1: <?php
 2: /**
 3:  * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
 4:  * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
 5:  *
 6:  * Licensed under The MIT License
 7:  * For full copyright and license information, please see the LICENSE.txt
 8:  * Redistributions of files must retain the above copyright notice.
 9:  *
10:  * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
11:  * @link          https://cakephp.org CakePHP(tm) Project
12:  * @since         3.0.0
13:  * @license       https://opensource.org/licenses/mit-license.php MIT License
14:  */
15: namespace Cake\Collection\Iterator;
16: 
17: use Cake\Collection\Collection;
18: use RecursiveIterator;
19: use Traversable;
20: 
21: /**
22:  * A type of collection that is aware of nested items and exposes methods to
23:  * check or retrieve them
24:  */
25: class NestIterator extends Collection implements RecursiveIterator
26: {
27: 
28:     /**
29:      * The name of the property that contains the nested items for each element
30:      *
31:      * @var string|callable
32:      */
33:     protected $_nestKey;
34: 
35:     /**
36:      * Constructor
37:      *
38:      * @param array|\Traversable $items Collection items.
39:      * @param string|callable $nestKey the property that contains the nested items
40:      * If a callable is passed, it should return the childrens for the passed item
41:      */
42:     public function __construct($items, $nestKey)
43:     {
44:         parent::__construct($items);
45:         $this->_nestKey = $nestKey;
46:     }
47: 
48:     /**
49:      * Returns a traversable containing the children for the current item
50:      *
51:      * @return \Traversable
52:      */
53:     public function getChildren()
54:     {
55:         $property = $this->_propertyExtractor($this->_nestKey);
56: 
57:         return new static($property($this->current()), $this->_nestKey);
58:     }
59: 
60:     /**
61:      * Returns true if there is an array or a traversable object stored under the
62:      * configured nestKey for the current item
63:      *
64:      * @return bool
65:      */
66:     public function hasChildren()
67:     {
68:         $property = $this->_propertyExtractor($this->_nestKey);
69:         $children = $property($this->current());
70: 
71:         if (is_array($children)) {
72:             return !empty($children);
73:         }
74: 
75:         return $children instanceof Traversable;
76:     }
77: }
78: