Svelte 5: exit transition variable is not reactive

[Thiagolino8]

Describe the bug

When a element is mounted the transition that is in the out: directive becomes fixed, even if the given value is a state that changes until the element is unmounted

Reproduction

v4
v5

Logs

No response

System Info

App.svelte (Svelte v5.0.0-next.19)

Severity

blocking an upgrade

[longnguyen2004]

It does work for me though?

[trueadm]

@Thiagolino8 I'm struggling to see the issue here. I've even put the duration down to 10 seconds and I can't spot any differences between the REPLs.

[brunnerh]

Repro steps are:

• Observe current out transition: scale
• Click show button
• Change out transition by clicking on scale
• Observe current out transition is now fade
• Click hide button

=> Element is removed using scale rather than fade

[Thiagolino8]

@trueadm, The problem is not how the transition is being executed, but rather which
The difference is that in V5 the exit transition cannot be changed after the element is mounted
The steps for reproduction are as @brunnerh detailed