Use vscode watches for tsserver

extensions/typescript-language-features/src/tsServer/protocol/protocol.const.ts

@@ -88,6 +88,9 @@ export enum EventName {
 	surveyReady = 'surveyReady',
 	projectLoadingStart = 'projectLoadingStart',
 	projectLoadingFinish = 'projectLoadingFinish',
+	createFileWatcher = 'createFileWatcher',
+	createDirectoryWatcher = 'createDirectoryWatcher',
+	closeFileWatcher = 'closeFileWatcher',
 }
 
 export enum OrganizeImportsMode {

extensions/typescript-language-features/src/tsServer/spawner.ts

@@ -270,6 +270,7 @@ export class TypeScriptServerSpawner {
 		args.push('--locale', TypeScriptServerSpawner.getTsLocale(configuration));
 
 		args.push('--noGetErrOnBackgroundUpdate');
+		args.push('--canUseWatchEvents'); // TODO check ts version
 
 		args.push('--validateDefaultNpmLocation');
 

extensions/typescript-language-features/src/typescriptService.ts

@@ -85,6 +85,7 @@ interface NoResponseTsServerRequests {
 	'compilerOptionsForInferredProjects': [Proto.SetCompilerOptionsForInferredProjectsArgs, null];
 	'reloadProjects': [null, null];
 	'configurePlugin': [Proto.ConfigurePluginRequest, Proto.ConfigurePluginResponse];
+	'watchChange': [Proto.Request, null];
 }
 
 interface AsyncTsServerRequests {

extensions/typescript-language-features/src/typescriptServiceClient.ts

@@ -128,6 +128,8 @@ export default class TypeScriptServiceClient extends Disposable implements IType
 	private readonly versionProvider: ITypeScriptVersionProvider;
 	private readonly processFactory: TsServerProcessFactory;
 
+	private readonly watches = new Map<number, vscode.FileSystemWatcher>();
+
 	constructor(
 		private readonly context: vscode.ExtensionContext,
 		onCaseInsenitiveFileSystem: boolean,
@@ -973,6 +975,45 @@ export default class TypeScriptServiceClient extends Disposable implements IType
 			case EventName.projectLoadingFinish:
 				this.loadingIndicator.finishedLoadingProject((event as Proto.ProjectLoadingFinishEvent).body.projectName);
 				break;
+
+			case EventName.createDirectoryWatcher:
+				this.createFileSystemWatcher(event.body.id, new vscode.RelativePattern(vscode.Uri.file(event.body.path), event.body.recursive ? '**' : '*'));
+				break;
+
+			case EventName.createFileWatcher:
+				this.createFileSystemWatcher(event.body.id, event.body.path);
+				break;
+
+			case EventName.closeFileWatcher:
+				this.closeFileSystemWatcher(event.body.id);
+				break;
+		}
+	}
+
+	private createFileSystemWatcher(
+		id: number,
+		pattern: vscode.GlobPattern,
+	) {
+		const watcher = vscode.workspace.createFileSystemWatcher(pattern);
+		watcher.onDidChange(changeFile =>
+			this.executeWithoutWaitingForResponse('watchChange', { id, path: changeFile.fsPath, eventType: 'update' })
+		);
+		watcher.onDidCreate(createFile =>
+			this.executeWithoutWaitingForResponse('watchChange', { id, path: createFile.fsPath, eventType: 'create' })
+		);
+		watcher.onDidDelete(deletedFile =>
+			this.executeWithoutWaitingForResponse('watchChange', { id, path: deletedFile.fsPath, eventType: 'delete' })
+		);
+		this.watches.set(id, watcher);
+	}
+
+	private closeFileSystemWatcher(
+		id: number,
+	) {
+		const existing = this.watches.get(id);
+		if (existing) {
+			existing.dispose();
+			this.watches.delete(id);
 		}
 	}