text: /*
   * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
   *           (C) 1999 Antti Koivisto (koivisto@kde.org)
   *           (C) 2001 Dirk Mueller (mueller@kde.org)
   * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
   * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
   * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
   * Copyright (C) 2011 Google Inc. 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
   * version 2 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Library General Public License for more details.
   *
   * You should have received a copy of the GNU Library General Public License
   * along with this library; see the file COPYING.LIB.  If not, write to
   * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   * Boston, MA 02110-1301, USA.
   */
  #include "core/dom/TreeScopeAdopter.h"
  
  #include "core/dom/Attr.h"
  #include "core/dom/NodeRareData.h"
  #include "core/dom/NodeTraversal.h"
  #include "core/dom/shadow/ElementShadow.h"
  #include "core/dom/shadow/ShadowRoot.h"
  
  namespace blink {
  
  void TreeScopeAdopter::moveTreeToNewScope(Node& root) const
  {
      ASSERT(needsScopeChange());
  
  #if !ENABLE(OILPAN)
      oldScope().guardRef();
  #endif
  
      // If an element is moved from a document and then eventually back again the collection cache for
      // that element may contain stale data as changes made to it will have updated the DOMTreeVersion
      // of the document it was moved to. By increasing the DOMTreeVersion of the donating document here
      // we ensure that the collection cache will be invalidated as needed when the element is moved back.
      Document& oldDocument = oldScope().document();
      Document& newDocument = newScope().document();
      bool willMoveToNewDocument = oldDocument != newDocument;
      if (willMoveToNewDocument)
          oldDocument.incDOMTreeVersion();
  
      for (Node& node : NodeTraversal::inclusiveDescendantsOf(root)) {
          updateTreeScope(node);
  
          if (willMoveToNewDocument) {
              moveNodeToNewDocument(node, oldDocument, newDocument);
          } else if (node.hasRareData()) {
              NodeRareData* rareData = node.rareData();
              if (rareData->nodeLists())
                  rareData->nodeLists()->adoptTreeScope();
          }
  
          if (!node.isElementNode())
              continue;
          Element& element = toElement(node);
  
          if (WillBeHeapVector<RefPtrWillBeMember<Attr>>* attrs = element.attrNodeList()) {
              for (const auto& attr : *attrs)
                  moveTreeToNewScope(*attr);
          }
  
          for (ShadowRoot* shadow = element.youngestShadowRoot(); shadow; shadow = shadow->olderShadowRoot()) {
              shadow->setParentTreeScope(newScope());
              if (willMoveToNewDocument)
                  moveTreeToNewDocument(*shadow, oldDocument, newDocument);
          }
      }
  
  #if !ENABLE(OILPAN)
      oldScope().guardDeref();
  #endif
  }
  
  void TreeScopeAdopter::moveTreeToNewDocument(Node& root, Document& oldDocument, Document& newDocument) const
  {
      ASSERT(oldDocument != newDocument);
      for (Node& node : NodeTraversal::inclusiveDescendantsOf(root)) {
          moveNodeToNewDocument(node, oldDocument, newDocument);
  
          if (!node.isElementNode())
              continue;
          Element& element = toElement(node);
  
          if (WillBeHeapVector<RefPtrWillBeMember<Attr>>* attrs = element.attrNodeList()) {
              for (const auto& attr : *attrs)
                  moveTreeToNewDocument(*attr, oldDocument, newDocument);
          }
  
          for (ShadowRoot* shadow = element.youngestShadowRoot(); shadow; shadow = shadow->olderShadowRoot())
              moveTreeToNewDocument(*shadow, oldDocument, newDocument);
      }
  }
  
  #if ENABLE(ASSERT)
  static bool didMoveToNewDocumentWasCalled = false;
  static Document* oldDocumentDidMoveToNewDocumentWasCalledWith = 0;
  
  void TreeScopeAdopter::ensureDidMoveToNewDocumentWasCalled(Document& oldDocument)
  {
      ASSERT(!didMoveToNewDocumentWasCalled);
      ASSERT_UNUSED(oldDocument, oldDocument == oldDocumentDidMoveToNewDocumentWasCalledWith);
      didMoveToNewDocumentWasCalled = true;
  }
  #endif
  
  inline void TreeScopeAdopter::updateTreeScope(Node& node) const
  {
      ASSERT(!node.isTreeScope());
      ASSERT(node.treeScope() == oldScope());
  #if !ENABLE(OILPAN)
      newScope().guardRef();
      oldScope().guardDeref();
  #endif
      node.setTreeScope(m_newScope);
  }
  
  inline void TreeScopeAdopter::moveNodeToNewDocument(Node& node, Document& oldDocument, Document& newDocument) const
  {
      ASSERT(oldDocument != newDocument);
  
      if (node.hasRareData()) {
          NodeRareData* rareData = node.rareData();
          if (rareData->nodeLists())
              rareData->nodeLists()->adoptDocument(oldDocument, newDocument);
      }
  
      oldDocument.moveNodeIteratorsToNewDocument(node, newDocument);
  
      if (node.isShadowRoot())
          toShadowRoot(node).setDocument(newDocument);
  
  #if ENABLE(ASSERT)
      didMoveToNewDocumentWasCalled = false;
      oldDocumentDidMoveToNewDocumentWasCalledWith = &oldDocument;
  #endif
  
      node.didMoveToNewDocument(oldDocument);
      ASSERT(didMoveToNewDocumentWasCalled);
  }
  
  }
  