stream: use validateObject for zlib/iter params

[greenheadHQ]

Replace the open-coded object check in validateParams() with validateObject using the kValidateObjectAllowArray flag. The flag matches the previous typeof params !== 'object' || params === null semantics case by case: arrays keep passing, null and other primitives keep rejecting. Both paths construct ERR_INVALID_ARG_TYPE with identical arguments, so the error type, code, and message are unchanged.

The added test locks the array-accepting boundary, which was not covered by the existing validation tests, and passes with and without the lib change.

[nodejs-github-bot]

Review requested:

• @nodejs/streams

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.28%. Comparing base (31cde9f) to head (163140a).
⚠️ Report is 205 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #65015      +/-   ##
==========================================
- Coverage   90.30%   90.28%   -0.02%     
==========================================
  Files         759      759              
  Lines      247621   247633      +12     
  Branches    46672    46688      +16     
==========================================
- Hits       223603   223585      -18     
- Misses      15473    15515      +42     
+ Partials     8545     8533      -12     

Files with missing lines	Coverage Δ
lib/internal/streams/iter/transform.js	95.72% <100.00%> (-0.01%)	⬇️

... and 38 files with indirect coverage changes

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[greenheadHQ]

@nodejs/streams Could someone take a look at this? It swaps an open-coded object check in validateParams() for the existing validateObject helper, keeping the same error via kValidateObjectAllowArray. CI is green.

[greenheadHQ]

@jasnell You wrote stream/iter, so you may be the right person to look at this one. It's a small refactor of the options.params check, with the array-accepting behaviour preserved.

[greenheadHQ]

@jasnell Thanks for reviewing and approving this!

The failures in CI #75831 appear unrelated to this change. The Node.js reliability report records the same failures across multiple unrelated PRs:

• ffi/test-ffi-fast-integer-validation
• parallel/test-stream-pipeline-http2
• test-runner/test-run-watch-cwd-isolation-none-argv

https://github.com/nodejs/reliability/blob/main/reports/2026-08-15.md

Would you mind resuming the top-level CI job when you have a chance?

https://ci.nodejs.org/job/node-test-pull-request/75831/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/75899/

[nodejs-github-bot]

Landed in 1dacb39