React + Jest + Enzyme form onSubmit test fails unless I use timeout

I have a React form wrapper that takes an onSubmit prop of type function, and I want to test if it's being called with the correct form values. If I check it right away, it fails, but if I put the check behind a 100ms timeout, it passes.

So it appears as if there needs to be some kind of processing time for the functions to be executed, but the timeout is so janky...

Example

test('onSubmit function is called with correct form values', () => {
    const defaults = {
        email: 'superadmin@gmail.com',
        password: 'soSoSecret!'
    };
    const submitFunction = jest.fn();
    const wrapper = mount(<LoginForm onSubmit={submitFunction} />);

    // input form values
    wrapper
        .find('input[name="email"]')
        .simulate('change', { target: { value: defaults.email } });
    wrapper
        .find('input[name="password"]')
        .simulate('change', { target: { value: defaults.password } });

    expect(submitFunction.mock.calls.length).toBe(0);
    wrapper.find('form button[type="submit"]').simulate('click');

    // if I test right away, it fails, but if I set timeout for 100ms, it passes
    // does the form take time to process and the function be called????

    jest.useFakeTimers();
    setTimeout(() => {
        expect(submitFunction.mock.calls.length).toBe(1);
        const args = submitFunction.mock.calls[0][0];
        expect(args).toEqual(defaults);
    }, 100);
});

Is it possible to write a test like this without a timeout? Seems like an issue to me.

Thanks for reading! :D