Fixes #3674: Various Twig enhancements:

docs/guide/tutorial-template-engines.md

@@ -82,6 +82,15 @@ In case you don't need result you shoud use `void` wrapper:
 {{ void(myObject.my_function({'a' : 'b'})) }}
 ```
 
+#### Setting object properties
+
+There's a special function called `set` that allows you to set property of an object. For example, the following
+in the template will change page title:
+
+```
+{{ set(this, 'title', 'New title') }}
+```
+
 #### Importing namespaces and classes
 
 You can import additional classes and namespaces right in the template:
@@ -97,6 +106,23 @@ Aliased class import:
 {{ use({'alias' => '/app/widgets/MyWidget'}) }}
 ```
 
+#### Referencing other views
+
+There are two ways of referencing views in `include` and `extends` statements:
+
+```
+{% include "comment.twig" %}
+{% extends "post.twig" %
+
+{% include "@app/views/snippets/avatar.twig" %}
+{% extends "@app/views/layouts/2columns.twig" %}
+```
+
+In the first case the view will be searched relatively to the path current view is in. For `comment.twig` and `post.twig`
+that means these will be searched in the same directory as the view that's rendered currently.
+
+In the second case we're using path aliases. All the Yii aliases such as `@app` are available by default.
+
 #### Widgets
 
 Extension helps using widgets in convenient way converting their syntax to function calls:

extensions/twig/CHANGELOG.md

@@ -8,6 +8,10 @@ Yii Framework 2 twig extension Change Log
 - Bug #3767: Fixed repeated adding of extensions when using config. One may now pass extension instances as well (grachov)
 - Bug #3877: Fixed `lexerOptions` throwing exception (dapatrese)
 - Enh #1799: Added `form_begin`, `form_end` to twig extension (samdark)
+- Enh #3674: Various enhancements (samdark)
+    - Removed `FileLoader` and used `\Twig_Loader_Filesystem` instead.
+    - Added support of Yii's aliases.
+    - Added `set()` that allows setting object properties.
 - Chg #3535: Syntax changes:
     - Removed `form_begin`, `form_end` (samdark)
     - Added `use()` and `ViewRenderer::uses` that are importing classes and namespaces (grachov, samdark)

extensions/twig/Extension.php

@@ -71,6 +71,7 @@ class Extension extends \Twig_Extension
             new \Twig_SimpleFunction('path', [$this, 'path']),
             new \Twig_SimpleFunction('url', [$this, 'url']),
             new \Twig_SimpleFunction('void', function(){}),
+            new \Twig_SimpleFunction('set', [$this, 'setProperty']),
         ];
 
         $options = array_merge($options, [
@@ -187,6 +188,11 @@ class Extension extends \Twig_Extension
         return Url::to(array_merge([$path], $args), true);
     }
 
+    public function setProperty($object, $property, $value)
+    {
+        $object->$property = $value;
+    }
+
     /**
      * @inheritdoc
      */

extensions/twig/FileLoader.php

-<?php
-/**
- * @link http://www.yiiframework.com/
- * @copyright Copyright (c) 2008 Yii Software LLC
- * @license http://www.yiiframework.com/license/
- */
-
-namespace yii\twig;
-
-/**
- * Twig view file loader class.
- *
- * @author dev-mraj <dev.meghraj@gmail.com>
- */
-class FileLoader implements \Twig_LoaderInterface
-{
-    /**
-     * @var string Path to directory
-     */
-    private $_dir;
-
-
-    /**
-     * @param string $dir path to directory
-     */
-    public function __construct($dir)
-    {
-        $this->_dir = $dir;
-    }
-
-    /**
-     * Compare a file's freshness with previously stored timestamp
-     *
-     * @param string $name file name to check
-     * @param integer $time timestamp to compare with
-     * @return boolean true if file is still fresh and not changes, false otherwise
-     */
-    public function isFresh($name, $time)
-    {
-        return filemtime($this->getFilePath($name)) <= $time;
-    }
-
-    /**
-     * Get the source of given file name
-     *
-     * @param string $name file name
-     * @return string contents of given file name
-     */
-    public function getSource($name)
-    {
-        return file_get_contents($this->getFilePath($name));
-    }
-
-    /**
-     * Get unique key that can represent this file uniquely among other files.
-     * @param string $name
-     * @return string
-     */
-    public function getCacheKey($name)
-    {
-        return $this->getFilePath($name);
-    }
-
-    /**
-     * internally used to get absolute path of given file name
-     * @param string $name file name
-     * @return string absolute path of file
-     */
-    protected function getFilePath($name)
-    {
-        return $this->_dir . '/' . $name;
-    }
-}

extensions/twig/ViewRenderer.php

@@ -143,7 +143,12 @@ class ViewRenderer extends BaseViewRenderer
     public function render($view, $file, $params)
     {
         $this->twig->addGlobal('this', $view);
-        $this->twig->setLoader(new FileLoader(dirname($file)));
+        $loader = new \Twig_Loader_Filesystem(dirname($file));
+
+        foreach (Yii::$aliases as $alias => $path) {
+            $loader->addPath($path, substr($alias, 1));
+        }
+        $this->twig->setLoader($loader);
 
         return $this->twig->render(pathinfo($file, PATHINFO_BASENAME), $params);
     }

tests/unit/extensions/twig/ViewRendererTest.php

@@ -69,6 +69,30 @@ class ViewRendererTest extends TestCase
         $this->assertTrue(strpos($content, 'variable') !== false, 'variable should be there:' . $content);
     }
 
+    public function testInheritance()
+    {
+        $view = $this->mockView();
+        $content = $view->renderFile('@yiiunit/extensions/twig/views/extends2.twig');
+        $this->assertTrue(strpos($content, 'Hello, I\'m inheritance test!') !== false, 'Hello, I\'m inheritance test! should be there:' . $content);
+        $this->assertTrue(strpos($content, 'extends2 block') !== false, 'extends2 block should be there:' . $content);
+        $this->assertFalse(strpos($content, 'extends1 block') !== false, 'extends1 block should not be there:' . $content);
+
+        $content = $view->renderFile('@yiiunit/extensions/twig/views/extends3.twig');
+        $this->assertTrue(strpos($content, 'Hello, I\'m inheritance test!') !== false, 'Hello, I\'m inheritance test! should be there:' . $content);
+        $this->assertTrue(strpos($content, 'extends3 block') !== false, 'extends3 block should be there:' . $content);
+        $this->assertFalse(strpos($content, 'extends1 block') !== false, 'extends1 block should not be there:' . $content);
+    }
+
+    public function testChangeTitle()
+    {
+        $view = $this->mockView();
+        $view->title = 'Original title';
+
+        $content = $view->renderFile('@yiiunit/extensions/twig/views/changeTitle.twig');
+        $this->assertTrue(strpos($content, 'New title') !== false, 'New title should be there:' . $content);
+        $this->assertFalse(strpos($content, 'Original title') !== false, 'Original title should not be there:' . $content);
+    }
+
     /**
      * Mocks view instance
      * @return View

tests/unit/extensions/twig/views/changeTitle.twig

+{{ set(this, 'title', 'New title') }}
+
+<title>{{ this.title }}</title>
\ No newline at end of file

tests/unit/extensions/twig/views/extends1.twig

+Hello, I'm inheritance test!
+
+{% block test %}
+extends1 block
+{% endblock %}
\ No newline at end of file

tests/unit/extensions/twig/views/extends2.twig

+{% extends "extends1.twig" %}
+
+{% block test %}
+extends2 block
+{% endblock %}
\ No newline at end of file

tests/unit/extensions/twig/views/extends3.twig

+{% extends "@yiiunit/extensions/twig/views/extends1.twig" %}
+
+{% block test %}
+extends3 block
+{% endblock %}
\ No newline at end of file