useSpecialEffect Implementation

useSpecialEffect.ts

import React from "react";

export default function useSpecialEffect(
    callback: (prevRef: any) => any,
    updatables: any = {} // Passing false here means the effect will only run once. Like passing [] to useEffect()
): void {
    const prevRef = React.useRef<any>({});
    const renderCountRef = React.useRef<number>(0);

    prevRef.current.update = (propertyString: string, value: any) => {
        if (!(propertyString in prevRef.current)) {
            prevRef.current[propertyString] = null;
        }
        prevRef.current[propertyString] = value;
    };

    prevRef.current.hasChanged = (...args: any) => {
        const hasAnythingChanged: boolean[] = args.map((check: any) => {
            if (check instanceof Array) {
                return !Object.is(check[0], check[1]);
            }
            else {
                for (let p in check) {
                    if (!(p in prevRef.current)) { 
                        if (renderCountRef.current > 1) {
                            throw new Error(`useSpecialEffect() -> Looks like you are missing updatable "${p}". Please remove it from .hasChanged() or add it to the updatables object. For example: useSpecialEffect(..., {${p}, ...})`);
                        }
                        return true;
                    }
                    return !Object.is(prevRef.current[p], check[p]);
                }
                return false;
            }
        });
        let i = 0;
        while (i < hasAnythingChanged.length) {
            if (hasAnythingChanged[i]) {
                return true;
            }
            i++;
        }
        return false;
    };

    React.useEffect(() => {
        // console.log(callback.toString());
        const cleanUp = callback(prevRef.current);
        for (let p in updatables) {
            prevRef.current.update(p, updatables[p]);
        }
        renderCountRef.current++;
        return cleanUp;
        // eslint-disable-next-line react-hooks/exhaustive-deps
    }, ((updatables === false) ? [] : undefined));
}