testing: improve labeling in peek for accessibility

src/vs/editor/browser/widget/diffEditorWidget.ts

@@ -1151,6 +1151,9 @@ export class DiffEditorWidget extends Disposable implements editorBrowser.IDiffE
 		} else {
 			result.wordWrapOverride1 = this._diffWordWrap;
 		}
+		if (options.originalAriaLabel) {
+			result.ariaLabel = options.originalAriaLabel;
+		}
 		result.readOnly = !this._originalIsEditable;
 		result.extraEditorClassName = 'original-in-monaco-diff-editor';
 		return {
@@ -1164,6 +1167,10 @@ export class DiffEditorWidget extends Disposable implements editorBrowser.IDiffE
 
 	private _adjustOptionsForRightHandSide(options: Readonly<editorBrowser.IDiffEditorConstructionOptions>): editorBrowser.IEditorConstructionOptions {
 		const result = this._adjustOptionsForSubEditor(options);
+		if (options.modifiedAriaLabel) {
+			result.ariaLabel = options.modifiedAriaLabel;
+		}
+
 		result.wordWrapOverride1 = this._diffWordWrap;
 		result.revealHorizontalRightPadding = EditorOptions.revealHorizontalRightPadding.defaultValue + DiffEditorWidget.ENTIRE_DIFF_OVERVIEW_WIDTH;
 		result.scrollbar!.verticalHasArrows = false;

src/vs/editor/common/config/editorOptions.ts

@@ -690,6 +690,14 @@ export interface IDiffEditorOptions extends IEditorOptions {
 	 * Control the wrapping of the diff editor.
 	 */
 	diffWordWrap?: 'off' | 'on' | 'inherit';
+	/**
+	 * Aria label for original editor.
+	 */
+	originalAriaLabel?: string;
+	/**
+	 * Aria label for modifed editor.
+	 */
+	modifiedAriaLabel?: string;
 }
 
 //#endregion

src/vs/monaco.d.ts

@@ -3247,6 +3247,14 @@ declare namespace monaco.editor {
 		 * Control the wrapping of the diff editor.
 		 */
 		diffWordWrap?: 'off' | 'on' | 'inherit';
+		/**
+		 * Aria label for original editor.
+		 */
+		originalAriaLabel?: string;
+		/**
+		 * Aria label for modifed editor.
+		 */
+		modifiedAriaLabel?: string;
 	}
 
 	/**

src/vs/workbench/contrib/testing/browser/testingOutputPeek.ts

@@ -4,6 +4,7 @@
  *--------------------------------------------------------------------------------------------*/
 
 import * as dom from 'vs/base/browser/dom';
+import { alert } from 'vs/base/browser/ui/aria/aria';
 import { Codicon } from 'vs/base/common/codicons';
 import { Color } from 'vs/base/common/color';
 import { KeyCode } from 'vs/base/common/keyCodes';
@@ -203,6 +204,7 @@ export class TestingOutputPeekController extends Disposable implements IEditorCo
 			this.peek.value!.create();
 		}
 
+		alert(message.message.toString());
 		this.peek.value!.setModel(dto);
 	}
 
@@ -321,6 +323,8 @@ const diffEditorOptions: IDiffEditorOptions = {
 	renderOverviewRuler: false,
 	ignoreTrimWhitespace: false,
 	renderSideBySide: true,
+	originalAriaLabel: localize('testingOutputExpected', 'Expected result'),
+	modifiedAriaLabel: localize('testingOutputActual', 'Actual result'),
 };
 
 class TestingDiffOutputPeek extends TestingOutputPeek {