Add vertical scroll position into undo selection history unconditionally.

3 files changed, 21 insertions, 14 deletions

diff --git a/src/EditModel.cxx b/src/EditModel.cxx
index 5263de38b..e12aab38e 100644
--- a/src/EditModel.cxx
+++ b/src/EditModel.cxx
@@ -67,18 +67,18 @@ void ModelState::ForgetSelectionForUndo() noexcept {
 	historyForUndo.indexCurrent = -1;
 }
 
-void ModelState::RememberSelectionOntoStack(int index) {
+void ModelState::RememberSelectionOntoStack(int index, Sci::Line topLine) {
 	if ((historyForUndo.indexCurrent >= 0) && (index == historyForUndo.indexCurrent + 1)) {
 		// Don't overwrite initial selection save if most recent action was coalesced
-		historyForUndo.stack[index] = historyForUndo.ssCurrent;
+		historyForUndo.stack[index] = { historyForUndo.ssCurrent, topLine };
 	}
 }
 
-void ModelState::RememberSelectionForRedoOntoStack(int index, const Selection &sel) {
-	historyForRedo.stack[index] = sel.ToString();
+void ModelState::RememberSelectionForRedoOntoStack(int index, const Selection &sel, Sci::Line topLine) {
+	historyForRedo.stack[index] = { sel.ToString(), topLine };
 }
 
-std::string_view ModelState::SelectionFromStack(int index, UndoRedo history) const {
+SelectionWithScroll ModelState::SelectionFromStack(int index, UndoRedo history) const {
 	const SelectionHistory &sh = history == UndoRedo::undo ? historyForUndo : historyForRedo;
 	const SelectionStack::const_iterator it = sh.stack.find(index);
 	if (it != sh.stack.end()) {
diff --git a/src/EditModel.h b/src/EditModel.h
index 1c4823b2e..dcaf99613 100644
--- a/src/EditModel.h
+++ b/src/EditModel.h
@@ -24,7 +24,13 @@ public:
 enum class UndoRedo { undo, redo };
 
 // Selection stack is sparse so use a map
-using SelectionStack = std::map<int, std::string>;
+
+struct SelectionWithScroll {
+	std::string selection;
+	Sci::Line topLine = 0;
+};
+
+using SelectionStack = std::map<int, SelectionWithScroll>;
 
 struct SelectionHistory {
 	int indexCurrent = 0;
@@ -37,9 +43,9 @@ struct ModelState : ViewState {
 	SelectionHistory historyForRedo;
 	void RememberSelectionForUndo(int index, const Selection &sel);
 	void ForgetSelectionForUndo() noexcept;
-	void RememberSelectionOntoStack(int index);
-	void RememberSelectionForRedoOntoStack(int index, const Selection &sel);
-	std::string_view SelectionFromStack(int index, UndoRedo history) const;
+	void RememberSelectionOntoStack(int index, Sci::Line topLine);
+	void RememberSelectionForRedoOntoStack(int index, const Selection &sel, Sci::Line topLine);
+	SelectionWithScroll SelectionFromStack(int index, UndoRedo history) const;
 	virtual void TruncateUndo(int index) final;
 };
 
diff --git a/src/Editor.cxx b/src/Editor.cxx
index 77d2eb175..283edff8f 100644
--- a/src/Editor.cxx
+++ b/src/Editor.cxx
@@ -951,7 +951,7 @@ void Editor::RememberSelectionOntoStack(int index) {
 		if (!pdoc->AfterUndoSequenceStart()) {
 			// Don't remember selections inside a grouped sequence as can only
 			// unto or redo to the start and end of the group.
-			modelState->RememberSelectionOntoStack(index);
+			modelState->RememberSelectionOntoStack(index, topLine);
 		}
 	}
 }
@@ -960,7 +960,7 @@ void Editor::RememberCurrentSelectionForRedoOntoStack() {
 	if (needRedoRemembered && (pdoc->UndoSequenceDepth() == 0)) {
 		EnsureModelState();
 		if (modelState) {
-			modelState->RememberSelectionForRedoOntoStack(pdoc->UndoCurrent(), sel);
+			modelState->RememberSelectionForRedoOntoStack(pdoc->UndoCurrent(), sel, topLine);
 			needRedoRemembered = false;
 		}
 	}
@@ -2412,9 +2412,10 @@ void Editor::RestoreSelection(Sci::Position newPos, UndoRedo history) {
 	if ((undoSelectionHistoryOption == UndoSelectionHistoryOption::Enabled) && modelState) {
 		// Undo wants the element after the current as it just undid it
 		const int index = pdoc->UndoCurrent() + (history == UndoRedo::undo ? 1 : 0);
-		const std::string_view ss = modelState->SelectionFromStack(index, history);
-		if (!ss.empty()) {
-			sel = Selection(ss);
+		const SelectionWithScroll selAndLine = modelState->SelectionFromStack(index, history);
+		if (!selAndLine.selection.empty()) {
+			ScrollTo(selAndLine.topLine);
+			sel = Selection(selAndLine.selection);
 			if (sel.IsRectangular()) {
 				const size_t mainForRectangular = sel.Main();
 				// Reconstitute ranges from rectangular range