/**
     * @return Generator<Promise<Phpactor\LanguageServer\Core\Rpc\ResponseMessage|null>>
     */
    public function testReturnsNullIfMessageIsANotification(): Generator
    {
            $dispatcher = $this->createRunner([
                new ClosureHandler('foobar', function (): void {
                })
            ]);

            $response = yield $dispatcher->dispatch(
                new NotificationMessage('foobar', [])
            );

            self::assertNull($response);
    }