Add SCI_GETUNDOSEQUENCE to determine whether an undo sequence is active and its

nesting depth.

7 files changed, 18 insertions, 0 deletions

diff --git a/src/CellBuffer.cxx b/src/CellBuffer.cxx
index b0b9d9c39..4985517e0 100644
--- a/src/CellBuffer.cxx
+++ b/src/CellBuffer.cxx
@@ -1070,6 +1070,10 @@ void CellBuffer::EndUndoAction() noexcept {
 	uh->EndUndoAction();
 }
 
+int CellBuffer::UndoSequenceDepth() const noexcept {
+	return uh->UndoSequenceDepth();
+}
+
 void CellBuffer::AddUndoAction(Sci::Position token, bool mayCoalesce) {
 	bool startSequence = false;
 	uh->AppendAction(ActionType::container, token, nullptr, 0, startSequence, mayCoalesce);
diff --git a/src/CellBuffer.h b/src/CellBuffer.h
index 3a72601a6..d5d9a0467 100644
--- a/src/CellBuffer.h
+++ b/src/CellBuffer.h
@@ -166,6 +166,7 @@ public:
 	bool IsCollectingUndo() const noexcept;
 	void BeginUndoAction(bool mayCoalesce=false) noexcept;
 	void EndUndoAction() noexcept;
+	int UndoSequenceDepth() const noexcept;
 	void AddUndoAction(Sci::Position token, bool mayCoalesce);
 	void DeleteUndoHistory() noexcept;
 
diff --git a/src/Document.cxx b/src/Document.cxx
index 3ae8964ba..88b876ebd 100644
--- a/src/Document.cxx
+++ b/src/Document.cxx
@@ -1543,6 +1543,10 @@ Sci::Position Document::Redo() {
 	return newPos;
 }
 
+int Document::UndoSequenceDepth() const noexcept {
+	return cb.UndoSequenceDepth();
+}
+
 void Document::DelChar(Sci::Position pos) {
 	DeleteChars(pos, LenChar(pos));
 }
diff --git a/src/Document.h b/src/Document.h
index efb1ae6d6..fa1c3fe42 100644
--- a/src/Document.h
+++ b/src/Document.h
@@ -397,6 +397,7 @@ public:
 	bool IsCollectingUndo() const noexcept { return cb.IsCollectingUndo(); }
 	void BeginUndoAction(bool coalesceWithPrior=false) noexcept { cb.BeginUndoAction(coalesceWithPrior); }
 	void EndUndoAction() noexcept { cb.EndUndoAction(); }
+	int UndoSequenceDepth() const noexcept;
 	void AddUndoAction(Sci::Position token, bool mayCoalesce) { cb.AddUndoAction(token, mayCoalesce); }
 	void SetSavePoint();
 	bool IsSavePoint() const noexcept { return cb.IsSavePoint(); }
diff --git a/src/Editor.cxx b/src/Editor.cxx
index 390c83898..0561b42f8 100644
--- a/src/Editor.cxx
+++ b/src/Editor.cxx
@@ -6636,6 +6636,9 @@ sptr_t Editor::WndProc(Message iMessage, uptr_t wParam, sptr_t lParam) {
 		pdoc->EndUndoAction();
 		return 0;
 
+	case Message::GetUndoSequence:
+		return pdoc->UndoSequenceDepth();
+
 	case Message::GetUndoActions:
 		return pdoc->UndoActions();
 
diff --git a/src/UndoHistory.cxx b/src/UndoHistory.cxx
index c4b241103..c0d7ba5f2 100644
--- a/src/UndoHistory.cxx
+++ b/src/UndoHistory.cxx
@@ -350,6 +350,10 @@ void UndoHistory::EndUndoAction() noexcept {
 	}
 }
 
+int UndoHistory::UndoSequenceDepth() const noexcept {
+	return undoSequenceDepth;
+}
+
 void UndoHistory::DropUndoSequence() noexcept {
 	undoSequenceDepth = 0;
 }
diff --git a/src/UndoHistory.h b/src/UndoHistory.h
index 8cde395ae..be639c541 100644
--- a/src/UndoHistory.h
+++ b/src/UndoHistory.h
@@ -101,6 +101,7 @@ public:
 
 	void BeginUndoAction(bool mayCoalesce=false) noexcept;
 	void EndUndoAction() noexcept;
+	int UndoSequenceDepth() const noexcept;
 	void DropUndoSequence() noexcept;
 	void DeleteUndoHistory() noexcept;