basant307/AI_Governance_Project

1/*!2 * @description Recursive object extending3 * @author Viacheslav Lotsmanov <lotsmanov89@gmail.com>4 * @license MIT5 *6 * The MIT License (MIT)7 *8 * Copyright (c) 2013-2018 Viacheslav Lotsmanov9 *10 * Permission is hereby granted, free of charge, to any person obtaining a copy of11 * this software and associated documentation files (the "Software"), to deal in12 * the Software without restriction, including without limitation the rights to13 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of14 * the Software, and to permit persons to whom the Software is furnished to do so,15 * subject to the following conditions:16 *17 * The above copyright notice and this permission notice shall be included in all18 * copies or substantial portions of the Software.19 *20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS22 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR23 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER24 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN25 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.26 */27 28'use strict';29 30function isSpecificValue(val) {31	return (32		val instanceof Buffer33		|| val instanceof Date34		|| val instanceof RegExp35	) ? true : false;36}37 38function cloneSpecificValue(val) {39	if (val instanceof Buffer) {40		var x = Buffer.alloc41			? Buffer.alloc(val.length)42			: new Buffer(val.length);43		val.copy(x);44		return x;45	} else if (val instanceof Date) {46		return new Date(val.getTime());47	} else if (val instanceof RegExp) {48		return new RegExp(val);49	} else {50		throw new Error('Unexpected situation');51	}52}53 54/**55 * Recursive cloning array.56 */57function deepCloneArray(arr) {58	var clone = [];59	arr.forEach(function (item, index) {60		if (typeof item === 'object' && item !== null) {61			if (Array.isArray(item)) {62				clone[index] = deepCloneArray(item);63			} else if (isSpecificValue(item)) {64				clone[index] = cloneSpecificValue(item);65			} else {66				clone[index] = deepExtend({}, item);67			}68		} else {69			clone[index] = item;70		}71	});72	return clone;73}74 75function safeGetProperty(object, property) {76	return property === '__proto__' ? undefined : object[property];77}78 79/**80 * Extening object that entered in first argument.81 *82 * Returns extended object or false if have no target object or incorrect type.83 *84 * If you wish to clone source object (without modify it), just use empty new85 * object as first argument, like this:86 *   deepExtend({}, yourObj_1, [yourObj_N]);87 */88var deepExtend = module.exports = function (/*obj_1, [obj_2], [obj_N]*/) {89	if (arguments.length < 1 || typeof arguments[0] !== 'object') {90		return false;91	}92 93	if (arguments.length < 2) {94		return arguments[0];95	}96 97	var target = arguments[0];98 99	// convert arguments to array and cut off target object100	var args = Array.prototype.slice.call(arguments, 1);101 102	var val, src, clone;103 104	args.forEach(function (obj) {105		// skip argument if isn't an object, is null, or is an array106		if (typeof obj !== 'object' || obj === null || Array.isArray(obj)) {107			return;108		}109 110		Object.keys(obj).forEach(function (key) {111			src = safeGetProperty(target, key); // source value112			val = safeGetProperty(obj, key); // new value113 114			// recursion prevention115			if (val === target) {116				return;117 118			/**119			 * if new value isn't object then just overwrite by new value120			 * instead of extending.121			 */122			} else if (typeof val !== 'object' || val === null) {123				target[key] = val;124				return;125 126			// just clone arrays (and recursive clone objects inside)127			} else if (Array.isArray(val)) {128				target[key] = deepCloneArray(val);129				return;130 131			// custom cloning and overwrite for specific objects132			} else if (isSpecificValue(val)) {133				target[key] = cloneSpecificValue(val);134				return;135 136			// overwrite by new value if source isn't object or array137			} else if (typeof src !== 'object' || src === null || Array.isArray(src)) {138				target[key] = deepExtend({}, val);139				return;140 141			// source value and new value is objects both, extending...142			} else {143				target[key] = deepExtend(src, val);144				return;145			}146		});147	});148 149	return target;150};151