Reactivity lost in derived that returns state created outside of derived under certain circumstances

[Leonidaz]

Describe the bug

Derived's reactivity seems to be lost if it returns a state created outside of the derived. This happens only if the derived's returned state is mutated in the component instance block (inside <script>).

Reproduction

Reproduction playground

Steps to replicate:

• click on increment linked button
• click on increment count button
• click on increment linked button
• the reactivity is lost as linked count should have been incremented

removing linked.current++; on line 14 in the <script></script> fixes it

Logs

n/a

System Info

playground

Severity

annoyance

[paoloricciuti]

You shouldn't reassign state in deriveds, the fact that you can do it in untrack is irrelevant imho. Let's keep this open because I feel this is some unowned shenanigan

[Leonidaz]

unowned shenanigan

possibly, not sure if it can fixed without #14784