Find Predicate Bugs
Find Predicate Bugs
A find callback should test each item and return a boolean-like answer. If the predicate accidentally assigns to a property, the search can appear to work while corrupting the records it inspected.
That mistake is especially risky in lookup helpers because they are called from many places. A correct lookup returns the matching record, leaves every record unchanged, and gives a clear fallback when nothing matches.
Your task: Fix getUserById so it returns the user with the requested id. Return null when no user matches, and do not mutate any user object.
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Find Predicate Bugs
A find callback should test each item and return a boolean-like answer. If the predicate accidentally assigns to a property, the search can appear to work while corrupting the records it inspected.
That mistake is especially risky in lookup helpers because they are called from many places. A correct lookup returns the matching record, leaves every record unchanged, and gives a clear fallback when nothing matches.
Your task: Fix getUserById so it returns the user with the requested id. Return null when no user matches, and do not mutate any user object.