react-hooks-js/set-state-in-render

Validates against setting state during render, which can trigger additional renders and potential infinite render loops

Validation prompt

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

Fires on UNCONDITIONAL setState during render: guaranteed infinite loop. The conditional sync-state-to-prop pattern (if (items !== prevItems) { setPrevItems(items); setSelection(null); }) is explicitly allowed and is the documented escape hatch.

Suppress when: rare; bare setState in the component body is almost always a real bug.

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.

Move the setState into an event handler (onClick, onChange, onSubmit) or into useEffect if it must run after commit. To synchronize state with a prop change across renders, use the gated pattern above: store the previous prop in state and only call setState when it differs. For clamping or derived values, derive during render instead of mirroring into state. See https://react.dev/reference/eslint-plugin-react-hooks/lints/set-state-in-render

Repository-wide copy prompt

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