added a way to render a controller from a template (like in Symfony2)

doc/extensions/twig.rst

@@ -62,16 +62,23 @@ The Twig extension provides a ``twig`` service::
 
 This will render a file named ``views/hello.twig``.
 
-.. tip::
+In any Twig template, the ``app`` variable refers to the Application object.
+So you can access any services from within your view. For example to access
+``$app['request']->getHost()``, just put this in your template:
 
-    The TwigExtension also registers the application as a global
-    named ``app``. So you can access any services from within your
-    view. For example to access ``$app['request']->getHost()``,
-    just put this in your template:
-
-    .. code-block:: jinja
+.. code-block:: jinja
 
     {{ app.request.host }}
 
+A ``render`` function is also register to help you render another controller
+from a template:
+
+.. code-block:: jinja
+
+    {{ render('/sidebar') }}
+
+    {# or if you are also using UrlGeneratorExtension #}
+    {{ render(path('sidebar')) }}
+
 For more information, check out the `Twig documentation
 <http://twig.sensiolabs.org>`_.

src/Silex/Extension/TwigCoreExtension.php

+<?php
+
+/*
+ * This file is part of the Silex framework.
+ *
+ * (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 Silex\Extension;
+
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\HttpKernelInterface;
+
+/**
+ * Twig extension.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class TwigCoreExtension extends \Twig_Extension
+{
+    public function getFunctions()
+    {
+        return array(
+            'render' => new \Twig_Function_Method($this, 'render', array('needs_environment' => true, 'is_safe' => array('html'))),
+        );
+    }
+
+    public function render(\Twig_Environment $twig, $uri)
+    {
+        $globals = $twig->getGlobals();
+        $request = $globals['app']['request'];
+
+        $subRequest = Request::create($uri, 'get', array(), $request->cookies->all(), array(), $request->server->all());
+        if ($request->getSession()) {
+            $subRequest->setSession($request->getSession());
+        }
+
+        $response = $globals['app']->handle($subRequest, HttpKernelInterface::SUB_REQUEST, false);
+
+        if (!$response->isSuccessful()) {
+            throw new \RuntimeException(sprintf('Error when rendering "%s" (Status code is %s).', $request->getUri(), $response->getStatusCode()));
+        }
+
+        return $response->getContent();
+    }
+
+    public function getName()
+    {
+        return 'silex';
+    }
+}

src/Silex/Extension/TwigExtension.php

@@ -39,6 +39,7 @@ class TwigExtension implements ExtensionInterface
 
             $twig = new \Twig_Environment($app['twig.loader'], $app['twig.options']);
             $twig->addGlobal('app', $app);
+            $twig->addExtension(new TwigCoreExtension());
 
             if (isset($app['symfony_bridges'])) {
                 if (isset($app['url_generator'])) {

tests/Silex/Tests/Extension/TwigExtensionTest.php

@@ -47,4 +47,29 @@ class TwigExtensionTest extends \PHPUnit_Framework_TestCase
         $response = $app->handle($request);
         $this->assertEquals('Hello john!', $response->getContent());
     }
+
+    public function testRenderFunction()
+    {
+        $app = new Application();
+
+        $app->register(new TwigExtension(), array(
+            'twig.templates'    => array(
+                'hello' => '{{ render("/foo") }}',
+                'foo'   => 'foo',
+            ),
+            'twig.class_path'   => __DIR__.'/../../../../vendor/twig/lib',
+        ));
+
+        $app->get('/hello', function () use ($app) {
+            return $app['twig']->render('hello');
+        });
+
+        $app->get('/foo', function () use ($app) {
+            return $app['twig']->render('foo');
+        });
+
+        $request = Request::create('/hello');
+        $response = $app->handle($request);
+        $this->assertEquals('foo', $response->getContent());
+    }
 }