fix: correctly notify page store subscribers

[eltigerchino]

fixes #13200

This PR ensures page store subscribers are correctly notified by creating a new object whenever we update the page store. I'm not sure why but when the same page object is used, it doesn't notify subscribers.

There was also another bug where a popstate event would cause subscribers to get notified twice because we were calling root.$set({ page }) in addition to stores.page.notify() when updating the URL.

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[ranjan-purbey]

Thanks for the fix @eltigerchino! Do you think it'd make sense to extract page state to props.page conversion into a utility function to avoid repetitiveness?

[ranjan-purbey]

Probably this line also needs to be updated. @eltigerchino

[eltigerchino]

update_url already notifies the store so we don't need root.$set({ page }); or it will be notified twice

[ciscoheat]

Hello, any progress on this one? It's unfortunately causing a bit of problem with Superforms, I've been getting many issues lately about it. It would be great if it can be patched soon. :)

[dummdidumm]

• is there a reason why we can't just do page: { ...page }?
• if we can't do that, then this should be moved into a helper function and reused across the change sites to reduce a bit of code size

[eltigerchino]

Yeah, no clue why but spreading with { ...page } just returns an empty object. Maybe @Rich-Harris knows

Added a helper in 51a5ea7 (#13205)

[dummdidumm]

ah, it's because of the class with $state.raw on it, producing getters which are not spreadable

[Rich-Harris]

preview: https://svelte-dev-git-preview-kit-13205-svelte.vercel.app/

this is an automated message

[gyzerok]

@eltigerchino is it possible to have a release with this merged?

[eltigerchino]

It's in the next release #13277

[gyzerok]

@eltigerchino yeah noticed that. Is it possible to cut it off already or does it wait for something?