--- /dev/null
+<?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\ContainerInterface;
+use Symfony\Component\DependencyInjection\Reference;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Exception\RuntimeException;
+
+/**
+ * Emulates the invalid behavior if the reference is not found within the
+ * container.
+ *
+ * @author Johannes M. Schmitt <schmittjoh@gmail.com>
+ */
+class ResolveInvalidReferencesPass implements CompilerPassInterface
+{
+ private $container;
+
+ /**
+ * Process the ContainerBuilder to resolve invalid references.
+ *
+ * @param ContainerBuilder $container
+ */
+ public function process(ContainerBuilder $container)
+ {
+ $this->container = $container;
+ foreach ($container->getDefinitions() as $definition) {
+ if ($definition->isSynthetic() || $definition->isAbstract()) {
+ continue;
+ }
+
+ $definition->setArguments(
+ $this->processArguments($definition->getArguments())
+ );
+
+ $calls = array();
+ foreach ($definition->getMethodCalls() as $call) {
+ try {
+ $calls[] = array($call[0], $this->processArguments($call[1], true));
+ } catch (RuntimeException $e) {
+ // this call is simply removed
+ }
+ }
+ $definition->setMethodCalls($calls);
+
+ $properties = array();
+ foreach ($definition->getProperties() as $name => $value) {
+ try {
+ $value = $this->processArguments(array($value), true);
+ $properties[$name] = reset($value);
+ } catch (RuntimeException $e) {
+ // ignore property
+ }
+ }
+ $definition->setProperties($properties);
+ }
+ }
+
+ /**
+ * Processes arguments to determine invalid references.
+ *
+ * @param array $arguments An array of Reference objects
+ * @param bool $inMethodCall
+ *
+ * @return array
+ *
+ * @throws RuntimeException When the config is invalid
+ */
+ private function processArguments(array $arguments, $inMethodCall = false)
+ {
+ foreach ($arguments as $k => $argument) {
+ if (is_array($argument)) {
+ $arguments[$k] = $this->processArguments($argument, $inMethodCall);
+ } elseif ($argument instanceof Reference) {
+ $id = (string) $argument;
+
+ $invalidBehavior = $argument->getInvalidBehavior();
+ $exists = $this->container->has($id);
+
+ // resolve invalid behavior
+ if (!$exists && ContainerInterface::NULL_ON_INVALID_REFERENCE === $invalidBehavior) {
+ $arguments[$k] = null;
+ } elseif (!$exists && ContainerInterface::IGNORE_ON_INVALID_REFERENCE === $invalidBehavior) {
+ if ($inMethodCall) {
+ throw new RuntimeException('Method shouldn\'t be called.');
+ }
+
+ $arguments[$k] = null;
+ }
+ }
+ }
+
+ return $arguments;
+ }
+}