🐛 BUG: npm test fails on fresh hello world create cloudflare project

[irvinebroque]

Which Cloudflare product(s) does this pertain to?

C3 (npm create cloudflare), Wrangler, Workers Vitest Integration

What versions are you using?

Wrangler 3.103.2
C3 10.9.2
"@cloudflare/vitest-pool-workers": "^0.5.2",

What operating system and version are you using?

Mac latest

Please provide a link to a minimal reproduction

https://github.com/irvinebroque/vitest-breakpoint

Describe the Bug

1. npm create cloudflare@latest
2. Hello World + TypeScript
3. cd project directory
4. npm test
5. Observe error

➜  vitest-breakpoint git:(main) npm run test

> vitest-breakpoint@0.0.0 test
> vitest


 DEV  v2.1.8 /Users/brendan/src/proj/vitest-breakpoint


⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ Unhandled Errors ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯

Vitest caught 1 unhandled error during the test run.
This might cause false positive tests. Resolve unhandled errors to make sure your tests are not affected.

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ Unhandled Error ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
Error: In project vitest.config.mts's configuration file wrangler.json, `compatibility_flags` must contain one of "nodejs_compat"/"nodejs_compat_v2".
Either one of these flags is required to use `@cloudflare/vitest-pool-workers`.
 ❯ buildProjectWorkerOptions node_modules/@cloudflare/vitest-pool-workers/dist/pool/index.mjs:1270:13
 ❯ buildProjectMiniflareOptions node_modules/@cloudflare/vitest-pool-workers/dist/pool/index.mjs:1382:47
 ❯ getProjectMiniflare node_modules/@cloudflare/vitest-pool-workers/dist/pool/index.mjs:1409:21
 ❯ Object.runTests node_modules/@cloudflare/vitest-pool-workers/dist/pool/index.mjs:1683:26
 ❯ executeTests node_modules/vitest/dist/chunks/resolveConfig.RxKrDli4.js:7680:5
 ❯ node_modules/vitest/dist/chunks/cli-api.C2yC_ESk.js:10798:9
 ❯ Vitest.runFiles node_modules/vitest/dist/chunks/cli-api.C2yC_ESk.js:10820:12
 ❯ Vitest.start node_modules/vitest/dist/chunks/cli-api.C2yC_ESk.js:10662:7
 ❯ startVitest node_modules/vitest/dist/chunks/cli-api.C2yC_ESk.js:11828:7

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯

 Test Files  no tests
      Tests  no tests
     Errors  1 error
   Start at  09:33:12
   Duration  407ms (transform 0ms, setup 0ms, collect 0ms, tests 0ms, environment 0ms, prepare 0ms)

refs #7388 ?

Pretty sure this is happening because npm create cloudflare@latest is not installing latest version of the vitest-pool-workers package

[irvinebroque]

The actual version of vitest-pool-workers that is getting installed on fresh npm create cloudflare@latest is 0.5.41 rather than latest version we have published? 0.64 (link)

    "node_modules/@cloudflare/vitest-pool-workers": {
      "version": "0.5.41",

[irvinebroque]

Yep everything passes soon as I pin.

[irvinebroque]

I gather from #7742 that we don't automate updating dependency versions for C3 templates and can get behind.

I think if we did — then this issue possibly wouldn't have happened, since templates would already automatically start using latest published version? A good prevents?

[edmundhung]

The actual version of vitest-pool-workers that is getting installed on fresh npm create cloudflare@latest is 0.5.41 rather than latest version we have published? 0.64 (link)

"node_modules/@cloudflare/vitest-pool-workers": {
  "version": "0.5.41",

This is likely because vitest-pool-workers is still on major version 0. In this case, a minor version bump is treated as a breaking change, so a version range like ^0.5.2 will only upgrade to 0.5.41 and not to 0.6 or above.

I have addressed this by bumping the version in #7827. We will need to be mindful when updating vitest-pool-workers versions until it reaches v1.

[edmundhung]

Just discussed this with the team. Since vitest-pool-workers is still on a 0 major version, minor version bumps can include breaking changes. This explains why the templates weren't updated to the next minor version for you.

In this case, we should have updated both the compatibility_flags and the vitest-pool-workers version together. I will add some tests in #7827 to catch this in the future. 👍🏼

[vhscom]

Can confirm updating @cloudflare/vitest-pool-workers from installed version fixes the test failure.

npm ls
c3-minimal-workerd-ci-error@0.0.0 /Users/vhs/Developer/c3-minimal-workerd-ci-error
├── @cloudflare/vitest-pool-workers@0.5.41 # this version requires adding nodejs_compat flag to config
├── @cloudflare/workers-types@4.20250121.0
├── typescript@5.7.3
├── vitest@2.1.8
└── wrangler@3.103.2

Affected version of c3: create-cloudflare v2.37.1

[irvinebroque]

Awesome. Thanks all!