diff --git a/extensions/typescript-language-features/src/tsServer/bufferSyncSupport.ts b/extensions/typescript-language-features/src/tsServer/bufferSyncSupport.ts
index a38b67f0a02..0f6218e938e 100644
--- a/extensions/typescript-language-features/src/tsServer/bufferSyncSupport.ts
+++ b/extensions/typescript-language-features/src/tsServer/bufferSyncSupport.ts
@@ -16,17 +16,6 @@ import { ResourceMap } from '../utils/resourceMap';
 import { API } from './api';
 import type * as Proto from './protocol/protocol';
 
-const enum BufferLanguage {
-	TypeScript = 1,
-	JavaScript = 2,
-}
-
-const enum BufferState {
-	Initial = 1,
-	Open = 2,
-	Closed = 2,
-}
-
 type ScriptKind = 'TS' | 'TSX' | 'JS' | 'JSX';
 
 function mode2ScriptKind(mode: string): ScriptKind | undefined {
@@ -39,6 +28,8 @@ function mode2ScriptKind(mode: string): ScriptKind | undefined {
 	return undefined;
 }
 
+const enum BufferState { Initial, Open, Closed }
+
 const enum BufferOperationType { Close, Open, Change }
 
 class CloseOperation {
@@ -236,17 +227,8 @@ class SyncedBuffer {
 		return this.document.lineCount;
 	}
 
-	public get language(): BufferLanguage {
-		switch (this.document.languageId) {
-			case languageModeIds.javascript:
-			case languageModeIds.javascriptreact:
-				return BufferLanguage.JavaScript;
-
-			case languageModeIds.typescript:
-			case languageModeIds.typescriptreact:
-			default:
-				return BufferLanguage.TypeScript;
-		}
+	public get languageId(): string {
+		return this.document.languageId;
 	}
 
 	/**
@@ -462,8 +444,9 @@ export default class BufferSyncSupport extends Disposable {
 
 	private readonly client: ITypeScriptServiceClient;
 
-	private _validateJavaScript: boolean = true;
-	private _validateTypeScript: boolean = true;
+	private _validateJavaScript = true;
+	private _validateTypeScript = true;
+
 	private readonly modeIds: Set<string>;
 	private readonly syncedBuffers: SyncedBufferMap;
 	private readonly pendingDiagnostics: PendingDiagnostics;
@@ -755,11 +738,13 @@ export default class BufferSyncSupport extends Disposable {
 			return false;
 		}
 
-		switch (buffer.language) {
-			case BufferLanguage.JavaScript:
+		switch (buffer.languageId) {
+			case languageModeIds.javascript:
+			case languageModeIds.javascriptreact:
 				return this._validateJavaScript;
 
-			case BufferLanguage.TypeScript:
+			case languageModeIds.typescript:
+			case languageModeIds.typescriptreact:
 			default:
 				return this._validateTypeScript;
 		}