editor/libeditor/InsertTextTransaction.h
author Nathan Froyd <froydnj@gmail.com>
Fri, 12 Aug 2016 22:43:49 -0400
changeset 400339 e3608df9fe09f509a8fe62be0cd6743151e4f7a3
parent 386002 b97cb7c9d1e34abea935f5a1827a88471531afa9
child 437525 02a8bebe6c89ceb023bd598b77b40c5817cd4007
permissions -rw-r--r--
Bug 1294537 - introduce a non-null-checking placement operator new; r=sunfish,nbp The default placement operator new is defined to always require that its result be null-checked. A sufficiently smart compiler can remove this check, but not all compilers are sufficiently smart. Better to have a custom placement operator new that will remove null checks in a way defined by the standard.

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef InsertTextTransaction_h
#define InsertTextTransaction_h

#include "mozilla/EditTransactionBase.h"  // base class
#include "nsCycleCollectionParticipant.h" // various macros
#include "nsID.h"                       // NS_DECLARE_STATIC_IID_ACCESSOR
#include "nsISupportsImpl.h"            // NS_DECL_ISUPPORTS_INHERITED
#include "nsString.h"                   // nsString members
#include "nscore.h"                     // NS_IMETHOD, nsAString

class nsITransaction;

#define NS_INSERTTEXTTXN_IID \
{ 0x8c9ad77f, 0x22a7, 0x4d01, \
  { 0xb1, 0x59, 0x8a, 0x0f, 0xdb, 0x1d, 0x08, 0xe9 } }

namespace mozilla {

class EditorBase;
namespace dom {
class Text;
} // namespace dom

/**
 * A transaction that inserts text into a content node.
 */
class InsertTextTransaction final : public EditTransactionBase
{
public:
  NS_DECLARE_STATIC_IID_ACCESSOR(NS_INSERTTEXTTXN_IID)

  /**
   * @param aElement        The text content node.
   * @param aOffset         The location in aElement to do the insertion.
   * @param aString         The new text to insert.
   * @param aPresShell      Used to get and set the selection.
   */
  InsertTextTransaction(dom::Text& aTextNode, uint32_t aOffset,
                        const nsAString& aString, EditorBase& aEditorBase);

  NS_DECL_ISUPPORTS_INHERITED
  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(InsertTextTransaction,
                                           EditTransactionBase)

  NS_DECL_EDITTRANSACTIONBASE

  NS_IMETHOD Merge(nsITransaction* aTransaction, bool* aDidMerge) override;

  /**
   * Return the string data associated with this transaction.
   */
  void GetData(nsString& aResult);

private:
  virtual ~InsertTextTransaction();

  // Return true if aOtherTransaction immediately follows this transaction.
  bool IsSequentialInsert(InsertTextTransaction& aOtherTrasaction);

  // The Text node to operate upon.
  RefPtr<dom::Text> mTextNode;

  // The offset into mTextNode where the insertion is to take place.
  uint32_t mOffset;

  // The text to insert into mTextNode at mOffset.
  nsString mStringToInsert;

  // The editor, which we'll need to get the selection.
  EditorBase& mEditorBase;
};

NS_DEFINE_STATIC_IID_ACCESSOR(InsertTextTransaction, NS_INSERTTEXTTXN_IID)

} // namespace mozilla

#endif // #ifndef InsertTextTransaction_h