Re-render does not occur synchronously when reactive data is changed in mounted life-cycle hook

[Aaron-Pool]

Version

1.0.0-beta.25

Reproduction link

https://github.com/Aaron-Pool/vue-test-utils-jest-example

Steps to reproduce

1. clone reproduction repo
2. Run yarn
3. run yarn jest

What is expected?

Test should pass, because reactive data changed in the mount component, so the scoped slot function should have been called again on re-render.

What is actually happening?

No re-render occurs, even though the data updates as expected.

---

I assume this has something to do with async vs. sync paradigm that is happening in the test-utils.

It works correctly if I run the test like so:

it('should initialize with dimension data', done => {
  const mockSlot = jest.fn();
  const comp = factory(mockSlot);
  comp.vm.$nextTick(() => {
    expect(mockSlot.mock.calls).toEqual([[{ width: null, height: null }], [{ width: 500, height: 500 }]]);
    done();
  })
});

[pgoshulak]

recognizing this doesn't directly address the synchronicity issue, I found a slightly more elegant temporary workaround is to make the test async, then run as:

const comp = factory(mockSlot)
await comp.vm.$nextTick()
expect(........)

[Aaron-Pool]

@pgoshulak Thanks for the heads up on that 👍 I may implement that as a stopgap as well, to make things cleaner.