third_party/WebKit/Source/core/dom/MutationRecord.cpp

/*
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#include "core/dom/MutationRecord.h"

#include "core/dom/Node.h"
#include "core/dom/NodeList.h"
#include "core/dom/QualifiedName.h"
#include "core/dom/StaticNodeList.h"
#include "wtf/StdLibExtras.h"

namespace blink {

namespace {

class ChildListRecord : public MutationRecord {
 public:
  ChildListRecord(Node* target,
                  StaticNodeList* added,
                  StaticNodeList* removed,
                  Node* previousSibling,
                  Node* nextSibling)
      : m_target(target),
        m_addedNodes(added),
        m_removedNodes(removed),
        m_previousSibling(previousSibling),
        m_nextSibling(nextSibling) {}

  DEFINE_INLINE_VIRTUAL_TRACE() {
    visitor->trace(m_target);
    visitor->trace(m_addedNodes);
    visitor->trace(m_removedNodes);
    visitor->trace(m_previousSibling);
    visitor->trace(m_nextSibling);
    MutationRecord::trace(visitor);
  }

 private:
  const AtomicString& type() override;
  Node* target() override { return m_target.get(); }
  StaticNodeList* addedNodes() override { return m_addedNodes.get(); }
  StaticNodeList* removedNodes() override { return m_removedNodes.get(); }
  Node* previousSibling() override { return m_previousSibling.get(); }
  Node* nextSibling() override { return m_nextSibling.get(); }

  Member<Node> m_target;
  Member<StaticNodeList> m_addedNodes;
  Member<StaticNodeList> m_removedNodes;
  Member<Node> m_previousSibling;
  Member<Node> m_nextSibling;
};

class RecordWithEmptyNodeLists : public MutationRecord {
 public:
  RecordWithEmptyNodeLists(Node* target, const String& oldValue)
      : m_target(target), m_oldValue(oldValue) {}

  DEFINE_INLINE_VIRTUAL_TRACE() {
    visitor->trace(m_target);
    visitor->trace(m_addedNodes);
    visitor->trace(m_removedNodes);
    MutationRecord::trace(visitor);
  }

 private:
  Node* target() override { return m_target.get(); }
  String oldValue() override { return m_oldValue; }
  StaticNodeList* addedNodes() override {
    return lazilyInitializeEmptyNodeList(m_addedNodes);
  }
  StaticNodeList* removedNodes() override {
    return lazilyInitializeEmptyNodeList(m_removedNodes);
  }

  static StaticNodeList* lazilyInitializeEmptyNodeList(
      Member<StaticNodeList>& nodeList) {
    if (!nodeList)
      nodeList = StaticNodeList::createEmpty();
    return nodeList.get();
  }

  Member<Node> m_target;
  String m_oldValue;
  Member<StaticNodeList> m_addedNodes;
  Member<StaticNodeList> m_removedNodes;
};

class AttributesRecord : public RecordWithEmptyNodeLists {
 public:
  AttributesRecord(Node* target,
                   const QualifiedName& name,
                   const AtomicString& oldValue)
      : RecordWithEmptyNodeLists(target, oldValue),
        m_attributeName(name.localName()),
        m_attributeNamespace(name.namespaceURI()) {}

 private:
  const AtomicString& type() override;
  const AtomicString& attributeName() override { return m_attributeName; }
  const AtomicString& attributeNamespace() override {
    return m_attributeNamespace;
  }

  AtomicString m_attributeName;
  AtomicString m_attributeNamespace;
};

class CharacterDataRecord : public RecordWithEmptyNodeLists {
 public:
  CharacterDataRecord(Node* target, const String& oldValue)
      : RecordWithEmptyNodeLists(target, oldValue) {}

 private:
  const AtomicString& type() override;
};

class MutationRecordWithNullOldValue : public MutationRecord {
 public:
  MutationRecordWithNullOldValue(MutationRecord* record) : m_record(record) {}

  DEFINE_INLINE_VIRTUAL_TRACE() {
    visitor->trace(m_record);
    MutationRecord::trace(visitor);
  }

 private:
  const AtomicString& type() override { return m_record->type(); }
  Node* target() override { return m_record->target(); }
  StaticNodeList* addedNodes() override { return m_record->addedNodes(); }
  StaticNodeList* removedNodes() override { return m_record->removedNodes(); }
  Node* previousSibling() override { return m_record->previousSibling(); }
  Node* nextSibling() override { return m_record->nextSibling(); }
  const AtomicString& attributeName() override {
    return m_record->attributeName();
  }
  const AtomicString& attributeNamespace() override {
    return m_record->attributeNamespace();
  }

  String oldValue() override { return String(); }

  Member<MutationRecord> m_record;
};

const AtomicString& ChildListRecord::type() {
  DEFINE_STATIC_LOCAL(AtomicString, childList, ("childList"));
  return childList;
}

const AtomicString& AttributesRecord::type() {
  DEFINE_STATIC_LOCAL(AtomicString, attributes, ("attributes"));
  return attributes;
}

const AtomicString& CharacterDataRecord::type() {
  DEFINE_STATIC_LOCAL(AtomicString, characterData, ("characterData"));
  return characterData;
}

}  // namespace

MutationRecord* MutationRecord::createChildList(Node* target,
                                                StaticNodeList* added,
                                                StaticNodeList* removed,
                                                Node* previousSibling,
                                                Node* nextSibling) {
  return new ChildListRecord(target, added, removed, previousSibling,
                             nextSibling);
}

MutationRecord* MutationRecord::createAttributes(Node* target,
                                                 const QualifiedName& name,
                                                 const AtomicString& oldValue) {
  return new AttributesRecord(target, name, oldValue);
}

MutationRecord* MutationRecord::createCharacterData(Node* target,
                                                    const String& oldValue) {
  return new CharacterDataRecord(target, oldValue);
}

MutationRecord* MutationRecord::createWithNullOldValue(MutationRecord* record) {
  return new MutationRecordWithNullOldValue(record);
}

MutationRecord::~MutationRecord() {}

}  // namespace blink