[Wrangler] Build target ES2022

[JacobMGEvans]

What this PR solves / how to test:
Upgrade the target for JavaScript to ES2022 which is supported in the Worker runtime. You can test that it works by either inspecting your Workers built code or the code being sent over the wire on Publish, if it preserves the ES2022 code then it is working, the only thing we don't support on the Workers runtime (hence 99%) is the ES2022 RegEx feature as seen in the compat table for the latest Chrome version.

Author has included the following, where applicable:

• Tests
• Changeset

Reviewer has performed the following, where applicable:

• Checked for inclusion of relevant tests
• Checked for inclusion of a relevant changeset
• Checked for creation of associated docs updates
• Manually pulled down the changes and spot-tested

Fixes #2716

[changeset-bot]

🦋 Changeset detected

Latest commit: d69b791

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

This PR includes changesets to release 1 package

Name	Type
wrangler	Patch

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Click here if you're a maintainer who wants to add another changeset to this PR

[github-actions]

A wrangler prerelease is available for testing. You can install this latest build in your project with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/runs/4205465154/npm-package-wrangler-2720

You can reference the automatically updated head of this PR with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/prs/2720/npm-package-wrangler-2720

Or you can use npx with this latest build directly:

npx https://prerelease-registry.devprod.cloudflare.dev/runs/4205465154/npm-package-wrangler-2720 dev path/to/script.js

Additional artifacts:

npm install https://prerelease-registry.devprod.cloudflare.dev/runs/4205465154/npm-package-cloudflare-pages-shared-2720

[penalosa]

What about esnext?

[IgorMinar]

What about esnext?

I'd rather not.

esnext is an "unpinned" dependency, and unpinned dependencies of any kind are dangerous as they make it possible for something that used to work well to stop working in the future. This is why npm has a lock file and why semver is a thing.

Sticking to a versioned target requires future bump, but it will be an intentional choice that we control and make rather than a side effect of future esbuild update.

[JacobMGEvans]

What about esnext?

I'd rather not.

esnext is an "unpinned" dependency, and unpinned dependencies of any kind are dangerous as they make it possible for something that used to work well to stop working in the future. This is why npm has a lock file and why semver is a thing.

Sticking to a versioned target requires future bump, but it will be an intentional choice that we control and make rather than a side effect of future esbuild update.

@penalosa Yeah so as much as I would like to, I think this is one of those things we have to manually try to stay on top of as Workerd updates to latest ECMA/V8. If we do something like esnext the compat table looks like this https://kangax.github.io/compat-table/esnext/ which is 5% compat with Chrome 111/112

[codecov]

Codecov Report

Merging #2720 (d69b791) into main (0e10605) will decrease coverage by 5.87%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #2720      +/-   ##
==========================================
- Coverage   74.03%   68.16%   -5.87%     
==========================================
  Files         166      166              
  Lines       10155    10155              
  Branches     2703     2703              
==========================================
- Hits         7518     6922     -596     
- Misses       2637     3233     +596     

Impacted Files	Coverage Δ
packages/wrangler/src/bundle.ts	83.00% <ø> (-10.68%)	⬇️
packages/wrangler/src/entry.ts	68.29% <ø> (-30.09%)	⬇️
packages/wrangler/src/__tests__/helpers/mock-kv.ts	10.00% <0.00%> (-90.00%)	⬇️
...rangler/src/__tests__/helpers/mock-known-routes.ts	28.57% <0.00%> (-71.43%)	⬇️
...r/src/__tests__/helpers/mock-get-zone-from-host.ts	28.57% <0.00%> (-71.43%)	⬇️
packages/wrangler/src/sites.ts	26.81% <0.00%> (-67.40%)	⬇️
packages/wrangler/src/durable.ts	24.32% <0.00%> (-64.87%)	⬇️
packages/wrangler/src/publish/publish.ts	38.10% <0.00%> (-48.60%)	⬇️
packages/wrangler/src/bundle-reporter.ts	51.61% <0.00%> (-48.39%)	⬇️
packages/wrangler/src/create-worker-upload-form.ts	44.23% <0.00%> (-46.16%)	⬇️
... and 15 more

[penalosa]

I didn't release v8 was so far behind esnext! That makes sense to pin to 2022.

[mrbbot]

Nice! Using top-level await to detect es2022 with an error is clever. 🙂