Fixes #110141: Do not push undo stack elements for a no-op EOL change

extensions/vscode-api-tests/src/singlefolder-tests/workspace.test.ts

@@ -1014,4 +1014,38 @@ suite('vscode API - workspace', () => {
 		}
 
 	});
+
+	test('issue #110141 - TextEdit.setEndOfLine applies an edit and invalidates redo stack even when no change is made', async () => {
+		const file = await createRandomFile('hello\nworld');
+
+		const document = await vscode.workspace.openTextDocument(file);
+		await vscode.window.showTextDocument(document);
+
+		// apply edit
+		{
+			const we = new vscode.WorkspaceEdit();
+			we.insert(file, new vscode.Position(0, 5), '2');
+			await vscode.workspace.applyEdit(we);
+		}
+
+		// check the document
+		{
+			assert.equal(document.getText(), 'hello2\nworld');
+			assert.equal(document.isDirty, true);
+		}
+
+		// apply no-op edit
+		{
+			const we = new vscode.WorkspaceEdit();
+			we.set(file, [vscode.TextEdit.setEndOfLine(vscode.EndOfLine.LF)]);
+			await vscode.workspace.applyEdit(we);
+		}
+
+		// undo
+		{
+			await vscode.commands.executeCommand('undo');
+			assert.equal(document.getText(), 'hello\nworld');
+			assert.equal(document.isDirty, false);
+		}
+	});
 });

src/vs/editor/common/model.ts

@@ -695,6 +695,11 @@ export interface ITextModel {
 	 */
 	getEOL(): string;
 
+	/**
+	 * Get the end of line sequence predominantly used in the text buffer.
+	 */
+	getEndOfLineSequence(): EndOfLineSequence;
+
 	/**
 	 * Get the minimum legal column for line at `lineNumber`
 	 */

src/vs/editor/common/model/textModel.ts

@@ -830,6 +830,15 @@ export class TextModel extends Disposable implements model.ITextModel {
 		return this._buffer.getEOL();
 	}
 
+	public getEndOfLineSequence(): model.EndOfLineSequence {
+		this._assertNotDisposed();
+		return (
+			this._buffer.getEOL() === '\n'
+				? model.EndOfLineSequence.LF
+				: model.EndOfLineSequence.CRLF
+		);
+	}
+
 	public getLineMinColumn(lineNumber: number): number {
 		this._assertNotDisposed();
 		return 1;

src/vs/monaco.d.ts

@@ -1685,6 +1685,10 @@ declare namespace monaco.editor {
 		 * @return EOL char sequence (e.g.: '\n' or '\r\n').
 		 */
 		getEOL(): string;
+		/**
+		 * Get the end of line sequence predominantly used in the text buffer.
+		 */
+		getEndOfLineSequence(): EndOfLineSequence;
 		/**
 		 * Get the minimum legal column for line at `lineNumber`
 		 */

src/vs/workbench/contrib/bulkEdit/browser/bulkTextEdits.ts

@@ -39,6 +39,18 @@ class ModelEditTask implements IDisposable {
 		this._modelReference.dispose();
 	}
 
+	isNoOp() {
+		if (this._edits.length > 0) {
+			// contains textual edits
+			return false;
+		}
+		if (this._newEol !== undefined && this._newEol !== this.model.getEndOfLineSequence()) {
+			// contains an eol change that is a real change
+			return false;
+		}
+		return true;
+	}
+
 	addEdit(resourceEdit: ResourceTextEdit): void {
 		this._expectedModelVersionId = resourceEdit.versionId;
 		const { textEdit } = resourceEdit;
@@ -219,10 +231,12 @@ export class BulkTextEdits {
 			if (tasks.length === 1) {
 				// This edit touches a single model => keep things simple
 				const task = tasks[0];
-				const singleModelEditStackElement = new SingleModelEditStackElement(task.model, task.getBeforeCursorState());
-				this._undoRedoService.pushElement(singleModelEditStackElement, this._undoRedoGroup);
-				task.apply();
-				singleModelEditStackElement.close();
+				if (!task.isNoOp()) {
+					const singleModelEditStackElement = new SingleModelEditStackElement(task.model, task.getBeforeCursorState());
+					this._undoRedoService.pushElement(singleModelEditStackElement, this._undoRedoGroup);
+					task.apply();
+					singleModelEditStackElement.close();
+				}
 				this._progress.report(undefined);
 			} else {
 				// prepare multi model undo element