How do I change the history on a a mounted component for testing?

Whn going through the docs for react router, I came across a utility component that helps track page changes (for what ever purpose needed). This is the component:

export const PageTracker = (props: PageTrackerProps) => {
  const { callback } = props;

  let location = useLocation();
  React.useEffect(() => {
    callback(location);
  }, [location, callback]);

  return null;
};

I want to add a test to it to make sure that the callback is indeed called on location change, but can't figure it out.

describe("<PageTracker />", () => {
  let wrapper;
  let history;

  test("The callback is called when route changes", () => {
    const mockCallback = jest.fn();

    wrapper = mount(
      <MemoryRouter initialEntries={["/"]}>
        <PageTracker callback={mockCallback} />
      </MemoryRouter>
    );

    history = wrapper.instance().history;
    expect(mockCallback).toBeCalledTimes(1);

    history.push("/new-url");

    expect(mockCallback).toBeCalledTimes(2);
  });
});

But it fails here: expect(mockCallback).toBeCalledTimes(2); saying it still was only called once.

I've tried changing the test a bit (just moving things around, not much of a change):

describe("<PageTracker />", () => {

  test("The callback is called when route changes", () => {
    const mockCallback = jest.fn();

    const wrapper = mount(
      <MemoryRouter initialEntries={["/"]}>
        <PageTracker callback={mockCallback} />
      </MemoryRouter>
    );

    const history = wrapper.instance().history;
    expect(mockCallback).toBeCalledTimes(1);

    history.push("/new-url");

    expect(mockCallback).toBeCalledTimes(2);
  });
});

And now I get an rror on this line const history = wrapper.instance().history; saying const history = wrapper.instance().history;.

I don't have much experience with jest/enzyme, would appreciate a point in the right direction.