Avoid creating services in APIs used by the monaco-editor repo itself (microsoft#187881)

Fixes microsoft#169268: Avoid creating services in APIs used by the monaco-editor repo itself

Author: alexdima

src/vs/editor/standalone/browser/standaloneLanguages.ts

@@ -54,16 +54,18 @@ export function getEncodedLanguageId(languageId: string): number {
  * @event
  */
 export function onLanguage(languageId: string, callback: () => void): IDisposable {
-	const languageService = StandaloneServices.get(ILanguageService);
-	const disposable = languageService.onDidRequestRichLanguageFeatures((encounteredLanguageId) => {
-		if (encounteredLanguageId === languageId) {
-			// stop listening
-			disposable.dispose();
-			// invoke actual listener
-			callback();
-		}
+	return StandaloneServices.withServices(() => {
+		const languageService = StandaloneServices.get(ILanguageService);
+		const disposable = languageService.onDidRequestRichLanguageFeatures((encounteredLanguageId) => {
+			if (encounteredLanguageId === languageId) {
+				// stop listening
+				disposable.dispose();
+				// invoke actual listener
+				callback();
+			}
+		});
+		return disposable;
 	});
-	return disposable;
 }
 
 /**
@@ -72,16 +74,18 @@ export function onLanguage(languageId: string, callback: () => void): IDisposabl
  * @event
  */
 export function onLanguageEncountered(languageId: string, callback: () => void): IDisposable {
-	const languageService = StandaloneServices.get(ILanguageService);
-	const disposable = languageService.onDidRequestBasicLanguageFeatures((encounteredLanguageId) => {
-		if (encounteredLanguageId === languageId) {
-			// stop listening
-			disposable.dispose();
-			// invoke actual listener
-			callback();
-		}
+	return StandaloneServices.withServices(() => {
+		const languageService = StandaloneServices.get(ILanguageService);
+		const disposable = languageService.onDidRequestBasicLanguageFeatures((encounteredLanguageId) => {
+			if (encounteredLanguageId === languageId) {
+				// stop listening
+				disposable.dispose();
+				// invoke actual listener
+				callback();
+			}
+		});
+		return disposable;
 	});
-	return disposable;
 }
 
 /**

src/vs/editor/standalone/browser/standaloneServices.ts

@@ -1128,6 +1128,7 @@ export module StandaloneServices {
 	}
 
 	let initialized = false;
+	const onDidInitialize = new Emitter<void>();
 	export function initialize(overrides: IEditorOverrideServices): IInstantiationService {
 		if (initialized) {
 			return instantiationService;
@@ -1163,6 +1164,27 @@ export module StandaloneServices {
 			}
 		}
 
+		onDidInitialize.fire();
+
 		return instantiationService;
 	}
+
+	/**
+	 * Executes callback once services are initialized.
+	 */
+	export function withServices(callback: () => IDisposable): IDisposable {
+		if (initialized) {
+			return callback();
+		}
+
+		const disposable = new DisposableStore();
+
+		const listener = disposable.add(onDidInitialize.event(() => {
+			listener.dispose();
+			disposable.add(callback());
+		}));
+
+		return disposable;
+	}
+
 }