use es2022 instead of es2020

[Rich-Harris]

closes #8980

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[Conduitry]

We don't need to worry about this being breaking for anyone? All Cloudflare projects are continuously updated to the latest version of their JS engine? There's no setting in their dashboard for this, and projects don't default to staying on the then-latest version when they were originally created?

[Rich-Harris]

Am basing this on cloudflare/workers-sdk#2720. The runtime is kept up to date for all workers. If somehow this did cause a problem for somewhere (and I'm not sure how it could, given what we know) the worker would fail to deploy — it wouldn't cause failures in production

[dummdidumm]

I read that doc as "set a compatibility date in your config and workers will not upgrade beyond that", which means changing the build target likely affects some people.

[Rich-Harris]

Cloudflare regularly updates the Workers runtime. These updates apply to all Workers globally

They update the runtime, but they preserve old bugs

[dummdidumm]

Mhm ok I read it as "runtime is part of the thing you pin", not "code on top of the runtime is what you pin", but maybe that's just me misreading it.

[Rich-Harris]

When it comes to syntax, it's the engine that matters, rather than the runtime, and IIUC workers always run on a recent version of V8 (because of security, and because of the economies of scale from being able to run many workers in a single process regardless of when they were first created). I'm pretty confident this change is safe. If not, we'll find out very soon!