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Rule priority, scope & exceptions
Use this to align rules with the senior-level structure (P0/P1/P2, scope, exceptions/tradeoffs).
frontend ruleP1universalStack: React
reactstateimmutabilitycorrectness
Don't mutate the previous value inside a state updater; return a new one
Mutating prev (e.g. URLSearchParams) in a setState callback can cause stale state and missed re-renders. Copy it, then mutate the copy.
PR: hegnar-bellsheep-web · org-mining-hist-2026-06Created: Jun 18, 2026
Bad example
Old codets
| 1 | setSearchParams((prev) => { prev.set('sortBy', x); return prev; }); |
Explanation (EN)
Objašnjenje (HR)
Good example
New codets
| 1 | setSearchParams((prev) => { const next = new URLSearchParams(prev); next.set('sortBy', x); return next; }); |
Explanation (EN)
Objašnjenje (HR)