Inherited class binding on components inside transition-group is not updated

[jonaskuske]

Version

3.0.0-alpha.4

Reproduction link

https://codepen.io/21stCenturyJonas/pen/ZEYdOBg?editors=1010

Steps to reproduce

1. Render list of components inside <transiton-group> using v-for
2. Add class binding that relies on index to component
3. Update the list so indices change

What is expected?

The class binding updates as the rendered list changes.
If the class binding evaluated index === 0 and the index is not 0 anymore, the binding should evaluate to false and the class should be removed.

What is actually happening?

The class is not removed, even though the expression in the class binding now evaluates to false.

[dsfx3d]

Is this issue open for PRs?

[jonaskuske]

Well I don't have the time to work on this myself at the moment, and since there's been no activity from others, I'd assume so?

Prior triage would be appreciated though @yyx990803 :)

[jonaskuske]

@yyx990803 There's a regression in the latest alpha, the repro from above (https://codepen.io/21stCenturyJonas/pen/ZEYdOBg, updated it to use alpha.12) is failing again.
It works when going back to alpha.11.

[yyx990803]

This is fixed in a6e2b10