Fix notebook insertFinalNewline behavior (microsoft#194442)

fix typing newline bug

Author: Yoyokrazy

src/vs/workbench/contrib/notebook/browser/contrib/saveParticipants/saveParticipants.ts

@@ -45,8 +45,7 @@ class FormatOnSaveParticipant implements IStoredFileWorkingCopySaveParticipant {
 		@ITextModelService private readonly textModelService: ITextModelService,
 		@IBulkEditService private readonly bulkEditService: IBulkEditService,
 		@IConfigurationService private readonly configurationService: IConfigurationService,
-	) {
-	}
+	) { }
 
 	async participate(workingCopy: IStoredFileWorkingCopy<IStoredFileWorkingCopyModel>, context: { reason: SaveReason }, progress: IProgress<IProgressStep>, token: CancellationToken): Promise<void> {
 		if (!workingCopy.model || !(workingCopy.model instanceof NotebookFileWorkingCopyModel)) {
@@ -178,7 +177,7 @@ class TrimFinalNewLinesParticipant implements IStoredFileWorkingCopySaveParticip
 
 	async participate(workingCopy: IStoredFileWorkingCopy<IStoredFileWorkingCopyModel>, context: { reason: SaveReason }, progress: IProgress<IProgressStep>, _token: CancellationToken): Promise<void> {
 		if (this.configurationService.getValue<boolean>('files.trimFinalNewlines')) {
-			this.doTrimFinalNewLines(workingCopy, context.reason === SaveReason.AUTO, progress);
+			await this.doTrimFinalNewLines(workingCopy, context.reason === SaveReason.AUTO, progress);
 		}
 	}
 
@@ -250,22 +249,30 @@ class FinalNewLineParticipant implements IStoredFileWorkingCopySaveParticipant {
 	constructor(
 		@IConfigurationService private readonly configurationService: IConfigurationService,
 		@IBulkEditService private readonly bulkEditService: IBulkEditService,
+		@IEditorService private readonly editorService: IEditorService,
 	) { }
 
 	async participate(workingCopy: IStoredFileWorkingCopy<IStoredFileWorkingCopyModel>, context: { reason: SaveReason }, progress: IProgress<IProgressStep>, _token: CancellationToken): Promise<void> {
 		if (this.configurationService.getValue('files.insertFinalNewline')) {
-			this.doInsertFinalNewLine(workingCopy, context, progress);
+			await this.doInsertFinalNewLine(workingCopy, context.reason === SaveReason.AUTO, progress);
 		}
 	}
 
-	private async doInsertFinalNewLine(workingCopy: IStoredFileWorkingCopy<IStoredFileWorkingCopyModel>, context: { reason: SaveReason }, progress: IProgress<IProgressStep>): Promise<void> {
+	private async doInsertFinalNewLine(workingCopy: IStoredFileWorkingCopy<IStoredFileWorkingCopyModel>, isAutoSaved: boolean, progress: IProgress<IProgressStep>): Promise<void> {
 		if (!workingCopy.model || !(workingCopy.model instanceof NotebookFileWorkingCopyModel)) {
 			return;
 		}
 
 		const disposable = new DisposableStore();
 		const notebook = workingCopy.model.notebookModel;
 
+		// get initial cursor positions
+		const activeCellEditor = getActiveCellCodeEditor(this.editorService);
+		let selections;
+		if (activeCellEditor) {
+			selections = activeCellEditor.getSelections() ?? [];
+		}
+
 		try {
 			const allCellEdits = await Promise.all(notebook.cells.map(async (cell) => {
 				if (cell.cellKind !== CellKind.Code) {
@@ -285,6 +292,10 @@ class FinalNewLineParticipant implements IStoredFileWorkingCopySaveParticipant {
 			const filteredEdits = allCellEdits.filter(edit => edit !== undefined) as ResourceEdit[];
 			await this.bulkEditService.apply(filteredEdits, { label: localize('insertFinalNewLine', "Insert Final New Line"), code: 'undoredo.insertFinalNewLine' });
 
+			// set cursor back to initial position after inserting final new line
+			if (activeCellEditor && selections) {
+				activeCellEditor.setSelections(selections);
+			}
 		} finally {
 			progress.report({ increment: 100 });
 			disposable.dispose();