[alexcarpenter]

Description

Types machine state names in the Mosaic machine lib. Runtime behavior does not change.

• For machines built with setup().createMachine, TStates is inferred from the states keys, so snapshot.value is the union of state names instead of string, and initial plus every transition target are checked against those names.
• StateMachine, Snapshot, Actor and CreateActorOptions take a TStates param, threaded through createActor, mockActor, useMachine, useActor and useSelector. It defaults to string everywhere, so callers that pass explicit type arguments still compile.
• initial and targets are wrapped in NoInfer, so a bare createMachine({ initial: 'a', states: { a: { on: { NEXT: 'b' } }, b: {} } }) no longer infers TStates from initial and rejects the valid target 'b'.
• The actor internals now carry TStates, which removes two as string casts in create-actor.ts (suppression count 8 → 6).

No existing machine needed changes to typecheck. The machine lib is not part of @clerk/mosaic's public exports, so this has an empty changeset.

Checklist

• pnpm test runs as expected.
• pnpm build runs as expected.
• (If applicable) JSDoc comments have been added or updated for any package exports
• (If applicable) Documentation has been updated

Type of change

• 🐛 Bug fix
• 🌟 New feature
• 🔨 Breaking change
• 📖 Refactoring / dependency upgrade / documentation
• other:

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[changeset-bot]

🦋 Changeset detected

Latest commit: b94f92f

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 0 packages

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No actionable comments were generated in the recent review.

Recent review info

Run configuration

• Source mode: Auto
• Repository: clerk/javascript
• Branch: carp/mosaic-machine-state-names
• File: .coderabbit.yaml
• Commit: b94f92f
• Layers: Repository YAML (base), Organization UI (inherited)
• Review profile: ASSERTIVE
• Plan: Team
• Run ID: d8463264-0090-4ebb-98ed-0af49a60819d

Commits

Reviewing files that changed from the base of the PR and between cb8638a and b94f92f.

Files selected for processing: 8

• .changeset/mosaic-machine-state-names.md
• packages/mosaic/eslint-suppressions.json
• packages/mosaic/src/machine/create-actor.ts
• packages/mosaic/src/machine/create-machine.ts
• packages/mosaic/src/machine/setup.ts
• packages/mosaic/src/machine/types.test-d.ts
• packages/mosaic/src/machine/types.ts
• packages/mosaic/src/machine/use-machine.ts

Linked repositories identified

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• clerk/clerk_go (manual)
• clerk/dashboard (manual)
• clerk/accounts (manual)
• clerk/backoffice (manual)
• clerk/clerk (manual)
• clerk/clerk-docs (manual)
• clerk/cloudflare-workers (manual)
• clerk/clerk-android (auto-detected)
• clerk/clerk-ios (auto-detected)
• clerk/cli (auto-detected)

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Walkthrough

Machine state-name types now flow from configuration through machine creation, actors, snapshots, and hooks. Transition targets and actor snapshots use the configured state-name type. Type tests cover inferred state-name unions and reject invalid initial states, transition targets, and snapshot values. The changeset file gains empty YAML frontmatter, and the lint suppression count decreases.

Priority: Low

Estimated code review effort: 3 (Moderate) | ~25 minutes

Suggested reviewers: ephem

Merge Risk: Minimal · up to b94f9

No confirmed issue prevents merging after normal checks.

Pre-merge checks: 5

Check name	Status	Explanation
Title check		The title clearly and concisely describes the main changes: adding machine state-name typing and validating transition targets in setup machines.
Description check		The description directly explains the state-name typing changes, target validation, affected APIs, compatibility behavior, and verification steps.
Docstring Coverage		Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff with cyclomatic complexity of at least 2. Documentat…
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

Full details: Docstring Coverage

Explanation

Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff with cyclomatic complexity of at least 2. Documentation-only edits and deletions within surviving functions are included; unchanged diff context and fully deleted functions are excluded. Analyzed 6 functions across 6 files. (2 skipped: 2 unsupported.)

• Autofix · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

Warning

Linked repositories: Some configured repositories could not be included in this review. Cross-repository analysis may be incomplete. Please check linked-repository access and settings.

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commit: b94f92f