test("basic functionality", () => { expect(void "").toBeUndefined(); expect(void "foo").toBeUndefined(); expect(void 1).toBeUndefined(); expect(void 42).toBeUndefined(); expect(void true).toBeUndefined(); expect(void false).toBeUndefined(); expect(void null).toBeUndefined(); expect(void undefined).toBeUndefined(); expect(void function () {}).toBeUndefined(); expect(void (() => {})).toBeUndefined(); expect(void (() => "hello friends")()).toBeUndefined(); expect((() => void "hello friends")()).toBeUndefined(); });