[test optimization] Support new pools in vitest

[juan-fernandez]

What does this PR do?

Add instrumentation for ForksPoolWorker and ThreadsPoolWorker, which substitute tinypool.

Motivation

vitest@4 got rid of tinypool altogether: vitest-dev/vitest#8705 (https://github.com/vitest-dev/vitest/releases/tag/v4.0.0), so we need to re-support IPC for the new pools.

This change hasn't broken our tests because our instrumentation has graceful degradation: if the worker can't find TINYPOOL_WORKER_ID, it will report just like the main process, directly to the intake or agent. The instrumentation is more fragible (workers can be shut down with a request in flight) but it still reports data if it can.

Plugin Checklist

The already present integration tests should be enough, as they check test.vitest.pool. This checks that the new instrumentation is kicking in.

• Integration tests.

[github-actions]

Overall package size

Self size: 13.15 MB
Deduped: 117.18 MB
No deduping: 119.39 MB

Dependency sizes

| name | version | self size | total size | |------|---------|-----------|------------| | @datadog/libdatadog | 0.7.0 | 35.02 MB | 35.02 MB | | @datadog/native-appsec | 10.3.0 | 20.73 MB | 20.74 MB | | @datadog/native-iast-taint-tracking | 4.0.0 | 11.72 MB | 11.73 MB | | @datadog/pprof | 5.12.0 | 11.19 MB | 11.57 MB | | @opentelemetry/core | 1.30.1 | 908.66 kB | 7.16 MB | | protobufjs | 7.5.4 | 2.95 MB | 5.82 MB | | @datadog/wasm-js-rewriter | 4.0.1 | 2.85 MB | 3.58 MB | | @opentelemetry/resources | 1.9.1 | 306.54 kB | 1.74 MB | | @datadog/native-metrics | 3.1.1 | 1.02 MB | 1.43 MB | | @opentelemetry/api-logs | 0.207.0 | 201.39 kB | 1.42 MB | | @opentelemetry/api | 1.9.0 | 1.22 MB | 1.22 MB | | jsonpath-plus | 10.3.0 | 617.18 kB | 1.08 MB | | import-in-the-middle | 1.15.0 | 127.66 kB | 856.24 kB | | lru-cache | 10.4.3 | 804.3 kB | 804.3 kB | | @datadog/openfeature-node-server | 0.1.0-preview.12 | 95.11 kB | 401.68 kB | | opentracing | 0.14.7 | 194.81 kB | 194.81 kB | | source-map | 0.7.6 | 185.63 kB | 185.63 kB | | pprof-format | 2.2.1 | 163.06 kB | 163.06 kB | | @datadog/sketches-js | 2.1.1 | 109.9 kB | 109.9 kB | | lodash.sortby | 4.7.0 | 75.76 kB | 75.76 kB | | ignore | 7.0.5 | 63.38 kB | 63.38 kB | | istanbul-lib-coverage | 3.2.2 | 34.37 kB | 34.37 kB | | rfdc | 1.4.1 | 27.15 kB | 27.15 kB | | dc-polyfill | 0.1.10 | 26.73 kB | 26.73 kB | | @isaacs/ttlcache | 1.4.1 | 25.2 kB | 25.2 kB | | tlhunter-sorted-set | 0.1.0 | 24.94 kB | 24.94 kB | | shell-quote | 1.8.3 | 23.74 kB | 23.74 kB | | limiter | 1.1.5 | 23.17 kB | 23.17 kB | | retry | 0.13.1 | 18.85 kB | 18.85 kB | | semifies | 1.0.0 | 15.84 kB | 15.84 kB | | jest-docblock | 29.7.0 | 8.99 kB | 12.76 kB | | crypto-randomuuid | 1.0.0 | 11.18 kB | 11.18 kB | | ttl-set | 1.0.0 | 4.61 kB | 9.69 kB | | mutexify | 1.4.0 | 5.71 kB | 8.74 kB | | path-to-regexp | 0.1.12 | 6.6 kB | 6.6 kB | | module-details-from-path | 1.0.4 | 3.96 kB | 3.96 kB | | escape-string-regexp | 5.0.0 | 3.66 kB | 3.66 kB |

_{🤖 This report was automatically generated by heaviest-objects-in-the-universe}

[codecov]

Codecov Report

❌ Patch coverage is 50.00000% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 83.78%. Comparing base (870560e) to head (b4df8f5).

Files with missing lines	Patch %	Lines
...e/src/ci-visibility/exporters/test-worker/index.js	25.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6812      +/-   ##
==========================================
- Coverage   83.79%   83.78%   -0.02%     
==========================================
  Files         506      506              
  Lines       21271    21275       +4     
==========================================
+ Hits        17825    17826       +1     
- Misses       3446     3449       +3     

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[juan-fernandez]

no changes, just made it async

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-11-03 11:19:39

Comparing candidate commit b4df8f5 in PR branch juan-fernandez/support-v4-new-pools with baseline commit 870560e in branch master.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 1606 metrics, 64 unstable metrics.