react-firehooks/lib/internal/useLoadingValue.js

Lightweight dependency-free collection of React hooks for Firebase

import { useCallback, useMemo, useState } from "react";
export const LoadingState = Symbol();
/**
 * @internal
 */
export function useLoadingValue(initialState) {
    const [state, setState] = useState({
        error: undefined,
        loading: initialState === LoadingState ? true : false,
        value: initialState === LoadingState ? undefined : initialState,
    });
    const setValue = useCallback((value) => {
        setState({
            value,
            loading: false,
            error: undefined,
        });
    }, []);
    const setLoading = useCallback(() => {
        setState({
            value: undefined,
            loading: true,
            error: undefined,
        });
    }, []);
    const setError = useCallback((error) => {
        setState({
            value: undefined,
            loading: false,
            error,
        });
    }, []);
    return useMemo(() => ({
        value: state.value,
        setValue,
        loading: state.loading,
        setLoading,
        error: state.error,
        setError,
    }), [state, setValue, setLoading, setError]);
}