Chris@0: <?php
Chris@0: 
Chris@0: /*
Chris@0:  * This file is part of the Symfony package.
Chris@0:  *
Chris@0:  * (c) Fabien Potencier <fabien@symfony.com>
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 Symfony\Component\DependencyInjection\Compiler;
Chris@0: 
Chris@0: use Symfony\Component\DependencyInjection\Exception\ServiceCircularReferenceException;
Chris@0: use Symfony\Component\DependencyInjection\ContainerBuilder;
Chris@0: 
Chris@0: /**
Chris@0:  * Checks your services for circular references.
Chris@0:  *
Chris@0:  * References from method calls are ignored since we might be able to resolve
Chris@0:  * these references depending on the order in which services are called.
Chris@0:  *
Chris@0:  * Circular reference from method calls will only be detected at run-time.
Chris@0:  *
Chris@0:  * @author Johannes M. Schmitt <schmittjoh@gmail.com>
Chris@0:  */
Chris@0: class CheckCircularReferencesPass implements CompilerPassInterface
Chris@0: {
Chris@0:     private $currentPath;
Chris@0:     private $checkedNodes;
Chris@0: 
Chris@0:     /**
Chris@0:      * Checks the ContainerBuilder object for circular references.
Chris@0:      *
Chris@0:      * @param ContainerBuilder $container The ContainerBuilder instances
Chris@0:      */
Chris@0:     public function process(ContainerBuilder $container)
Chris@0:     {
Chris@0:         $graph = $container->getCompiler()->getServiceReferenceGraph();
Chris@0: 
Chris@0:         $this->checkedNodes = array();
Chris@0:         foreach ($graph->getNodes() as $id => $node) {
Chris@0:             $this->currentPath = array($id);
Chris@0: 
Chris@0:             $this->checkOutEdges($node->getOutEdges());
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Checks for circular references.
Chris@0:      *
Chris@0:      * @param ServiceReferenceGraphEdge[] $edges An array of Edges
Chris@0:      *
Chris@0:      * @throws ServiceCircularReferenceException When a circular reference is found.
Chris@0:      */
Chris@0:     private function checkOutEdges(array $edges)
Chris@0:     {
Chris@0:         foreach ($edges as $edge) {
Chris@0:             $node = $edge->getDestNode();
Chris@0:             $id = $node->getId();
Chris@0: 
Chris@0:             if (empty($this->checkedNodes[$id])) {
Chris@0:                 // don't check circular dependencies for lazy services
Chris@0:                 if (!$node->getValue() || !$node->getValue()->isLazy()) {
Chris@0:                     $searchKey = array_search($id, $this->currentPath);
Chris@0:                     $this->currentPath[] = $id;
Chris@0: 
Chris@0:                     if (false !== $searchKey) {
Chris@0:                         throw new ServiceCircularReferenceException($id, array_slice($this->currentPath, $searchKey));
Chris@0:                     }
Chris@0: 
Chris@0:                     $this->checkOutEdges($node->getOutEdges());
Chris@0:                 }
Chris@0: 
Chris@0:                 $this->checkedNodes[$id] = true;
Chris@0:                 array_pop($this->currentPath);
Chris@0:             }
Chris@0:         }
Chris@0:     }
Chris@0: }