgroundAttr) + "')");
    617 
    618                 if (fullySelectedRootStyle->style()) {
    619                     // Reset the CSS properties to avoid an assertion error in addStyleMarkup().
    620                     // This assertion is caused at least when we select all text of a <body> element whose
    621                     // 'text-decoration' property is "inherit", and copy it.
    622                     if (!propertyMissingOrEqualToNone(fullySelectedRootStyle->style(), CSSPropertyTextDecoration))
    623                         fullySelectedRootStyle->style()->setProperty(CSSPropertyTextDecoration, CSSValueNone);
    624                     if (!propertyMissingOrEqualToNone(fullySelectedRootStyle->style(), CSSPropertyWebkitTextDecorationsInEffect))
    625                         fullySelectedRootStyle->style()->setProperty(CSSPropertyWebkitTextDecorationsInEffect, CSSValueNone);
    626                     accumulator.wrapWithStyleNode(fullySelectedRootStyle->style(), document, true);
    627                 }
    628             } else {
    629                 // Since this node and all the other ancestors are not in the selection we want to set RangeFullySelectsNode to DoesNotFullySelectNode
    630                 // so that styles that affect the exterior of the node are not included.
    631                 accumulator.wrapWithNode(*ancestor, convertBlocksToInlines, StyledMarkupAccumulator::DoesNotFullySelectNode);
    632             }
    633             if (nodes)
    634                 nodes->append(ancestor);
    635 
    636             if (ancestor == specialCommonAncestor)
    637                 break;
    638         }
    639     }
    640 
    641     // FIXME: The interchange newline should be placed in the block that it's in, not after all of the content, unconditionally.
    642     if (shouldAnnotate == AnnotateForInterchange && needInterchangeNewlineAfter(visibleEnd.previous()))
    643         accumulator.appendString(interchangeNewlineString);
    644 
    645     return accumulator.takeResults();
    646 }
    647 
    648 String createMarkup(const Range* range, WillBeHeapVector<RawPtrWillBeMember<Node> >* nodes, EAnnotateForInterchange shouldAnnotate, bool convertBlocksToInlines, EAbsoluteURLs shouldResolveURLs, Node* constrainingAncestor)
    649 {
    650     if (!range)
    651         return emptyString();
    652 
    653     Document& document = range->ownerDocument();
    654     const Range* updatedRange = range;
    655 
    656     return createMarkupInternal(document, range, updatedRange, nodes, shouldAnnotate, convertBlocksToInlines, shouldResolveURLs, constrainingAncestor);
    657 }
    658 
    659 PassRefPtrWillBeRawPtr<DocumentFragment> createFragmentFromMarkup(Document& document, const String& markup, const String& baseURL, ParserContentPolicy parserContentPolicy)
    660 {
    661     // We use a fake body element here to trick the HTML parser to using the InBody insertion mode.
    662     RefPtrWillBeRawPtr<HTMLBodyElement> fakeBody = HTMLBodyElement::create(document);
    663     RefPtrWillBeRawPtr<DocumentFragment> fragment = DocumentFragment::create(document);
    664 
    665     fragment->parseHTML(markup, fakeBody.get(), parserContentPolicy);
    666 
    667     if (!baseURL.isEmpty() && baseURL != blankURL() && baseURL != document.baseURL())
    668         completeURLs(*fragment, baseURL);
    669 
    670     return fragment.release();
    671 }
    672 
    673 static const char fragmentMarkerTag[] = "webkit-fragment-marker";
    674 
    675 static bool findNodesSurroundingContext(Document* document, RefPtrWillBeRawPtr<Comment>& nodeBeforeContext, RefPtrWillBeRawPtr<Comment>& nodeAfterContext)
    676 {
    677     for (Node* node = document->firstChild(); node; node = NodeTraversal::next(*node)) {
    678         if (node->nodeType() == Node::COMMENT_NODE && toComment(node)->data() == fragmentMarkerTag) {
    679             if (!nodeBeforeContext)
    680                 nodeBeforeContext = toComment(node);
    681             else {
    682                 nodeAfterContext = toComment(node);
    683                 return true;
    684             }
    685         }
    686     }
    687     return false;
    688 }
    689 
    690 static void trimFragment(DocumentFragment* fragment, Comment* nodeBeforeContext, Comment* nodeAfterContext)
    691 {
    692     RefPtrWillBeRawPtr<Node> next = nullptr;
    693     for (RefPtrWillBeRawPtr<Node> node = fragment->firstChild(); node; node = next) {
    694         if (nodeBeforeContext->isDescendantOf(node.get())) {
    695             next = NodeTraversal::next(*node);
    696             continue;
    697         }
    698         next = NodeTraversal::nextSkippingChildren(*node);
    699         ASSERT(!node->contains(nodeAfterContext));
    700         node->parentNode()->removeChild(node.get(), ASSERT_NO_EXCEPTION);
    701         if (nodeBeforeContext == node)
    702             break;
    703     }
    704 
    705     ASSERT(nodeAfterContext->parentNode());
    706     for (RefPtrWillBeRawPtr<Node> node = nodeAfterContext; node; node = next) {
    707         next = NodeTraversal::nextSkippingChildren(*node);
    708         node->parentNode()->removeChild(node.get(), ASSERT_NO_EXCEPTION);
    709     }
    710 }
    711 
    712 PassRefPtrWillBeRawPtr<DocumentFragment> createFragmentFromMarkupWithContext(Document& document, const String& markup, unsigned fragmentStart, unsigned fragmentEnd,
    713     const String& baseURL, ParserContentPolicy parserContentPolicy)
    714 {
    715     // FIXME: Need to handle the case where the markup already contains these markers.
    716 
    717     StringBuilder taggedMarkup;
    718     taggedMarkup.append(markup.left(fragmentStart));
    719     MarkupAccumulator::appendComment(taggedMarkup, fragmentMarkerTag);
    720     taggedMarkup.append(markup.substring(fragmentStart, fragmentEnd - fragmentStart));
    721     MarkupAccumulator::appendComment(taggedMarkup, fragmentMarkerTag);
    722     taggedMarkup.append(markup.substring(fragmentEnd));
    723 
    724     RefPtrWillBeRawPtr<DocumentFragment> taggedFragment = createFragmentFromMarkup(document, taggedMarkup.toString(), baseURL, parserContentPolicy);
    725     RefPtrWillBeRawPtr<Document> taggedDocument = Document::create();
    726     taggedDocument->setContextFeatures(document.contextFeatures());
    727 
    728     // FIXME: It's not clear what this code is trying to do. It puts nodes as direct children of a
    729     // Document that are not normally allowed by using the parser machinery.
    730     taggedDocument->parserTakeAllChildrenFrom(*taggedFragment);
    731 
    732     RefPtrWillBeRawPtr<Comment> nodeBeforeContext = nullptr;
    733     RefPtrWillBeRawPtr<Comment> nodeAfterContext = nullptr;
    734     if (!findNodesSurroundingContext(taggedDocument.get(), nodeBeforeContext, nodeAfterContext))
    735         return nullptr;
    736 
    737     RefPtrWillBeRawPtr<Range> range = Range::create(*taggedDocument.get(),
    738         positionAfterNode(nodeBeforeContext.get()).parentAnchoredEquivalent(),
    739         positionBeforeNode(nodeAfterContext.get()).parentAnchoredEquivalent());
    740 
    741     Node* commonAncestor = range->commonAncestorContainer();
    742     HTMLElement* specialCommonAncestor = ancestorToRetainStructureAndAppearanceWithNoRenderer(commonAncestor);
    743 
    744     // When there's a special common ancestor outside of the fragment, we must include it as well to
    745     // preserve the structure and appearance of the fragment. For example, if the fragment contains
    746     // TD, we need to include the enclosing TABLE tag as well.
    747     RefPtrWillBeRawPtr<DocumentFragment> fragment = DocumentFragment::create(document);
    748     if (specialCommonAncestor)
    749         fragment->appendChild(specialCommonAncestor);
    750     else
    751         fragment->parserTakeAllChildrenFrom(toContainerNode(*commonAncestor));
    752 
    753     trimFragment(fragment.get(), nodeBeforeContext.get(), nodeAfterContext.get());
    754 
    755     return fragment;
    756 }
    757 
    758 String createMarkup(const Node* node, EChildrenOnly childrenOnly, WillBeHeapVector<RawPtrWillBeMember<Node> >* nodes, EAbsoluteURLs shouldResolveURLs, Vector<QualifiedName>* tagNamesToSkip)
    759 {
    760     if (!node)
    761         return "";
    762 
    763     MarkupAccumulator accumulator(nodes, shouldResolveURLs);
    764     return accumulator.serializeNodes(const_cast<Node&>(*node), childrenOnly, tagNamesToSkip);
    765 }
    766 
    767 static void fillContainerFromString(ContainerNode* paragraph, const String& string)
    768 {
    769     Document& document = paragraph->document();
    770 
    771     if (string.isEmpty()) {
    772         paragraph->appendChild(createBlockPlaceholderElement(document));
    773         return;
    774     }
    775 
    776     ASSERT(string.find('\n') == kNotFound);
    777 
    778     Vector<String> tabList;
    779     string.split('\t', true, tabList);
    780     StringBuilder tabText;
    781     bool first = true;
    782     size_t numEntries = tabList.size();
    783     for (size_t i = 0; i < numEntries; ++i) {
    784         const String& s = tabList[i];
    785 
    786         // append the non-tab textual part
    787         if (!s.isEmpty()) {
    788             if (!tabText.isEmpty()) {
    789                 paragraph->appendChild(createTabSpanElement(document, tabText.toString()));
    790                 tabText.clear();
    791             }
    792             RefPtrWillBeRawPtr<Text> textNode = document.createTextNode(stringWithRebalancedWhitespace(s, first, i + 1 == numEntries));
    793             paragraph->appendChild(textNode.release());
    794         }
    795 
    796         // there is a tab after every entry, except the last entry
    797         // (if the last character is a tab, the list gets an extra empty entry)
    798         if (i + 1 != numEntries)
    799             tabText.append('\t');
    800         else if (!tabText.isEmpty())
    801             paragraph->appendChild(createTabSpanElement(document, tabText.toString()));
    802 
    803         first = false;
    804     }
    805 }
    806 
    807 bool isPlainTextMarkup(Node* node)
    808 {
    809     ASSERT(node);
    810     if (!isHTMLDivElement(*node))
    811         return false;
    812 
    813     HTMLDivElement& element = toHTMLDivElement(*node);
    814     if (!element.hasAttributes())
    815         return false;
    816 
    817     if (element.hasOneChild())
    818         return element.firstChild()->isTextNode() || element.firstChild()->hasChildren();
    819 
    820     return element.hasChildCount(2) && isTabHTMLSpanElementTextNode(element.firstChild()->firstChild()) && element.lastChild()->isTextNode();
    821 }
    822 
    823 static bool shouldPreserveNewline(const Range& range)
    824 {
    825     if (Node* node = range.firstNode()) {
    826         if (RenderObject* renderer = node->renderer())
    827             return renderer->style()->preserveNewline();
    828     }
    829 
    830     if (Node* node = range.startPosition().anchorNode()) {
    831         if (RenderObject* renderer = node->renderer())
    832             return renderer->style()->preserveNewline();
    833     }
    834 
    835     return false;
    836 }
    837 
    838 PassRefPtrWillBeRawPtr<DocumentFragment> createFragmentFromText(Range* context, const String& text)
    839 {
    840     if (!context)
    841         return nullptr;
    842 
    843     Document& document = context->ownerDocument();
    844     RefPtrWillBeRawPtr<DocumentFragment> fragment = document.createDocumentFragment();
    845 
    846     if (text.isEmpty())
    847         return fragment.release();
    848 
    849     String string = text;
    850     string.replace("\r\n", "\n");
    851     string.replace('\r', '\n');
    852 
    853     if (shouldPreserveNewline(*context)) {
    854         fragment->appendChild(document.createTextNode(string));
    855         if (string.endsWith('\n')) {
    856             RefPtrWillBeRawPtr<HTMLBRElement> element = createBreakElement(document);
    857             element->setAttribute(classAttr, AppleInterchangeNewline);
    858             fragment->appendChild(element.release());
    859         }
    860         return fragment.release();
    861     }
    862 
    863     // A string with no newlines gets added inline, rather than being put into a paragraph.
    864     if (string.find('\n') == kNotFound) {
    865         fillContainerFromString(fragment.get(), string);
    866         return fragment.release();
    867     }
    868 
    869     // Break string into paragraphs. Extra line breaks turn into empty paragraphs.
    870     Element* block = enclosingBlock(context->firstNode());
    871     bool useClonesOfEnclosingBlock = block
    872         && !isHTMLBodyElement(*block)
    873         && !isHTMLHtmlElement(*block)
    874         && block != editableRootForPosition(context->startPosition());
    875     bool useLineBreak = enclosingTextFormControl(context->startPosition());
    876 
    877     Vector<String> list;
    878     string.split('\n', true, list); // true gets us empty strings in the list
    879     size_t numLines = list.size();
    880     for (size_t i = 0; i < numLines; ++i) {
    881         const String& s = list[i];
    882 
    883         RefPtrWillBeRawPtr<Element> element = nullptr;
    884         if (s.isEmpty() && i + 1 == numLines) {
    885             // For last line, use the "magic BR" rather than a P.
    886             element = createBreakElement(document);
    887             element->setAttribute(classAttr, AppleInterchangeNewline);
    888         } else if (useLineBreak) {
    889             element = createBreakElement(document);
    890             fillContainerFromString(fragment.get(), s);
    891         } else {
    892             if (useClonesOfEnclosingBlock)
    893                 element = block->cloneElementWithoutChildren();
    894             else
    895                 element = createDefaultParagraphElement(document);
    896             fillContainerFromString(element.get(), s);
    897         }
    898         fragment->appendChild(element.release());
    899     }
    900     return fragment.release();
    901 }
    902 
    903 String urlToMarkup(const KURL& url, const String& title)
    904 {
    905     StringBuilder markup;
    906     markup.appendLiteral("<a href=\"");
    907     markup.append(url.string());
    908     markup.appendLiteral("\">");
    909     MarkupAccumulator::appendCharactersReplacingEntities(markup, title, 0, title.length(), EntityMaskInPCDATA);
    910     markup.appendLiteral("</a>");
    911     return markup.toString();
    912 }
    913 
    914 PassRefPtrWillBeRawPtr<DocumentFragment> createFragmentForInnerOuterHTML(const String& markup, Element* contextElement, ParserContentPolicy parserContentPolicy, const char* method, ExceptionState& exceptionState)
    915 {
    916     ASSERT(contextElement);
    917     Document& document = isHTMLTemplateElement(*contextElement) ? contextElement->document().ensureTemplateDocument() : contextElement->document();
    918     RefPtrWillBeRawPtr<DocumentFragment> fragment = DocumentFragment::create(document);
    919 
    920     if (document.isHTMLDocument()) {
    921         fragment->parseHTML(markup, contextElement, parserContentPolicy);
    922         return fragment;
    923     }
    924 
    925     bool wasValid = fragment->parseXML(markup, contextElement, parserContentPolicy);
    926     if (!wasValid) {
    927         exceptionState.throwDOMException(SyntaxError, "The provided markup is invalid XML, and therefore cannot be inserted into an XML document.");
    928         return nullptr;
    929     }
    930     return fragment.release();
    931 }
    932 
    933 PassRefPtrWillBeRawPtr<DocumentFragment> createFragmentForTransformToFragment(const String& sourceString, const String& sourceMIMEType, Document& outputDoc)
    934 {
    935     RefPtrWillBeRawPtr<DocumentFragment> fragment = outputDoc.createDocumentFragment();
    936 
    937     if (sourceMIMEType == "text/html") {
    938         // As far as I can tell, there isn't a spec for how transformToFragment is supposed to work.
    939         // Based on the documentation I can find, it looks like we want to start parsing the fragment in the InBody insertion mode.
    940         // Unfortunately, that's an implementation detail of the parser.
    941         // We achieve that effect here by passing in a fake body element as context for the fragment.
    942         RefPtrWillBeRawPtr<HTMLBodyElement> fakeBody = HTMLBodyElement::create(outputDoc);
    943         fragment->parseHTML(sourceString, fakeBody.get());
    944     } else if (sourceMIMEType == "text/plain") {
    945         fragment->parserAppendChild(Text::create(outputDoc, sourceString));
    946     } else {
    947         bool successfulParse = fragment->parseXML(sourceString, 0);
    948         if (!successfulParse)
    949             return nullptr;
    950     }
    951 
    952     // FIXME: Do we need to mess with URLs here?
    953 
    954     return fragment.release();
    955 }
    956 
    957 static inline void removeElementPreservingChildren(PassRefPtrWillBeRawPtr<DocumentFragment> fragment, HTMLElement* element)
    958 {
    959     RefPtrWillBeRawPtr<Node> nextChild = nullptr;
    960     for (RefPtrWillBeRawPtr<Node> child = element->firstChild(); child; child = nextChild) {
    961         nextChild = child->nextSibling();
    962         element->removeChild(child.get());
    963         fragment->insertBefore(child, element);
    964     }
    965     fragment->removeChild(element);
    966 }
    967 
    968 static inline bool isSupportedContainer(Element* element)
    969 {
    970     ASSERT(element);
    971     if (!element->isHTMLElement())
    972         return true;
    973 
    974     HTMLElement& htmlElement = toHTMLElement(*element);
    975     if (htmlElement.hasTagName(colTag) || htmlElement.hasTagName(colgroupTag) || htmlElement.hasTagName(framesetTag)
    976         || htmlElement.hasTagName(headTag) || htmlElement.hasTagName(styleTag) || htmlElement.hasTagName(titleTag)) {
    977         return false;
    978     }
    979     return !htmlElement.ieForbidsInsertHTML();
    980 }
    981 
    982 PassRefPtrWillBeRawPtr<DocumentFragment> createContextualFragment(const String& markup, Element* element, ParserContentPolicy parserContentPolicy, ExceptionState& exceptionState)
    983 {
    984     ASSERT(element);
    985     if (!isSupportedContainer(element)) {
    986         exceptionState.throwDOMException(NotSupportedError, "The range's container is '" + element->localName() + "', which is not supported.");
    987         return nullptr;
    988     }
    989 
    990     RefPtrWillBeRawPtr<DocumentFragment> fragment = createFragmentForInnerOuterHTML(markup, element, parserContentPolicy, "createContextualFragment", exceptionState);
    991     if (!fragment)
    992         return nullptr;
    993 
    994     // We need to pop <html> and <body> elements and remove <head> to
    995     // accommodate folks passing complete HTML documents to make the
    996     // child of an element.
    997 
    998     RefPtrWillBeRawPtr<Node> nextNode = nullptr;
    999     for (RefPtrWillBeRawPtr<Node> node = fragment->firstChild(); node; node = nextNode) {
   1000         nextNode = node->nextSibling();
   1001         if (isHTMLHtmlElement(*node) || isHTMLHeadElement(*node) || isHTMLBodyElement(*node)) {
   1002             HTMLElement* element = toHTMLElement(node);
   1003             if (Node* firstChild = element->firstChild())
   1004                 nextNode = firstChild;
   1005             removeElementPreservingChildren(fragment, element);
   1006         }
   1007     }
   1008     return fragment.release();
   1009 }
   1010 
   1011 void replaceChildrenWithFragment(ContainerNode* container, PassRefPtrWillBeRawPtr<DocumentFragment> fragment, ExceptionState& exceptionState)
   1012 {
   1013     ASSERT(container);
   1014     RefPtrWillBeRawPtr<ContainerNode> containerNode(container);
   1015 
   1016     ChildListMutationScope mutation(*containerNode);
   1017 
   1018     if (!fragment->firstChild()) {
   1019         containerNode->removeChildren();
   1020         return;
   1021     }
   1022 
   1023     // FIXME: This is wrong if containerNode->firstChild() has more than one ref!
   1024     if (containerNode->hasOneTextChild() && fragment->hasOneTextChild()) {
   1025         toText(containerNode->firstChild())->setData(toText(fragment->firstChild())->data());
   1026         return;
   1027     }
   1028 
   1029     // FIXME: No need to replace the child it is a text node and its contents are already == text.
   1030     if (containerNode->hasOneChild()) {
   1031         containerNode->replaceChild(fragment, containerNode->firstChild(), exceptionState);
   1032         return;
   1033     }
   1034 
   1035     containerNode->removeChildren();
   1036     containerNode->appendChild(fragment, exceptionState);
   1037 }
   1038 
   1039 void replaceChildrenWithText(ContainerNode* container, const String& text, ExceptionState& exceptionState)
   1040 {
   1041     ASSERT(container);
   1042     RefPtrWillBeRawPtr<ContainerNode> containerNode(container);
   1043 
   1044     ChildListMutationScope mutation(*containerNode);
   1045 
   1046     // FIXME: This is wrong if containerNode->firstChild() has more than one ref! Example:
   1047     // <div>foo</div>
   1048     // <script>
   1049     // var oldText = div.firstChild;
   1050     // console.log(oldText.data); // foo
   1051     // div.innerText = "bar";
   1052     // console.log(oldText.data); // bar!?!
   1053     // </script>
   1054     // I believe this is an intentional benchmark cheat from years ago.
   1055     // We should re-visit if we actually want this still.
   1056     if (containerNode->hasOneTextChild()) {
   1057         toText(containerNode->firstChild())->setData(text);
   1058         return;
   1059     }
   1060 
   1061     // NOTE: This method currently always creates a text node, even if that text node will be empty.
   1062     RefPtrWillBeRawPtr<Text> textNode = Text::create(containerNode->document(), text);
   1063 
   1064     // FIXME: No need to replace the child it is a text node and its contents are already == text.
   1065     if (containerNode->hasOneChild()) {
   1066         containerNode->replaceChild(textNode.release(), containerNode->firstChild(), exceptionState);
   1067         return;
   1068     }
   1069 
   1070     containerNode->removeChildren();
   1071     containerNode->appendChild(textNode.release(), exceptionState);
   1072 }
   1073 
   1074 void mergeWithNextTextNode(Text* textNode, ExceptionState& exceptionState)
   1075 {
   1076     ASSERT(textNode);
   1077     Node* next = textNode->nextSibling();
   1078     if (!next || !next->isTextNode())
   1079         return;
   1080 
   1081     RefPtrWillBeRawPtr<Text> textNext = toText(next);
   1082     textNode->appendData(textNext->data());
   1083     if (textNext->parentNode()) // Might have been removed by mutation event.
   1084         textNext->remove(exceptionState);
   1085 }
   1086 
   1087 String createStyledMarkupForNavigationTransition(Node* node)
   1088 {
   1089     node->document().updateLayoutIgnorePendingStylesheets();
   1090 
   1091     StyledMarkupAccumulator accumulator(0, ResolveAllURLs, AnnotateForNavigationTransition, nullptr, 0);
   1092     accumulator.serializeNodes(node, NodeTraversal::nextSkippingChildren(*node));
   1093 
   1094     static const char* documentMarkup = "<!DOCTYPE html><meta name=\"viewport\" content=\"width=device-width, user-scalable=0\">";
   1095     return documentMarkup + accumulator.takeResults();
   1096 }
   1097 
   1098 }
   1099