fix(@stdlib/blas/ext/find-index): supply default fromIndex to gfindIndex

[Planeshifter]

Description

What is the purpose of this pull request?

This pull request:

• fixes a TypeError: Cannot read properties of undefined (reading 'data') in blas/ext/find-index/test/test.assign.js and test.main.js, thrown from ndarraylike2scalar via data-buffer via gfindIndex
• feat!: add fromIndex support to blas/ext/base/ndarray/gfind-index #14478 changed gfindIndex(arrays, clbk, thisArg) to require arrays[1] be a zero-dimensional ndarray specifying a starting search index, calling ndarraylike2scalar(arrays[1]) unconditionally
• blas/ext/find-index registers gfindIndex directly as the default entry in a @stdlib/ndarray/base/unary-reduce-strided1d-dispatch-by-factory table; the shared dispatch machinery (@stdlib/ndarray/base/unary-reduce-strided1d-by) always calls table functions with a single-element arrays array containing only the input view, with no concept of a fromIndex parameter — so arrays[1] was undefined
• in blas/ext/find-index/lib/base.js, wraps gfindIndex in a local indexOf(arrays, clbk) that supplies a constant zero-dimensional fromIndex ndarray (value 0) via scalar2ndarray(0, {dtype: 'generic'}), restoring pre-feat!: add fromIndex support to blas/ext/base/ndarray/gfind-index #14478 default behavior (search the whole array from the start)
• the fix is scoped entirely to the one broken consumer package; the shared dispatch factory and the gfind-index kernel are untouched

Related Issues

Does this pull request have any related issues?

None.

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.

Failing run: https://github.com/stdlib-js/stdlib/actions/runs/32550930877 (run_affected_tests / "Run JavaScript tests"), also reproduced in a macOS Node.js v16 scheduled run (32564148576).

Diff is one file: lib/node_modules/@stdlib/blas/ext/find-index/lib/base.js (+23/-1).

Validation:

• find-index suites pass: test.js (3/3), test.main.js (162/162), test.assign.js (200/200)
• confirmed via git stash that the crash reproduces on pre-fix code and disappears with the fix applied
• make eslint-files on the changed file is clean
• blas/ext/find-last-index checked and unaffected — its kernel gfind-last-index has not yet received the analogous breaking change (pending in unmerged feat: add fromIndex support to blas/ext/base/ndarray/gfind-last-index #14479)
• no other file in the repo reaches into find-index/lib/base.js directly

Reviewed independently by three reviewers (correctness, regression scope, style/conventions); all three approved, no blocking findings.

Non-blocking notes for follow-up:

• unary-reduce-strided1d-by/lib/nd.js calls fcn(v, f, opts), inconsistent with the fcn(v, opts, f) order used by ~40 sibling call sites. Pre-existing, unrelated to this fix, not touched here. Worth a separate issue if a maintainer thinks it's worth fixing.
• once feat: add fromIndex support to blas/ext/base/ndarray/gfind-last-index #14479 merges (fromIndex for gfind-last-index), blas/ext/find-last-index/lib/base.js will hit the identical arrays[1] crash — that PR does not update the consumer. Flagging on feat: add fromIndex support to blas/ext/base/ndarray/gfind-last-index #14479 directly.

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• Read, understood, and followed the contributing guidelines.

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This PR was authored autonomously by an AI agent (a scheduled CI-monitoring routine, using Claude) based on failure analysis of the linked GitHub Actions run. Root-cause analysis, the fix, and validation were performed by the agent; changes were reviewed by three independent review passes before submission.

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Generated by Claude Code

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
blas/ext/find-index	$\\color{green}507/507$ $\\color{green}+100.00\\%$	$\\color{green}55/55$ $\\color{green}+100.00\\%$	$\\color{green}3/3$ $\\color{green}+100.00\\%$	$\\color{green}507/507$ $\\color{green}+100.00\\%$

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

[kgryte]

This is not what is desired.