1 | 'use strict';
|
---|
2 |
|
---|
3 | var hasOwn = Object.prototype.hasOwnProperty;
|
---|
4 | var toStr = Object.prototype.toString;
|
---|
5 | var defineProperty = Object.defineProperty;
|
---|
6 | var gOPD = Object.getOwnPropertyDescriptor;
|
---|
7 |
|
---|
8 | var isArray = function isArray(arr) {
|
---|
9 | if (typeof Array.isArray === 'function') {
|
---|
10 | return Array.isArray(arr);
|
---|
11 | }
|
---|
12 |
|
---|
13 | return toStr.call(arr) === '[object Array]';
|
---|
14 | };
|
---|
15 |
|
---|
16 | var isPlainObject = function isPlainObject(obj) {
|
---|
17 | if (!obj || toStr.call(obj) !== '[object Object]') {
|
---|
18 | return false;
|
---|
19 | }
|
---|
20 |
|
---|
21 | var hasOwnConstructor = hasOwn.call(obj, 'constructor');
|
---|
22 | var hasIsPrototypeOf = obj.constructor && obj.constructor.prototype && hasOwn.call(obj.constructor.prototype, 'isPrototypeOf');
|
---|
23 | // Not own constructor property must be Object
|
---|
24 | if (obj.constructor && !hasOwnConstructor && !hasIsPrototypeOf) {
|
---|
25 | return false;
|
---|
26 | }
|
---|
27 |
|
---|
28 | // Own properties are enumerated firstly, so to speed up,
|
---|
29 | // if last one is own, then all properties are own.
|
---|
30 | var key;
|
---|
31 | for (key in obj) { /**/ }
|
---|
32 |
|
---|
33 | return typeof key === 'undefined' || hasOwn.call(obj, key);
|
---|
34 | };
|
---|
35 |
|
---|
36 | // If name is '__proto__', and Object.defineProperty is available, define __proto__ as an own property on target
|
---|
37 | var setProperty = function setProperty(target, options) {
|
---|
38 | if (defineProperty && options.name === '__proto__') {
|
---|
39 | defineProperty(target, options.name, {
|
---|
40 | enumerable: true,
|
---|
41 | configurable: true,
|
---|
42 | value: options.newValue,
|
---|
43 | writable: true
|
---|
44 | });
|
---|
45 | } else {
|
---|
46 | target[options.name] = options.newValue;
|
---|
47 | }
|
---|
48 | };
|
---|
49 |
|
---|
50 | // Return undefined instead of __proto__ if '__proto__' is not an own property
|
---|
51 | var getProperty = function getProperty(obj, name) {
|
---|
52 | if (name === '__proto__') {
|
---|
53 | if (!hasOwn.call(obj, name)) {
|
---|
54 | return void 0;
|
---|
55 | } else if (gOPD) {
|
---|
56 | // In early versions of node, obj['__proto__'] is buggy when obj has
|
---|
57 | // __proto__ as an own property. Object.getOwnPropertyDescriptor() works.
|
---|
58 | return gOPD(obj, name).value;
|
---|
59 | }
|
---|
60 | }
|
---|
61 |
|
---|
62 | return obj[name];
|
---|
63 | };
|
---|
64 |
|
---|
65 | module.exports = function extend() {
|
---|
66 | var options, name, src, copy, copyIsArray, clone;
|
---|
67 | var target = arguments[0];
|
---|
68 | var i = 1;
|
---|
69 | var length = arguments.length;
|
---|
70 | var deep = false;
|
---|
71 |
|
---|
72 | // Handle a deep copy situation
|
---|
73 | if (typeof target === 'boolean') {
|
---|
74 | deep = target;
|
---|
75 | target = arguments[1] || {};
|
---|
76 | // skip the boolean and the target
|
---|
77 | i = 2;
|
---|
78 | }
|
---|
79 | if (target == null || (typeof target !== 'object' && typeof target !== 'function')) {
|
---|
80 | target = {};
|
---|
81 | }
|
---|
82 |
|
---|
83 | for (; i < length; ++i) {
|
---|
84 | options = arguments[i];
|
---|
85 | // Only deal with non-null/undefined values
|
---|
86 | if (options != null) {
|
---|
87 | // Extend the base object
|
---|
88 | for (name in options) {
|
---|
89 | src = getProperty(target, name);
|
---|
90 | copy = getProperty(options, name);
|
---|
91 |
|
---|
92 | // Prevent never-ending loop
|
---|
93 | if (target !== copy) {
|
---|
94 | // Recurse if we're merging plain objects or arrays
|
---|
95 | if (deep && copy && (isPlainObject(copy) || (copyIsArray = isArray(copy)))) {
|
---|
96 | if (copyIsArray) {
|
---|
97 | copyIsArray = false;
|
---|
98 | clone = src && isArray(src) ? src : [];
|
---|
99 | } else {
|
---|
100 | clone = src && isPlainObject(src) ? src : {};
|
---|
101 | }
|
---|
102 |
|
---|
103 | // Never move original objects, clone them
|
---|
104 | setProperty(target, { name: name, newValue: extend(deep, clone, copy) });
|
---|
105 |
|
---|
106 | // Don't bring in undefined values
|
---|
107 | } else if (typeof copy !== 'undefined') {
|
---|
108 | setProperty(target, { name: name, newValue: copy });
|
---|
109 | }
|
---|
110 | }
|
---|
111 | }
|
---|
112 | }
|
---|
113 | }
|
---|
114 |
|
---|
115 | // Return the modified object
|
---|
116 | return target;
|
---|
117 | };
|
---|