Expose a couple string utils

[Craig Macomber (Microsoft) (CraigMacomber)]

Description

These are somewhat questionable helper methods that we have some interest in using experimentally in some applications for now until we can think of a better approach (or decide they make sense and stabilize them more).

They are being exposed as alpha instead of internal to help with this.

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[github-actions]

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[Copilot]

Pull request overview

Exposes existing Unicode string helper utilities from @fluidframework/tree by changing their TSDoc visibility to Alpha (@Alpha), and refactors validation/error behavior to use the shared validateIndex helper while expanding tests and adding benchmark coverage.

Changes:

• Promote codePointCount and utf16LengthForCodePoints from @internal to @alpha, adding stability caveats in @privateRemarks.
• Refactor utf16LengthForCodePoints argument validation to use validateIndex, aligning error messages and updating tests accordingly.
• Add micro-benchmarks comparing the codePointAt approach with a reference implementation.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
packages/dds/tree/src/text/codePointUtils.ts	Promote APIs to @alpha, add caveats, and refactor validation to validateIndex.
packages/dds/tree/src/test/text/codePointUtils.spec.ts	Expand correctness tests to cover multiple implementations and add benchmark cases.
.vscode/settings.json	Minor formatting cleanup and add misalign to cSpell dictionary.

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[Joshua Smithrud (Josmithr)]

Left a few suggestions. Overall looks good.

[github-actions]

Bundle size comparison

Base commit: 4ef2d87f605f6d8947b691da4fbce3af6338f9b1
Head commit: 1ed310b117bb4b189d9fe2608c5313f4853e2a7f

Notable changes

No bundles changed by ≥ 500 bytes parsed.

Per-bundle deltas

@fluid-example/bundle-size-tests

• fluidFrameworkAllAlpha.js: parsed 784481 → 784959 (+478), gzip 215047 → 215279 (+232)
• azureClient.js: parsed 625038 → 625094 (+56), gzip 166669 → 166712 (+43)
• odspClient.js: parsed 597494 → 597550 (+56), gzip 159859 → 159901 (+42)
• aqueduct.js: parsed 531249 → 531284 (+35), gzip 142123 → 142151 (+28)
• fluidFramework.js: parsed 403781 → 403802 (+21), gzip 114492 → 114508 (+16)
• sharedTree.js: parsed 393185 → 393199 (+14), gzip 111934 → 111941 (+7)
• containerRuntime.js: parsed 309170 → 309184 (+14), gzip 84577 → 84584 (+7)
• sharedString.js: parsed 176536 → 176543 (+7), gzip 49804 → 49812 (+8)
• experimentalSharedTree.js: parsed 160691 → 160691 (0), gzip 46272 → 46272 (0)
• matrix.js: parsed 160367 → 160374 (+7), gzip 45805 → 45812 (+7)
• loader.js: parsed 145725 → 145739 (+14), gzip 39292 → 39307 (+15)
• odspDriver.js: parsed 104263 → 104284 (+21), gzip 32489 → 32496 (+7)
• directory.js: parsed 67136 → 67143 (+7), gzip 18867 → 18874 (+7)
• 578.js: parsed 58686 → 58686 (0), gzip 17657 → 17657 (0)
• map.js: parsed 47231 → 47238 (+7), gzip 14462 → 14469 (+7)
• odspPrefetchSnapshot.js: parsed 45751 → 45765 (+14), gzip 15260 → 15269 (+9)
• 252.js: parsed 44362 → 44362 (0), gzip 13735 → 13735 (0)
• summarizerDelayLoadedModule.js: parsed 30717 → 30717 (0), gzip 7716 → 7716 (0)
• socketModule.js: parsed 26469 → 26476 (+7), gzip 7896 → 7903 (+7)
• createNewModule.js: parsed 12474 → 12474 (0), gzip 4810 → 4810 (0)
• summaryModule.js: parsed 3789 → 3789 (0), gzip 1857 → 1857 (0)
• connectionState.js: parsed 909 → 909 (0), gzip 500 → 500 (0)
• sharedTreeAttributes.js: parsed 847 → 854 (+7), gzip 499 → 508 (+9)
• debugAssert.js: parsed 429 → 429 (0), gzip 299 → 299 (0)
• FluidFramework-HashFallback.js: parsed 419 → 419 (0), gzip 313 → 313 (0)

[github-actions]

🔗 Found some broken links! 💔

Run a link check locally to find them. See Checking for Broken Links for more information.

linkcheck output

1: starting server using command "npm run serve -- --no-open"
and when url "[ 'http://127.0.0.1:3000' ]" is responding with HTTP status code 200
running tests using command "npm run check-links"


> fluid-framework-website@0.0.0 serve
> docusaurus serve --no-open

[SUCCESS] Serving "build" directory at: http://localhost:3000/
[ELIFECYCLE] Command failed with exit code 1.