Allow service container loader to be overridden

Author: pamil

src/ServiceContainer/ServiceContainerExtension.php

@@ -16,6 +16,7 @@
 use Symfony\Component\Config\Definition\Builder\ArrayNodeDefinition;
 use Symfony\Component\Config\FileLocator;
 use Symfony\Component\Config\Loader\DelegatingLoader;
+use Symfony\Component\Config\Loader\LoaderInterface;
 use Symfony\Component\Config\Loader\LoaderResolver;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Loader\PhpFileLoader;
@@ -28,6 +29,36 @@
 final class ServiceContainerExtension implements Extension
 {
     /**
+     * @var callable<ContainerBuilder, array>:LoaderInterface
+     */
+    private $loaderCallable;
+
+    public function __construct()
+    {
+        $this->loaderCallable = function (ContainerBuilder $container, array $config) {
+            $fileLocator = new FileLocator($container->getParameter('paths.base'));
+
+            return new DelegatingLoader(new LoaderResolver([
+                new XmlFileLoader($container, $fileLocator),
+                new YamlFileLoader($container, $fileLocator),
+                new PhpFileLoader($container, $fileLocator),
+            ]));
+        };
+    }
+
+    /**
+     * @api
+     *
+     * @param callable<ContainerBuilder, array>:LoaderInterface $loaderCallable
+     */
+    public function setLoaderCallable(callable $loaderCallable)
+    {
+        $this->loaderCallable = $loaderCallable;
+    }
+
+    /**
+     * @internal
+     *
      * {@inheritdoc}
      */
     public function getConfigKey()
@@ -36,6 +67,8 @@ public function getConfigKey()
     }
 
     /**
+     * @internal
+     *
      * {@inheritdoc}
      */
     public function initialize(ExtensionManager $extensionManager)
@@ -44,6 +77,8 @@ public function initialize(ExtensionManager $extensionManager)
     }
 
     /**
+     * @internal
+     *
      * {@inheritdoc}
      */
     public function configure(ArrayNodeDefinition $builder)
@@ -57,24 +92,25 @@ public function configure(ArrayNodeDefinition $builder)
     }
 
     /**
+     * @internal
+     *
      * {@inheritdoc}
      */
     public function load(ContainerBuilder $container, array $config)
     {
-        $fileLocator = new FileLocator($container->getParameter('paths.base'));
+        $loaderCallable = $this->loaderCallable;
 
-        $loader = new DelegatingLoader(new LoaderResolver([
-            new XmlFileLoader($container, $fileLocator),
-            new YamlFileLoader($container, $fileLocator),
-            new PhpFileLoader($container, $fileLocator),
-        ]));
+        /** @var LoaderInterface $loader */
+        $loader = $loaderCallable($container, $config);
 
         foreach ($config['imports'] as $file) {
             $loader->load($file);
         }
     }
 
     /**
+     * @internal
+     *
      * {@inheritdoc}
      */
     public function process(ContainerBuilder $container)