Chris@0: <?php
Chris@0: /*
Chris@0:  * This file is part of the Comparator package.
Chris@0:  *
Chris@0:  * (c) Sebastian Bergmann <sebastian@phpunit.de>
Chris@0:  *
Chris@0:  * For the full copyright and license information, please view the LICENSE
Chris@0:  * file that was distributed with this source code.
Chris@0:  */
Chris@0: 
Chris@0: namespace SebastianBergmann\Comparator;
Chris@0: 
Chris@0: /**
Chris@0:  * Factory for comparators which compare values for equality.
Chris@0:  */
Chris@0: class Factory
Chris@0: {
Chris@0:     /**
Chris@0:      * @var Comparator[]
Chris@0:      */
Chris@0:     private $comparators = array();
Chris@0: 
Chris@0:     /**
Chris@0:      * @var Factory
Chris@0:      */
Chris@0:     private static $instance;
Chris@0: 
Chris@0:     /**
Chris@0:      * Constructs a new factory.
Chris@0:      */
Chris@0:     public function __construct()
Chris@0:     {
Chris@0:         $this->register(new TypeComparator);
Chris@0:         $this->register(new ScalarComparator);
Chris@0:         $this->register(new NumericComparator);
Chris@0:         $this->register(new DoubleComparator);
Chris@0:         $this->register(new ArrayComparator);
Chris@0:         $this->register(new ResourceComparator);
Chris@0:         $this->register(new ObjectComparator);
Chris@0:         $this->register(new ExceptionComparator);
Chris@0:         $this->register(new SplObjectStorageComparator);
Chris@0:         $this->register(new DOMNodeComparator);
Chris@0:         $this->register(new MockObjectComparator);
Chris@0:         $this->register(new DateTimeComparator);
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * @return Factory
Chris@0:      */
Chris@0:     public static function getInstance()
Chris@0:     {
Chris@0:         if (self::$instance === null) {
Chris@0:             self::$instance = new self;
Chris@0:         }
Chris@0: 
Chris@0:         return self::$instance;
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Returns the correct comparator for comparing two values.
Chris@0:      *
Chris@0:      * @param  mixed      $expected The first value to compare
Chris@0:      * @param  mixed      $actual   The second value to compare
Chris@0:      * @return Comparator
Chris@0:      */
Chris@0:     public function getComparatorFor($expected, $actual)
Chris@0:     {
Chris@0:         foreach ($this->comparators as $comparator) {
Chris@0:             if ($comparator->accepts($expected, $actual)) {
Chris@0:                 return $comparator;
Chris@0:             }
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Registers a new comparator.
Chris@0:      *
Chris@0:      * This comparator will be returned by getInstance() if its accept() method
Chris@0:      * returns TRUE for the compared values. It has higher priority than the
Chris@0:      * existing comparators, meaning that its accept() method will be tested
Chris@0:      * before those of the other comparators.
Chris@0:      *
Chris@0:      * @param Comparator $comparator The registered comparator
Chris@0:      */
Chris@0:     public function register(Comparator $comparator)
Chris@0:     {
Chris@0:         array_unshift($this->comparators, $comparator);
Chris@0: 
Chris@0:         $comparator->setFactory($this);
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Unregisters a comparator.
Chris@0:      *
Chris@0:      * This comparator will no longer be returned by getInstance().
Chris@0:      *
Chris@0:      * @param Comparator $comparator The unregistered comparator
Chris@0:      */
Chris@0:     public function unregister(Comparator $comparator)
Chris@0:     {
Chris@0:         foreach ($this->comparators as $key => $_comparator) {
Chris@0:             if ($comparator === $_comparator) {
Chris@0:                 unset($this->comparators[$key]);
Chris@0:             }
Chris@0:         }
Chris@0:     }
Chris@0: }