fix: correct typos and errors in blas/ext/base/dediff

[Planeshifter]

Description

Follow-up fixes for commits merged to develop between 2026-05-20 12:04 and 2026-05-20 21:06 (PDT).

This pull request is the output of an automated review of the 18 commits merged to develop in that window (24639c346…e1dd43fdd). Every validated, high-signal issue was grouped by package and committed separately. All findings landed in a single package — blas/ext/base/dediff, added in e46390e26:

blas/ext/base/dediff

• Removed a stray trailing period from the append parameter description in README.md (differences.. → differences.). [e46390e26]
• Corrected the strideA parameter description in README.md: three occurrences read "strides length" (plural) — one in the JS API list and two in the C API lists — inconsistent with the singular "stride length" used by every other stride parameter; changed all three. [e46390e26]
• Fixed the stdlib_strided_dediff_ndarray C usage example in README.md, which passed 16 arguments — a stray 1 immediately after N — for a 15-parameter function; removed the stray argument to match the signature and the sibling sediff example. [e46390e26]
• Corrected the oo parameter in docs/repl.txt, documented as "Stride length for Out" (a copy of the so stride entry); it is the output starting index, so changed it to "Starting index for Out". [e46390e26]
• Removed a stray tab between the ndarray method name and its parameter list in the interface declaration in docs/types/index.d.ts. [e46390e26]
• Corrected the misspelling "eigth" → "eighth" in two test comments in docs/types/test.ts. [e46390e26]
• Corrected the misspelling "twelveth" → "twelfth" in a test comment in docs/types/test.ts. [e46390e26]
• Fixed the positive ($ExpectType) declaration test for dediff.ndarray in docs/types/test.ts, which passed only 14 arguments and omitted the required final offsetOut; added the missing argument to match the 15-parameter signature. [e46390e26]
• Replaced three duplicated stubs in the ndarray "unsupported number of arguments" $ExpectError block in docs/types/test.ts, which left the 4-, 8-, and 12-argument cases untested; the block now steps through every arity, consistent with the sibling sediff and ddiff test files. [e46390e26]
• Fixed subject-verb disagreement in a test description ("the function calculate" → "calculates") across the four dediff test files (test/test.dediff.js, test.ndarray.js, test.dediff.native.js, test.ndarray.native.js). [e46390e26]
• Corrected 16 t.strictEqual assertion messages across the four dediff test files from "return expected value" to "returns expected value", matching the adjacent t.deepEqual messages. [e46390e26]

Related Issues

None.

Questions

No.

Other

Validation

Reviewed: all 18 commits merged to develop in the window (24639c346…e1dd43fdd), via the union diff and per-commit diffs. Four independent review passes were run — two stdlib code-style compliance audits (changed code compared against the established sibling packages ddiff/sdiff/gdiff and the guidelines under docs/style-guides), one diff-only bug scan, and one correctness/security pass over the introduced code (C source, JS lib, declarations, tests).

Checked:

• stdlib code-style compliance for every changed file.
• Objective runtime bugs and copy-paste artifacts across the three new BLAS extension packages (dediff, sediff, zdiff), plus the ndarray/base/order logic fix.
• The mechanical benchmark format(...) refactor (~80 files) for specifier/argument mismatches — none found.

Deliberately excluded:

• Subjective concerns, style preferences not mandated by a style guide, and "might be" issues requiring interpretation.
• One candidate flagged by a single reviewer — an unguarded X[offsetX] read in the new dediff/sediff C *_ndarray routines when N == 0 — was dropped. N == 0 is not a valid input under the package's N + N1 + N2 - 1 output-size contract, the second bug reviewer cleared the same code, and a complete fix would require redesigning the package, outside the scope of this window's diff.

This PR is intentionally left in draft for a maintainer to audit and promote.

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

This pull request was produced end-to-end by an automated Claude Code review routine. Claude enumerated the 24-hour commit window on develop, ran four independent review passes, validated every finding against the affected files and sibling packages, applied the fixes, and drafted this description. All changes are mechanical typo, documentation, and test corrections confined to a single package. A human maintainer should audit before promoting from draft.

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@stdlib-js/reviewers

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Generated by Claude Code

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
blas/ext/base/dediff	$\color{green}446/446$ $\color{green}+100.00%$	$\color{green}17/17$ $\color{green}+100.00%$	$\color{green}4/4$ $\color{green}+100.00%$	$\color{green}446/446$ $\color{green}+100.00%$

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