1 files changed, 71 insertions, 0 deletions
diff --git a/editor/libeditor/SplitNodeTransaction.h b/editor/libeditor/SplitNodeTransaction.h
new file mode 100644
index 000000000..36119518b
--- /dev/null
+++ b/editor/libeditor/SplitNodeTransaction.h
@@ -0,0 +1,71 @@
+/* -*- 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 SplitNodeTransaction_h
+#define SplitNodeTransaction_h
+
+#include "mozilla/EditTransactionBase.h" // for EditTxn, etc.
+#include "nsCOMPtr.h"                   // for nsCOMPtr
+#include "nsCycleCollectionParticipant.h"
+#include "nsISupportsImpl.h"            // for NS_DECL_ISUPPORTS_INHERITED
+#include "nscore.h"                     // for NS_IMETHOD
+
+class nsIContent;
+class nsINode;
+
+namespace mozilla {
+
+class EditorBase;
+
+/**
+ * A transaction that splits a node into two identical nodes, with the children
+ * divided between the new nodes.
+ */
+class SplitNodeTransaction final : public EditTransactionBase
+{
+public:
+  /**
+   * @param aEditorBase The provider of core editing operations
+   * @param aNode       The node to split
+   * @param aOffset     The location within aNode to do the split.  aOffset may
+   *                    refer to children of aNode, or content of aNode.  The
+   *                    left node will have child|content 0..aOffset-1.
+   */
+  SplitNodeTransaction(EditorBase& aEditorBase, nsIContent& aNode,
+                       int32_t aOffset);
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(SplitNodeTransaction,
+                                           EditTransactionBase)
+
+  NS_DECL_EDITTRANSACTIONBASE
+
+  NS_IMETHOD RedoTransaction() override;
+
+  nsIContent* GetNewNode();
+
+protected:
+  virtual ~SplitNodeTransaction();
+
+  EditorBase& mEditorBase;
+
+  // The node to operate upon.
+  nsCOMPtr<nsIContent> mExistingRightNode;
+
+  // The offset into mExistingRightNode where its children are split.  mOffset
+  // is the index of the first child in the right node.  -1 means the new node
+  // gets no children.
+  int32_t mOffset;
+
+  // The node we create when splitting mExistingRightNode.
+  nsCOMPtr<nsIContent> mNewLeftNode;
+
+  // The parent shared by mExistingRightNode and mNewLeftNode.
+  nsCOMPtr<nsINode> mParent;
+};
+
+} // namespace mozilla
+
+#endif // #ifndef SplitNodeTransaction_h