Fix re-rendering when another component reuses the same query #3195
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Summary
When component A uses
useQuery
and has already loaded a result and then component B mounts and uses the same query, it currently causes component A to re-render becauseoperation
is not shallowly equal even though nothing about the result is changing.This is a performance issue because it causes unnecessary re-renders.
It also can cause an infinite render loop with lazily loaded components because it can trigger a state update further up the tree during the initial render of the lazily loaded component which makes React back out of the render (which happened in my application, although I've had trouble creating a minimal reproduction). This issue is resolved with this change in my application.
Set of changes
isShallowDifferent
foroperation
where it checks the operation key if theoperation
s are not equalCONTRIBUTING.md