Error: [svelte] reactive_declaration_non_reactive_property

[akb5566]

Hello, I'm using date-picker-svelte@2.15.1. Everything used to work fine. Today I update the package.json of my project, and now wherever the page contains date-picker-svelte, the following error will show on Chrome Dev Console.

AppDatePicker.svelte:24 [svelte] reactive_declaration_non_reactive_property
A $: statement (node_modules/​.pnpm/​date-picker-svelte@2.15.1_svelte@5.10.1/​node_modules/​date-picker-svelte/​dist/​DateInput.svelte:61:0) read reactive state that was not visible to the compiler. Updates to this state will not cause the statement to re-run. The behaviour of this code will change if you migrate it to runes mode

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I think it might be the latest svelte-check@4.1.1 or svelte@5.10.1 that cause the error. Because this error/warning did not exist before I update the packages.

The culprit might be the $: lines in DateInput.svelte

[probablykasper]

It's referring to this line:
https://github.com/probablykasper/date-picker-svelte/blob/master/src/lib/DateInput.svelte#L74

I don't see anything about the error in the link you shared, and the link in the screenshot gives a 404 as far as I can tell

Does this occur in Svelte 5.11.2? Please provide a REPL if so

[akb5566]

Yeah the error page links to a 404 page now. Probably because Svelte team want to ease the confusion caused by this warning/error message. Please have a read at this thread.
sveltejs/svelte#14532

And this PR
sveltejs/svelte#14663

In short: Svelte will fix the overzealous reactive_declaration_non_reactive_property warning in the next release. I'll let you know if this warning persist after next Svelte release. Thanks you.

[akb5566]

Can confirm the warning is gone after updating to svelte@5.11.1. Thanks you.