added a relative_path Twig function

CHANGELOG.md

@@ -4,7 +4,7 @@ CHANGELOG
 2.7.0
 -----
 
- * added an HttpFoundation extension (provides the `absolute_url` function)
+ * added an HttpFoundation extension (provides the `absolute_url` and the `relative_path` functions)
 
 2.5.0
 -----

Extension/HttpFoundationExtension.php

@@ -12,7 +12,7 @@
 namespace Symfony\Bridge\Twig\Extension;
 
 use Symfony\Component\HttpFoundation\RequestStack;
-use Symfony\Component\Asset\Packages;
+use Symfony\Component\HttpFoundation\Request;
 
 /**
  * Twig extension for the Symfony HttpFoundation component.
@@ -35,17 +35,20 @@ public function getFunctions()
     {
         return array(
             new \Twig_SimpleFunction('absolute_url', array($this, 'generateAbsoluteUrl')),
+            new \Twig_SimpleFunction('relative_path', array($this, 'generateRelativePath')),
         );
     }
 
     /**
-     * Returns the absolute URL for the given path.
+     * Returns the absolute URL for the given absolute or relative path.
      *
      * This method returns the path unchanged if no request is available.
      *
      * @param string $path The path
      *
      * @return string The absolute URL
+     *
+     * @see Request::getUriForPath()
      */
     public function generateAbsoluteUrl($path)
     {
@@ -57,9 +60,43 @@ public function generateAbsoluteUrl($path)
             return $path;
         }
 
+        if (!$path || '/' !== $path[0]) {
+            $prefix = $request->getPathInfo();
+            $last = strlen($prefix) - 1;
+            if ($last !== $pos = strrpos($prefix, '/')) {
+                $prefix = substr($prefix, 0, $pos).'/';
+            }
+
+            $path = $prefix.$path;
+        }
+
         return $request->getUriForPath($path);
     }
 
+    /**
+     * Returns a relative path based on the current Request.
+     *
+     * This method returns the path unchanged if no request is available.
+     *
+     * @param string $path The path
+     *
+     * @return string The relative path
+     *
+     * @see Request::getRelativeUriForPath()
+     */
+    public function generateRelativePath($path)
+    {
+        if (false !== strpos($path, '://') || '//' === substr($path, 0, 2)) {
+            return $path;
+        }
+
+        if (!$request = $this->requestStack->getMasterRequest()) {
+            return $path;
+        }
+
+        return $request->getRelativeUriForPath($path);
+    }
+
     /**
      * Returns the name of the extension.
      *

Tests/Extension/HttpFoundationExtensionTest.php

@@ -0,0 +1,74 @@
+<?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\Bridge\Twig\Tests\Extension;
+
+use Symfony\Bridge\Twig\Extension\HttpFoundationExtension;
+use Symfony\Component\HttpFoundation\RequestStack;
+use Symfony\Component\HttpFoundation\Request;
+
+class HttpFoundationExtensionTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @dataProvider getGenerateAbsoluteUrlData()
+     */
+    public function testGenerateAbsoluteUrl($expected, $path, $pathinfo)
+    {
+        $stack = new RequestStack();
+        $stack->push(Request::create($pathinfo));
+        $extension = new HttpFoundationExtension($stack);
+
+        $this->assertEquals($expected, $extension->generateAbsoluteUrl($path));
+    }
+
+    public function getGenerateAbsoluteUrlData()
+    {
+        return array(
+            array('http://localhost/foo.png', '/foo.png', '/foo/bar.html'),
+            array('http://localhost/foo/foo.png', 'foo.png', '/foo/bar.html'),
+            array('http://localhost/foo/foo.png', 'foo.png', '/foo/bar'),
+            array('http://localhost/foo/bar/foo.png', 'foo.png', '/foo/bar/'),
+
+            array('http://example.com/baz', 'http://example.com/baz', '/'),
+            array('https://example.com/baz', 'https://example.com/baz', '/'),
+            array('//example.com/baz', '//example.com/baz', '/'),
+        );
+    }
+
+    /**
+     * @dataProvider getGenerateRelativePathData()
+     */
+    public function testGenerateRelativePath($expected, $path, $pathinfo)
+    {
+        if (!method_exists('Symfony\Component\HttpFoundation\Request', 'getRelativeUriForPath')) {
+            $this->markTestSkipped('Your version of Symfony HttpFoundation is too old.');
+        }
+
+        $stack = new RequestStack();
+        $stack->push(Request::create($pathinfo));
+        $extension = new HttpFoundationExtension($stack);
+
+        $this->assertEquals($expected, $extension->generateRelativePath($path));
+    }
+
+    public function getGenerateRelativePathData()
+    {
+        return array(
+            array('../foo.png', '/foo.png', '/foo/bar.html'),
+            array('../baz/foo.png', '/baz/foo.png', '/foo/bar.html'),
+            array('baz/foo.png', 'baz/foo.png', '/foo/bar.html'),
+
+            array('http://example.com/baz', 'http://example.com/baz', '/'),
+            array('https://example.com/baz', 'https://example.com/baz', '/'),
+            array('//example.com/baz', '//example.com/baz', '/'),
+        );
+    }
+}