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;
 16: 
 17: use ArrayIterator;
 18: use InvalidArgumentException;
 19: use IteratorIterator;
 20: use Serializable;
 21: use Traversable;
 22: 
 23: /**
 24:  * A collection is an immutable list of elements with a handful of functions to
 25:  * iterate, group, transform and extract information from it.
 26:  */
 27: class Collection extends IteratorIterator implements CollectionInterface, Serializable
 28: {
 29:     use CollectionTrait;
 30: 
 31:     /**
 32:      * Constructor. You can provide an array or any traversable object
 33:      *
 34:      * @param array|\Traversable $items Items.
 35:      * @throws \InvalidArgumentException If passed incorrect type for items.
 36:      */
 37:     public function __construct($items)
 38:     {
 39:         if (is_array($items)) {
 40:             $items = new ArrayIterator($items);
 41:         }
 42: 
 43:         if (!($items instanceof Traversable)) {
 44:             $msg = 'Only an array or \Traversable is allowed for Collection';
 45:             throw new InvalidArgumentException($msg);
 46:         }
 47: 
 48:         parent::__construct($items);
 49:     }
 50: 
 51:     /**
 52:      * Returns a string representation of this object that can be used
 53:      * to reconstruct it
 54:      *
 55:      * @return string
 56:      */
 57:     public function serialize()
 58:     {
 59:         return serialize($this->buffered());
 60:     }
 61: 
 62:     /**
 63:      * Unserializes the passed string and rebuilds the Collection instance
 64:      *
 65:      * @param string $collection The serialized collection
 66:      * @return void
 67:      */
 68:     public function unserialize($collection)
 69:     {
 70:         $this->__construct(unserialize($collection));
 71:     }
 72: 
 73:     /**
 74:      * {@inheritDoc}
 75:      *
 76:      * @return int
 77:      */
 78:     public function count()
 79:     {
 80:         $traversable = $this->optimizeUnwrap();
 81: 
 82:         if (is_array($traversable)) {
 83:             return count($traversable);
 84:         }
 85: 
 86:         return iterator_count($traversable);
 87:     }
 88: 
 89:     /**
 90:      * {@inheritDoc}
 91:      *
 92:      * @return int
 93:      */
 94:     public function countKeys()
 95:     {
 96:         return count($this->toArray());
 97:     }
 98: 
 99:     /**
100:      * Returns an array that can be used to describe the internal state of this
101:      * object.
102:      *
103:      * @return array
104:      */
105:     public function __debugInfo()
106:     {
107:         return [
108:             'count' => $this->count(),
109:         ];
110:     }
111: }
112: