Added completion entry for @ts-expect-error directive (#92093)

* Added completion entry for @ts-expect-error directive

* Limited to relevant TS versions

* You know what, it's more complicated, I'll just go with everything vs 3.9

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

@@ -6,6 +6,7 @@
 import * as vscode from 'vscode';
 import * as nls from 'vscode-nls';
 import { ITypeScriptServiceClient } from '../typescriptService';
+import API from '../utils/api';
 
 const localize = nls.loadMessageBundle();
 
@@ -33,11 +34,26 @@ const directives: Directive[] = [
 	}
 ];
 
+const directives390: Directive[] = [
+	...directives,
+	{
+		value: '@ts-expect-error',
+		description: localize(
+			'ts-expect-error',
+			"Suppresses @ts-check errors on the next line of a file, expecting at least one to exist.")
+	}
+];
+
 class DirectiveCommentCompletionProvider implements vscode.CompletionItemProvider {
+	private readonly directives: Directive[];
 
 	constructor(
 		private readonly client: ITypeScriptServiceClient,
-	) { }
+	) {
+		this.directives = client.apiVersion.gte(API.v390)
+			? directives390
+			: directives;
+	}
 
 	public provideCompletionItems(
 		document: vscode.TextDocument,
@@ -53,7 +69,7 @@ class DirectiveCommentCompletionProvider implements vscode.CompletionItemProvide
 		const prefix = line.slice(0, position.character);
 		const match = prefix.match(/^\s*\/\/+\s?(@[a-zA-Z\-]*)?$/);
 		if (match) {
-			return directives.map(directive => {
+			return this.directives.map(directive => {
 				const item = new vscode.CompletionItem(directive.value, vscode.CompletionItemKind.Snippet);
 				item.detail = directive.description;
 				item.range = new vscode.Range(position.line, Math.max(0, position.character - (match[1] ? match[1].length : 0)), position.line, position.character);

extensions/typescript-language-features/src/utils/api.ts

@@ -33,6 +33,7 @@ export default class API {
 	public static readonly v350 = API.fromSimpleString('3.5.0');
 	public static readonly v380 = API.fromSimpleString('3.8.0');
 	public static readonly v381 = API.fromSimpleString('3.8.1');
+	public static readonly v390 = API.fromSimpleString('3.9.0');
 
 	public static fromVersionString(versionString: string): API {
 		let version = semver.valid(versionString);

src/vs/workbench/contrib/welcome/walkThrough/browser/editor/vs_code_editor_walkthrough.ts

@@ -174,7 +174,7 @@ let easy = true;
 easy = 42;
 |||
 
->**Tip:** You can also enable the checks workspace or application wide by adding |"javascript.implicitProjectConfig.checkJs": true| to your workspace or user settings and explicitly ignoring files or lines using |// @ts-nocheck| and |// @ts-ignore|. Check out the docs on [JavaScript in VS Code](https://code.visualstudio.com/docs/languages/javascript) to learn more.
+>**Tip:** You can also enable the checks workspace or application wide by adding |"javascript.implicitProjectConfig.checkJs": true| to your workspace or user settings and explicitly ignoring files or lines using |// @ts-nocheck| and |// @ts-expect-error|. Check out the docs on [JavaScript in VS Code](https://code.visualstudio.com/docs/languages/javascript) to learn more.
 
 
 ## Thanks!