[ShakilUrRehman21]

Description

ECMAScript defines both TypedArray and DataView as subclasses of ArrayBufferView (ArrayBuffer.isView(x) returns true for both).

While other buffer methods like Buffer.byteLength() accept any ArrayBufferView (including DataView), buffer.isUtf8(), buffer.isAscii(), and Buffer.stringLength() restricted their argument validation to isTypedArray() and IsTypedArray(). Passing a DataView threw TypeError [ERR_INVALID_ARG_TYPE].

The underlying C++ helper ArrayBufferViewContents<T> in src/util-inl.h already natively supports v8::ArrayBufferView (including DataView).

This PR:

1. Updates lib/buffer.js to validate with isArrayBufferView() instead of isTypedArray(), and includes 'DataView' in the ERR_INVALID_ARG_TYPE expected types.
2. Updates src/node_buffer.cc to check IsArrayBufferView() instead of IsTypedArray().
3. Updates doc/api/buffer.md to document DataView support.
4. Adds test cases covering DataView in test-buffer-isutf8.js, test-buffer-isascii.js, and test-buffer-stringlength.js.

Refs: #64503
Refs: #64504
Refs: #66064

Checklist

• test passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

[github-actions]

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[MikeMcC399]

The recommendations in:

• Guides and FAQs for first-time contributors

advise you should tackle only one issue at a time and that you should not open any new PRs until your first PR has been approved.

You already have unapproved PR #67178 open at this time which you opened just before this PR.

Until the first PR has been approved and has landed in the main branch, GitHub classifies you as "first-time contributor". Each PR commit you push needs to be individually approved by team members to run in GitHub Actions CI. This causes delays for you as a contributor, and it adds to the work load for the team.

Waiting until the first PR has landed ensures that you as a contributor have experienced the complete process from PR submission to successful landing. After this has been completed, any new PRs or new commits to an existing PR are treated to rules for regular Contributors. GitHub Actions CI workflows are then run automatically without intervention by a team member.

[ShakilUrRehman21]

The recommendations in:

• Guides and FAQs for first-time contributors

advise you should tackle only one issue at a time and that you should not open any new PRs until your first PR has been approved.

You already have unapproved PR #67178 open at this time which you opened just before this PR.

Until the first PR has been approved and has landed in the main branch, GitHub classifies you as "first-time contributor". Each PR commit you push needs to be individually approved by team members to run in GitHub Actions CI. This causes delays for you as a contributor, and it adds to the work load for the team.

Waiting until the first PR has landed ensures that you as a contributor have experienced the complete process from PR submission to successful landing. After this has been completed, any new PRs or new commits to an existing PR are treated to rules for regular Contributors. GitHub Actions CI workflows are then run automatically without intervention by a team member.

Thank you for pointing that out and for the guidance! That makes complete sense.

I've converted this PR to draft for now so the team can focus on first PR.

[anonrig]

these changes require updates to typings folder as well...