alert screen reader users with changes in watch variables (#221847)

src/vs/workbench/contrib/debug/browser/debug.contribution.ts

@@ -60,6 +60,7 @@ import { launchSchemaId } from 'vs/workbench/services/configuration/common/confi
 import { LifecyclePhase } from 'vs/workbench/services/lifecycle/common/lifecycle';
 import './debugSettingMigration';
 import { DebugAccessibilityHelp } from 'vs/workbench/contrib/debug/browser/debugAccessibilityHelp';
+import { DebugWatchAccessibilityAnnouncer } from 'vs/workbench/contrib/debug/common/debugAccessibilityAnnouncer';
 import { ReplAccessibilityAnnouncer } from 'vs/workbench/contrib/debug/common/replAccessibilityAnnouncer';
 
 const debugCategory = nls.localize('debugCategory', "Debug");
@@ -646,4 +647,5 @@ configurationRegistry.registerConfiguration({
 
 AccessibleViewRegistry.register(new DebugAccessibleView());
 AccessibleViewRegistry.register(new DebugAccessibilityHelp());
+registerWorkbenchContribution2(DebugWatchAccessibilityAnnouncer.ID, DebugWatchAccessibilityAnnouncer, WorkbenchPhase.AfterRestored);
 registerWorkbenchContribution2(ReplAccessibilityAnnouncer.ID, ReplAccessibilityAnnouncer, WorkbenchPhase.AfterRestored);

src/vs/workbench/contrib/debug/common/debug.ts

@@ -743,7 +743,14 @@ export interface IDebugModel extends ITreeElement {
 	getBreakpointModes(forBreakpointType: 'source' | 'exception' | 'data' | 'instruction'): DebugProtocol.BreakpointMode[];
 	onDidChangeBreakpoints: Event<IBreakpointsChangeEvent | undefined>;
 	onDidChangeCallStack: Event<void>;
+	/**
+	 * The expression has been added, removed, or repositioned.
+	 */
 	onDidChangeWatchExpressions: Event<IExpression | undefined>;
+	/**
+	 * The expression's value has changed.
+	 */
+	onDidChangeWatchExpressionValue: Event<IExpression | undefined>;
 
 	fetchCallstack(thread: IThread, levels?: number): Promise<void>;
 }

src/vs/workbench/contrib/debug/common/debugAccessibilityAnnouncer.ts

@@ -0,0 +1,30 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { IDebugService } from 'vs/workbench/contrib/debug/common/debug';
+import { Disposable } from 'vs/base/common/lifecycle';
+import { IWorkbenchContribution } from 'vs/workbench/common/contributions';
+import { ILogService } from 'vs/platform/log/common/log';
+import { IAccessibilityService } from 'vs/platform/accessibility/common/accessibility';
+
+export class DebugWatchAccessibilityAnnouncer extends Disposable implements IWorkbenchContribution {
+	static ID = 'workbench.contrib.debugWatchAccessibilityAnnouncer';
+	constructor(
+		@IDebugService _debugService: IDebugService,
+		@ILogService _logService: ILogService,
+		@IAccessibilityService _accessibilityService: IAccessibilityService
+	) {
+		super();
+		this._register(_debugService.getModel().onDidChangeWatchExpressionValue((e) => {
+			if (!e || e.value === 'not available') {
+				return;
+			}
+
+			// TODO: get user feedback, perhaps setting to configure verbosity + whether value, name, neither, or both are announced
+			_accessibilityService.alert(`${e.name} = ${e.value}`);
+			_logService.trace(`debugAccessibilityAnnouncerValueChanged ${e.name} ${e.value}`);
+		}));
+	}
+}

src/vs/workbench/contrib/debug/common/debugModel.ts

@@ -298,6 +298,9 @@ export class Expression extends ExpressionContainer implements IExpression {
 
 	public available: boolean;
 
+	private readonly _onDidChangeValue = new Emitter<IExpression>();
+	public readonly onDidChangeValue: Event<IExpression> = this._onDidChangeValue.event;
+
 	constructor(public name: string, id = generateUuid()) {
 		super(undefined, undefined, 0, id);
 		this.available = false;
@@ -310,6 +313,9 @@ export class Expression extends ExpressionContainer implements IExpression {
 
 	async evaluate(session: IDebugSession | undefined, stackFrame: IStackFrame | undefined, context: string, keepLazyVars?: boolean, location?: IDebugEvaluatePosition): Promise<void> {
 		this.available = await this.evaluateExpression(this.name, session, stackFrame, context, keepLazyVars, location);
+		if (this.valueChanged) {
+			this._onDidChangeValue.fire(this);
+		}
 	}
 
 	override toString(): string {
@@ -1403,6 +1409,7 @@ export class DebugModel extends Disposable implements IDebugModel {
 	private readonly _onDidChangeBreakpoints = this._register(new Emitter<IBreakpointsChangeEvent | undefined>());
 	private readonly _onDidChangeCallStack = this._register(new Emitter<void>());
 	private readonly _onDidChangeWatchExpressions = this._register(new Emitter<IExpression | undefined>());
+	private readonly _onDidChangeWatchExpressionValue = this._register(new Emitter<IExpression | undefined>());
 	private readonly _breakpointModes = new Map<string, IBreakpointModeInternal>();
 	private breakpoints!: Breakpoint[];
 	private functionBreakpoints!: FunctionBreakpoint[];
@@ -1497,6 +1504,10 @@ export class DebugModel extends Disposable implements IDebugModel {
 		return this._onDidChangeWatchExpressions.event;
 	}
 
+	get onDidChangeWatchExpressionValue(): Event<IExpression | undefined> {
+		return this._onDidChangeWatchExpressionValue.event;
+	}
+
 	rawUpdate(data: IRawModelUpdate): void {
 		const session = this.sessions.find(p => p.getId() === data.sessionId);
 		if (session) {
@@ -2003,6 +2014,7 @@ export class DebugModel extends Disposable implements IDebugModel {
 
 	addWatchExpression(name?: string): IExpression {
 		const we = new Expression(name || '');
+		this._register(we.onDidChangeValue((e) => this._onDidChangeWatchExpressionValue.fire(e)));
 		this.watchExpressions.push(we);
 		this._onDidChangeWatchExpressions.fire(we);