--- /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\Definition;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\DependencyInjection\Reference;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Exception\RuntimeException;
+use Symfony\Component\DependencyInjection\Exception\ScopeCrossingInjectionException;
+use Symfony\Component\DependencyInjection\Exception\ScopeWideningInjectionException;
+
+/**
+ * Checks the validity of references.
+ *
+ * The following checks are performed by this pass:
+ * - target definitions are not abstract
+ * - target definitions are of equal or wider scope
+ * - target definitions are in the same scope hierarchy
+ *
+ * @author Johannes M. Schmitt <schmittjoh@gmail.com>
+ */
+class CheckReferenceValidityPass implements CompilerPassInterface
+{
+ private $container;
+ private $currentId;
+ private $currentScope;
+ private $currentScopeAncestors;
+ private $currentScopeChildren;
+
+ /**
+ * Processes the ContainerBuilder to validate References.
+ *
+ * @param ContainerBuilder $container
+ */
+ public function process(ContainerBuilder $container)
+ {
+ $this->container = $container;
+
+ $children = $this->container->getScopeChildren(false);
+ $ancestors = array();
+
+ $scopes = $this->container->getScopes(false);
+ foreach ($scopes as $name => $parent) {
+ $ancestors[$name] = array($parent);
+
+ while (isset($scopes[$parent])) {
+ $ancestors[$name][] = $parent = $scopes[$parent];
+ }
+ }
+
+ foreach ($container->getDefinitions() as $id => $definition) {
+ if ($definition->isSynthetic() || $definition->isAbstract()) {
+ continue;
+ }
+
+ $this->currentId = $id;
+ $this->currentScope = $scope = $definition->getScope(false);
+
+ if (ContainerInterface::SCOPE_CONTAINER === $scope) {
+ $this->currentScopeChildren = array_keys($scopes);
+ $this->currentScopeAncestors = array();
+ } elseif (ContainerInterface::SCOPE_PROTOTYPE !== $scope) {
+ $this->currentScopeChildren = isset($children[$scope]) ? $children[$scope] : array();
+ $this->currentScopeAncestors = isset($ancestors[$scope]) ? $ancestors[$scope] : array();
+ }
+
+ $this->validateReferences($definition->getArguments());
+ $this->validateReferences($definition->getMethodCalls());
+ $this->validateReferences($definition->getProperties());
+ }
+ }
+
+ /**
+ * Validates an array of References.
+ *
+ * @param array $arguments An array of Reference objects
+ *
+ * @throws RuntimeException when there is a reference to an abstract definition.
+ */
+ private function validateReferences(array $arguments)
+ {
+ foreach ($arguments as $argument) {
+ if (is_array($argument)) {
+ $this->validateReferences($argument);
+ } elseif ($argument instanceof Reference) {
+ $targetDefinition = $this->getDefinition((string) $argument);
+
+ if (null !== $targetDefinition && $targetDefinition->isAbstract()) {
+ throw new RuntimeException(sprintf(
+ 'The definition "%s" has a reference to an abstract definition "%s". '
+ .'Abstract definitions cannot be the target of references.',
+ $this->currentId,
+ $argument
+ ));
+ }
+
+ $this->validateScope($argument, $targetDefinition);
+ }
+ }
+ }
+
+ /**
+ * Validates the scope of a single Reference.
+ *
+ * @param Reference $reference
+ * @param Definition $definition
+ *
+ * @throws ScopeWideningInjectionException when the definition references a service of a narrower scope
+ * @throws ScopeCrossingInjectionException when the definition references a service of another scope hierarchy
+ */
+ private function validateScope(Reference $reference, Definition $definition = null)
+ {
+ if (ContainerInterface::SCOPE_PROTOTYPE === $this->currentScope) {
+ return;
+ }
+
+ if (!$reference->isStrict(false)) {
+ return;
+ }
+
+ if (null === $definition) {
+ return;
+ }
+
+ if ($this->currentScope === $scope = $definition->getScope(false)) {
+ return;
+ }
+
+ $id = (string) $reference;
+
+ if (in_array($scope, $this->currentScopeChildren, true)) {
+ throw new ScopeWideningInjectionException($this->currentId, $this->currentScope, $id, $scope);
+ }
+
+ if (!in_array($scope, $this->currentScopeAncestors, true)) {
+ throw new ScopeCrossingInjectionException($this->currentId, $this->currentScope, $id, $scope);
+ }
+ }
+
+ /**
+ * Returns the Definition given an id.
+ *
+ * @param string $id Definition identifier
+ *
+ * @return Definition
+ */
+ private function getDefinition($id)
+ {
+ if (!$this->container->hasDefinition($id)) {
+ return;
+ }
+
+ return $this->container->getDefinition($id);
+ }
+}