feat: support ES2026 (Explicit Resource Management)

[baseballyama]

I recently added support for using and await using in acorn.
acornjs/acorn@b4ae0d2

However, it seems this is not yet available in the Svelte REPL.
So, I ran the following command to upgrade acorn:

pnpm update acorn
pnpm dedupe acorn

I fixed two failing tests, but I don’t think there’s any issue.

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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: cddfdfb

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

This PR includes changesets to release 1 package

Name	Type
svelte	Minor

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-svelte-16723-svelte.vercel.app/

[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@16723

[baseballyama]

I checked in the Playground, but it still seems to throw an error.
It might need a bit more fixing. I’ll look into it.

[baseballyama]

Please take a look at the following REPL.
When using Explicit Resource Management at the top level, dispose is called at component mount. This feels counterintuitive. Intuitively, it seems more appropriate for it to be called at the onDestroy timing.

Also, if we could make dispose run on onDestroy instead, then from Svelte 6 or 7 onwards we might even be able to deprecate onDestroy. (But before that, it also needs to be implemented in Safari.😅)
I’d love to hear your thoughts on this.

https://svelte.dev/playground/hello-world?version=pr-16723#H4sIAAAAAAAAE5VUwW7bMAz9FUIoUBvznO3qxAGGrsAK9NKlt7pAHJtNhCmUK1FrusD_PiiKE7tNiu1kg-QjH_mevRVUrlFk4gcqpeFFG1VDhLVkrGORiCep0IrsYSv4tfF1PiCSDvWtaVL7GxX72KK0eCpeaWIktiITE1sZ2fC0oILlutGGYQvO4pV2xGighSej13CZjqoQ2XdJ2V6O34OIsGKpaYDrgh2GCq40WQbjaHZ3CzlEMeRT2PpMwaMR3K-khbmzkpbzSwvzWtpGW5x7hIXSAm4arBjrNEB2leAnQT4kEsXjUOKTKW6wcoxRIWbXt9dX9_B1XIjYF7SB10ez7Uo7VXsK8LJCAl4hVHrdaEJikBZqtGz0K9bJvtXCMUiyjGUNkgP501BJkmWp5J_dSgDdQkGEvKfIbqHJ6CgbTRaOWRNoqpSsfuXbTilJlcE1ErfTm-51MgrV04ImzfR-x8MFDgdc5YzxqMmoOT0g6NZOfzqC2d3toadIBOOGRcbGYZucseg7Iw2deirdMyxudn4LBuoZdWAihbzfK4cLyyVj9CXuWU8rTJVeRoW46R9eBLMYZGeos-PS9woXieIueCjaTdlbrE3C83D3bGhsP9tz-pR73w0gD7PX9UKrdG-2x_6kbpHPHejtDt8D6LhA17cdF9SO_1WV3mf6VpFh6kM1Dn-AgSBDwr0qtFwulLSrs_fff7MZRPZZZWDZSFq-Peux-9yb8mJrn1U7j__rymcY1mevW1A7vO1jIriU6kVSLbKnUlls_wIYpjZUzwUAAA

[baseballyama]

We already have PR for this. #16192