var arrayCopy = require('./arrayCopy'), arrayEach = require('./arrayEach'), baseAssign = require('./baseAssign'), baseForOwn = require('./baseForOwn'), initCloneArray = require('./initCloneArray'), initCloneByTag = require('./initCloneByTag'), initCloneObject = require('./initCloneObject'), isArray = require('../lang/isArray'), isObject = require('../lang/isObject'); /** `Object#toString` result references. */ var argsTag = '[object Arguments]', arrayTag = '[object Array]', boolTag = '[object Boolean]', dateTag = '[object Date]', errorTag = '[object Error]', funcTag = '[object Function]', mapTag = '[object Map]', numberTag = '[object Number]', objectTag = '[object Object]', regexpTag = '[object RegExp]', setTag = '[object Set]', stringTag = '[object String]', weakMapTag = '[object WeakMap]'; var arrayBufferTag = '[object ArrayBuffer]', float32Tag = '[object Float32Array]', float64Tag = '[object Float64Array]', int8Tag = '[object Int8Array]', int16Tag = '[object Int16Array]', int32Tag = '[object Int32Array]', uint8Tag = '[object Uint8Array]', uint8ClampedTag = '[object Uint8ClampedArray]', uint16Tag = '[object Uint16Array]', uint32Tag = '[object Uint32Array]'; /** Used to identify `toStringTag` values supported by `_.clone`. */ var cloneableTags = {}; cloneableTags[argsTag] = cloneableTags[arrayTag] = cloneableTags[arrayBufferTag] = cloneableTags[boolTag] = cloneableTags[dateTag] = cloneableTags[float32Tag] = cloneableTags[float64Tag] = cloneableTags[int8Tag] = cloneableTags[int16Tag] = cloneableTags[int32Tag] = cloneableTags[numberTag] = cloneableTags[objectTag] = cloneableTags[regexpTag] = cloneableTags[stringTag] = cloneableTags[uint8Tag] = cloneableTags[uint8ClampedTag] = cloneableTags[uint16Tag] = cloneableTags[uint32Tag] = true; cloneableTags[errorTag] = cloneableTags[funcTag] = cloneableTags[mapTag] = cloneableTags[setTag] = cloneableTags[weakMapTag] = false; /** Used for native method references. */ var objectProto = Object.prototype; /** * Used to resolve the [`toStringTag`](http://ecma-international.org/ecma-262/6.0/#sec-object.prototype.tostring) * of values. */ var objToString = objectProto.toString; /** * The base implementation of `_.clone` without support for argument juggling * and `this` binding `customizer` functions. * * @private * @param {*} value The value to clone. * @param {boolean} [isDeep] Specify a deep clone. * @param {Function} [customizer] The function to customize cloning values. * @param {string} [key] The key of `value`. * @param {Object} [object] The object `value` belongs to. * @param {Array} [stackA=[]] Tracks traversed source objects. * @param {Array} [stackB=[]] Associates clones with source counterparts. * @returns {*} Returns the cloned value. */ function baseClone(value, isDeep, customizer, key, object, stackA, stackB) { var result; if (customizer) { result = object ? customizer(value, key, object) : customizer(value); } if (result !== undefined) { return result; } if (!isObject(value)) { return value; } var isArr = isArray(value); if (isArr) { result = initCloneArray(value); if (!isDeep) { return arrayCopy(value, result); } } else { var tag = objToString.call(value), isFunc = tag == funcTag; if (tag == objectTag || tag == argsTag || (isFunc && !object)) { result = initCloneObject(isFunc ? {} : value); if (!isDeep) { return baseAssign(result, value); } } else { return cloneableTags[tag] ? initCloneByTag(value, tag, isDeep) : (object ? value : {}); } } // Check for circular references and return its corresponding clone. stackA || (stackA = []); stackB || (stackB = []); var length = stackA.length; while (length--) { if (stackA[length] == value) { return stackB[length]; } } // Add the source value to the stack of traversed objects and associate it with its clone. stackA.push(value); stackB.push(result); // Recursively populate clone (susceptible to call stack limits). (isArr ? arrayEach : baseForOwn)(value, function(subValue, key) { result[key] = baseClone(subValue, isDeep, customizer, key, value, stackA, stackB); }); return result; } module.exports = baseClone;