fix: add check for is attribute

[edoardocavazza]

Fixes #15085

Add a check for is attribute in is_custom_element_node function.

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Tests and linting

• Run the tests with pnpm test and lint the project with pnpm lint

[changeset-bot]

🦋 Changeset detected

Latest commit: 57137e6

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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svelte	Patch

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[dummdidumm]

Thank you! Could you add a test to runtime-runes for this? You can look at runtime-runes/custom-element-slot-in-snippet to see how you can model the test

[edoardocavazza]

Hello @dummdidumm, I added the test but I am unable to run pnpm lint 🤷‍♂️ .

[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@15086

[edoardocavazza]

Sure, I'll take a look

[edoardocavazza]

Hi @paoloricciuti, I managed to extend html validation to custom elements with is attribute. I had to refactor some stuff, please let me know if this can work for you.

[paoloricciuti]

Couldn't this also be a custom element?

<svelte:element tag={tag} is="my-element" />

i wonder if we need to add extra checks for the SvelteElement case (before it was using the name so it was probably fine)?

[dummdidumm]

I think we need to revert the changes to validation. When you create a custom element that should be used in place of a regular element, then you do that to mimic the semantics of that element. So <a is="my-a">..</a> is still <a> - and from a quick test the browser seems to see it that way, too, because it still reorders invalid element trees even if they have is=".." on them.

[edoardocavazza]

@dummdidumm You are probably right 🤔 I can easily revert the last commit, let me know how to proceed.

[dummdidumm]

yeah just reverting that last commit sounds good 👍 (sorry for the back and forth)

[paoloricciuti]

And sorry for interjecting and make everybody waste time 😅

[edoardocavazza]

Done!

sorry for the back and forth

And sorry for interjecting and make everybody waste time 😅

No problem at all!

[dummdidumm]

thank you!