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

[kgryte]

Resolves a part of #11352.

Description

What is the purpose of this pull request?

This pull request:

• migrates the test assertions in stats/incr/prod 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.

Specifically, this pull request replaces the delta/tol computations in the two t.strictEqual( delta <= tol, ... ) assertions (the "overflow may be transient" and "underflow may be transient" tests) with isAlmostSameValue( actual, expected, 1 ), adds the @stdlib/assert/is-almost-same-value require, and removes the now unused @stdlib/math/base/special/abs and @stdlib/constants/float64/eps requires.

Final ULP constant: 1 for both assertions.

Both assertion sites were tightened to their measured minimum:

Test	Expected	Actual	Minimum ULP
overflow may be transient	1.0715086071862673e+299	1.0715086071862675e+299	1
underflow may be transient	9.332636185032189e-304	9.33263618503219e-304	1

The minimum was measured by evaluating isAlmostSameValue over increasing ULP values and taking the smallest passing integer. Tightness was confirmed by re-running the suite at 0, which fails both assertions (# pass 3425 / # fail 2), while 1 passes all 3427 assertions. The suite was run twice at the final ULP value, with identical results both times, to confirm determinism.

Only test/test.js is modified. The package has no test.native.js.

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

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No.

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
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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 as part of an automated pass over the #11352 migration. The conversion mirrors the idiom established in previously merged stats/incr conversions (e.g. #15257, #15283). The ULP bounds were measured empirically rather than guessed, and verified to be minimal.

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@stdlib-js/reviewers

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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.

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[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
stats/incr/prod	$\\color{green}161/161$ $\\color{green}+100.00\\%$	$\\color{green}11/11$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}161/161$ $\\color{green}+100.00\\%$

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