add loader that processes configuration as symfony does

spec/Tacker/Loader/ProcessorLoaderSpec.php

@@ -0,0 +1,51 @@
+<?php
+
+namespace spec\Tacker\Loader;
+
+use Symfony\Component\Config\Definition\Builder\TreeBuilder;
+
+class ProcessorLoaderSpec extends \PhpSpec\ObjectBehavior
+{
+    /**
+     * @param Symfony\Component\Config\Loader\LoaderInterface $loader
+     * @param Symfony\Component\Config\Definition\ConfigurationInterface $configuration
+     */
+    function let($loader, $configuration)
+    {
+        $this->beConstructedWith($loader, $configuration);
+    }
+
+    function it_is_initializable()
+    {
+        $this->shouldHaveType('Tacker\Loader\ProcessorLoader');
+    }
+
+    function it_processes_configuration($loader, $configuration)
+    {
+        $builder = new TreeBuilder;
+        $root = $builder->root('');
+        $root
+            ->children()
+                ->booleanNode('auto_connect')
+                    ->defaultTrue()
+                ->end()
+            ->end()
+        ;
+
+
+        $configuration->getConfigTreeBuilder()->willReturn($builder);
+
+        $loader->load('file', null)->willReturn([]);
+
+        $this->load('file')->shouldReturn(['auto_connect' => true]);
+    }
+
+    function it_delegates_supports_to_loader($loader)
+    {
+        $loader->supports('php', null)->willReturn(false)->shouldBeCalled();
+        $loader->supports('yml', null)->willReturn(true)->shouldBeCalled();
+
+        $this->supports('php')->shouldReturn(false);
+        $this->supports('yml')->shouldReturn(true);
+    }
+}

src/Loader/ProcessorLoader.php

@@ -0,0 +1,38 @@
+<?php
+
+namespace Tacker\Loader;
+
+use Symfony\Component\Config\Definition\ConfigurationInterface;
+use Symfony\Component\Config\Definition\Processor;
+use Symfony\Component\Config\Loader\LoaderInterface;
+
+class ProcessorLoader extends \Symfony\Component\Config\Loader\Loader
+{
+    private $loader;
+    private $configuration;
+
+    public function __construct(LoaderInterface $loader, ConfigurationInterface $configuration)
+    {
+        $this->loader = $loader;
+        $this->configuration = $configuration;
+    }
+
+    public function load($resource, $type = null)
+    {
+        $parameters = $this->loader->load($resource, $type);
+
+        return $this->processConfiguration($parameters);
+    }
+
+    public function supports($resource, $type = null)
+    {
+        return $this->loader->supports($resource, $type);
+    }
+
+    private function processConfiguration(array $parameters)
+    {
+        $processor = new Processor;
+
+        return $processor->processConfiguration($this->configuration, [$parameters]);
+    }
+}

src/LoaderBuilder.php

@@ -3,12 +3,14 @@
 namespace Tacker;
 
 use Symfony\Component\Config\FileLocator;
+use Symfony\Component\Config\Definition\ConfigurationInterface;
 use Symfony\Component\Config\Loader\LoaderResolver;
 use Symfony\Component\Config\Loader\DelegatingLoader;
 use Tacker\Loader\CacheLoader;
 use Tacker\Loader\IniFileLoader;
 use Tacker\Loader\JsonFileLoader;
 use Tacker\Loader\NormalizerLoader;
+use Tacker\Loader\ProcessorLoader;
 use Tacker\Loader\PhpFileLoader;
 use Tacker\Loader\YamlFileLoader;
 use Tacker\Normalizer\ChainNormalizer;
@@ -26,6 +28,7 @@ final class LoaderBuilder
     private $normalizer;
     private $resolver;
     private $resources;
+    private $configuration;
     private $locator;
     private $debug;
     private $cacheDir;
@@ -79,6 +82,11 @@ public function setDebug($debug)
         return $this;
     }
 
+    public function setConfiguration(ConfigurationInterface $configuration)
+    {
+        $this->configuration = $configuration;
+    }
+
     public function build()
     {
         if (false == $this->resolverConfigured) {
@@ -89,7 +97,13 @@ public function build()
             $this->addDefaultNormalizers();
         }
 
-        $loader = new CacheLoader($this->createNormalizerLoader(), $this->resources);
+        $loader = $this->createNormalizerLoader();
+
+        if ($this->configuration) {
+            $loader = new ProcessorLoader($loader, $this->configuration);
+        }
+
+        $loader = new CacheLoader($loader, $this->resources);
         $loader->setCacheDir($this->cacheDir);
         $loader->setDebug($this->debug);