Use native node:vm module when available

[petebacondarwin]

The native code appears in workerd as of https://github.com/cloudflare/workerd/releases/tag/v1.20250910.0.
It was turned on by default (when nodejs_compat is on) on 2025-10-01.

The remote mode tests would fail if we didn't have a version of workerd in prod that supports this.

Export	workerd	unenv	diff
new Script	throws	fake script object	different
Script.runInContext	throws	throws	same
Script.runInNewContext	throws	throws	same
Script.runInThisContext	throws	throws	same
Script.createCachedData	throws	throws	same
constants	object	object	same
compileFunction	throws	throws	same
createContext	throws	returns fake context object	different
createScript	throws	returns new Script	different
isContext	returns false	returns true if fake context obj	n/a since no way to create in workerd
measureMemory	throws	returns fake promise	different
runInContext	throws	throws	same
runInThisContext	throws	throws	same
runInNewContext	throws	throws	same

• Tests
  • Tests included
  • Tests not necessary because:
• Public documentation
  • Cloudflare docs PR(s):
  • Documentation not necessary because: internal change
• Wrangler V3 Backport
  • Wrangler PR:
  • Not necessary because: unenv is not backported

[changeset-bot]

🦋 Changeset detected

Latest commit: cdd5733

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

Not sure what this means? Click here to learn what changesets are.

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

[pkg-pr-new]

create-cloudflare

npm i https://pkg.pr.new/create-cloudflare@10621

@cloudflare/kv-asset-handler

npm i https://pkg.pr.new/@cloudflare/kv-asset-handler@10621

miniflare

npm i https://pkg.pr.new/miniflare@10621

@cloudflare/pages-shared

npm i https://pkg.pr.new/@cloudflare/pages-shared@10621

@cloudflare/unenv-preset

npm i https://pkg.pr.new/@cloudflare/unenv-preset@10621

@cloudflare/vite-plugin

npm i https://pkg.pr.new/@cloudflare/vite-plugin@10621

@cloudflare/vitest-pool-workers

npm i https://pkg.pr.new/@cloudflare/vitest-pool-workers@10621

@cloudflare/workers-editor-shared

npm i https://pkg.pr.new/@cloudflare/workers-editor-shared@10621

@cloudflare/workers-utils

npm i https://pkg.pr.new/@cloudflare/workers-utils@10621

wrangler

npm i https://pkg.pr.new/wrangler@10621

commit: cdd5733

[vicb]

Thanks.

Changes look good to me.

Could you please add to the PR description what this depends on (the PR in workerd) and in what release is first appears.

Also please update the peer dep on workerd in the unenv-preset to that date

[vicb]

This PR is a breaking change for compat date >= 2025-10-01 as some workerd function throws when unenv polyfill would not.

Could you please details all of those difference in the PR description.

IIRC Next.js uses some of those vm APIs so OpenNext might break after updating wrangler past this PR. We should at least run the Open Next e2e test suite with a compat date after October 1st.

[petebacondarwin]

There are two main differences between the two implementations:

• workerd will throw when you call createContext() whereas unenv returns a fake context object
• workerd will throw if you create a new Script whereas unenv returns a fake script object

If these two are changed then the rest of the differences go away.

[petebacondarwin]

Blocked on cloudflare/workerd#5606

[petebacondarwin]

The upstream PR has now landed, so this will be unblocked when it is released tomorrow.

cloudflare/workerd#5606

[vicb]

rebased + bump workerd to 1202 where the console implementation has been merged