[kgryte]

Resolves a part of #11352.

Description

What is the purpose of this pull request?

This pull request:

• migrates the tests for math/base/special/boxcox1p from relative tolerance testing (delta <= tol, where tol = N * EPS * abs( expected )) to ULP difference testing using @stdlib/assert/is-almost-same-value, as proposed in [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352.

Changes are limited to test/test.js and test/test.native.js. In each fixture loop, the if ( b === expected[ i ] ) { ... } else { ... } tolerance branch is replaced by a single assertion of the form

t.strictEqual( isAlmostSameValue( b, expected[ i ], N ), true, 'returns expected value' );

the now-unused delta/tol locals and the @stdlib/math/base/special/abs import are removed, and the @stdlib/assert/is-almost-same-value import is added. The @stdlib/constants/float64/eps import is retained, as EPS is still used when generating random inputs less than negative one. No test cases, fixtures, or assertion counts were added or removed.

ULP bounds

Each bound is the measured minimum for its fixture, determined by computing the ULP difference for every fixture value and taking the maximum. Both test files use the same bounds, mirroring the existing convention for JavaScript/C test pairs.

Fixture	Previous tolerance	ULP bound
medium_positive	17.0 * EPS	27
small_positive	4.0 * EPS	4
very_small	1.0 * EPS	0
tiny	1.0 * EPS	0
tiny_and_large_lambda	3.0 * EPS	2
tiny_lambda	1.0 * EPS	1

Each bound was confirmed tight by lowering it by one and re-running the suite; every reduction produces failures (27→26: 1 failure, 4→3: 7, 2→1: 24, 1→0: 187). The very_small and tiny fixtures match exactly, so 0 is the minimum by construction. The full suite (11089 assertions) passes, and was run twice at the final bounds to confirm the results are deterministic.

Note: the native add-on could not be compiled in the environment used to author this change, so test/test.native.js was verified to load and skip cleanly, but its bounds were not exercised locally and rely on CI. The C implementation is a direct port of the JavaScript implementation and calls stdlib's own log1p/expm1, so the same bounds are expected to hold.

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.

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
• 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, which performed the mechanical test migration and empirically measured the minimum ULP bounds.

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@stdlib-js/reviewers

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Generated by Claude Code

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
math/base/special/boxcox1p	$\\color{green}232/232$ $\\color{green}+100.00\\%$	$\\color{green}16/16$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}232/232$ $\\color{green}+100.00\\%$

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