Files
lodash/lodash.defaults/index.js
John-David Dalton c033f79116 Bump to v4.0.1.
2018-02-03 19:13:36 -08:00

120 lines
3.5 KiB
JavaScript

/**
* lodash (Custom Build) <https://lodash.com/>
* Build: `lodash modularize exports="npm" -o ./`
* Copyright 2012-2016 The Dojo Foundation <http://dojofoundation.org/>
* Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
* Copyright 2009-2016 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
* Available under MIT license <https://lodash.com/license>
*/
var assignInWith = require('lodash.assigninwith'),
rest = require('lodash.rest');
/**
* A faster alternative to `Function#apply`, this function invokes `func`
* with the `this` binding of `thisArg` and the arguments of `args`.
*
* @private
* @param {Function} func The function to invoke.
* @param {*} thisArg The `this` binding of `func`.
* @param {Array} args The arguments to invoke `func` with.
* @returns {*} Returns the result of `func`.
*/
function apply(func, thisArg, args) {
var length = args.length;
switch (length) {
case 0: return func.call(thisArg);
case 1: return func.call(thisArg, args[0]);
case 2: return func.call(thisArg, args[0], args[1]);
case 3: return func.call(thisArg, args[0], args[1], args[2]);
}
return func.apply(thisArg, args);
}
/** Used for built-in method references. */
var objectProto = Object.prototype;
/** Used to check objects for own properties. */
var hasOwnProperty = objectProto.hasOwnProperty;
/**
* Used by `_.defaults` to customize its `_.assignIn` use.
*
* @private
* @param {*} objValue The destination value.
* @param {*} srcValue The source value.
* @param {string} key The key of the property to assign.
* @param {Object} object The parent object of `objValue`.
* @returns {*} Returns the value to assign.
*/
function assignInDefaults(objValue, srcValue, key, object) {
if (objValue === undefined ||
(eq(objValue, objectProto[key]) && !hasOwnProperty.call(object, key))) {
return srcValue;
}
return objValue;
}
/**
* Performs a
* [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero)
* comparison between two values to determine if they are equivalent.
*
* @static
* @memberOf _
* @since 4.0.0
* @category Lang
* @param {*} value The value to compare.
* @param {*} other The other value to compare.
* @returns {boolean} Returns `true` if the values are equivalent, else `false`.
* @example
*
* var object = { 'user': 'fred' };
* var other = { 'user': 'fred' };
*
* _.eq(object, object);
* // => true
*
* _.eq(object, other);
* // => false
*
* _.eq('a', 'a');
* // => true
*
* _.eq('a', Object('a'));
* // => false
*
* _.eq(NaN, NaN);
* // => true
*/
function eq(value, other) {
return value === other || (value !== value && other !== other);
}
/**
* Assigns own and inherited enumerable string keyed properties of source
* objects to the destination object for all destination properties that
* resolve to `undefined`. Source objects are applied from left to right.
* Once a property is set, additional values of the same property are ignored.
*
* **Note:** This method mutates `object`.
*
* @static
* @since 0.1.0
* @memberOf _
* @category Object
* @param {Object} object The destination object.
* @param {...Object} [sources] The source objects.
* @returns {Object} Returns `object`.
* @see _.defaultsDeep
* @example
*
* _.defaults({ 'user': 'barney' }, { 'age': 36 }, { 'user': 'fred' });
* // => { 'user': 'barney', 'age': 36 }
*/
var defaults = rest(function(args) {
args.push(undefined, assignInDefaults);
return apply(assignInWith, undefined, args);
});
module.exports = defaults;