Deep Clone (Time Limit 1h)

clone.js

function clone(target, options = {}) {
    options = Object.assign({ omitTypes: [], maxDepth: 10 }, options);
    const parents = [];
    const copiedParents = [];
    const complexTypes = [Boolean, Number, String, Date, Error, Map, Set, RegExp];
    const skippedTypes = [Symbol, Function];

    function cloneLayer(obj, layer = 0) {
        // Simple/complex types
        if (obj === null) return null;
        if (obj === undefined) return undefined;
        if (Array.isArray(obj)) return Array.from(obj);
        if (complexTypes.includes(obj.constructor)) return new obj.constructor(obj);
        if (skippedTypes.includes(obj.constructor)) return obj;
        
        // Recursive associations
        for (let i = 0; i < parents.length; i++) {
            if (Object.is(parents[i], obj)) return copiedParents[i];
        }

        if (layer >= options.maxDepth) return {};

        // Object types
        parents.push(obj);
        const copy = {};
        copiedParents.push(copy);
        for (let i in obj) {
            if (obj.hasOwnProperty(i)) { 
                if (obj[i] !== null && !options.omitTypes.includes(obj[i].constructor)) {
                    copy[i] = cloneLayer(obj[i], layer + 1);
                }
            }
        }
        
        return copy;
    }

    return cloneLayer(target);
}