1
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var baseRest = require('./_baseRest'),
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2
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eq = require('./eq'),
|
3
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isIterateeCall = require('./_isIterateeCall'),
|
4
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keysIn = require('./keysIn');
|
5
|
|
6
|
/** Used for built-in method references. */
|
7
|
var objectProto = Object.prototype;
|
8
|
|
9
|
/** Used to check objects for own properties. */
|
10
|
var hasOwnProperty = objectProto.hasOwnProperty;
|
11
|
|
12
|
/**
|
13
|
* Assigns own and inherited enumerable string keyed properties of source
|
14
|
* objects to the destination object for all destination properties that
|
15
|
* resolve to `undefined`. Source objects are applied from left to right.
|
16
|
* Once a property is set, additional values of the same property are ignored.
|
17
|
*
|
18
|
* **Note:** This method mutates `object`.
|
19
|
*
|
20
|
* @static
|
21
|
* @since 0.1.0
|
22
|
* @memberOf _
|
23
|
* @category Object
|
24
|
* @param {Object} object The destination object.
|
25
|
* @param {...Object} [sources] The source objects.
|
26
|
* @returns {Object} Returns `object`.
|
27
|
* @see _.defaultsDeep
|
28
|
* @example
|
29
|
*
|
30
|
* _.defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
|
31
|
* // => { 'a': 1, 'b': 2 }
|
32
|
*/
|
33
|
var defaults = baseRest(function(object, sources) {
|
34
|
object = Object(object);
|
35
|
|
36
|
var index = -1;
|
37
|
var length = sources.length;
|
38
|
var guard = length > 2 ? sources[2] : undefined;
|
39
|
|
40
|
if (guard && isIterateeCall(sources[0], sources[1], guard)) {
|
41
|
length = 1;
|
42
|
}
|
43
|
|
44
|
while (++index < length) {
|
45
|
var source = sources[index];
|
46
|
var props = keysIn(source);
|
47
|
var propsIndex = -1;
|
48
|
var propsLength = props.length;
|
49
|
|
50
|
while (++propsIndex < propsLength) {
|
51
|
var key = props[propsIndex];
|
52
|
var value = object[key];
|
53
|
|
54
|
if (value === undefined ||
|
55
|
(eq(value, objectProto[key]) && !hasOwnProperty.call(object, key))) {
|
56
|
object[key] = source[key];
|
57
|
}
|
58
|
}
|
59
|
}
|
60
|
|
61
|
return object;
|
62
|
});
|
63
|
|
64
|
module.exports = defaults;
|