[daesunp]

Description

Updates collab text plain text selection tracking to use the array node anchor tracking feature.

[github-actions]

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[Copilot]

Pull request overview

Updates the React plain-text collaboration utilities to track textarea selections via PlainText.Tree insertion anchors, so selections follow remote edits without manual per-delta cursor math.

Changes:

• Add PlainText.Tree.createInsertionAnchor() (tree) and switch selection tracking to use anchor indices (React hook + editor view).
• Extend useTreeSynchronizedString to expose setSelection() and compute selections from anchors.
• Simplify applyTextOps to only return the updated string; expand tests to cover anchor-based selection behaviors (including hydration and surrogate pairs).

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
packages/framework/react/src/text/plain/useTreeSynchronizedString.ts	Reworks selection tracking to use insertion anchors and exposes setSelection() to update tracked selection.
packages/framework/react/src/text/plain/plainUtils.ts	Simplifies applyTextOps to return just the updated string; keeps reread-based selection remapping helper.
packages/framework/react/src/text/plain/plainTextView.tsx	Wires textarea onSelect/onChange to setSelection() so the editor can preserve selection across remote edits.
packages/framework/react/src/test/text/useTreeSynchronizedString.spec.ts	Adds/updates tests for anchor-based selection behavior, bounds clamping, surrogate pairs, and hydration.
packages/framework/react/src/test/text/plainUtils.test.ts	Updates tests to match the simplified applyTextOps return type and scope.
packages/framework/react/api-report/react.alpha.api.md	API report update for SynchronizedString.setSelection.
packages/framework/fluid-framework/api-report/fluid-framework.alpha.api.md	API report update for PlainText.Tree.createInsertionAnchor.
packages/dds/tree/src/text/textDomainFormatted.ts	Adds createInsertionAnchor implementation for formatted text’s underlying content array.
packages/dds/tree/src/text/textDomain.ts	Adds createInsertionAnchor to PlainText members and implements it via array insertion anchors.
packages/dds/tree/src/test/text/textDomain.spec.ts	Adds hydration test verifying insertion anchors track across edits.
packages/dds/tree/api-report/tree.alpha.api.md	API report update for PlainText.Tree.createInsertionAnchor.
.changeset/small-suns-tickle.md	Declares minor bumps and documents the new anchor-based selection tracking behavior.

Suppressed comments (2)

packages/framework/react/src/text/plain/plainTextView.tsx:108

• HTMLTextAreaElement.selectionStart/selectionEnd are typed as number | null. Normalize them (e.g. ?? 0) before calling setSelection to avoid null propagation / TS errors.

		(event: SyntheticEvent<HTMLTextAreaElement>) => {
			setSelection({
				start: event.currentTarget.selectionStart,
				end: event.currentTarget.selectionEnd,
			});

packages/framework/react/src/text/plain/useTreeSynchronizedString.ts:78

• The example uses selectionStart/selectionEnd directly, but in TS DOM typings these are number | null. Adding a fallback avoids TS errors when consumers copy/paste this snippet.

 *     onChange={(e) => {
 *       TreeAlpha.context(tree).runTransaction(() => syncTextToTree(tree, e.target.value));
 *       setSelection({ start: e.target.selectionStart, end: e.target.selectionEnd });
 *     }}

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[Joshua Smithrud (Josmithr)]

Added a couple more comments, but otherwise this is looking good to me.

[Joshua Smithrud (Josmithr)]

daesunp Craig is merging a PR that makes the tree API changes here. #28045

[github-actions]

🔗 No broken links found! ✅

Your attention to detail is admirable.

linkcheck output

$ start-server-and-test "npm run serve -- --host 127.0.0.1 --no-open" http://127.0.0.1:3000 check-links
1: starting server using command "npm run serve -- --host 127.0.0.1 --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 --host 127.0.0.1 --no-open

[SUCCESS] Serving "build" directory at: http://127.0.0.1:3000/

> fluid-framework-website@0.0.0 check-links
> linkcheck http://127.0.0.1:3000 --skip-file skipped-urls.txt

Crawling...

Stats:
  338440 links
    2041 destination URLs
    2297 URLs ignored
       0 warnings
       0 errors

[github-actions]

Bundle size comparison

Base commit: 7ab015c49deec84833cdfe1fb5e1606b901f6e81
Head commit: 0fcb05a547608f68d43ae0f968279bd79ec1865d

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