Re-render renders component from scratch when used in separate tests

[anzorb]

It appears that using re-render inside separate tests does not update props and instead re-renders the component from scratch. Is this by design?

See https://codesandbox.io/s/testing-libraryreact-re-render-issue-o1osd for a complete example

export const Bla = ({ hooo }) => {
  const id = useRef(0);

  useEffect(() => {
    id.current++;
    console.log("id:", id.current);
  }, [hooo]);

  return <div>{hooo}</div>;
};

describe("bla", () => {
  let instance;
  beforeAll(() => {
    instance = render(<Bla hooo={3} />);
  });

  it("works when in one test", () => {
    instance.rerender(<Bla hooo={4} />);
    instance.rerender(<Bla hooo={5} />);
    instance.rerender(<Bla hooo={6} />);
    // output id: 1, 2, 3, 4
    expect(true).toBe(true);
  });

  it("doesn't work 1", () => {
    instance.rerender(<Bla hooo={7} />);
    // output id: 1
    expect(true).toBe(true);
  });

  it("doesn't work 2", () => {
    instance.rerender(<Bla hooo={8} />);
    // output id: 1
    expect(true).toBe(true);
  });
});

[eps1lon]

Thank you for opening this issue and providing a reproduction.

This is expected. We automatically clean up between each test as of #430. It explains how you can disabled this behavior though we do not recommend it.

[kentcdodds]

Here's more info on why: https://kentcdodds.com/blog/avoid-nesting-when-youre-testing