test: add tests for @stdlib/ndarray/base/descriptor

[Planeshifter]

Resolves https://github.com/stdlib-js/todo/issues/2768.

Description

What is the purpose of this pull request?

This pull request:

• adds tests for @stdlib/ndarray/base/descriptor
• fixes an offset type annotation in docs/repl.txt from integer to NonNegativeInteger (consistent with the JSDoc annotation in lib/main.js)

Specifically, this PR expands the test suite from 2 tests (8 assertions) to 15 tests (81 assertions), adding coverage for:

• column-major array order (generic buffer)
• row-major and column-major with Float64Array typed buffer
• row-major with Float32Array typed buffer
• row-major with Int32Array typed buffer
• row-major with Complex128Array accessor buffer (exercises the accessor buffer path documented in the REPL)
• 1D array (shape [n])
• 0D array (empty shape [], strides [0])
• negative strides with non-zero offset (reversed array)
• 3D array (shape [2,3,4])
• verification that returned value is a plain object (correct prototype chain)
• verification that returned object property insertion order is dtype, data, shape, strides, offset, order — the V8 hidden-class guarantee documented in the package README
• verification that a new object is returned on each invocation while input array references (data, shape, strides) are shared

Additionally, all existing deepEqual assertions for shape and strides were changed to strictEqual to verify that the function stores the original array references rather than copies, which is the intended behavior per the performance motivation documented in the README.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• https://github.com/stdlib-js/todo/issues/2768

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 written primarily by Claude Code.

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@stdlib-js/reviewers

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
ndarray/base/descriptor	$\color{green}102/102$ $\color{green}+100.00%$	$\color{green}3/3$ $\color{green}+100.00%$	$\color{green}1/1$ $\color{green}+100.00%$	$\color{green}102/102$ $\color{green}+100.00%$

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