Handle language pack uninstallation

src/vs/workbench/contrib/extensions/browser/extensionsWorkbenchService.ts

@@ -1510,7 +1510,8 @@ export class ExtensionsWorkbenchService extends Disposable implements IExtension
 		if (locale === language) {
 			return;
 		}
-		return this.localeService.setLocale({ id: locale, galleryExtension: extension.gallery, extensionId: extension.identifier.id, label: extension.displayName });
+		const localizedLanguageName = extension.gallery?.properties?.localizedLanguages?.[0];
+		return this.localeService.setLocale({ id: locale, galleryExtension: extension.gallery, extensionId: extension.identifier.id, label: localizedLanguageName ?? extension.displayName });
 	}
 
 	setEnablement(extensions: IExtension | IExtension[], enablementState: EnablementState): Promise<void> {

src/vs/workbench/contrib/localization/browser/localeService.ts

@@ -20,7 +20,7 @@ export class WebLocaleService implements ILocaleService {
 		@IProductService private readonly productService: IProductService
 	) { }
 
-	async setLocale(languagePackItem: ILanguagePackItem): Promise<void> {
+	async setLocale(languagePackItem: ILanguagePackItem, _skipDialog = false): Promise<void> {
 		const locale = languagePackItem.id;
 		if (locale === Language.value() || (!locale && Language.value() === navigator.language)) {
 			return;

src/vs/workbench/contrib/localization/common/locale.ts

@@ -10,6 +10,6 @@ export const ILocaleService = createDecorator<ILocaleService>('localizationServi
 
 export interface ILocaleService {
 	readonly _serviceBrand: undefined;
-	setLocale(languagePackItem: ILanguagePackItem): Promise<void>;
+	setLocale(languagePackItem: ILanguagePackItem, skipDialog?: boolean): Promise<void>;
 	clearLocalePreference(): Promise<void>;
 }

src/vs/workbench/contrib/localization/electron-sandbox/localeService.ts

@@ -75,7 +75,7 @@ export class NativeLocaleService implements ILocaleService {
 		return true;
 	}
 
-	async setLocale(languagePackItem: ILanguagePackItem): Promise<void> {
+	async setLocale(languagePackItem: ILanguagePackItem, skipDialog = false): Promise<void> {
 		const locale = languagePackItem.id;
 		if (locale === Language.value() || (!locale && Language.isDefaultVariant())) {
 			return;
@@ -108,7 +108,7 @@ export class NativeLocaleService implements ILocaleService {
 				);
 			}
 
-			if (await this.writeLocaleValue(locale)) {
+			if (await this.writeLocaleValue(locale) && !skipDialog) {
 				await this.showRestartDialog(languagePackItem.label);
 			}
 		} catch (err) {
@@ -127,15 +127,15 @@ export class NativeLocaleService implements ILocaleService {
 		}
 	}
 
-	private async showRestartDialog(languageName: string) {
+	private async showRestartDialog(languageName: string): Promise<void> {
 		const restartDialog = await this.dialogService.confirm({
 			type: 'info',
-			message: localize('restartDisplayLanguageMessage', "To change the display language, {0} needs to restart", this.productService.nameLong),
+			message: localize('restartDisplayLanguageMessage1', "Restart {0} to switch to {1}?", this.productService.nameLong, languageName),
 			detail: localize(
-				'restartDisplayLanguageDetail',
-				"Press the restart button to restart {0} and set the display language to {1}.",
-				this.productService.nameLong,
-				languageName
+				'restartDisplayLanguageDetail1',
+				"To change the display language to {0}, {1} needs to restart.",
+				languageName,
+				this.productService.nameLong
 			),
 			primaryButton: localize({ key: 'restart', comment: ['&& denotes a mnemonic character'] }, "&&Restart"),
 		});

src/vs/workbench/contrib/localization/electron-sandbox/localization.contribution.ts

@@ -10,11 +10,9 @@ import { Disposable } from 'vs/base/common/lifecycle';
 import { ExtensionsRegistry } from 'vs/workbench/services/extensions/common/extensionsRegistry';
 import { LifecyclePhase } from 'vs/workbench/services/lifecycle/common/lifecycle';
 import * as platform from 'vs/base/common/platform';
-import { IExtensionManagementService, IExtensionGalleryService, IGalleryExtension, InstallOperation, InstallExtensionResult } from 'vs/platform/extensionManagement/common/extensionManagement';
+import { IExtensionManagementService, IExtensionGalleryService, InstallOperation, ILocalExtension, InstallExtensionResult, DidUninstallExtensionEvent } from 'vs/platform/extensionManagement/common/extensionManagement';
 import { INotificationService, NeverShowAgainScope } from 'vs/platform/notification/common/notification';
 import Severity from 'vs/base/common/severity';
-import { IJSONEditingService } from 'vs/workbench/services/configuration/common/jsonEditing';
-import { IEnvironmentService } from 'vs/platform/environment/common/environment';
 import { IHostService } from 'vs/workbench/services/host/browser/host';
 import { IStorageService, StorageScope, StorageTarget } from 'vs/platform/storage/common/storage';
 import { VIEWLET_ID as EXTENSIONS_VIEWLET_ID, IExtensionsViewPaneContainer } from 'vs/workbench/contrib/extensions/common/extensions';
@@ -28,6 +26,7 @@ import { ClearDisplayLanguageAction, ConfigureDisplayLanguageAction } from 'vs/w
 import { InstantiationType, registerSingleton } from 'vs/platform/instantiation/common/extensions';
 import { ILocaleService } from 'vs/workbench/contrib/localization/common/locale';
 import { NativeLocaleService } from 'vs/workbench/contrib/localization/electron-sandbox/localeService';
+import { IProductService } from 'vs/platform/product/common/productService';
 
 registerSingleton(ILocaleService, NativeLocaleService, InstantiationType.Delayed);
 
@@ -40,8 +39,8 @@ const LANGUAGEPACK_SUGGESTION_IGNORE_STORAGE_KEY = 'extensionsAssistant/language
 export class LocalizationWorkbenchContribution extends Disposable implements IWorkbenchContribution {
 	constructor(
 		@INotificationService private readonly notificationService: INotificationService,
-		@IJSONEditingService private readonly jsonEditingService: IJSONEditingService,
-		@IEnvironmentService private readonly environmentService: IEnvironmentService,
+		@ILocaleService private readonly localeService: ILocaleService,
+		@IProductService private readonly productService: IProductService,
 		@IHostService private readonly hostService: IHostService,
 		@IStorageService private readonly storageService: IStorageService,
 		@IExtensionManagementService private readonly extensionManagementService: IExtensionManagementService,
@@ -53,37 +52,62 @@ export class LocalizationWorkbenchContribution extends Disposable implements IWo
 
 		this.checkAndInstall();
 		this._register(this.extensionManagementService.onDidInstallExtensions(e => this.onDidInstallExtensions(e)));
+		this._register(this.extensionManagementService.onDidUninstallExtension(e => this.onDidUninstallExtension(e)));
 	}
 
-	private onDidInstallExtensions(results: readonly InstallExtensionResult[]): void {
-		for (const e of results) {
-			if (e.operation !== InstallOperation.Install || !e.local?.manifest?.contributes?.localizations?.length) {
-				continue;
-			}
-			const languageId = e.local.manifest.contributes.localizations[0].languageId;
-			if (platform.language === languageId) {
-				continue;
+	private async onDidInstallExtensions(results: readonly InstallExtensionResult[]): Promise<void> {
+		for (const result of results) {
+			if (result.operation === InstallOperation.Install && result.local) {
+				await this.onDidInstallExtension(result.local, !!result.context?.extensionsSync);
 			}
+		}
+
+	}
 
+	private async onDidInstallExtension(localExtension: ILocalExtension, fromSettingsSync: boolean): Promise<void> {
+		const localization = localExtension.manifest.contributes?.localizations?.[0];
+		if (!localization || platform.language === localization.languageId) {
+			return;
+		}
+		const { languageId, languageName } = localization;
+
+		if (fromSettingsSync) {
 			this.notificationService.prompt(
 				Severity.Info,
-				localize('updateLocale', "Would you like to change VS Code's UI language to {0} and restart?", e.local.manifest.contributes.localizations[0].languageName || e.local.manifest.contributes.localizations[0].languageId),
+				localize('updateLocale', "Would you like to change {0}'s display language to {1} and restart?", this.productService.nameLong, languageName || languageId),
 				[{
 					label: localize('changeAndRestart', "Change Language and Restart"),
 					run: async () => {
-						try {
-							await this.jsonEditingService.write(this.environmentService.argvResource, [{ path: ['locale'], value: languageId }], true);
-							await this.hostService.restart();
-						} catch (e) {
-							this.notificationService.error(e);
-						}
+						await this.localeService.setLocale({
+							id: languageId,
+							label: languageName ?? languageId,
+							extensionId: localExtension.identifier.id,
+							// If settings sync installs the language pack, then we would have just shown the notification so no
+							// need to show the dialog.
+						}, true);
 					}
 				}],
 				{
 					sticky: true,
 					neverShowAgain: { id: 'langugage.update.donotask', isSecondary: true, scope: NeverShowAgainScope.APPLICATION }
 				}
 			);
+			return;
+		}
+
+		await this.localeService.setLocale({
+			id: languageId,
+			label: languageName ?? languageId,
+			extensionId: localExtension.identifier.id,
+		});
+	}
+
+	private async onDidUninstallExtension(_event: DidUninstallExtensionEvent): Promise<void> {
+		if (!await this.isLocaleInstalled(platform.language)) {
+			this.localeService.setLocale({
+				id: 'en',
+				label: 'English'
+			});
 		}
 	}
 
@@ -172,8 +196,12 @@ export class LocalizationWorkbenchContribution extends Disposable implements IWo
 							label: translations['installAndRestart'],
 							run: async () => {
 								logUserReaction('installAndRestart');
-								await this.installExtension(extensionToInstall!);
-								await this.jsonEditingService.write(this.environmentService.argvResource, [{ path: ['locale'], value: locale }], true);
+								await this.localeService.setLocale({
+									id: locale,
+									label: languageName,
+									extensionId: extensionToInstall?.identifier.id,
+									// The user will be prompted if they want to install the language pack before this.
+								}, true);
 								await this.hostService.restart();
 							}
 						};
@@ -213,14 +241,6 @@ export class LocalizationWorkbenchContribution extends Disposable implements IWo
 		return installed.some(i => !!i.manifest.contributes?.localizations?.length
 			&& i.manifest.contributes.localizations.some(l => locale.startsWith(l.languageId.toLowerCase())));
 	}
-
-	private installExtension(extension: IGalleryExtension): Promise<void> {
-		return this.paneCompositeService.openPaneComposite(EXTENSIONS_VIEWLET_ID, ViewContainerLocation.Sidebar)
-			.then(viewlet => viewlet?.getViewPaneContainer() as IExtensionsViewPaneContainer)
-			.then(viewlet => viewlet.search(`@id:${extension.identifier.id}`))
-			.then(() => this.extensionManagementService.installFromGallery(extension))
-			.then(() => undefined, err => this.notificationService.error(err));
-	}
 }
 
 const workbenchRegistry = Registry.as<IWorkbenchContributionsRegistry>(WorkbenchExtensions.Workbench);