test: migrate stats/incr/nanmmeanvar to ULP-based assertions

[kgryte]

Resolves a part of #11352.

Description

What is the purpose of this pull request?

This pull request:

• migrates the tests for stats/incr/nanmmeanvar from relative tolerance testing to ULP difference testing, per [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352.

Implementation notes:

• The package contained a single relative-tolerance assertion (in test/test.js, within the "if not provided an input value, the accumulator function returns the current accumulated values" test). The delta/tol computation was removed and replaced with t.strictEqual( isAlmostSameValue( actual[ 1 ], expected[ 1 ], 0 ), true, 'returns expected value' );.
• Added the @stdlib/assert/is-almost-same-value require and removed the now unused @stdlib/math/base/special/abs and @stdlib/constants/float64/eps requires.
• Final ULP constant: 0. Starting from an ULP bound of 64, the bound was tightened downward to the minimum passing integer. The accumulated unbiased sample variance for the test input ([ 2.0, NaN, 3.0, 10.0 ], window size 3) is bit-identical to the expected value 19.0, so no ULP slack is required. 0 is therefore both the measured minimum and the floor.
• The test suite was run twice at the final bound (make test TESTS_FILTER=".*/stats/incr/nanmmeanvar/.*"), passing 282/282 assertions both times, confirming determinism.
• This package has no test/test.native.js, so test/test.js is the only changed file.
• This mirrors the idiom established for the sibling package in d9ecdf5 (test: migrate stats/incr/nanmmeanstdev to ULP-based assertions), which also settled on an ULP bound of 0.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352

Questions

Any questions for reviewers of this pull request?

No.

Other

Any other information relevant to this pull request? This may include screenshots, references, and/or implementation notes.

make eslint-tests TESTS_FILTER=".*/stats/incr/nanmmeanvar/.*" is clean. The project pre-commit and commit-msg hooks ran and passed; only the EditorConfig lint step was skipped, as this environment cannot download the editorconfig-checker binary. EditorConfig conformance (LF endings, tab indentation, final newline, no new trailing whitespace) was verified manually instead.

Checklist

Please ensure the following tasks are completed before submitting this pull request.

• Read, understood, and followed the contributing guidelines.

AI Assistance

When authoring the changes proposed in this PR, did you use any kind of AI assistance?

• Yes
• No

If you answered "yes" above, how did you use AI assistance?

• Code generation (e.g., when writing an implementation or fixing a bug)
• Test/benchmark generation
• Documentation (including examples)
• Research and understanding

Disclosure

If you answered "yes" to using AI assistance, please provide a short disclosure indicating how you used AI assistance. This helps reviewers determine how much scrutiny to apply when reviewing your contribution. Example disclosures: "This PR was written primarily by Claude Code." or "I consulted ChatGPT to understand the codebase, but the proposed changes were fully authored manually by myself.".

This PR was authored by Claude Code, running as an unattended scheduled task. It studied #11352 and the diffs of previously converted packages to mirror the established idiom, applied the mechanical conversion, and then searched downward from an ULP bound of 64 to determine the minimum passing bound empirically.

---

🤖 Generated with Claude Code

https://claude.ai/code/session_014rFkWW1YS1fbtCqw2qnykJ

---

Generated by Claude Code

[stdlib-bot]

Hello! 👋

We've noticed that you've been opening a number of PRs addressing good first issues. Thank you for your interest and enthusiasm!

Now that you've made a few contributions, we suggest no longer working on good first issues. Instead, we encourage you to prioritize cleaning up any PRs which have yet to be merged and then proceed to work on more involved tasks.

Not only does this ensure that other new contributors can work on things and get ramped up on all things stdlib, it also ensures that you can spend your time on more challenging problems. 🚀

For ideas for future PRs, feel free to search the codebase for TODOs and FIXMEs and be sure to check out other open issues on the issue tracker. Cheers!

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
stats/incr/nanmmeanvar	$\\color{green}143/143$ $\\color{green}+100.00\\%$	$\\color{green}10/10$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}143/143$ $\\color{green}+100.00\\%$

The above coverage report was generated for the changes in this PR.