JavaScript Intellisense doesn't detect types of properties defined in async constructors

JavaScript Intellisense doesn't detect types of properties defined in async constructors

Summary

A popular asynchronous constructor pattern in JavaScript is using an async IIFE in the constructor which returns this at the end. E.g.

constructor() {
	return (async () => {
		this.#x = 42;
		this.y = 42;

		return this;
	})();
}

However, VSCode Intellisense does not infer the types for properties defined in such a constructor.

Steps to reproduce

1. Open a blank JavaScript, and paste in the following code:

class Class1 {
	#x;
	y;
	constructor() {
		this.#x = 42;
		this.y = 42;
	}
}
class Class2 {
	#x;
	y;
	constructor() {
		return (async () => {
			this.#x = 42;
			this.y = 42;

			return this;
		})();
	}
}

2. Hover over y in Class1 and observe the tooltip: (property) Class1.y: number
3. Hover over y in Class2 and observe the tooltip: (property) Class2.y: any

Does this issue occur when all extensions are disabled?: Yes

• VS Code Version: 1.97.0
• OS Version: Windows 11

提供された Class1 と Class2 の例を使って VS Code で問題を再現し、拡張機能を無効にした場合のホバー型と比較してください。TypeScript language-service における非同期コンストラクター向けの JavaScript IntelliSense の処理を追跡し、その後リグレッションテストのカバレッジを追加してください。Class2.y が Class1.y と同様に number と推論されれば完了です。