import { useContext, useDebugValue } from 'react';
import { useReduxContext as useDefaultReduxContext } from './useReduxContext';
import { ReactReduxContext } from '../components/Context';
import { notInitialized } from '../utils/useSyncExternalStore';
let useSyncExternalStoreWithSelector = notInitialized;
export const initializeUseSelector = fn => {
useSyncExternalStoreWithSelector = fn;
};
const refEquality = (a, b) => a === b;
/**
* Hook factory, which creates a `useSelector` hook bound to a given context.
*
* @param {React.Context} [context=ReactReduxContext] Context passed to your `<Provider>`.
* @returns {Function} A `useSelector` hook bound to the specified context.
*/
export function createSelectorHook(context = ReactReduxContext) {
const useReduxContext = context === ReactReduxContext ? useDefaultReduxContext : () => useContext(context);
return function useSelector(selector, equalityFn = refEquality) {
if (process.env.NODE_ENV !== 'production') {
if (!selector) {
throw new Error(`You must pass a selector to useSelector`);
}
if (typeof selector !== 'function') {
throw new Error(`You must pass a function as a selector to useSelector`);
}
if (typeof equalityFn !== 'function') {
throw new Error(`You must pass a function as an equality function to useSelector`);
}
}
const {
store,
subscription,
getServerState
} = useReduxContext();
const selectedState = useSyncExternalStoreWithSelector(subscription.addNestedSub, store.getState, getServerState || store.getState, selector, equalityFn);
useDebugValue(selectedState);
return selectedState;
};
}
/**
* A hook to access the redux store's state. This hook takes a selector function
* as an argument. The selector is called with the store state.
*
* This hook takes an optional equality comparison function as the second parameter
* that allows you to customize the way the selected state is compared to determine
* whether the component needs to be re-rendered.
*
* @param {Function} selector the selector function
* @param {Function=} equalityFn the function that will be used to determine equality
*
* @returns {any} the selected state
*
* @example
*
* import React from 'react'
* import { useSelector } from 'react-redux'
*
* export const CounterComponent = () => {
* const counter = useSelector(state => state.counter)
* return <div>{counter}</div>
* }
*/
export const useSelector = /*#__PURE__*/createSelectorHook();