react-doctor/no-chain-state-updates

Disallow chaining state changes in an effect.

Validation prompt

Confirm the detector match and collect the required evidence before deciding whether an edit is warranted.

Fires on a cleanup-less useEffect or useLayoutEffect whose dependencies include state and which synchronously updates other state from unrelated data. It follows React imports, namespace calls, exact aliases, and semantic or isomorphic aliases that select between effect hooks. It excludes convergent previous/current snapshot guards, externally driven state, external-system synchronization, and state that must read committed Document Object Model (DOM) state. React 18 projects are excluded because this rule is disabled when the supported React range includes 18.

Evidence boundary

The diagnostic proves only that the detector’s modeled source pattern matched. It does not prove runtime impact, product intent, rendered failure, or that one remediation is correct.

Establish the environment, repository policy, exceptions, and required rendered or runtime evidence before deciding the occurrence.

Record one outcome:

• Confirmed failure: The required evidence establishes the violation.
• Rejected: A documented exception or false-positive predicate applies.
• Needs evidence: Named evidence can still be collected.
• Unavailable: Required evidence cannot be collected in this run.
• Waived with evidence: An authorized, scoped exception applies to an established failure.
• Observation: The review records an optional tradeoff without claiming a defect.

A waiver records its scope, authority, evidence, and review condition. It is not a pass or false positive.

Default severity is registry metadata. Use the occurrence’s JSON severity after repository configuration when ordering real findings.

Fix prompt

Apply this candidate correction only after the required evidence confirms the risk.

Compute both values in the event handler that updates the upstream state, then call both setters so React batches one render. Remove the second state variable when it always derives from the first, and compute it during render or with useMemo. See https://react.dev/learn/you-might-not-need-an-effect#chains-of-computations

Repository-wide copy prompt

Use this repository-wide prompt only after validating each occurrence. For one occurrence, use the guidance above.