Because React handles setState
synchronously if it's called outside an event handler. Updating the state outside an event handler will force react to update the components synchronously, therefore adding the risk of encountering the zombie-child effect.
In order to fix this, the action needs to be wrapped in unstable_batchedUpdates
import { unstable_batchedUpdates } from 'react-dom' // or 'react-native'
const useFishStore = create((set) => ({
fishes: 0,
increaseFishes: () => set((prev) => ({ fishes: prev.fishes + 1 })),
}))
const nonReactCallback = () => {
unstable_batchedUpdates(() => {
useFishStore.getState().increaseFishes()
})
}
More details: pmndrs#302