fix: ensure SvelteDate cached methods have correct reactive context

[Rich-Harris]

alternative to #14512 — instead of using the nearest parent effect, we use whichever reaction was active when the instance was created

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Playground

pnpm add https://pkg.pr.new/svelte@14525

[Rich-Harris]

preview: https://svelte-dev-git-preview-svelte-14525-svelte.vercel.app/

this is an automated message

[simeydotme]

Not sure if anyone will see this, but this change has caused a rather severe performance bug in my library, not sure if this affects anyone else but it could be considered breaking as the REPL basically dies if the console is closed (infinite loop, it seems like)

I'm sure there must be something I'm doing that is unorthodox but from version 3.0.0, up until version 5.5.2 there was no such issue. If anyone knows how to resolve, please let me know ... otherwise if I figure it out I'll drop the answer back in here. 🙏

[paoloricciuti]

Could it be something in 5.5.1?

#14529

If i have to guess this is the culprit: #14192

you are probably doing a lot of this and so it's constantly logging the warning?

[simeydotme]

Could it be something in 5.5.1?

#14529

If i have to guess this is the culprit: #14192

you are probably doing a lot of this and so it's constantly logging the warning?

ah, it could be!
I saw this, also, which appears adjacent; #14643

I think based on your comment and the commit you shared, it is possibly because I have a $: statement being updated by a spring-store result 🤔 ... (imagine I'm not the only one) but after thinking about it, perhaps that's a code smell and I should try to refactor that to use the subscribe method for reassignment instead (possibly with a rAF() debouncer.

Thanks @paoloricciuti this gives me a nice direction to follow up 🙏