react-doctor/rn-list-data-mapped
Wrap the projection in `useMemo(() => items.map(...), [items])` so the list's `data` prop has a stable reference across parent renders
- Category: React Native
- Severity: warn
- Source:
oxlint-plugin-react-doctor - Framework: react-native
- Enabled when: framework=react-native and capabilities=react-native
Validation prompt
Use this to decide whether a fired diagnostic is real or a false positive.
Confirm the data prop on FlatList, FlashList, LegendList, SectionList, or VirtualizedList is an inline .map(...) or .filter(...) call — a fresh array per parent render busts referential equality and forces the list to re-key every row. False positive when the parent essentially never re-renders, but the useMemo fix is free.
Fix prompt
Use this once validation confirms the diagnostic is real.
Hoist the projection: const rows = useMemo(() => items.map(toRow), [items]) (or move the transform up to wherever items is fetched/derived), then pass data={rows}. Virtualization windows stop resetting and keyExtractor matching stays cheap across renders. See https://reactnative.dev/docs/optimizing-flatlist-configuration