test: migrate math/base/special/fast/pow-int to ULP-based assertions

[ujjwalv01]

Resolves part of #11352

Description

What is the purpose of this pull request?

This pull request:

• Migrates tests in @stdlib/math/base/special/fast/pow-int to use ULP-based testing assertions. Specifically, both test.js and test.native.js were updated to replace absolute tolerance checks with exact ULP assertions using @stdlib/assert/is-almost-same-value.

ULP Tolerance Explanation

The ULP tolerance values used (126, 113, and 6) represent the exact, tightest minimums required to pass the test fixtures:

• decimalInteger: 126 ULP
• integerInteger: 113 ULP
• multiplesOfTen: 6 ULP

Previously, the tests used relative absolute tolerances of 70.0 * EPS * abs(expected), 61.0 * EPS * abs(expected), and 3.75 * EPS * abs(expected). Because the absolute value can scale up to almost 2 within a floating-point exponent bin, those older tolerances effectively allowed for up to ~140 ULP, ~122 ULP, and ~7.5 ULP differences in the worst-case scenarios.

By programmatically computing the exact maximum ULP differences against the expected Julia outputs, we were able to successfully tighten these thresholds to the absolute minimum bounds required to pass all edge cases.

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

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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

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Coverage Report

Package	Statements	Branches	Functions	Lines
math/base/special/fast/pow-int	$\\color{green}323/323$ $\\color{green}+100.00\\%$	$\\color{green}18/18$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}323/323$ $\\color{green}+100.00\\%$

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