🐛 BUG: Compatibility Issue: nodejs_compat_v2 Flag Causes Errors with Vitest Integration @cloudflare/vitest-pool-workers

[ZL-Asica]

Which Cloudflare product(s) does this pertain to?

Wrangler, Workers Vitest Integration

What version(s) of the tool(s) are you using?

3.84.1 [Wrangler], 2.1.4 [Vitest], 0.5.24 [@cloudflare/vitest-pool-workers], 4.5.1 [yarn], 5.6.3 [typescript]

What version of Node are you using?

20.11.1

What operating system and version are you using?

macOS Sequoia 15.1 (24B83)

Describe the Bug

Describe the Bug

According to Cloudflare's documentation on Node.js compatibility (link), setting the compatibility flag to nodejs_compat_v2 should enable compatibility behavior equivalent to nodejs_compat as long as the compatibility date is September 23, 2024, or later. However, using nodejs_compat_v2 results in compatibility issues with Vitest integration in my project, causing the following error during testing:

Error Log

Error: In project vitest.config.mts's configuration file wrangler.toml, `compatibility_flags` must contain "nodejs_compat".
This flag is required to use `@cloudflare/vitest-pool-workers`.
 ❯ assertCompatibilityFlagEnabled ...

Observed Behavior

When using nodejs_compat_v2, Vitest testing fails with a compatibility_flags error indicating that nodejs_compat is required. Switching back to nodejs_compat resolves this error, but it contradicts the expected functionality stated in the documentation.

Expected Behavior

With nodejs_compat_v2 set as the compatibility flag, tests should pass successfully without requiring nodejs_compat.

Steps to Reproduce

1. Set compatibility flag to nodejs_compat_v2 in wrangler.toml with a compatibility date after September 23, 2024.
2. Run tests using @cloudflare/vitest-pool-workers.
3. Observe the compatibility error.

This issue seems to be tied to the interaction between nodejs_compat_v2 and Vitest's Cloudflare integration package.

Please provide a link to a minimal reproduction

https://github.com/ZL-Asica/KumoAuth

Please provide any relevant error logs

Using vars defined in .dev.vars

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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.

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Error: In project vitest.config.mts's configuration file wrangler.toml, `compatibility_flags` must contain "nodejs_compat".
This flag is required to use `@cloudflare/vitest-pool-workers`.
 ❯ assertCompatibilityFlagEnabled node_modules/.store/@cloudflare-vitest-pool-workers-virtual-36b606629f/package/dist/pool/index.mjs:1155:11
 ❯ buildProjectWorkerOptions node_modules/.store/@cloudflare-vitest-pool-workers-virtual-36b606629f/package/dist/pool/index.mjs:1178:3
 ❯ buildProjectMiniflareOptions node_modules/.store/@cloudflare-vitest-pool-workers-virtual-36b606629f/package/dist/pool/index.mjs:1294:47
 ❯ getProjectMiniflare node_modules/.store/@cloudflare-vitest-pool-workers-virtual-36b606629f/package/dist/pool/index.mjs:1321:21
 ❯ Object.runTests node_modules/.store/@cloudflare-vitest-pool-workers-virtual-36b606629f/package/dist/pool/index.mjs:1595:26
 ❯ executeTests node_modules/.store/vitest-virtual-7eb2413551/package/dist/chunks/resolveConfig.DPmbhVlP.js:7678:5
 ❯ node_modules/.store/vitest-virtual-7eb2413551/package/dist/chunks/cli-api.CKrRYkw8.js:10800:9
 ❯ Vitest.runFiles node_modules/.store/vitest-virtual-7eb2413551/package/dist/chunks/cli-api.CKrRYkw8.js:10820:12
 ❯ Vitest.start node_modules/.store/vitest-virtual-7eb2413551/package/dist/chunks/cli-api.CKrRYkw8.js:10663:7

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 Test Files  no tests
      Tests  no tests
     Errors  1 error
   Start at  13:19:48
   Duration  435ms (transform 0ms, setup 0ms, collect 0ms, tests 0ms, environment 0ms, prepare 0ms)


 FAIL  Tests failed. Watching for file changes...
       press h to show help, press q to quit
[vpw:dbg] Shutting down runtimes...