hd-utils/lib/utils/functions/createWatcher.js

A handy utils for modern JS developers

/**
 * @description will call the passed object whenever the returned object is changed and will pass the prev and the current object.
 * @example const watchedObject = createWatcher({ name: 'John', age: 25 }, (prev, current) => {
  console.log('Object changed:', prev, '->', current);
});
watchedObject.age = 30;

// to unwatch
const prototype = Object.getPrototypeOf(watchedObject);
console.log(prototype.unwatch()) // or just watchedObject.__prototype__.unwatch();

 */
export default function createWatcher(target, callback) {
    let watch = true;
    return new Proxy(target, {
        set: (obj, prop, value) => {
            const prevValue = { ...obj };
            obj[prop] = value;
            Object.setPrototypeOf(obj, {
                unwatch: function () {
                    watch = false;
                },
            });
            watch && callback(prevValue, { ...obj });
            return true;
        },
    });
}