fix: prevent ownership warnings if the fallback of a bindable is used

[paoloricciuti]

Closes #15717

I wonder if there's a better way to do this but i couldn't find one. This seems to work however and I'm not to worried about the weirdness because it's in dev only. WDYT?

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Playground

pnpm add https://pkg.pr.new/svelte@15720

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Preview: https://svelte-dev-git-preview-svelte-15720-svelte.vercel.app/

[Ocean-OS]

I think to avoid unexpected behavior like this, we should either use a (weak?)map of bindable fallback proxies instead of adding a property to each one, or omit the symbol from the proxy when using ownKeys.

[paoloricciuti]

I think to avoid unexpected behavior like this, we should either use a (weak?)map of bindable fallback proxies instead of adding a property to each one, or omit the symbol from the proxy when using ownKeys.

Uh weird it should be non enumerable...this definitely needs fixing. Will do tomorrow

[Ocean-OS]

Making a property not enumerable doesn't omit it from Reflect.ownKeys (which retrieves all keys, regardless of enumerability or if they're a symbol), so we'd have to specifically remove it from the ownKeys proxy handler.

[dummdidumm]

What if instead we check if the property is actually in $$props? If not then we can just ignore the warning. No need for any new code in the compiler nor symbols

[paoloricciuti]

What if instead we check if the property is actually in $$props? If not then we can just ignore the warning. No need for any new code in the compiler nor symbols

Dang I knew there was a simpler solution...will fix later!

[paoloricciuti]

@dummdidumm implemented your suggestion 😄

[dummdidumm]

While that's all correct the function name now is confusing because it no longer is what this check is about. is_bound_or_unset maybe?

[paoloricciuti]

Mmm yeah let me change that, even tho I read that as "if it's unset is automatically bound" but maybe it's better to rename it