onRest is not called for immediate animations

[jacobrask]

I would expect either neither onStart or onRest, or both, be called with an immediate animation. Instead only onStart is called. This causes some issues in our application because I want to render the content slightly differently (lower quality images) if we are currently in an active animation. If I setState({ isAnimating: true }) in onStart it will not be reset if the animation is was in immediate mode.

<Spring
  immediate
  from={{ height: 10 }}
  to={{ height: 100 }}
  onStart={() => console.log("start")}
  onRest={() => console.log("rest")}
>
  {({ height }) => <div style={{ background: "hotpink", height }} />}
</Spring>

[drcmda]

That's generally a hard call, theres some async stuff that relies on a started spring to conclude, for instance keyframes or now useChain. If a spring could just "do nothing" when started, promises would potentionally never finish. Do you need it for something particular?

[jacobrask]

I am sliding between really large images and I get better performance if I can replace them with lower quality thumbnails while the animation is active. When you first go to a link to a specific slide I want it to be immediate and don't scroll through all previous ones.