<?php /* * This file is part of the Symfony package. * * (c) Fabien Potencier <fabien@symfony.com> * * For the full copyright and license information, please view the LICENSE * file that was distributed with this source code. */ namespace Symfony\Component\DependencyInjection\Compiler; use Symfony\Component\DependencyInjection\Exception\ServiceCircularReferenceException; use Symfony\Component\DependencyInjection\ContainerBuilder; /** * Checks your services for circular references * * References from method calls are ignored since we might be able to resolve * these references depending on the order in which services are called. * * Circular reference from method calls will only be detected at run-time. * * @author Johannes M. Schmitt <schmittjoh@gmail.com> */ class CheckCircularReferencesPass implements CompilerPassInterface { private $currentId; private $currentPath; private $checkedNodes; /** * Checks the ContainerBuilder object for circular references. * * @param ContainerBuilder $container The ContainerBuilder instances */ public function process(ContainerBuilder $container) { $graph = $container->getCompiler()->getServiceReferenceGraph(); $this->checkedNodes = array(); foreach ($graph->getNodes() as $id => $node) { $this->currentId = $id; $this->currentPath = array($id); $this->checkOutEdges($node->getOutEdges()); } } /** * Checks for circular references. * * @param ServiceReferenceGraphEdge[] $edges An array of Edges * * @throws ServiceCircularReferenceException When a circular reference is found. */ private function checkOutEdges(array $edges) { foreach ($edges as $edge) { $node = $edge->getDestNode(); $id = $node->getId(); if (empty($this->checkedNodes[$id])) { $searchKey = array_search($id, $this->currentPath); $this->currentPath[] = $id; if (false !== $searchKey) { throw new ServiceCircularReferenceException($id, array_slice($this->currentPath, $searchKey)); } $this->checkOutEdges($node->getOutEdges()); $this->checkedNodes[$id] = true; array_pop($this->currentPath); } } } }