toBeInstanceOf(Exception::class); expect(new Exception())->not->toBeInstanceOf(RuntimeException::class); }); test('failures', function () { expect(new Exception())->toBeInstanceOf(RuntimeException::class); })->throws(ExpectationFailedException::class); test('not failures', function () { expect(new Exception())->not->toBeInstanceOf(Exception::class); })->throws(ExpectationFailedException::class);