pjs/parser/html/nsHtml5TreeOperation.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 sw=2 et tw=78: */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Communicator client code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Pierre Phaneuf <pp@ludusdesign.com>
 *   Henri Sivonen <hsivonen@iki.fi>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#include "nsHtml5TreeOperation.h"
#include "nsContentUtils.h"
#include "nsNodeUtils.h"
#include "nsAttrName.h"
#include "nsHtml5TreeBuilder.h"
#include "nsIDOMMutationEvent.h"
#include "mozAutoDocUpdate.h"
#include "nsBindingManager.h"
#include "nsXBLBinding.h"
#include "nsHtml5DocumentMode.h"
#include "nsHtml5HtmlAttributes.h"
#include "nsContentCreatorFunctions.h"
#include "nsIScriptElement.h"
#include "nsIDTD.h"
#include "nsTraceRefcnt.h"
#include "nsIDOMHTMLFormElement.h"
#include "nsIFormControl.h"
#include "nsIStyleSheetLinkingElement.h"
#include "nsIDOMDocumentType.h"
#include "nsIMutationObserver.h"
#include "nsIFormProcessor.h"
#include "nsIServiceManager.h"

static NS_DEFINE_CID(kFormProcessorCID, NS_FORMPROCESSOR_CID);

/**
 * Helper class that opens a notification batch if the current doc
 * is different from the executor doc.
 */
class NS_STACK_CLASS nsHtml5OtherDocUpdate {
  public:
    nsHtml5OtherDocUpdate(nsIDocument* aCurrentDoc, nsIDocument* aExecutorDoc)
    {
      NS_PRECONDITION(aCurrentDoc, "Node has no doc?");
      NS_PRECONDITION(aExecutorDoc, "Executor has no doc?");
      if (NS_LIKELY(aCurrentDoc == aExecutorDoc)) {
        mDocument = nsnull;
      } else {
        mDocument = aCurrentDoc;
        aCurrentDoc->BeginUpdate(UPDATE_CONTENT_MODEL);        
      }
    }

    ~nsHtml5OtherDocUpdate()
    {
      if (NS_UNLIKELY(mDocument)) {
        mDocument->EndUpdate(UPDATE_CONTENT_MODEL);
      }
    }
  private:
    nsIDocument* mDocument;
};

nsHtml5TreeOperation::nsHtml5TreeOperation()
#ifdef DEBUG
 : mOpCode(eTreeOpUninitialized)
#endif
{
  MOZ_COUNT_CTOR(nsHtml5TreeOperation);
}

nsHtml5TreeOperation::~nsHtml5TreeOperation()
{
  MOZ_COUNT_DTOR(nsHtml5TreeOperation);
  NS_ASSERTION(mOpCode != eTreeOpUninitialized, "Uninitialized tree op.");
  switch(mOpCode) {
    case eTreeOpAddAttributes:
      delete mTwo.attributes;
      break;
    case eTreeOpCreateElementNetwork:
    case eTreeOpCreateElementNotNetwork:
      delete mThree.attributes;
      break;
    case eTreeOpAppendDoctypeToDocument:
      delete mTwo.stringPair;
      break;
    case eTreeOpFosterParentText:
    case eTreeOpAppendText:
    case eTreeOpAppendComment:
    case eTreeOpAppendCommentToDocument:
      delete[] mTwo.unicharPtr;
      break;
    case eTreeOpSetDocumentCharset:
    case eTreeOpNeedsCharsetSwitchTo:
      delete[] mOne.charPtr;
      break;
    case eTreeOpProcessOfflineManifest:
      nsMemory::Free(mOne.unicharPtr);
      break;
    default: // keep the compiler happy
      break;
  }
}

nsresult
nsHtml5TreeOperation::AppendTextToTextNode(const PRUnichar* aBuffer,
                                           PRInt32 aLength,
                                           nsIContent* aTextNode,
                                           nsHtml5TreeOpExecutor* aBuilder)
{
  NS_PRECONDITION(aTextNode, "Got null text node.");

  if (aBuilder->HaveNotified(aTextNode)) {
    // This text node has already been notified on, so it's necessary to
    // notify on the append
    nsresult rv = NS_OK;
    PRUint32 oldLength = aTextNode->TextLength();
    CharacterDataChangeInfo info = {
      PR_TRUE,
      oldLength,
      oldLength,
      aLength
    };
    nsNodeUtils::CharacterDataWillChange(aTextNode, &info);

    rv = aTextNode->AppendText(aBuffer, aLength, PR_FALSE);
    NS_ENSURE_SUCCESS(rv, rv);

    nsNodeUtils::CharacterDataChanged(aTextNode, &info);
    return rv;
  }

  return aTextNode->AppendText(aBuffer, aLength, PR_FALSE);
}


nsresult
nsHtml5TreeOperation::AppendText(const PRUnichar* aBuffer,
                                 PRInt32 aLength,
                                 nsIContent* aParent,
                                 nsHtml5TreeOpExecutor* aBuilder)
{
  nsresult rv = NS_OK;
  nsIContent* lastChild = aParent->GetLastChild();
  if (lastChild && lastChild->IsNodeOfType(nsINode::eTEXT)) {
    nsHtml5OtherDocUpdate update(aParent->GetOwnerDoc(),
                                 aBuilder->GetDocument());
    return AppendTextToTextNode(aBuffer, 
                                aLength, 
                                lastChild, 
                                aBuilder);
  }

  nsCOMPtr<nsIContent> text;
  NS_NewTextNode(getter_AddRefs(text), aBuilder->GetNodeInfoManager());
  NS_ASSERTION(text, "Infallible malloc failed?");
  rv = text->SetText(aBuffer, aLength, PR_FALSE);
  NS_ENSURE_SUCCESS(rv, rv);

  return Append(text, aParent, aBuilder);
}

nsresult
nsHtml5TreeOperation::Append(nsIContent* aNode,
                             nsIContent* aParent,
                             nsHtml5TreeOpExecutor* aBuilder)
{
  nsresult rv = NS_OK;
  nsIDocument* executorDoc = aBuilder->GetDocument();
  NS_ASSERTION(executorDoc, "Null doc on executor");
  nsIDocument* parentDoc = aParent->GetOwnerDoc();
  NS_ASSERTION(parentDoc, "Null owner doc on old node.");

  if (NS_LIKELY(executorDoc == parentDoc)) {
    // the usual case. the parent is in the parser's doc
    aBuilder->PostPendingAppendNotification(aParent, aNode);
    rv = aParent->AppendChildTo(aNode, PR_FALSE);
    return rv;
  }

  // The parent has been moved to another doc
  parentDoc->BeginUpdate(UPDATE_CONTENT_MODEL);

  PRUint32 childCount = aParent->GetChildCount();
  rv = aParent->AppendChildTo(aNode, PR_FALSE);
  nsNodeUtils::ContentAppended(aParent, aNode, childCount);

  parentDoc->EndUpdate(UPDATE_CONTENT_MODEL);
  return rv;
}

nsresult
nsHtml5TreeOperation::AppendToDocument(nsIContent* aNode,
                                       nsHtml5TreeOpExecutor* aBuilder)
{
  nsresult rv = NS_OK;
  aBuilder->FlushPendingAppendNotifications();
  nsIDocument* doc = aBuilder->GetDocument();
  PRUint32 childCount = doc->GetChildCount();
  rv = doc->AppendChildTo(aNode, PR_FALSE);
  NS_ENSURE_SUCCESS(rv, rv);
  nsNodeUtils::ContentInserted(doc, aNode, childCount);
  return rv;
}

nsresult
nsHtml5TreeOperation::Perform(nsHtml5TreeOpExecutor* aBuilder,
                              nsIContent** aScriptElement)
{
  nsresult rv = NS_OK;
  switch(mOpCode) {
    case eTreeOpAppend: {
      nsIContent* node = *(mOne.node);
      nsIContent* parent = *(mTwo.node);
      return Append(node, parent, aBuilder);
    }
    case eTreeOpDetach: {
      nsIContent* node = *(mOne.node);
      aBuilder->FlushPendingAppendNotifications();
      nsIContent* parent = node->GetParent();
      if (parent) {
        nsHtml5OtherDocUpdate update(parent->GetOwnerDoc(),
                                     aBuilder->GetDocument());
        PRUint32 pos = parent->IndexOf(node);
        NS_ASSERTION((pos >= 0), "Element not found as child of its parent");
        rv = parent->RemoveChildAt(pos, PR_TRUE, PR_FALSE);
        NS_ENSURE_SUCCESS(rv, rv);
      }
      return rv;
    }
    case eTreeOpAppendChildrenToNewParent: {
      nsIContent* node = *(mOne.node);
      nsIContent* parent = *(mTwo.node);
      aBuilder->FlushPendingAppendNotifications();

      nsHtml5OtherDocUpdate update(parent->GetOwnerDoc(),
                                   aBuilder->GetDocument());

      PRUint32 childCount = parent->GetChildCount();
      PRBool didAppend = PR_FALSE;
      while (node->GetChildCount()) {
        nsCOMPtr<nsIContent> child = node->GetChildAt(0);
        rv = node->RemoveChildAt(0, PR_TRUE, PR_FALSE);
        NS_ENSURE_SUCCESS(rv, rv);
        rv = parent->AppendChildTo(child, PR_FALSE);
        NS_ENSURE_SUCCESS(rv, rv);
        didAppend = PR_TRUE;
      }
      if (didAppend) {
        nsNodeUtils::ContentAppended(parent, parent->GetChildAt(childCount),
                                     childCount);
      }
      return rv;
    }
    case eTreeOpFosterParent: {
      nsIContent* node = *(mOne.node);
      nsIContent* parent = *(mTwo.node);
      nsIContent* table = *(mThree.node);
      nsIContent* foster = table->GetParent();

      if (foster && foster->IsElement()) {
        aBuilder->FlushPendingAppendNotifications();

        nsHtml5OtherDocUpdate update(foster->GetOwnerDoc(),
                                     aBuilder->GetDocument());

        PRUint32 pos = foster->IndexOf(table);
        rv = foster->InsertChildAt(node, pos, PR_FALSE);
        NS_ENSURE_SUCCESS(rv, rv);
        nsNodeUtils::ContentInserted(foster, node, pos);
        return rv;
      }

      return Append(node, parent, aBuilder);
    }
    case eTreeOpAppendToDocument: {
      nsIContent* node = *(mOne.node);
      return AppendToDocument(node, aBuilder);
    }
    case eTreeOpAddAttributes: {
      nsIContent* node = *(mOne.node);
      nsHtml5HtmlAttributes* attributes = mTwo.attributes;

      nsHtml5OtherDocUpdate update(node->GetOwnerDoc(),
                                   aBuilder->GetDocument());

      nsIDocument* document = node->GetCurrentDoc();

      PRInt32 len = attributes->getLength();
      for (PRInt32 i = len; i > 0;) {
        --i;
        // prefix doesn't need regetting. it is always null or a static atom
        // local name is never null
        nsCOMPtr<nsIAtom> localName = Reget(attributes->getLocalName(i));
        PRInt32 nsuri = attributes->getURI(i);
        if (!node->HasAttr(nsuri, localName)) {

          // the manual notification code is based on nsGenericElement
          
          PRUint32 stateMask = PRUint32(node->IntrinsicState());
          nsNodeUtils::AttributeWillChange(node, 
                                           nsuri,
                                           localName,
                                           static_cast<PRUint8>(nsIDOMMutationEvent::ADDITION));

          // prefix doesn't need regetting. it is always null or a static atom
          // local name is never null
          node->SetAttr(nsuri, localName, attributes->getPrefix(i), *(attributes->getValue(i)), PR_FALSE);
          // XXX what to do with nsresult?
          
          if (document || node->HasFlag(NODE_FORCE_XBL_BINDINGS)) {
            nsIDocument* ownerDoc = node->GetOwnerDoc();
            if (ownerDoc) {
              nsRefPtr<nsXBLBinding> binding =
                ownerDoc->BindingManager()->GetBinding(node);
              if (binding) {
                binding->AttributeChanged(localName, nsuri, PR_FALSE, PR_FALSE);
              }
            }
          }
          
          stateMask ^= PRUint32(node->IntrinsicState());
          if (stateMask && document) {
            MOZ_AUTO_DOC_UPDATE(document, UPDATE_CONTENT_STATE, PR_TRUE);
            document->ContentStatesChanged(node, nsnull, stateMask);
          }
          nsNodeUtils::AttributeChanged(node, 
                                        nsuri, 
                                        localName, 
                                        static_cast<PRUint8>(nsIDOMMutationEvent::ADDITION));
        }
      }
      
      return rv;
    }
    case eTreeOpCreateElementNetwork:
    case eTreeOpCreateElementNotNetwork: {
      nsIContent** target = mOne.node;
      PRInt32 ns = mInt;
      nsCOMPtr<nsIAtom> name = Reget(mTwo.atom);
      nsHtml5HtmlAttributes* attributes = mThree.attributes;
      
      PRBool isKeygen = (name == nsHtml5Atoms::keygen && ns == kNameSpaceID_XHTML);
      if (NS_UNLIKELY(isKeygen)) {
        name = nsHtml5Atoms::select;
      }
      
      nsCOMPtr<nsIContent> newContent;
      nsCOMPtr<nsINodeInfo> nodeInfo = aBuilder->GetNodeInfoManager()->GetNodeInfo(name, nsnull, ns);
      NS_ASSERTION(nodeInfo, "Got null nodeinfo.");
      NS_NewElement(getter_AddRefs(newContent),
                    nodeInfo->NamespaceID(),
                    nodeInfo,
                    (mOpCode == eTreeOpCreateElementNetwork ?
                     NS_FROM_PARSER_NETWORK
                     : (aBuilder->IsFragmentMode() ?
                        NS_FROM_PARSER_FRAGMENT :
                        NS_FROM_PARSER_DOCUMENT_WRITE)));
      NS_ASSERTION(newContent, "Element creation created null pointer.");

      aBuilder->HoldElement(*target = newContent);      

      if (NS_UNLIKELY(name == nsHtml5Atoms::style || name == nsHtml5Atoms::link)) {
        nsCOMPtr<nsIStyleSheetLinkingElement> ssle(do_QueryInterface(newContent));
        if (ssle) {
          ssle->InitStyleLinkElement(PR_FALSE);
          ssle->SetEnableUpdates(PR_FALSE);
        }
      } else if (NS_UNLIKELY(isKeygen)) {
        // Adapted from CNavDTD
        nsCOMPtr<nsIFormProcessor> theFormProcessor =
          do_GetService(kFormProcessorCID, &rv);
        NS_ENSURE_SUCCESS(rv, rv);
        
        nsTArray<nsString> theContent;
        nsAutoString theAttribute;
         
        (void) theFormProcessor->ProvideContent(NS_LITERAL_STRING("select"),
                                                theContent,
                                                theAttribute);

        newContent->SetAttr(kNameSpaceID_None, 
                            nsGkAtoms::moztype, 
                            nsnull, 
                            theAttribute,
                            PR_FALSE);

        nsCOMPtr<nsINodeInfo> optionNodeInfo = 
          aBuilder->GetNodeInfoManager()->GetNodeInfo(nsHtml5Atoms::option, 
                                                      nsnull, 
                                                      kNameSpaceID_XHTML);
                                                      
        for (PRUint32 i = 0; i < theContent.Length(); ++i) {
          nsCOMPtr<nsIContent> optionElt;
          NS_NewElement(getter_AddRefs(optionElt), 
                        optionNodeInfo->NamespaceID(), 
                        optionNodeInfo, 
                        PR_TRUE);
          nsCOMPtr<nsIContent> optionText;
          NS_NewTextNode(getter_AddRefs(optionText), 
                         aBuilder->GetNodeInfoManager());
          (void) optionText->SetText(theContent[i], PR_FALSE);
          optionElt->AppendChildTo(optionText, PR_FALSE);
          newContent->AppendChildTo(optionElt, PR_FALSE);
          newContent->DoneAddingChildren(PR_FALSE);
        }
      } else if (name == nsHtml5Atoms::frameset && ns == kNameSpaceID_XHTML) {
        nsIDocument* doc = aBuilder->GetDocument();
        nsCOMPtr<nsIHTMLDocument> htmlDocument = do_QueryInterface(doc);
        if (htmlDocument) {
          // It seems harmless to call this multiple times, since this 
          // is a simple field setter
          htmlDocument->SetIsFrameset(PR_TRUE);
        }
      }

      if (!attributes) {
        return rv;
      }

      PRInt32 len = attributes->getLength();
      for (PRInt32 i = len; i > 0;) {
        --i;
        // prefix doesn't need regetting. it is always null or a static atom
        // local name is never null
        nsCOMPtr<nsIAtom> localName = Reget(attributes->getLocalName(i));
        newContent->SetAttr(attributes->getURI(i), localName, attributes->getPrefix(i), *(attributes->getValue(i)), PR_FALSE);
        // XXX what to do with nsresult?
      }

      return rv;
    }
    case eTreeOpSetFormElement: {
      nsIContent* node = *(mOne.node);
      nsIContent* parent = *(mTwo.node);
      nsCOMPtr<nsIFormControl> formControl(do_QueryInterface(node));
      // NS_ASSERTION(formControl, "Form-associated element did not implement nsIFormControl.");
      // TODO: uncomment the above line when <output> (bug 346485) and <keygen> (bug 101019) are supported by Gecko
      nsCOMPtr<nsIDOMHTMLFormElement> formElement(do_QueryInterface(parent));
      NS_ASSERTION(formElement, "The form element doesn't implement nsIDOMHTMLFormElement.");
      if (formControl) { // avoid crashing on <output> and <keygen>
        formControl->SetForm(formElement);
      }
      return rv;
    }
    case eTreeOpAppendText: {
      nsIContent* parent = *mOne.node;
      PRUnichar* buffer = mTwo.unicharPtr;
      PRInt32 length = mInt;
      return AppendText(buffer, length, parent, aBuilder);
    }
    case eTreeOpAppendIsindexPrompt: {
      nsIContent* parent = *mOne.node;
      nsXPIDLString prompt;
      nsresult rv =
          nsContentUtils::GetLocalizedString(nsContentUtils::eFORMS_PROPERTIES,
                                             "IsIndexPromptWithSpace", prompt);
      PRUint32 len = prompt.Length();
      if (NS_FAILED(rv)) {
        return rv;
      }
      if (!len) {
        // Don't bother appending a zero-length text node.
        return NS_OK;
      }
      return AppendText(prompt.BeginReading(), len, parent, aBuilder);
    }
    case eTreeOpFosterParentText: {
      nsIContent* stackParent = *mOne.node;
      PRUnichar* buffer = mTwo.unicharPtr;
      PRInt32 length = mInt;
      nsIContent* table = *mThree.node;
      
      nsIContent* foster = table->GetParent();

      if (foster && foster->IsElement()) {
        aBuilder->FlushPendingAppendNotifications();

        nsHtml5OtherDocUpdate update(foster->GetOwnerDoc(),
                                     aBuilder->GetDocument());

        PRUint32 pos = foster->IndexOf(table);
        
        nsIContent* previousSibling = foster->GetChildAt(pos - 1);
        if (previousSibling && previousSibling->IsNodeOfType(nsINode::eTEXT)) {
          return AppendTextToTextNode(buffer, 
                                      length, 
                                      previousSibling, 
                                      aBuilder);
        }
        
        nsCOMPtr<nsIContent> text;
        NS_NewTextNode(getter_AddRefs(text), aBuilder->GetNodeInfoManager());
        NS_ASSERTION(text, "Infallible malloc failed?");
        rv = text->SetText(buffer, length, PR_FALSE);
        NS_ENSURE_SUCCESS(rv, rv);
        
        rv = foster->InsertChildAt(text, pos, PR_FALSE);
        NS_ENSURE_SUCCESS(rv, rv);
        nsNodeUtils::ContentInserted(foster, text, pos);
        return rv;
      }
      
      return AppendText(buffer, length, stackParent, aBuilder);
    }
    case eTreeOpAppendComment: {
      nsIContent* parent = *mOne.node;
      PRUnichar* buffer = mTwo.unicharPtr;
      PRInt32 length = mInt;
      
      nsCOMPtr<nsIContent> comment;
      NS_NewCommentNode(getter_AddRefs(comment), aBuilder->GetNodeInfoManager());
      NS_ASSERTION(comment, "Infallible malloc failed?");
      rv = comment->SetText(buffer, length, PR_FALSE);
      NS_ENSURE_SUCCESS(rv, rv);
      
      return Append(comment, parent, aBuilder);
    }
    case eTreeOpAppendCommentToDocument: {
      PRUnichar* buffer = mTwo.unicharPtr;
      PRInt32 length = mInt;
      
      nsCOMPtr<nsIContent> comment;
      NS_NewCommentNode(getter_AddRefs(comment), aBuilder->GetNodeInfoManager());
      NS_ASSERTION(comment, "Infallible malloc failed?");
      rv = comment->SetText(buffer, length, PR_FALSE);
      NS_ENSURE_SUCCESS(rv, rv);
      
      return AppendToDocument(comment, aBuilder);
    }
    case eTreeOpAppendDoctypeToDocument: {
      nsCOMPtr<nsIAtom> name = Reget(mOne.atom);
      nsHtml5TreeOperationStringPair* pair = mTwo.stringPair;
      nsString publicId;
      nsString systemId;
      pair->Get(publicId, systemId);
      
      // Adapted from nsXMLContentSink
      // Create a new doctype node
      nsCOMPtr<nsIDOMDocumentType> docType;
      nsAutoString voidString;
      voidString.SetIsVoid(PR_TRUE);
      NS_NewDOMDocumentType(getter_AddRefs(docType),
                            aBuilder->GetNodeInfoManager(),
                            nsnull,
                            name,
                            nsnull,
                            nsnull,
                            publicId,
                            systemId,
                            voidString);
      NS_ASSERTION(docType, "Doctype creation failed.");
      nsCOMPtr<nsIContent> asContent = do_QueryInterface(docType);
      return AppendToDocument(asContent, aBuilder);
    }
    case eTreeOpRunScript: {
      nsIContent* node = *(mOne.node);
      nsAHtml5TreeBuilderState* snapshot = mTwo.state;
      if (snapshot) {
        aBuilder->InitializeDocWriteParserState(snapshot, mInt);
      }
      *aScriptElement = node;
      return rv;
    }
    case eTreeOpRunScriptAsyncDefer: {
      nsIContent* node = *(mOne.node);
      aBuilder->RunScript(node);
      return rv;
    }
    case eTreeOpDoneAddingChildren: {
      nsIContent* node = *(mOne.node);
      node->DoneAddingChildren(aBuilder->HaveNotified(node));
      return rv;
    }
    case eTreeOpDoneCreatingElement: {
      nsIContent* node = *(mOne.node);
      node->DoneCreatingElement();
      return rv;
    }
    case eTreeOpFlushPendingAppendNotifications: {
      aBuilder->FlushPendingAppendNotifications();
      return rv;
    }
    case eTreeOpSetDocumentCharset: {
      char* str = mOne.charPtr;
      PRInt32 charsetSource = mInt;
      nsDependentCString dependentString(str);
      aBuilder->SetDocumentCharsetAndSource(dependentString, charsetSource);
      return rv;
    }
    case eTreeOpNeedsCharsetSwitchTo: {
      char* str = mOne.charPtr;
      aBuilder->NeedsCharsetSwitchTo(str);
      return rv;    
    }
    case eTreeOpUpdateStyleSheet: {
      nsIContent* node = *(mOne.node);
      aBuilder->FlushPendingAppendNotifications();
      aBuilder->UpdateStyleSheet(node);
      return rv;
    }
    case eTreeOpProcessMeta: {
      nsIContent* node = *(mOne.node);
      rv = aBuilder->ProcessMETATag(node);
      return rv;
    }
    case eTreeOpProcessOfflineManifest: {
      PRUnichar* str = mOne.unicharPtr;
      nsDependentString dependentString(str);
      aBuilder->ProcessOfflineManifest(dependentString);
      return rv;
    }
    case eTreeOpMarkMalformedIfScript: {
      nsIContent* node = *(mOne.node);
      nsCOMPtr<nsIScriptElement> sele = do_QueryInterface(node);
      if (sele) {
        // Make sure to serialize this script correctly, for nice round tripping.
        sele->SetIsMalformed();
      }
      return rv;
    }
    case eTreeOpStreamEnded: {
      aBuilder->DidBuildModel(PR_FALSE); // this causes a notifications flush anyway
      return rv;
    }
    case eTreeOpStartLayout: {
      aBuilder->StartLayout(); // this causes a notification flush anyway
      return rv;
    }
    case eTreeOpDocumentMode: {
      aBuilder->SetDocumentMode(mOne.mode);
      return rv;
    }
    case eTreeOpSetStyleLineNumber: {
      nsIContent* node = *(mOne.node);
      nsCOMPtr<nsIStyleSheetLinkingElement> ssle = do_QueryInterface(node);
      NS_ASSERTION(ssle, "Node didn't QI to style.");
      ssle->SetLineNumber(mInt);
      return rv;
    }
    case eTreeOpSetScriptLineNumberAndFreeze: {
      nsIContent* node = *(mOne.node);
      nsCOMPtr<nsIScriptElement> sele = do_QueryInterface(node);
      NS_ASSERTION(sele, "Node didn't QI to script.");
      sele->SetScriptLineNumber(mInt);
      sele->FreezeUriAsyncDefer();
      return rv;
    }
    default: {
      NS_NOTREACHED("Bogus tree op");
    }
  }
  return rv; // keep compiler happy
}