Fixes #46208: Recover selection from markers when the undo/redo stack lacks selection information

src/vs/editor/common/controller/cursor.ts

@@ -361,7 +361,7 @@ export class Cursor extends viewEvents.ViewEventEmitter implements ICursors {
 
 	private _interpretCommandResult(cursorState: Selection[]): void {
 		if (!cursorState || cursorState.length === 0) {
-			return;
+			cursorState = this._cursors.readSelectionFromMarkers();
 		}
 
 		this._columnSelectData = null;

src/vs/editor/common/services/modelServiceImpl.ts

@@ -13,7 +13,6 @@ import URI from 'vs/base/common/uri';
 import { TPromise } from 'vs/base/common/winjs.base';
 import { IMarker, IMarkerService, MarkerSeverity } from 'vs/platform/markers/common/markers';
 import { Range } from 'vs/editor/common/core/range';
-import { Selection } from 'vs/editor/common/core/selection';
 import { TextModel, createTextBuffer } from 'vs/editor/common/model/textModel';
 import { IMode, LanguageIdentifier } from 'vs/editor/common/modes';
 import { IModelService } from 'vs/editor/common/services/modelService';
@@ -398,9 +397,9 @@ export class ModelServiceImpl implements IModelService {
 		// Otherwise find a diff between the values and update model
 		model.setEOL(textBuffer.getEOL() === '\r\n' ? EndOfLineSequence.CRLF : EndOfLineSequence.LF);
 		model.pushEditOperations(
-			[new Selection(1, 1, 1, 1)],
+			[],
 			ModelServiceImpl._computeEdits(model, textBuffer),
-			(inverseEditOperations: IIdentifiedSingleEditOperation[]) => [new Selection(1, 1, 1, 1)]
+			(inverseEditOperations: IIdentifiedSingleEditOperation[]) => []
 		);
 	}
 
@@ -451,7 +450,7 @@ export class ModelServiceImpl implements IModelService {
 			newRange = new Range(1, 1, textBufferLineCount, 1 + textBuffer.getLineLength(textBufferLineCount));
 		}
 
-		return [EditOperation.replace(oldRange, textBuffer.getValueInRange(newRange, EndOfLinePreference.TextDefined))];
+		return [EditOperation.replaceMove(oldRange, textBuffer.getValueInRange(newRange, EndOfLinePreference.TextDefined))];
 	}
 
 	public createModel(value: string | ITextBufferFactory, modeOrPromise: TPromise<IMode> | IMode, resource: URI, isForSimpleWidget: boolean = false): ITextModel {

src/vs/editor/test/browser/controller/cursor.test.ts

@@ -1219,6 +1219,64 @@ suite('Editor Controller - Regression tests', () => {
 		model.dispose();
 	});
 
+	test('issue #46208: Allow empty selections in the undo/redo stack', () => {
+		let model = TextModel.createFromString('');
+
+		withTestCodeEditor(null, { model: model }, (editor, cursor) => {
+			cursorCommand(cursor, H.Type, { text: 'Hello' }, 'keyboard');
+			cursorCommand(cursor, H.Type, { text: ' ' }, 'keyboard');
+			cursorCommand(cursor, H.Type, { text: 'world' }, 'keyboard');
+			cursorCommand(cursor, H.Type, { text: ' ' }, 'keyboard');
+			assert.equal(model.getLineContent(1), 'Hello world ');
+			assertCursor(cursor, new Position(1, 13));
+
+			moveLeft(cursor);
+			moveRight(cursor);
+
+			model.pushEditOperations([], [EditOperation.replaceMove(new Range(1, 12, 1, 13), '')], () => []);
+			assert.equal(model.getLineContent(1), 'Hello world');
+			assertCursor(cursor, new Position(1, 12));
+
+			cursorCommand(cursor, H.Undo, {});
+			assert.equal(model.getLineContent(1), 'Hello world ');
+			assertCursor(cursor, new Position(1, 13));
+
+			cursorCommand(cursor, H.Undo, {});
+			assert.equal(model.getLineContent(1), 'Hello world');
+			assertCursor(cursor, new Position(1, 12));
+
+			cursorCommand(cursor, H.Undo, {});
+			assert.equal(model.getLineContent(1), 'Hello');
+			assertCursor(cursor, new Position(1, 6));
+
+			cursorCommand(cursor, H.Undo, {});
+			assert.equal(model.getLineContent(1), '');
+			assertCursor(cursor, new Position(1, 1));
+
+			cursorCommand(cursor, H.Redo, {});
+			assert.equal(model.getLineContent(1), 'Hello');
+			assertCursor(cursor, new Position(1, 6));
+
+			cursorCommand(cursor, H.Redo, {});
+			assert.equal(model.getLineContent(1), 'Hello world');
+			assertCursor(cursor, new Position(1, 12));
+
+			cursorCommand(cursor, H.Redo, {});
+			assert.equal(model.getLineContent(1), 'Hello world ');
+			assertCursor(cursor, new Position(1, 13));
+
+			cursorCommand(cursor, H.Redo, {});
+			assert.equal(model.getLineContent(1), 'Hello world');
+			assertCursor(cursor, new Position(1, 12));
+
+			cursorCommand(cursor, H.Redo, {});
+			assert.equal(model.getLineContent(1), 'Hello world');
+			assertCursor(cursor, new Position(1, 12));
+		});
+
+		model.dispose();
+	});
+
 	test('bug #16815:Shift+Tab doesn\'t go back to tabstop', () => {
 		let mode = new OnEnterMode(IndentAction.IndentOutdent);
 		let model = TextModel.createFromString(

src/vs/workbench/api/electron-browser/mainThreadSaveParticipant.ts

@@ -50,7 +50,7 @@ class TrimWhitespaceParticipant implements ISaveParticipantParticipant {
 	}
 
 	private doTrimTrailingWhitespace(model: ITextModel, isAutoSaved: boolean): void {
-		let prevSelection: Selection[] = [new Selection(1, 1, 1, 1)];
+		let prevSelection: Selection[] = [];
 		const cursors: Position[] = [];
 
 		let editor = findEditor(model, this.codeEditorService);
@@ -114,7 +114,7 @@ export class FinalNewLineParticipant implements ISaveParticipantParticipant {
 			return;
 		}
 
-		let prevSelection: Selection[] = [new Selection(1, 1, 1, 1)];
+		let prevSelection: Selection[] = [];
 		const editor = findEditor(model, this.codeEditorService);
 		if (editor) {
 			prevSelection = editor.getSelections();
@@ -151,7 +151,7 @@ export class TrimFinalNewLinesParticipant implements ISaveParticipantParticipant
 			return;
 		}
 
-		let prevSelection: Selection[] = [new Selection(1, 1, 1, 1)];
+		let prevSelection: Selection[] = [];
 		const editor = findEditor(model, this.codeEditorService);
 		if (editor) {
 			prevSelection = editor.getSelections();