fix(wait-for): Don't queue microtasks after condition is met

[eps1lon]

What:

Fixes integration with of @testing-library/react@alpha in React Spectrum when using React 18.

Why:

Otherwise context restoration in unstable_advanceTimersWrapper becomes unpredictable leading to fixes like d375ff3 (#2526) that seemingly have nothing to do with the test/implemenation but magically fix tests.

The implementation change fixed

it('should handle when a non drop target element is added', async () => {
      let setShowInput2;
      let Test = () => {
        let [showInput2, _setShowInput2] = React.useState(false);
        setShowInput2 = _setShowInput2;
        return (<>
          <Draggable />
          <input />
          <Droppable />
          {showInput2 &&
            <input />
          }
        </>);
      };

      let tree = render(<Test />);

      let draggable = tree.getByText('Drag me');

      expect(tree.getAllByRole('textbox')).toHaveLength(1);

      fireEvent.focus(draggable);
      fireEvent.click(draggable);
      act(() => jest.runAllTimers());

      expect(() => tree.getAllByRole('textbox')).toThrow();

      act(() => setShowInput2(true));
      // MutationObserver is async
      await waitFor(() => expect(() => tree.getAllByRole('textbox')).toThrow());

      fireEvent.click(draggable);
      expect(tree.getAllByRole('textbox')).toHaveLength(2);
    });

-- https://github.com/adobe/react-spectrum/blob/8dc33dcdab3bb41518daf023c18939e844e843eb/packages/%40react-aria/dnd/test/dnd.test.js#L2072-L2105

How:

Exit the loop once the callback no longer throws instead of unconditionally queuing another microtask.

This may be an issue with how @testing-library/react uses unstable_advanceTimersWrapper.
Alternatively, we could flush microtasks before we check the callback. But this was intentionall though we don't have any test/repro for that at the moment /cc @kentcdodds

Checklist:

• Documentation added to the
  docs site
• Tests
• [ ] TypeScript definitions updated
• Ready to be merged
  

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[codecov]

Codecov Report

Merging #1073 (2b8da94) into main (2866544) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##              main     #1073   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           25        25           
  Lines          952       954    +2     
  Branches       311       312    +1     
=========================================
+ Hits           952       954    +2     

Flag	Coverage Δ
node-12	100.00% <100.00%> (ø)
node-14	100.00% <100.00%> (ø)
node-16.9.1	100.00% <100.00%> (ø)

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Impacted Files	Coverage Δ
src/wait-for.js	100.00% <100.00%> (ø)

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[eps1lon]

Was no-act without the change. We had the following schedule-resolution order:

Without this change:

1. start asyncWrapper
2. start unstable_advanceTimersWrapper
3. leave asyncWrapper
4. leave unstable_advanceTimersWrapper

With this change:

1. start asyncWrapper
2. start unstable_advanceTimersWrapper
3. leave unstable_advanceTimersWrapper
4. leave asyncWrapper

In other words, before asyncWrapper and unstable_advanceTimersWrapper were interleaved instead of nested.

[kentcdodds]

I didn't realize unstable_advanceTimersWrapper was a thing 😅 The test looks a bit complicated, but I understand why so that's fine. This looks good to me 👍

[eps1lon]

I didn't realize unstable_advanceTimersWrapper was a thing sweat_smile

Added in #1022 because we can't indiscriminantly wrap waitFor in act anymore in React 18.

I hope the linked issues/threads etc make it possible to follow why we need all of this. Though it's quite involved. Please hit me over the head after React 18 is stable that I should write up why we needed all the changes. Right now I'm too lazy considering all of this may change.

The test looks a bit complicated, but I understand why so that's fine. This looks good to me +1

Yeah the test is way too involved for my liking as well. I'm just glad we have some automatic verification though. I wouldn't be surprised if it turns out that the usage of unstable_advanceTimersWrapper is just wrong in the test. But at least this way we have accountability.

[eps1lon]

RE: #667 (comment)

Bookshelf app tests path with this PR (#1073).
But they fail if I revert #667 so let's stick with the approach in this PR.

Ultimately we should add a test that illustrates what's happening in the bookshelf app. Hopefully we can refactor our implementation to fix all tests but keep the code simpler.

[kentcdodds]

Sounds good to me 👍

[github-actions]

🎉 This PR is included in version 8.11.1 🎉

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