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/**
* Lo-Dash 2.4.1 (Custom Build) <http://lodash.com/>
* Build: `lodash modularize exports="node" -o ./compat/`
* Copyright 2012-2013 The Dojo Foundation <http://dojofoundation.org/>
* Based on Underscore.js 1.5.2 <http://underscorejs.org/LICENSE>
* Copyright 2009-2013 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
* Available under MIT license <http://lodash.com/license>
*/
var compareAscending = require('../internals/compareAscending'),
createCallback = require('../functions/createCallback'),
forEach = require('./forEach'),
getArray = require('../internals/getArray'),
getObject = require('../internals/getObject'),
isArray = require('../objects/isArray'),
map = require('./map'),
releaseArray = require('../internals/releaseArray'),
releaseObject = require('../internals/releaseObject');
/**
* Creates an array of elements, sorted in ascending order by the results of
* running each element in a collection through the callback. This method
* performs a stable sort, that is, it will preserve the original sort order
* of equal elements. The callback is bound to `thisArg` and invoked with
* three arguments; (value, index|key, collection).
*
* If a property name is provided for `callback` the created "_.pluck" style
* callback will return the property value of the given element.
*
* If an array of property names is provided for `callback` the collection
* will be sorted by each property value.
*
* If an object is provided for `callback` the created "_.where" style callback
* will return `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @category Collections
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Array|Function|Object|string} [callback=identity] The function called
* per iteration. If a property name or object is provided it will be used
* to create a "_.pluck" or "_.where" style callback, respectively.
* @param {*} [thisArg] The `this` binding of `callback`.
* @returns {Array} Returns a new array of sorted elements.
* @example
*
* _.sortBy([1, 2, 3], function(num) { return Math.sin(num); });
* // => [3, 1, 2]
*
* _.sortBy([1, 2, 3], function(num) { return this.sin(num); }, Math);
* // => [3, 1, 2]
*
* var characters = [
* { 'name': 'barney', 'age': 36 },
* { 'name': 'fred', 'age': 40 },
* { 'name': 'barney', 'age': 26 },
* { 'name': 'fred', 'age': 30 }
* ];
*
* // using "_.pluck" callback shorthand
* _.map(_.sortBy(characters, 'age'), _.values);
* // => [['barney', 26], ['fred', 30], ['barney', 36], ['fred', 40]]
*
* // sorting by multiple properties
* _.map(_.sortBy(characters, ['name', 'age']), _.values);
* // = > [['barney', 26], ['barney', 36], ['fred', 30], ['fred', 40]]
*/
function sortBy(collection, callback, thisArg) {
var index = -1,
isArr = isArray(callback),
length = collection ? collection.length : 0,
result = Array(typeof length == 'number' ? length : 0);
if (!isArr) {
callback = createCallback(callback, thisArg, 3);
}
forEach(collection, function(value, key, collection) {
var object = result[++index] = getObject();
if (isArr) {
object.criteria = map(callback, function(key) { return value[key]; });
} else {
(object.criteria = getArray())[0] = callback(value, key, collection);
}
object.index = index;
object.value = value;
});
length = result.length;
result.sort(compareAscending);
while (length--) {
var object = result[length];
result[length] = object.value;
if (!isArr) {
releaseArray(object.criteria);
}
releaseObject(object);
}
return result;
}
module.exports = sortBy;