[Routing] refactored loaders

* refactored the import mechanism for better flexibility
 * added two methods to LoaderInterface: supports() and setResolver()
 * added a LoaderResolver interface
 * added a Loader base class
 * added new loaders: DelegatingLoader, ClosureLoader, and PhpFileLoader
 * changed the Router constructor signature (now takes a Loader)

src/Symfony/Components/Routing/Loader/ClosureLoader.php

@@ -0,0 +1,48 @@
+<?php
+
+namespace Symfony\Components\Routing\Loader;
+
+use Symfony\Components\Routing\Resource\FileResource;
+
+/*
+ * This file is part of the Symfony framework.
+ *
+ * The Closure must return a RouteCollection instance.
+ *
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+/**
+ * ClosureLoader loads routes from a PHP closure.
+ *
+ * @package    Symfony
+ * @subpackage Components_Routing
+ * @author     Fabien Potencier <fabien.potencier@symfony-project.com>
+ */
+class ClosureLoader extends Loader
+{
+    /**
+     * Loads a Closure.
+     *
+     * @param \Closure $resource The resource
+     */
+    public function load($closure)
+    {
+        return call_user_func($closure);
+    }
+
+    /**
+     * Returns true if this class supports the given resource.
+     *
+     * @param  mixed $resource A resource
+     *
+     * @return Boolean true if this class supports the given resource, false otherwise
+     */
+    public function supports($resource)
+    {
+        return $resource instanceof \Closure;
+    }
+}

src/Symfony/Components/Routing/Loader/DelegatingLoader.php

@@ -0,0 +1,70 @@
+<?php
+
+namespace Symfony\Components\Routing\Loader;
+
+/*
+ * This file is part of the Symfony framework.
+ *
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+/**
+ * DelegatingLoader delegates route loading to other loaders using a loader resolver.
+ *
+ * @package    Symfony
+ * @subpackage Components_Routing
+ * @author     Fabien Potencier <fabien.potencier@symfony-project.com>
+ */
+class DelegatingLoader extends Loader
+{
+    protected $resolver;
+
+    /**
+     * Constructor.
+     *
+     * @param \Symfony\Components\Routing\Loader\LoaderResolverInterface $resolver A LoaderResolverInterface instance
+     */
+    public function __construct(LoaderResolverInterface $resolver)
+    {
+        $this->resolver = $resolver;
+    }
+
+    /**
+     * Loads a resource.
+     *
+     * @param  mixed $resource A resource
+     *
+     * @return \Symfony\Components\Routing\RouteCollection A RouteCollection instance
+     */
+    public function load($resource)
+    {
+        $loader = $this->resolver->resolve($resource);
+
+        if (false === $loader) {
+            throw new \InvalidArgumentException(sprintf('Unable to load the "%s" routing resource.', is_string($resource) ? $resource : (is_object($resource) ? get_class($resource) : 'RESOURCE')));
+        }
+
+        return $loader->load($resource);
+    }
+
+    /**
+     * Returns true if this class supports the given resource.
+     *
+     * @param  mixed $resource A resource
+     *
+     * @return Boolean true if this class supports the given resource, false otherwise
+     */
+    public function supports($resource)
+    {
+        foreach ($this->resolver->getLoaders() as $loader) {
+            if ($loader->supports($resource)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}

src/Symfony/Components/Routing/Loader/FileLoader.php

@@ -18,8 +18,9 @@ namespace Symfony\Components\Routing\Loader;
  * @subpackage Components_Routing
  * @author     Fabien Potencier <fabien.potencier@symfony-project.com>
  */
-abstract class FileLoader implements LoaderInterface
+abstract class FileLoader extends Loader
 {
+    protected $currentDir;
     protected $paths;
 
     /**
@@ -32,10 +33,27 @@ abstract class FileLoader implements LoaderInterface
         if (!is_array($paths)) {
             $paths = array($paths);
         }
-
         $this->paths = $paths;
     }
 
+    /**
+     * Adds routes from a resource.
+     *
+     * @param mixed  $resource   A Resource
+     *
+     * @return Symfony\Components\Routing\RouteCollection A RouteCollection instance
+     */
+    public function import($resource)
+    {
+        $loader = $this->resolve($resource);
+
+        if ($loader instanceof FileLoader && null !== $this->currentDir) {
+            $resource = $this->getAbsolutePath($resource, $this->currentDir);
+        }
+
+        return $loader->load($resource);
+    }
+
     /**
      * @throws \InvalidArgumentException When file is not found
      */

src/Symfony/Components/Routing/Loader/Loader.php

@@ -0,0 +1,79 @@
+<?php
+
+namespace Symfony\Components\Routing\Loader;
+
+/*
+ * This file is part of the Symfony framework.
+ *
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+/**
+ * Loader is the abstract class used by all built-in loaders.
+ *
+ * @package    Symfony
+ * @subpackage Components_Routing
+ * @author     Fabien Potencier <fabien.potencier@symfony-project.com>
+ */
+abstract class Loader implements LoaderInterface
+{
+    protected $resolver;
+
+    /**
+     * Gets the loader resolver.
+     *
+     * @return \Symfony\Components\Routing\Loader\LoaderResolver A LoaderResolver instance
+     */
+    public function getResolver()
+    {
+        return $this->resolver;
+    }
+
+    /**
+     * Sets the loader resolver.
+     *
+     * @param \Symfony\Components\Routing\Loader\LoaderResolver $resolver A LoaderResolver instance
+     */
+    public function setResolver(LoaderResolver $resolver)
+    {
+        $this->resolver = $resolver;
+    }
+
+    /**
+     * Adds definitions and parameters from a resource.
+     *
+     * @param mixed $resource A Resource
+     */
+    public function import($resource)
+    {
+        $this->resolve($resource)->load($resource);
+    }
+
+    /**
+     * Finds a loader able to load an imported resource
+     *
+     * @param mixed $resource A Resource
+     *
+     * @return Symfony\Components\Routing\Loader\LoaderInterface A LoaderInterface instance
+     *
+     * @throws \InvalidArgumentException if no loader is found
+     */
+    public function resolve($resource)
+    {
+        $loader = false;
+        if ($this->supports($resource)) {
+            $loader = $this;
+        } elseif (null !== $this->resolver) {
+            $loader = $this->resolver->resolve($resource);
+        }
+
+        if (false === $loader) {
+            throw new \InvalidArgumentException(sprintf('Unable to load the "%s" routing resource.', is_string($resource) ? $resource : (is_object($resource) ? get_class($resource) : 'RESOURCE')));
+        }
+
+        return $loader;
+    }
+}

src/Symfony/Components/Routing/Loader/LoaderInterface.php

@@ -2,6 +2,8 @@
 
 namespace Symfony\Components\Routing\Loader;
 
+use Symfony\Components\Routing\Loader\LoaderResolver;
+
 /*
  * This file is part of the Symfony framework.
  *
@@ -28,4 +30,27 @@ interface LoaderInterface
      * @return RouteCollection A RouteCollection instance
      */
     function load($resource);
+
+    /**
+     * Returns true if this class supports the given resource.
+     *
+     * @param  mixed $resource A resource
+     *
+     * @return Boolean true if this class supports the given resource, false otherwise
+     */
+    function supports($resource);
+
+    /**
+     * Gets the loader resolver.
+     *
+     * @return \Symfony\Components\Routing\Loader\LoaderResolver A LoaderResolver instance
+     */
+    function getResolver();
+
+    /**
+     * Sets the loader resolver.
+     *
+     * @param \Symfony\Components\Routing\Loader\LoaderResolver $resolver A LoaderResolver instance
+     */
+    function setResolver(LoaderResolver $resolver);
 }

src/Symfony/Components/Routing/Loader/LoaderResolver.php

@@ -0,0 +1,76 @@
+<?php
+
+namespace Symfony\Components\Routing\Loader;
+
+/*
+ * This file is part of the Symfony framework.
+ *
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+/**
+ * LoaderResolver selects a loader for a given resource..
+ *
+ * @package    Symfony
+ * @subpackage Components_Routing
+ * @author     Fabien Potencier <fabien.potencier@symfony-project.com>
+ */
+class LoaderResolver implements LoaderResolverInterface
+{
+    protected $loaders;
+
+    /**
+     * Constructor.
+     *
+     * @param \Symfony\Components\Routing\Loader\LoaderInterface[] $loaders An array of loaders
+     */
+    public function __construct(array $loaders = array())
+    {
+        $this->loaders = array();
+        foreach ($loaders as $loader) {
+            $this->addLoader($loader);
+        }
+    }
+
+    /**
+     * Returns a loader able to load the resource.
+     *
+     * @param mixed  $resource A resource
+     *
+     * @return Symfony\Components\Routing\Loader\LoaderInterface A LoaderInterface instance
+     */
+    public function resolve($resource)
+    {
+        foreach ($this->loaders as $loader) {
+            if ($loader->supports($resource)) {
+                return $loader;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Sets a loader.
+     *
+     * @param \Symfony\Components\Routing\Loader\LoaderInterface $loader A LoaderInterface instance
+     */
+    public function addLoader(LoaderInterface $loader)
+    {
+        $this->loaders[] = $loader;
+        $loader->setResolver($this);
+    }
+
+    /**
+     * Returns the registered loaders.
+     *
+     * @return \Symfony\Components\Routing\Loader\LoaderInterface[] A array of LoaderInterface instances
+     */
+    public function getLoaders()
+    {
+        return $this->loaders;
+    }
+}

src/Symfony/Components/Routing/Loader/LoaderResolverInterface.php

@@ -0,0 +1,31 @@
+<?php
+
+namespace Symfony\Components\Routing\Loader;
+
+/*
+ * This file is part of the Symfony framework.
+ *
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+/**
+ * LoaderResolverInterface selects a loader for a given resource.
+ *
+ * @package    Symfony
+ * @subpackage Components_Routing
+ * @author     Fabien Potencier <fabien.potencier@symfony-project.com>
+ */
+interface LoaderResolverInterface
+{
+    /**
+     * Returns a loader able to load the resource.
+     *
+     * @param mixed  $resource A resource
+     *
+     * @return Symfony\Components\Routing\Loader\LoaderInterface A LoaderInterface instance
+     */
+    function resolve($resource);
+}

src/Symfony/Components/Routing/Loader/PhpFileLoader.php

@@ -0,0 +1,56 @@
+<?php
+
+namespace Symfony\Components\Routing\Loader;
+
+use Symfony\Components\Routing\Resource\FileResource;
+
+/*
+ * This file is part of the Symfony framework.
+ *
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+/**
+ * PhpFileLoader loads routes from a PHP file.
+ *
+ * The file must return a RouteCollection instance.
+ *
+ * @package    Symfony
+ * @subpackage Components_Routing
+ * @author     Fabien Potencier <fabien.potencier@symfony-project.com>
+ */
+class PhpFileLoader extends FileLoader
+{
+    /**
+     * Loads an array of PHP files.
+     *
+     * @param mixed $resource The resource
+     */
+    public function load($file)
+    {
+        $loader = $this;
+
+        $path = $this->findFile($file);
+
+        $collection = include $path;
+        $this->currentDir = dirname($path);
+        $collection->addResource(new FileResource($path));
+
+        return $collection;
+    }
+
+    /**
+     * Returns true if this class supports the given resource.
+     *
+     * @param  mixed $resource A resource
+     *
+     * @return Boolean true if this class supports the given resource, false otherwise
+     */
+    public function supports($resource)
+    {
+        return is_string($resource) && 'php' === pathinfo($resource, PATHINFO_EXTENSION);
+    }
+}

src/Symfony/Components/Routing/Loader/XmlFileLoader.php

@@ -53,7 +53,10 @@ class XmlFileLoader extends FileLoader
                     $this->parseRoute($collection, $node, $path);
                     break;
                 case 'import':
-                    $this->parseImport($collection, $node, $path);
+                    $resource = (string) $node->getAttribute('resource');
+                    $prefix = (string) $node->getAttribute('prefix');
+                    $this->currentDir = dirname($path);
+                    $collection->addCollection($this->import($resource), $prefix);
                     break;
                 default:
                     throw new \InvalidArgumentException(sprintf('Unable to parse tag "%s"', $node->tagName));
@@ -63,6 +66,18 @@ class XmlFileLoader extends FileLoader
         return $collection;
     }
 
+    /**
+     * Returns true if this class supports the given resource.
+     *
+     * @param  mixed $resource A resource
+     *
+     * @return Boolean true if this class supports the given resource, false otherwise
+     */
+    public function supports($resource)
+    {
+        return is_string($resource) && 'xml' === pathinfo($resource, PATHINFO_EXTENSION);
+    }
+
     protected function parseRoute(RouteCollection $collection, $definition, $file)
     {
         $defaults = array();
@@ -94,27 +109,6 @@ class XmlFileLoader extends FileLoader
         $collection->addRoute((string) $definition->getAttribute('id'), $route);
     }
 
-    protected function parseImport(RouteCollection $collection, $node, $file)
-    {
-        $class = null;
-        if ($node->hasAttribute('class') && $import->getAttribute('class') !== get_class($this)) {
-            $class = (string) $node->getAttribute('class');
-        } else {
-            // try to detect loader with the extension
-            switch (pathinfo((string) $node->getAttribute('resource'), PATHINFO_EXTENSION)) {
-                case 'yml':
-                    $class = 'Symfony\\Components\\Routing\\Loader\\YamlFileLoader';
-                    break;
-            }
-        }
-
-        $loader = null === $class ? $this : new $class($this->paths);
-
-        $importedFile = $this->getAbsolutePath((string) $node->getAttribute('resource'), dirname($file));
-
-        $collection->addCollection($loader->load($importedFile), (string) $node->getAttribute('prefix'));
-    }
-
     /**
      * @throws \InvalidArgumentException When loading of XML file returns error
      */

src/Symfony/Components/Routing/Loader/YamlFileLoader.php

@@ -45,7 +45,9 @@ class YamlFileLoader extends FileLoader
 
         foreach ($config as $name => $config) {
             if (isset($config['resource'])) {
-                $this->parseImport($collection, $name, $config, $path);
+                $prefix = isset($config['prefix']) ? $config['prefix'] : null;
+                $this->currentDir = dirname($path);
+                $collection->addCollection($this->import($config['resource']), $prefix);
             } elseif (isset($config['pattern'])) {
                 $this->parseRoute($collection, $name, $config, $path);
             } else {
@@ -56,6 +58,18 @@ class YamlFileLoader extends FileLoader
         return $collection;
     }
 
+    /**
+     * Returns true if this class supports the given resource.
+     *
+     * @param  mixed $resource A resource
+     *
+     * @return Boolean true if this class supports the given resource, false otherwise
+     */
+    public function supports($resource)
+    {
+        return is_string($resource) && 'yml' === pathinfo($resource, PATHINFO_EXTENSION);
+    }
+
     /**
      * @throws \InvalidArgumentException When config pattern is not defined for the given route
      */
@@ -74,34 +88,6 @@ class YamlFileLoader extends FileLoader
         $collection->addRoute($name, $route);
     }
 
-    /**
-     * @throws \InvalidArgumentException When import resource is not defined
-     */
-    protected function parseImport(RouteCollection $collection, $name, $import, $file)
-    {
-        if (!isset($import['resource'])) {
-            throw new \InvalidArgumentException(sprintf('You must define a "resource" when importing (%s).', $name));
-        }
-
-        $class = null;
-        if (isset($import['class']) && $import['class'] !== get_class($this)) {
-            $class = $import['class'];
-        } else {
-            // try to detect loader with the extension
-            switch (pathinfo($import['resource'], PATHINFO_EXTENSION)) {
-                case 'xml':
-                    $class = 'Symfony\\Components\\Routing\\Loader\\XmlFileLoader';
-                    break;
-            }
-        }
-
-        $loader = null === $class ? $this : new $class($this->paths);
-
-        $importedFile = $this->getAbsolutePath($import['resource'], dirname($file));
-
-        $collection->addCollection($loader->load($importedFile), isset($import['prefix']) ? $import['prefix'] : null);
-    }
-
     protected function loadFile($file)
     {
         return Yaml::load($file);

src/Symfony/Components/Routing/Router.php

@@ -2,6 +2,8 @@
 
 namespace Symfony\Components\Routing;
 
+use Symfony\Components\Routing\Loader\LoaderInterface;
+
 /*
  * This file is part of the Symfony framework.
  *
@@ -28,6 +30,7 @@ class Router implements RouterInterface
     protected $context;
     protected $loader;
     protected $collection;
+    protected $resource;
 
     /**
      * Constructor.
@@ -37,16 +40,18 @@ class Router implements RouterInterface
      *   * cache_dir: The cache directory (or null to disable caching)
      *   * debug:     Whether to enable debugging or not (false by default)
      *
-     * @param mixed $loader   A PHP callable that returns a RouteCollection instance
+     * @param Symfony\Components\Routing\Loader\LoaderInterface $loader A LoaderInterface instance
+     * @param mixed $resource The main resource to load
      * @param array $options  An array of options
      * @param array $context  The context
      * @param array $defaults The default values
      *
      * @throws \InvalidArgumentException When unsupported option is provided
      */
-    public function __construct($loader, array $options = array(), array $context = array(), array $defaults = array())
+    public function __construct(LoaderInterface $loader, $resource, array $options = array(), array $context = array(), array $defaults = array())
     {
         $this->loader = $loader;
+        $this->resource = $resource;
         $this->context = $context;
         $this->defaults = $defaults;
         $this->options = array(
@@ -78,7 +83,7 @@ class Router implements RouterInterface
     public function getRouteCollection()
     {
         if (null === $this->collection) {
-            $this->collection = call_user_func($this->loader);
+            $this->collection = $this->loader->load($this->resource);
         }
 
         return $this->collection;

tests/Symfony/Tests/Components/Routing/Loader/ClosureLoaderTest.php

@@ -0,0 +1,50 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Tests\Components\Routing\Loader;
+
+use Symfony\Components\Routing\Loader\LoaderResolver;
+use Symfony\Components\Routing\Loader\ClosureLoader;
+use Symfony\Components\Routing\Route;
+use Symfony\Components\Routing\RouteCollection;
+
+class ClosureLoaderTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @covers Symfony\Components\Routing\Loader\ClosureLoader::supports
+     */
+    public function testSupports()
+    {
+        $loader = new ClosureLoader();
+
+        $this->assertTrue($loader->supports(function ($container) {}), '->supports() returns true if the resource is loadable');
+        $this->assertFalse($loader->supports('foo.foo'), '->supports() returns true if the resource is loadable');
+    }
+
+    /**
+     * @covers Symfony\Components\Routing\Loader\ClosureLoader::load
+     */
+    public function testLoad()
+    {
+        $loader = new ClosureLoader();
+
+        $route = new Route('/');
+        $routes = $loader->load(function () use ($route)
+        {
+            $routes = new RouteCollection();
+
+            $routes->addRoute('foo', $route);
+
+            return $routes;
+        });
+
+        $this->assertEquals($route, $routes->getRoute('foo'), '->load() loads a \Closure resource');
+    }
+}

tests/Symfony/Tests/Components/Routing/Loader/DelegatingLoaderTest.php

@@ -0,0 +1,88 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Tests\Components\Routing\Loader;
+
+use Symfony\Components\Routing\Loader\LoaderResolver;
+use Symfony\Components\Routing\Loader\DelegatingLoader;
+use Symfony\Components\Routing\Loader\XmlFileLoader;
+use Symfony\Components\Routing\Loader\ClosureLoader;
+use Symfony\Components\Routing\RouteCollection;
+use Symfony\Components\Routing\Route;
+
+class DelegatingLoaderTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @covers Symfony\Components\Routing\Loader\DelegatingLoader::__construct
+     */
+    public function testConstructor()
+    {
+        $resolver = new LoaderResolver();
+        $loader = new DelegatingLoader($resolver);
+        $this->assertTrue(true, '__construct() takes a loader resolver as its first argument');
+    }
+
+    /**
+     * @covers Symfony\Components\Routing\Loader\DelegatingLoader::getResolver
+     * @covers Symfony\Components\Routing\Loader\DelegatingLoader::setResolver
+     */
+    public function testGetSetResolver()
+    {
+        $resolver = new LoaderResolver();
+        $loader = new DelegatingLoader($resolver);
+        $this->assertSame($resolver, $loader->getResolver(), '->getResolver() gets the resolver loader');
+        $loader->setResolver($resolver = new LoaderResolver());
+        $this->assertSame($resolver, $loader->getResolver(), '->setResolver() sets the resolver loader');
+    }
+
+    /**
+     * @covers Symfony\Components\Routing\Loader\DelegatingLoader::supports
+     */
+    public function testSupports()
+    {
+        $resolver = new LoaderResolver(array(
+            $ini = new XmlFileLoader(array()),
+        ));
+        $loader = new DelegatingLoader($resolver);
+
+        $this->assertTrue($loader->supports('foo.xml'), '->supports() returns true if the resource is loadable');
+        $this->assertFalse($loader->supports('foo.foo'), '->supports() returns true if the resource is loadable');
+    }
+
+    /**
+     * @covers Symfony\Components\Routing\Loader\DelegatingLoader::load
+     */
+    public function testLoad()
+    {
+        $resolver = new LoaderResolver(array(
+            new ClosureLoader(),
+        ));
+        $loader = new DelegatingLoader($resolver);
+
+        $route = new Route('/');
+        $routes = $loader->load(function () use ($route)
+        {
+            $routes = new RouteCollection();
+
+            $routes->addRoute('foo', $route);
+
+            return $routes;
+        });
+
+        $this->assertSame($route, $routes->getRoute('foo'), '->load() loads a resource using the loaders from the resolver');
+
+        try {
+            $loader->load('foo.foo');
+            $this->fail('->load() throws an \InvalidArgumentException if the resource cannot be loaded');
+        } catch (\Exception $e) {
+            $this->assertInstanceOf('\InvalidArgumentException', $e, '->load() throws an \InvalidArgumentException if the resource cannot be loaded');
+        }
+    }
+}

tests/Symfony/Tests/Components/Routing/Loader/FileLoaderTest.php

@@ -0,0 +1,66 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Tests\Components\Routing\Loader;
+
+use Symfony\Components\Routing\Loader\FileLoader;
+
+class FileLoaderTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @covers Symfony\Components\Routing\Loader\FileLoader::__construct
+     */
+    public function testConstructor()
+    {
+        $loader = new ProjectLoader(__DIR__);
+        $this->assertEquals(array(__DIR__), $loader->paths, '__construct() takes a path as its second argument');
+
+        $loader = new ProjectLoader(array(__DIR__, __DIR__));
+        $this->assertEquals(array(__DIR__, __DIR__), $loader->paths, '__construct() takes an array of paths as its second argument');
+    }
+
+    /**
+     * @covers Symfony\Components\Routing\Loader\FileLoader::GetAbsolutePath
+     * @covers Symfony\Components\Routing\Loader\FileLoader::isAbsolutePath
+     */
+    public function testGetAbsolutePath()
+    {
+        $loader = new ProjectLoader(array(__DIR__.'/../Fixtures'));
+        $this->assertEquals('/foo.xml', $loader->getAbsolutePath('/foo.xml'), '->getAbsolutePath() return the path unmodified if it is already an absolute path');
+        $this->assertEquals('c:\\\\foo.xml', $loader->getAbsolutePath('c:\\\\foo.xml'), '->getAbsolutePath() return the path unmodified if it is already an absolute path');
+        $this->assertEquals('c:/foo.xml', $loader->getAbsolutePath('c:/foo.xml'), '->getAbsolutePath() return the path unmodified if it is already an absolute path');
+        $this->assertEquals('\\server\\foo.xml', $loader->getAbsolutePath('\\server\\foo.xml'), '->getAbsolutePath() return the path unmodified if it is already an absolute path');
+
+        $this->assertEquals(__DIR__.DIRECTORY_SEPARATOR.'FileLoaderTest.php', $loader->getAbsolutePath('FileLoaderTest.php', __DIR__), '->getAbsolutePath() returns an absolute filename if the file exists in the current path');
+
+        $this->assertEquals(__DIR__.'/../Fixtures/foo.xml', $loader->getAbsolutePath('foo.xml', __DIR__), '->getAbsolutePath() returns an absolute filename if the file exists in one of the paths given in the constructor');
+
+        $this->assertEquals('foobar.xml', $loader->getAbsolutePath('foobar.xml', __DIR__), '->getAbsolutePath() returns the path unmodified if it is unable to find it in the given paths');
+    }
+}
+
+class ProjectLoader extends FileLoader
+{
+    public $paths;
+
+    public function load($resource)
+    {
+    }
+
+    public function supports($resource)
+    {
+        return true;
+    }
+
+    public function getAbsolutePath($file, $currentPath = null)
+    {
+        return parent::getAbsolutePath($file, $currentPath);
+    }
+}

tests/Symfony/Tests/Components/Routing/Loader/LoaderResolverTest.php

@@ -0,0 +1,54 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Tests\Components\Routing\Loader;
+
+use Symfony\Components\Routing\Loader\LoaderResolver;
+use Symfony\Components\Routing\Loader\ClosureLoader;
+
+class LoaderResolverTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @covers Symfony\Components\Routing\Loader\LoaderResolver::__construct
+     */
+    public function testConstructor()
+    {
+        $resolver = new LoaderResolver(array(
+            $loader = new ClosureLoader(),
+        ));
+
+        $this->assertEquals(array($loader), $resolver->getLoaders(), '__construct() takes an array of loaders as its first argument');
+    }
+
+    /**
+     * @covers Symfony\Components\Routing\Loader\LoaderResolver::resolve
+     */
+    public function testResolve()
+    {
+        $resolver = new LoaderResolver(array(
+            $loader = new ClosureLoader(),
+        ));
+
+        $this->assertFalse($resolver->resolve('foo.foo'), '->resolve() returns false if no loader is able to load the resource');
+        $this->assertEquals($loader, $resolver->resolve(function () {}), '->resolve() returns the loader for the given resource');
+    }
+
+    /**
+     * @covers Symfony\Components\Routing\Loader\LoaderResolver::getLoaders
+     * @covers Symfony\Components\Routing\Loader\LoaderResolver::addLoader
+     */
+    public function testLoaders()
+    {
+        $resolver = new LoaderResolver();
+        $resolver->addLoader($loader = new ClosureLoader());
+
+        $this->assertEquals(array($loader), $resolver->getLoaders(), 'addLoader() adds a loader');
+    }
+}

tests/Symfony/Tests/Components/Routing/Loader/LoaderTest.php

@@ -0,0 +1,64 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Tests\Components\Routing\Loader;
+
+use Symfony\Components\Routing\Loader\LoaderResolver;
+use Symfony\Components\Routing\Loader\Loader;
+use Symfony\Components\Routing\Loader\XmlFileLoader;
+
+class LoaderTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @covers Symfony\Components\Routing\Loader\Loader::getResolver
+     * @covers Symfony\Components\Routing\Loader\Loader::setResolver
+     */
+    public function testGetSetResolver()
+    {
+        $resolver = new LoaderResolver();
+        $loader = new ProjectLoader1();
+        $loader->setResolver($resolver);
+        $this->assertSame($resolver, $loader->getResolver(), '->setResolver() sets the resolver loader');
+    }
+
+    /**
+     * @covers Symfony\Components\Routing\Loader\Loader::resolve
+     */
+    public function testResolve()
+    {
+        $resolver = new LoaderResolver(array(
+            $ini = new XmlFileLoader(array()),
+        ));
+        $loader = new ProjectLoader1();
+        $loader->setResolver($resolver);
+
+        $this->assertSame($ini, $loader->resolve('foo.xml'), '->resolve() finds a loader');
+        $this->assertSame($loader, $loader->resolve('foo.foo'), '->resolve() finds a loader');
+
+        try {
+            $loader->resolve(new \stdClass());
+            $this->fail('->resolve() throws an \InvalidArgumentException if the resource cannot be loaded');
+        } catch (\Exception $e) {
+            $this->assertInstanceOf('\InvalidArgumentException', $e, '->resolve() throws an \InvalidArgumentException if the resource cannot be loaded');
+        }
+    }
+}
+
+class ProjectLoader1 extends Loader
+{
+    public function load($resource)
+    {
+    }
+
+    public function supports($resource)
+    {
+        return is_string($resource) && 'foo' === pathinfo($resource, PATHINFO_EXTENSION);
+    }
+}