const fn = <T>(p: T) => p;describe('top-level', () => {  describe('when passed a number', () => {    const value = 1;    it('returns a number', () => {      expect(typeof fn(value)).toBe('number');    });    it('returns the passed value', () => {      expect(fn(value)).toBe(value);    });  });  describe('when passed a boolean', () => {    const value = true;    it('returns a boolean', () => {      expect(typeof fn(value)).toBe('boolean');    });    it('returns the passed value', () => {      expect(fn(value)).toBe(value);    });  });  describe('when passed a string', () => {    const value = "hello world";    it('returns a string', () => {      expect(typeof fn(value)).toBe('string');    });    it('returns the passed value', () => {      expect(fn(value)).toBe(value);    });  });});