Issue #2114563 by joelpittet, martin107, Cottser: Remove TwigReference with...

Issue #2114563 by joelpittet, martin107, Cottser: Remove TwigReference with the help of 'without' filter replacing 'show'/'hide' functions.

core/lib/Drupal/Core/CoreServiceProvider.php

@@ -125,7 +125,6 @@ public static function registerTwig(ContainerBuilder $container) {
         // When in the installer, twig_cache must be FALSE until we know the
         // files folder is writable.
         'cache' => drupal_installation_attempted() ? FALSE : settings()->get('twig_cache', TRUE),
-        'base_template_class' => 'Drupal\Core\Template\TwigTemplate',
         // @todo Remove in followup issue
         // @see http://drupal.org/node/1712444.
         'autoescape' => FALSE,

core/lib/Drupal/Core/Template/TwigExtension.php

@@ -21,25 +21,24 @@ public function getFunctions() {
     // @todo re-add unset => twig_unset if this is really needed
     return array(
       // @todo Remove URL function once http://drupal.org/node/1778610 is resolved.
-      'url' => new \Twig_Function_Function('url'),
-      // These functions will receive a TwigReference object, if a render array is detected
-      'hide' => new TwigReferenceFunction('twig_hide'),
-      'render_var' => new TwigReferenceFunction('twig_render_var'),
-      'show' => new TwigReferenceFunction('twig_show'),
+      new \Twig_SimpleFunction('url', 'url'),
+      // This function will receive a renderable array, if an array is detected.
+      new \Twig_SimpleFunction('render_var', 'twig_render_var'),
     );
   }
 
   public function getFilters() {
     return array(
-      't' => new \Twig_Filter_Function('t'),
-      'trans' => new \Twig_Filter_Function('t'),
+      new \Twig_SimpleFilter('t', 't'),
+      new \Twig_SimpleFilter('trans', 't'),
       // The "raw" filter is not detectable when parsing "trans" tags. To detect
       // which prefix must be used for translation (@, !, %), we must clone the
       // "raw" filter and give it identifiable names. These filters should only
       // be used in "trans" tags.
       // @see TwigNodeTrans::compileString()
-      'passthrough' => new \Twig_Filter_Function('twig_raw_filter'),
-      'placeholder' => new \Twig_Filter_Function('twig_raw_filter'),
+      new \Twig_SimpleFilter('passthrough', 'twig_raw_filter'),
+      new \Twig_SimpleFilter('placeholder', 'twig_raw_filter'),
+      new \Twig_SimpleFilter('without', 'twig_without'),
     );
   }
 
@@ -53,8 +52,6 @@ public function getNodeVisitors() {
 
   public function getTokenParsers() {
     return array(
-      new TwigFunctionTokenParser('hide'),
-      new TwigFunctionTokenParser('show'),
       new TwigTransTokenParser(),
     );
   }

core/lib/Drupal/Core/Template/TwigNodeExpressionNameReference.php

-<?php
-
-/**
- * @file
- * Definition of Drupal\Core\Template\TwigNodeExpressionNameReference
- */
-
-namespace Drupal\Core\Template;
-
-/**
- * A class that defines a reference to the name for all nodes that represent
- * expressions.
- *
- * @see core\vendor\twig\twig\lib\Twig\Node\Expression\Name.php
- */
-class TwigNodeExpressionNameReference extends \Twig_Node_Expression_Name {
-
-  /**
-   * Overrides Twig_Node_Expression_Name::compile().
-   */
-  public function compile(\Twig_Compiler $compiler) {
-    $name = $this->getAttribute('name');
-    $compiler
-    ->raw('$this->getContextReference($context, ')
-    ->string($name)
-    ->raw(')');
-  }
-
-}

core/lib/Drupal/Core/Template/TwigNodeVisitor.php

@@ -19,36 +19,9 @@
 class TwigNodeVisitor implements \Twig_NodeVisitorInterface {
 
   /**
-   * TRUE when this node is a function getting arguments by reference.
-   *
-   * For example: 'hide' or 'render' are such functions.
-   *
-   * @var bool
-   */
-  protected $isReference = FALSE;
-
-  /**
-   * Implements Twig_NodeVisitorInterface::enterNode().
+   * {@inheritdoc}
    */
   function enterNode(\Twig_NodeInterface $node, \Twig_Environment $env) {
-   if ($node instanceof \Twig_Node_Expression_Function) {
-      $name = $node->getAttribute('name');
-      $func = $env->getFunction($name);
-
-      // Optimization: Do not support nested functions.
-      if ($this->isReference && $func instanceof \Twig_Function_Function) {
-        $this->isReference = FALSE;
-      }
-      if ($func instanceof TwigReferenceFunction) {
-        // We need to create a TwigReference
-        $this->isReference = TRUE;
-      }
-    }
-    if ($node instanceof \Twig_Node_Print) {
-       // Our injected render_var needs arguments passed by reference -- in case of render array
-      $this->isReference = TRUE;
-    }
-
     return $node;
   }
 
@@ -62,26 +35,14 @@ function enterNode(\Twig_NodeInterface $node, \Twig_Environment $env) {
    */
   function leaveNode(\Twig_NodeInterface $node, \Twig_Environment $env) {
     if ($node instanceof \Twig_Node_Print) {
-      $this->isReference = FALSE;
-
       $class = get_class($node);
+      $line = $node->getLine();
       return new $class(
-        new \Twig_Node_Expression_Function('render_var', new \Twig_Node(array($node->getNode('expr'))), $node->getLine()),
-        $node->getLine()
+        new \Twig_Node_Expression_Function('render_var', new \Twig_Node(array($node->getNode('expr'))), $line),
+        $line
       );
     }
 
-    if ($this->isReference) {
-      if ($node instanceof \Twig_Node_Expression_Name) {
-        $name = $node->getAttribute('name');
-        return new TwigNodeExpressionNameReference($name, $node->getLine());
-      }
-      elseif ($node instanceof \Twig_Function_Function) {
-        // Do something!
-        $this->isReference = FALSE;
-      }
-    }
-
     return $node;
   }
 

core/lib/Drupal/Core/Template/TwigReference.php

-<?php
-
-/**
- * @file
- * Definition of Drupal\Core\Template\TwigReference.
- */
-
-namespace Drupal\Core\Template;
-
-/**
- * A class used to pass variables by reference while they are used in twig.
- *
- * This is done by saving a reference to the original render array within a
- * TwigReference via the setReference() method like this:
- * @code
- * $obj = new TwigReference();
- * $obj->setReference($variable);
- * @endcode
- *
- * When a TwigReference is accessed via the offsetGet method the resulting
- * reference is again wrapped within a TwigReference. Therefore references to
- * render arrays within render arrays are also retained.
- *
- * To unwrap TwigReference objects the reference can be retrieved out of the
- * object by calling the getReference() method like this:
- * @code
- * $variable = &$obj->getReference();
- * @endcode
- * This allows render(), hide() and show() to access the original variable and
- * change it. The process of unwrapping and passing by reference to this
- * functions is done transparently by the TwigReferenceFunctions helper class.
- *
- * @see TwigReferenceFunction
- * @see TwigReferenceFunctions
- */
-class TwigReference extends \ArrayObject {
-
-  /**
-   * Holds an internal reference to the original array.
-   *
-   * @var array
-   */
-  protected $writableRef = array();
-
-  /**
-   * Constructs a \Drupal\Core\Template\TwigReference object.
-   *
-   * The argument to the constructor is ignored as it is not safe that this will
-   * always be a reference.
-   *
-   * To set a reference use:
-   * @code
-   * $obj = new TwigReference();
-   * $obj->setReference($variable);
-   * @endcode
-   *
-   * @param $array
-   *   The array parameter is ignored and not passed to the parent
-   */
-  public function __construct($array = NULL) {
-    parent::__construct();
-  }
-
-  /**
-   * Sets a reference in the internal storage.
-   *
-   * @param $array
-   *   The array to set as internal reference.
-   */
-  public function setReference(&$array) {
-    $this->exchangeArray($array);
-    $this->writableRef = &$array;
-  }
-
-  /**
-   * Gets a reference to the internal storage.
-   *
-   * Should be called like:
-   * @code
-   * $reference = &$obj->getReference();
-   * @endcode
-   *
-   * @return
-   *   Returns the stored internal reference.
-   */
-  public function &getReference() {
-    return $this->writableRef;
-  }
-
-  /**
-   * Sets offset in internal reference and internal storage to value.
-   *
-   * This is just for completeness, but should never be used, because
-   * twig cannot set properties and should not.
-   *
-   * @link http://php.net/manual/en/arrayaccess.offsetset.php
-   * @param mixed $offset
-   *   The offset to assign the value to.
-   * @param mixed $value
-   *   The value to set.
-   */
-  public function offsetSet($offset, $value) {
-    $this->writableRef[$offset] = $value;
-    parent::offsetSet($offset, $value);
-  }
-
-  /**
-   * Retrieves offset from internal reference.
-   *
-   * In case of a render array, it is wrapped again within a TwigReference
-   * object.
-   *
-   * @param mixed $offset
-   *   The offset to retrieve.
-   *
-   * @return mixed
-   *   Returns a TwigReference object wrapping the array if the retrieved offset
-   *   is a complex array (i.e. not an attribute). Else it returns the retrived
-   *   offset directly.
-   */
-  public function offsetGet($offset) {
-    if (!is_array($this->writableRef[$offset]) || $offset[0] == '#') {
-      return $this->writableRef[$offset];
-    }
-
-    // Wrap the returned array in a new TwigReference.
-    $x = clone $this; // clone is faster than new
-    $x->setReference($this->writableRef[$offset]);
-    return $x;
-  }
-}

core/lib/Drupal/Core/Template/TwigReferenceFunction.php

-<?php
-
-/**
- * @file
- * Definition of Drupal\Core\Template\TwigReferenceFunction.
- */
-
-namespace Drupal\Core\Template;
-
-/**
- * This class is used to create functions requiring references like 'hide'.
- */
-class TwigReferenceFunction extends \Twig_Function_Function {
-}

core/lib/Drupal/Core/Template/TwigReferenceFunctions.php

-<?php
-
-/**
- * @file
- * Definition of Drupal\Core\Template\TwigReferenceFunctions.
- */
-
-namespace Drupal\Core\Template;
-
-/**
- * A helper used to unwrap TwigReference objects transparently.
- *
- * This is providing a static magic function that makes it easier to unwrap
- * TwigReference objects and pass variables by reference to show(), hide() and
- * render().
- *
- * The problem is that twig passes variables only by value. The following is a
- * simplified version of the generated code by twig when the property "links" of
- * a render array stored in $content should be hidden:
- * @code
- * $_content_ = $content;
- * hide(getAttribute($_content_, 'links'));
- * @endcode
- * As hide() is operating on a copy of the original array the hidden property
- * is not set on the original $content variable.
- *
- * TwigReferenceFunctions can be used in combination with TwigReference to solve
- * this problem:
- * @code
- * // Internally getContextReference returns the array wrapped in a
- * // TwigReference if certain criteria are met
- * function getContextReference(&$content) {
- *   $obj = new Drupal\Core\Template\TwigReference();
- *   $obj->setReference($content);
- *   return $obj;
- * }
- *
- * // [...]
- * // Simplified, generated twig code
- * $_content_ = getContextReference($content);
- *
- * Drupal\Core\Template\TwigReferenceFunctions::hide(
- *   getAttribute($_content_, 'links')
- * );
- * @endcode
- * A TwigReference object is passed to the __callStatic function of
- * TwigReferenceFunctions. The method unwraps the TwigReference and calls the
- * hide() method essentially with a reference to $content['links'].
- *
- * Therefore the hidden property is correctly set and a successive call to
- * render() will not render the content twice.
- *
- * @see TwigReference
- * @see TwigReferenceFunction
- * @see TwigFactory
- *
- */
-class TwigReferenceFunctions {
-
-  /**
-   * Magic function to call functions called from twig templates with a
-   * reference to the original variable.
-   *
-   * This checks if the array provided by value is containing a reference to
-   * the original version. If yes it replaces the argument with its reference.
-   *
-   * @param $name
-   *   The name of the function to call.
-   * @param $arguments
-   *   The arguments to process and pass to the called function.
-   *
-   * @return mixed
-   *   Returns the output of the called function.
-   *
-   * @see TwigReference
-  */
-  public static function __callStatic($name, $arguments) {
-    foreach ($arguments as $key => $val) {
-      if (is_object($val) && $val instanceof TwigReference) {
-        $arguments[$key] = &$val->getReference();
-      }
-    }
-
-    // Needed to pass by reference -- could also restrict to maximum one
-    // argument instead
-    $args = array();
-    foreach ($arguments as $key => &$arg) {
-      $args[$key] = &$arg;
-    }
-
-    return call_user_func_array($name, $args);
-  }
-}

core/lib/Drupal/Core/Template/TwigTemplate.php

-<?php
-
-/**
- * @file
- * Definition of Drupal\Core\Template\TwigTemplate.
- */
-
-namespace Drupal\Core\Template;
-
-/**
- * This is the base class for compiled Twig templates.
- */
-abstract class TwigTemplate extends \Twig_Template {
-
-  /**
-   * A class used to pass variables by reference while they are used in Twig.
-   */
-  protected $twig_reference = NULL;
-
-  /**
-   * List of the name of variables to be passed around as references.
-   *
-   * @var array
-   */
-  protected $is_reference = array();
-
-  /**
-   * List of the name of variables to be passed around by value.
-   *
-   * @var array
-   */
-  protected $is_no_reference = array();
-
-  /**
-   * @param array $context
-   *   The variables available to the template.
-   * @param $item
-   *   The name of the variable.
-   * @return mixed
-   *   The requested variable.
-   */
-  protected function getContextReference(&$context, $item) {
-    // Optimized version. NULL is a valid value for $context[$item], we only
-    // want to error if it hasn't been defined at all.
-    if (!isset($context[$item]) && !array_key_exists($item, $context)) {
-      // We don't want to throw an exception, but issue a warning instead.
-      // This is the easiest way to do so.
-      // @todo Decide based on prod vs. dev setting
-      $msg = new \Twig_Error(t('@item could not be found in _context', array('@item' => $item)));
-      trigger_error($msg->getMessage(), E_USER_WARNING);
-      return NULL;
-    }
-
-    // Return item instead of its reference inside a loop.
-    // @todo 'hide' and 'show' are not supported inside a loop for now.
-    // This should be a non-issue as soon as this lands:
-    // @see http://drupal.org/node/1922304
-    if (isset($context['_seq'])) {
-      return $context[$item];
-    }
-
-    // The first test also finds empty / null render arrays
-    if (!$context[$item] || isset($this->is_no_reference[$item])) {
-      return $context[$item];
-    }
-
-    if (isset($context['_references'][$item])) {
-      return $context['_references'][$item];
-    }
-
-    // @todo Check if this is a render array (existence of #theme?)
-    if ((!isset($this->is_reference[$item])) && ($context[$item] instanceof \TwigMarkup || !is_array($context[$item]))) {
-      $this->is_no_reference[$item] = TRUE;
-      return $context[$item];
-    }
-
-    if ($this->twig_reference == NULL) {
-      $this->twig_reference = new TwigReference();
-    }
-    $ref = clone $this->twig_reference; // clone is _much_ faster than new
-    $ref->setReference($context[$item]);
-
-    // Save that this is a reference
-    $context['_references'][$item] = $ref;
-    $this->is_reference[$item] = TRUE;
-
-    return $ref;
-  }
-}

core/modules/block/templates/block-list.html.twig

@@ -13,10 +13,9 @@
  * @ingroup themeable
  */
 #}
-{% hide(form.place_blocks) %}
 <div class="layout-block-list clearfix">
   <div class="layout-region block-list-primary">
-    {{ form }}
+    {{ form|without('place_blocks') }}
   </div>
   <div class="layout-region block-list-secondary">
     {{ form.place_blocks }}

core/modules/comment/templates/comment.html.twig

@@ -7,8 +7,11 @@
  * - author: Comment author. Can be a link or plain text.
  * - content: The content-related items for the comment display. Use
  *   {{ content }} to print them all, or print a subset such as
- *   {{ content.field_example }}. Use hide(content.field_example) to temporarily
- *   suppress the printing of a given element.
+ *   {{ content.field_example }}. Use the following code to temporarily suppress
+ *   the printing of a given child element:
+ *   @code
+ *   {{ content|without('field_example') }}
+ *   @endcode
  * - created: Formatted date and time for when the comment was created.
  *   Preprocess functions can reformat it by calling format_date() with the
  *   desired parameters on the 'comment.created' variable.
@@ -92,9 +95,7 @@
   </footer>
 
   <div{{ content_attributes }}>
-    {# We hide the links now so that we can render them later. #}
-    {% hide(content.links) %}
-    {{ content }}
+    {{ content|without('links') }}
 
     {% if signature %}
       <div class="user-signature">

core/modules/node/templates/node-edit-form.html.twig

@@ -15,11 +15,9 @@
  * @ingroup themeable
  */
 #}
-{% hide(form.advanced) %}
-{% hide(form.actions) %}
 <div class="layout-node-form clearfix">
   <div class="layout-region layout-region-node-main">
-    {{ form }}
+    {{ form|without('advanced', 'actions') }}
   </div>
   <div class="layout-region layout-region-node-secondary">
     {{ form.advanced }}

core/modules/node/templates/node.html.twig

@@ -18,8 +18,8 @@
  * - label: The title of the node.
  * - content: All node items. Use {{ content }} to print them all,
  *   or print a subset such as {{ content.field_example }}. Use
- *   {% hide(content.field_example) %} to temporarily suppress the printing
- *   of a given element.
+ *   {{ content|without('field_example') %} to temporarily suppress the printing
+ *   of a given child element.
  * - user_picture: The node author's picture from user-picture.html.twig.
  * - date: Formatted creation date. Preprocess functions can reformat it by
  *   calling format_date() with the desired parameters on
@@ -93,9 +93,7 @@
   {% endif %}
 
   <div{{ content_attributes }}>
-    {# We hide links now so that we can render them later. #}
-    {% hide(content.links) %}
-    {{ content }}
+    {{ content|without('links') }}
   </div>
 
   {{ content.links }}

core/modules/system/lib/Drupal/system/Tests/Theme/TwigFilterTest.php

+<?php
+
+/**
+ * @file
+ * Contains \Drupal\system\Tests\Theme\TwigFilterTest.
+ */
+
+namespace Drupal\system\Tests\Theme;
+
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests Drupal's Twig filters.
+ */
+class TwigFilterTest extends WebTestBase {
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = array(
+    'twig_theme_test',
+  );
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function getInfo() {
+    return array(
+      'name' => 'Twig Filters',
+      'description' => 'Test Drupal\'s Twig filters.',
+      'group' => 'Theme',
+    );
+  }
+
+  /**
+   * Test Twig "without" filter.
+   */
+  public function testTwigWithoutFilter() {
+    $this->drupalGet('/twig-theme-test/filter');
+
+    $elements = array(
+      array(
+        'expected' => '<div><strong>No author:</strong> You can only find truth with logic if you have already found truth without it.1874-1936.</div>',
+        'message' => '"No author" was successfully rendered.',
+      ),
+      array(
+        'expected' => '<div><strong>Complete quote after without:</strong> You can only find truth with logic if you have already found truth without it.Gilbert Keith Chesterton1874-1936.</div>',
+        'message' => '"Complete quote after without" was successfully rendered.',
+      ),
+      array(
+        'expected' => '<div><strong>Only author:</strong> Gilbert Keith Chesterton.</div>',
+        'message' => '"Only author:" was successfully rendered.',
+      ),
+      array(
+        'expected' => '<div><strong>No author or date:</strong> You can only find truth with logic if you have already found truth without it..</div>',
+        'message' => '"No author or date" was successfully rendered.',
+      ),
+      array(
+        'expected' => '<div><strong>Only date:</strong> 1874-1936.</div>',
+        'message' => '"Only date" was successfully rendered.',
+      ),
+      array(
+        'expected' => '<div><strong>Complete quote again for good measure:</strong> You can only find truth with logic if you have already found truth without it.Gilbert Keith Chesterton1874-1936.</div>',
+        'message' => '"Complete quote again for good measure" was successfully rendered.',
+      ),
+      array(
+        'expected' => '<div><strong>Marked-up:</strong>
+  <blockquote>
+    <p>You can only find truth with logic if you have already found truth without it.</p>
+    <footer>
+      &ndash; <cite><a href="#">Gilbert Keith Chesterton</a> <em>(1874-1936)</em></cite>
+    </footer>
+  </blockquote>',
+        'message' => '"Marked-up quote" was successfully rendered.',
+      ),
+    );
+
+    foreach ($elements as $element) {
+      $this->assertRaw($element['expected'], $element['message']);
+    }
+  }
+
+}

core/modules/system/lib/Drupal/system/Tests/Theme/TwigReferenceObjectTest.php

-<?php
-
-/**
- * @file
- * Definition of Drupal\system\Tests\Theme\TwigReferenceObjectTest.
- */
-
-namespace Drupal\system\Tests\Theme;
-
-/**
- * TwigReferenceObjectTest class.
- */
-class TwigReferenceObjectTest {
-  public function __construct($nid, $title) {
-    $this->nid = $nid;
-    $this->title = $title;
-  }
-}

core/modules/system/lib/Drupal/system/Tests/Theme/TwigReferenceUnitTest.php

-<?php
-
-/**
- * @file
- * Definition of Drupal\system\Tests\Theme\TwigReferenceUnitTest.
- */
-
-namespace Drupal\system\Tests\Theme;
-
-use Drupal\simpletest\UnitTestBase;
-use Drupal\Core\Template\TwigReference;
-use Drupal\Core\Template\TwigReferenceFunctions;
-
-/**
- * Unit tests for TwigReference class.
- */
-class TwigReferenceUnitTest extends UnitTestBase {
-  public static function getInfo() {
-    return array(
-      'name' => 'Theme Twig References',
-      'description' => 'Tests TwigReference functions',
-      'group' => 'Theme',
-    );
-  }
-
-  function setUp() {
-    parent::setUp();
-    $this->variables = array(
-      'foo' => 'bar',
-      'baz' => array(
-        'foo' => '42',
-        'bar' => '23',
-      ),
-      'node' => new TwigReferenceObjectTest(
-        42,
-        'test node'
-      )
-    );
-  }
-
-  /**
-   * Test function for TwigReference class
-   */
-  function testTwigReference() {
-    // Create a new TwigReference wrapper
-    $wrapper = new TwigReference();
-    $wrapper->setReference($this->variables);
-
-    // Check that strings are returned as strings
-    $foo = $wrapper['foo'];
-    $this->assertEqual($foo, $this->variables['foo'], 'String returned from TwigReference is the same');
-    $this->assertTrue(is_string($foo), 'String returned from TwigReference is of type string');
-
-    // Check that arrays are wrapped again as TwigReference objects
-    $baz = $wrapper['baz'];
-    $this->assertTrue(is_object($baz), 'Array returned from TwigReference is of type object');
-    $this->assertTrue($baz instanceof TwigReference, 'Array returned from TwigReference is instance of TwigReference');
-
-    // Check that getReference is giving back a reference to the original array
-
-    $ref = &$baz->getReference();
-    $this->assertTrue(is_array($ref), 'getReference returns an array');
-
-    // Now modify $ref
-    $ref['#hidden'] = TRUE;
-    $this->assertEqual($ref['#hidden'], $this->variables['baz']['#hidden'], 'Property set on reference is passed to original array.');
-    $this->assertEqual($ref['#hidden'], $baz['#hidden'], 'Property set on reference is passed to wrapper.');
-
-    // Now modify $baz
-    $baz['hi'] = 'hello';
-
-    $this->assertEqual($baz['hi'], $this->variables['baz']['hi'], 'Property set on TwigReference object is passed to original array.');
-    $this->assertEqual($baz['hi'], $ref['hi'], 'Property set on TwigReference object is passed to reference.');
-
-    // Check that an object is passed through directly
-    $node = $wrapper['node'];
-    $this->assertTrue(is_object($node), 'Object returned from TwigReference is of type object');
-    $this->assertTrue($node instanceof TwigReferenceObjectTest, 'Object returned from TwigReference is instance of TwigReferenceObjectTest');
-  }
-
-  /**
-   * Test function for TwigReferenceFunctions class
-   */
-  function testTwigReferenceFunctions() {
-
-    // Create wrapper
-    $content = &$this->variables;
-
-    // Use twig nomenclature
-    $context['content'] = $content;
-
-    // Twig converts {{ hide(content.baz) }} to the following code
-
-    // This will have failed, because getAttribute returns a value and not a reference
-
-    try {
-      if (isset($context["content"])) {
-        $_content_ = $context["content"];
-      }
-      else {
-        $_content_ = NULL;
-      }
-      TwigReferenceFunctions::hide($this->getAttribute($_content_, "baz"));
-    }
-    catch (Exception $e) {
-      // Catch the critical warning that a value was passed by reference
-    }
-    $this->assertFalse(isset($content['baz']['#printed']), 'baz is not hidden in content after hide() via value');
-
-    // Now lets do the same with some TwigReference magic!
-
-    $content_wrapper = new TwigReference();
-    $content_wrapper->setReference($content);
-    $context['content'] = $content_wrapper;
-
-    // Twig converts {{ hide(content.baz) }} to the following code
-
-    // This will succeed, because getAttribute returns a value, but it is an object
-
-    if (isset($context["content"])) {
-      $_content_ = $context["content"];
-    }
-    else {
-      $_content_ = NULL;
-    }
-    TwigReferenceFunctions::hide($this->getAttribute($_content_, "baz"));
-
-    $this->assertTrue(isset($content['baz']['#printed']), 'baz is hidden in content after hide() via TwigReference object');
-
-    $type = TwigReferenceFunctions::gettype($this->getAttribute($_content_, "baz"));
-    $this->assertEqual($type, 'array', 'Type returned via TwigReferenceFunctions:: is an array.');
-
-    $type = gettype($this->getAttribute($_content_, "baz"));
-    $this->assertEqual($type, 'object', 'Type returned without TwigReferenceFunctions:: is an object.');
-  }
-
-  /**
-   *  Helper function to somehow simulate Twigs getAttribute function
-   */
-  public function getAttribute($array, $offset) {
-    if (isset($array[$offset])) {
-      return $array[$offset];
-    }
-
-    return NULL;
-  }
-}

core/modules/system/tests/modules/twig_extension_test/lib/Drupal/twig_extension_test/TwigExtension/TestExtension.php

@@ -8,7 +8,6 @@
 namespace Drupal\twig_extension_test\TwigExtension;
 
 use Drupal\Core\Template\TwigExtension;
-use Drupal\Core\Template\TwigReferenceFunction;
 
 /**
  * A test Twig extension that adds a custom function and a custom filter.

core/modules/system/tests/modules/twig_theme_test/lib/Drupal/twig_theme_test/TwigThemeTestController.php

@@ -28,4 +28,19 @@ public function transBlockRender() {
     );
   }
 
+  /**
+   * Menu callback for filters in a Twig template.
+   */
+  public function testFilterRender() {
+    return array(
+      '#theme' => 'twig_theme_test_filter',
+      '#quote' => array(
+        'content' => array('#markup' => 'You can only find truth with logic if you have already found truth without it.'),
+        'author' => array('#markup' => 'Gilbert Keith Chesterton'),
+        'date' => array('#markup' => '1874-1936'),
+      ),
+    );
+  }
+
 }
+

core/modules/system/tests/modules/twig_theme_test/templates/twig_theme_test.filter.html.twig

+<div><strong>No author:</strong> {{ quote|without('author') }}.</div>
+<div><strong>Complete quote after without:</strong> {{ quote }}.</div>
+<div><strong>Only author:</strong> {{ quote.author }}.</div>
+<div><strong>No author or date:</strong> {{ quote|without('date', 'author') }}.</div>
+<div><strong>Only date:</strong> {{ quote.date }}.</div>
+<div><strong>Complete quote again for good measure:</strong> {{ quote }}.</div>
+<div><strong>Marked-up:</strong>
+  <blockquote>
+    <p>{{ quote.content }}</p>
+    <footer>
+      &ndash; <cite><a href="#">{{ quote.author }}</a> <em>({{ quote.date }})</em></cite>
+    </footer>
+  </blockquote>
+</div>

core/modules/system/tests/modules/twig_theme_test/twig_theme_test.module

@@ -4,6 +4,10 @@
  * Implements hook_theme().
  */
 function twig_theme_test_theme($existing, $type, $theme, $path) {
+  $items['twig_theme_test_filter'] = array(
+    'variables' => array('quote' => array()),
+    'template' => 'twig_theme_test.filter',
+  );
   $items['twig_theme_test_php_variables'] = array(
     'template' => 'twig_theme_test.php_variables',
   );

core/modules/system/tests/modules/twig_theme_test/twig_theme_test.routing.yml

@@ -11,3 +11,10 @@ twig_theme_test.trans:
     _content: '\Drupal\twig_theme_test\TwigThemeTestController::transBlockRender'
   requirements:
     _access: 'TRUE'
+
+twig_theme_test.filter:
+  path: '/twig-theme-test/filter'
+  defaults:
+    _content: '\Drupal\twig_theme_test\TwigThemeTestController::testFilterRender'
+  requirements:
+    _access: 'TRUE'