test: migrate math/base/special/ccis to ULP-based assertions

[Planeshifter]

Resolves a part of #11352.

Description

What is the purpose of this pull request?

This pull request:

• Migrates math/base/special/ccis test cases from relative-tolerance (EPS-scaled delta/tol) comparisons to ULP-based assertions using @stdlib/assert/is-almost-same-value, per the RFC in [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352.
• Updates both test/test.js and test/test.native.js.
• Measured the minimum ULP threshold that still passes over the full fixture set (pure_real.json, general_complex.json), confirmed deterministic across three consecutive local runs (including a build of the native addon via node-gyp):
  • test.js (pure JS implementation): 0 ULP for both the real and imaginary components, across both fixture sets (exact bit-for-bit match against the reference fixtures).
  • test.native.js (native addon): 0 ULP for both the real and imaginary components, across both fixture sets (also an exact match).

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.

• Only the two test files for math/base/special/ccis were changed; no other packages were touched.
• Verified: make test TESTS_FILTER=".*/math/base/special/ccis/.*" passes (2018/2018 for both test.js and the native addon build of test.native.js), run three times to confirm determinism, and make eslint-tests TESTS_FILTER=".*/math/base/special/ccis/.*" (the repo's test-specific ESLint config) is clean on both files.
• Studied prior-art conversions of similar complex-valued packages (e.g. math/base/special/cexp, and the reference commit 121f2c0 linked from the RFC) to mirror the exact idiom, including using literal per-assertion ULP values (rather than a single named constant) since that matches the convention used across all merged conversions in this codebase to date.

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 written entirely by Claude Code (an automated, unattended session), including discovering the candidate package, checking for collisions with existing/prior ULP-migration PRs, studying prior-art conversions (e.g. math/base/special/cexp), rewriting the test assertions, building the native addon locally to measure the native-implementation ULP threshold empirically, and verifying determinism across repeated runs. It is left as a draft specifically so a human can review it before it is considered for merge, given issue #11352 encourages contributors to author these migrations manually.

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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/ccis	$\\color{green}198/198$ $\\color{green}+100.00\\%$	$\\color{green}6/6$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}198/198$ $\\color{green}+100.00\\%$

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