fix: useTransition hook works correctly with a function argument. (#2287)

[Roman178]

Why

#2287.
The useTransition hook doesn't work correctly if we pass a function as an argument.

What

If we pass a function to the hook, a ref variable will be created, an instance of SpringRef.
Then, as stated in the comment, if the ref exists, the update is postponed until the ref's start method is called. By calling the ctrl update method, we simply put another item in the queue. Perhaps I didn’t fully understand it, but I didn’t see calling the start method on an existing ref that flushes the queue.

Calling the ref's start method in useIsomorphicLayoutEffect solves the problem.

Checklist

• Documentation updated
• Demo added
• Ready to be merged

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[Roman178]

Hello @joshuaellis
Just a friendly reminder. I would appreciate it if you would take a moment to review my PR.

[joshuaellis]

Hey sorry for the late reply.

The useTransition hook when provided with a config function isn't designed to play its animations automatically. Instead you receive a second item in the returned array which is the API for you to trigger the animation when desired.

If you want it to automatically play, just pass an object.

Let me know if I've misunderstood something about the issue you're trying to fix 😊