clone.js
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/* eslint-disable */
var clone = (function() {
'use strict';
function _instanceof(obj, type) {
return type != null && obj instanceof type;
}
var nativeMap;
try {
nativeMap = Map;
} catch(_) {
// maybe a reference error because no `Map`. Give it a dummy value that no
// value will ever be an instanceof.
nativeMap = function() {};
}
var nativeSet;
try {
nativeSet = Set;
} catch(_) {
nativeSet = function() {};
}
var nativePromise;
try {
nativePromise = Promise;
} catch(_) {
nativePromise = function() {};
}
/**
* Clones (copies) an Object using deep copying.
*
* This function supports circular references by default, but if you are certain
* there are no circular references in your object, you can save some CPU time
* by calling clone(obj, false).
*
* Caution: if `circular` is false and `parent` contains circular references,
* your program may enter an infinite loop and crash.
*
* @param `parent` - the object to be cloned
* @param `circular` - set to true if the object to be cloned may contain
* circular references. (optional - true by default)
* @param `depth` - set to a number if the object is only to be cloned to
* a particular depth. (optional - defaults to Infinity)
* @param `prototype` - sets the prototype to be used when cloning an object.
* (optional - defaults to parent prototype).
* @param `includeNonEnumerable` - set to true if the non-enumerable properties
* should be cloned as well. Non-enumerable properties on the prototype
* chain will be ignored. (optional - false by default)
*/
function clone(parent, circular, depth, prototype, includeNonEnumerable) {
if (typeof circular === 'object') {
depth = circular.depth;
prototype = circular.prototype;
includeNonEnumerable = circular.includeNonEnumerable;
circular = circular.circular;
}
// maintain two arrays for circular references, where corresponding parents
// and children have the same index
var allParents = [];
var allChildren = [];
var useBuffer = typeof Buffer != 'undefined';
if (typeof circular == 'undefined')
circular = true;
if (typeof depth == 'undefined')
depth = Infinity;
// recurse this function so we don't reset allParents and allChildren
function _clone(parent, depth) {
// cloning null always returns null
if (parent === null)
return null;
if (depth === 0)
return parent;
var child;
var proto;
if (typeof parent != 'object') {
return parent;
}
if (_instanceof(parent, nativeMap)) {
child = new nativeMap();
} else if (_instanceof(parent, nativeSet)) {
child = new nativeSet();
} else if (_instanceof(parent, nativePromise)) {
child = new nativePromise(function (resolve, reject) {
parent.then(function(value) {
resolve(_clone(value, depth - 1));
}, function(err) {
reject(_clone(err, depth - 1));
});
});
} else if (clone.__isArray(parent)) {
child = [];
} else if (clone.__isRegExp(parent)) {
child = new RegExp(parent.source, __getRegExpFlags(parent));
if (parent.lastIndex) child.lastIndex = parent.lastIndex;
} else if (clone.__isDate(parent)) {
child = new Date(parent.getTime());
} else if (useBuffer && Buffer.isBuffer(parent)) {
if (Buffer.from) {
// Node.js >= 5.10.0
child = Buffer.from(parent);
} else {
// Older Node.js versions
child = new Buffer(parent.length);
parent.copy(child);
}
return child;
} else if (_instanceof(parent, Error)) {
child = Object.create(parent);
} else {
if (typeof prototype == 'undefined') {
proto = Object.getPrototypeOf(parent);
child = Object.create(proto);
}
else {
child = Object.create(prototype);
proto = prototype;
}
}
if (circular) {
var index = allParents.indexOf(parent);
if (index != -1) {
return allChildren[index];
}
allParents.push(parent);
allChildren.push(child);
}
if (_instanceof(parent, nativeMap)) {
parent.forEach(function(value, key) {
var keyChild = _clone(key, depth - 1);
var valueChild = _clone(value, depth - 1);
child.set(keyChild, valueChild);
});
}
if (_instanceof(parent, nativeSet)) {
parent.forEach(function(value) {
var entryChild = _clone(value, depth - 1);
child.add(entryChild);
});
}
for (var i in parent) {
var attrs = Object.getOwnPropertyDescriptor(parent, i);
if (attrs) {
child[i] = _clone(parent[i], depth - 1);
}
try {
var objProperty = Object.getOwnPropertyDescriptor(parent, i);
if (objProperty.set === 'undefined') {
// no setter defined. Skip cloning this property
continue;
}
child[i] = _clone(parent[i], depth - 1);
} catch(e){
if (e instanceof TypeError) {
// when in strict mode, TypeError will be thrown if child[i] property only has a getter
// we can't do anything about this, other than inform the user that this property cannot be set.
continue
} else if (e instanceof ReferenceError) {
//this may happen in non strict mode
continue
}
}
}
if (Object.getOwnPropertySymbols) {
var symbols = Object.getOwnPropertySymbols(parent);
for (var i = 0; i < symbols.length; i++) {
// Don't need to worry about cloning a symbol because it is a primitive,
// like a number or string.
var symbol = symbols[i];
var descriptor = Object.getOwnPropertyDescriptor(parent, symbol);
if (descriptor && !descriptor.enumerable && !includeNonEnumerable) {
continue;
}
child[symbol] = _clone(parent[symbol], depth - 1);
Object.defineProperty(child, symbol, descriptor);
}
}
if (includeNonEnumerable) {
var allPropertyNames = Object.getOwnPropertyNames(parent);
for (var i = 0; i < allPropertyNames.length; i++) {
var propertyName = allPropertyNames[i];
var descriptor = Object.getOwnPropertyDescriptor(parent, propertyName);
if (descriptor && descriptor.enumerable) {
continue;
}
child[propertyName] = _clone(parent[propertyName], depth - 1);
Object.defineProperty(child, propertyName, descriptor);
}
}
return child;
}
return _clone(parent, depth);
}
/**
* Simple flat clone using prototype, accepts only objects, usefull for property
* override on FLAT configuration object (no nested props).
*
* USE WITH CAUTION! This may not behave as you wish if you do not know how this
* works.
*/
clone.clonePrototype = function clonePrototype(parent) {
if (parent === null)
return null;
var c = function () {};
c.prototype = parent;
return new c();
};
// private utility functions
function __objToStr(o) {
return Object.prototype.toString.call(o);
}
clone.__objToStr = __objToStr;
function __isDate(o) {
return typeof o === 'object' && __objToStr(o) === '[object Date]';
}
clone.__isDate = __isDate;
function __isArray(o) {
return typeof o === 'object' && __objToStr(o) === '[object Array]';
}
clone.__isArray = __isArray;
function __isRegExp(o) {
return typeof o === 'object' && __objToStr(o) === '[object RegExp]';
}
clone.__isRegExp = __isRegExp;
function __getRegExpFlags(re) {
var flags = '';
if (re.global) flags += 'g';
if (re.ignoreCase) flags += 'i';
if (re.multiline) flags += 'm';
return flags;
}
clone.__getRegExpFlags = __getRegExpFlags;
return clone;
})();
export default clone