Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\Core\Template;
Chris@0: 
Chris@0: use Drupal\Component\Utility\Html;
Chris@0: use Drupal\Component\Render\MarkupInterface;
Chris@0: use Drupal\Core\Cache\CacheableDependencyInterface;
Chris@0: use Drupal\Core\Datetime\DateFormatterInterface;
Chris@0: use Drupal\Core\Render\AttachmentsInterface;
Chris@0: use Drupal\Core\Render\BubbleableMetadata;
Chris@0: use Drupal\Core\Render\Markup;
Chris@0: use Drupal\Core\Render\RenderableInterface;
Chris@0: use Drupal\Core\Render\RendererInterface;
Chris@0: use Drupal\Core\Routing\UrlGeneratorInterface;
Chris@0: use Drupal\Core\Theme\ThemeManagerInterface;
Chris@0: use Drupal\Core\Url;
Chris@0: 
Chris@0: /**
Chris@0:  * A class providing Drupal Twig extensions.
Chris@0:  *
Chris@0:  * This provides a Twig extension that registers various Drupal-specific
Chris@0:  * extensions to Twig, specifically Twig functions, filter, and node visitors.
Chris@0:  *
Chris@0:  * @see \Drupal\Core\CoreServiceProvider
Chris@0:  */
Chris@0: class TwigExtension extends \Twig_Extension {
Chris@0: 
Chris@0:   /**
Chris@0:    * The URL generator.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\Routing\UrlGeneratorInterface
Chris@0:    */
Chris@0:   protected $urlGenerator;
Chris@0: 
Chris@0:   /**
Chris@0:    * The renderer.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\Render\RendererInterface
Chris@0:    */
Chris@0:   protected $renderer;
Chris@0: 
Chris@0:   /**
Chris@0:    * The theme manager.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\Theme\ThemeManagerInterface
Chris@0:    */
Chris@0:   protected $themeManager;
Chris@0: 
Chris@0:   /**
Chris@0:    * The date formatter.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\Datetime\DateFormatterInterface
Chris@0:    */
Chris@0:   protected $dateFormatter;
Chris@0: 
Chris@0:   /**
Chris@0:    * Constructs \Drupal\Core\Template\TwigExtension.
Chris@0:    *
Chris@0:    * @param \Drupal\Core\Render\RendererInterface $renderer
Chris@0:    *   The renderer.
Chris@0:    * @param \Drupal\Core\Routing\UrlGeneratorInterface $url_generator
Chris@0:    *   The URL generator.
Chris@0:    * @param \Drupal\Core\Theme\ThemeManagerInterface $theme_manager
Chris@0:    *   The theme manager.
Chris@0:    * @param \Drupal\Core\Datetime\DateFormatterInterface $date_formatter
Chris@0:    *   The date formatter.
Chris@0:    */
Chris@0:   public function __construct(RendererInterface $renderer, UrlGeneratorInterface $url_generator, ThemeManagerInterface $theme_manager, DateFormatterInterface $date_formatter) {
Chris@0:     $this->renderer = $renderer;
Chris@0:     $this->urlGenerator = $url_generator;
Chris@0:     $this->themeManager = $theme_manager;
Chris@0:     $this->dateFormatter = $date_formatter;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Sets the URL generator.
Chris@0:    *
Chris@0:    * @param \Drupal\Core\Routing\UrlGeneratorInterface $url_generator
Chris@0:    *   The URL generator.
Chris@0:    *
Chris@0:    * @return $this
Chris@0:    *
Chris@0:    * @deprecated in Drupal 8.0.x-dev, will be removed before Drupal 9.0.0.
Chris@0:    */
Chris@0:   public function setGenerators(UrlGeneratorInterface $url_generator) {
Chris@0:     return $this->setUrlGenerator($url_generator);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Sets the URL generator.
Chris@0:    *
Chris@0:    * @param \Drupal\Core\Routing\UrlGeneratorInterface $url_generator
Chris@0:    *   The URL generator.
Chris@0:    *
Chris@0:    * @return $this
Chris@0:    *
Chris@0:    * @deprecated in Drupal 8.3.x-dev, will be removed before Drupal 9.0.0.
Chris@0:    */
Chris@0:   public function setUrlGenerator(UrlGeneratorInterface $url_generator) {
Chris@0:     $this->urlGenerator = $url_generator;
Chris@0:     return $this;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Sets the theme manager.
Chris@0:    *
Chris@0:    * @param \Drupal\Core\Theme\ThemeManagerInterface $theme_manager
Chris@0:    *   The theme manager.
Chris@0:    *
Chris@0:    * @return $this
Chris@0:    *
Chris@0:    * @deprecated in Drupal 8.3.x-dev, will be removed before Drupal 9.0.0.
Chris@0:    */
Chris@0:   public function setThemeManager(ThemeManagerInterface $theme_manager) {
Chris@0:     $this->themeManager = $theme_manager;
Chris@0:     return $this;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Sets the date formatter.
Chris@0:    *
Chris@0:    * @param \Drupal\Core\Datetime\DateFormatter $date_formatter
Chris@0:    *   The date formatter.
Chris@0:    *
Chris@0:    * @return $this
Chris@0:    *
Chris@0:    * @deprecated in Drupal 8.3.x-dev, will be removed before Drupal 9.0.0.
Chris@0:    */
Chris@0:   public function setDateFormatter(DateFormatterInterface $date_formatter) {
Chris@0:     $this->dateFormatter = $date_formatter;
Chris@0:     return $this;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function getFunctions() {
Chris@0:     return [
Chris@0:       // This function will receive a renderable array, if an array is detected.
Chris@0:       new \Twig_SimpleFunction('render_var', [$this, 'renderVar']),
Chris@0:       // The url and path function are defined in close parallel to those found
Chris@0:       // in \Symfony\Bridge\Twig\Extension\RoutingExtension
Chris@0:       new \Twig_SimpleFunction('url', [$this, 'getUrl'], ['is_safe_callback' => [$this, 'isUrlGenerationSafe']]),
Chris@0:       new \Twig_SimpleFunction('path', [$this, 'getPath'], ['is_safe_callback' => [$this, 'isUrlGenerationSafe']]),
Chris@0:       new \Twig_SimpleFunction('link', [$this, 'getLink']),
Chris@0:       new \Twig_SimpleFunction('file_url', function ($uri) {
Chris@0:         return file_url_transform_relative(file_create_url($uri));
Chris@0:       }),
Chris@0:       new \Twig_SimpleFunction('attach_library', [$this, 'attachLibrary']),
Chris@0:       new \Twig_SimpleFunction('active_theme_path', [$this, 'getActiveThemePath']),
Chris@0:       new \Twig_SimpleFunction('active_theme', [$this, 'getActiveTheme']),
Chris@0:       new \Twig_SimpleFunction('create_attribute', [$this, 'createAttribute']),
Chris@0:     ];
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function getFilters() {
Chris@0:     return [
Chris@0:       // Translation filters.
Chris@0:       new \Twig_SimpleFilter('t', 't', ['is_safe' => ['html']]),
Chris@0:       new \Twig_SimpleFilter('trans', 't', ['is_safe' => ['html']]),
Chris@0:       // The "raw" filter is not detectable when parsing "trans" tags. To detect
Chris@0:       // which prefix must be used for translation (@, !, %), we must clone the
Chris@0:       // "raw" filter and give it identifiable names. These filters should only
Chris@0:       // be used in "trans" tags.
Chris@0:       // @see TwigNodeTrans::compileString()
Chris@0:       new \Twig_SimpleFilter('placeholder', [$this, 'escapePlaceholder'], ['is_safe' => ['html'], 'needs_environment' => TRUE]),
Chris@0: 
Chris@0:       // Replace twig's escape filter with our own.
Chris@0:       new \Twig_SimpleFilter('drupal_escape', [$this, 'escapeFilter'], ['needs_environment' => TRUE, 'is_safe_callback' => 'twig_escape_filter_is_safe']),
Chris@0: 
Chris@0:       // Implements safe joining.
Chris@0:       // @todo Make that the default for |join? Upstream issue:
Chris@0:       //   https://github.com/fabpot/Twig/issues/1420
Chris@0:       new \Twig_SimpleFilter('safe_join', [$this, 'safeJoin'], ['needs_environment' => TRUE, 'is_safe' => ['html']]),
Chris@0: 
Chris@0:       // Array filters.
Chris@18:       new \Twig_SimpleFilter('without', [$this, 'withoutFilter']),
Chris@0: 
Chris@0:       // CSS class and ID filters.
Chris@0:       new \Twig_SimpleFilter('clean_class', '\Drupal\Component\Utility\Html::getClass'),
Chris@0:       new \Twig_SimpleFilter('clean_id', '\Drupal\Component\Utility\Html::getId'),
Chris@0:       // This filter will render a renderable array to use the string results.
Chris@0:       new \Twig_SimpleFilter('render', [$this, 'renderVar']),
Chris@0:       new \Twig_SimpleFilter('format_date', [$this->dateFormatter, 'format']),
Chris@0:     ];
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function getNodeVisitors() {
Chris@0:     // The node visitor is needed to wrap all variables with
Chris@0:     // render_var -> TwigExtension->renderVar() function.
Chris@0:     return [
Chris@0:       new TwigNodeVisitor(),
Chris@0:     ];
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function getTokenParsers() {
Chris@0:     return [
Chris@0:       new TwigTransTokenParser(),
Chris@0:     ];
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function getName() {
Chris@0:     return 'drupal_core';
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Generates a URL path given a route name and parameters.
Chris@0:    *
Chris@0:    * @param $name
Chris@0:    *   The name of the route.
Chris@0:    * @param array $parameters
Chris@0:    *   An associative array of route parameters names and values.
Chris@0:    * @param array $options
Chris@0:    *   (optional) An associative array of additional options. The 'absolute'
Chris@0:    *   option is forced to be FALSE.
Chris@0:    *
Chris@0:    * @return string
Chris@0:    *   The generated URL path (relative URL) for the given route.
Chris@0:    *
Chris@0:    * @see \Drupal\Core\Routing\UrlGeneratorInterface::generateFromRoute()
Chris@0:    */
Chris@0:   public function getPath($name, $parameters = [], $options = []) {
Chris@18:     assert($this->urlGenerator instanceof UrlGeneratorInterface, "The URL generator hasn't been set up. Any configuration YAML file with a service directive dealing with the Twig configuration can cause this, most likely found in a recently installed or changed module.");
Chris@18: 
Chris@0:     $options['absolute'] = FALSE;
Chris@0:     return $this->urlGenerator->generateFromRoute($name, $parameters, $options);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Generates an absolute URL given a route name and parameters.
Chris@0:    *
Chris@0:    * @param $name
Chris@0:    *   The name of the route.
Chris@0:    * @param array $parameters
Chris@0:    *   An associative array of route parameter names and values.
Chris@0:    * @param array $options
Chris@0:    *   (optional) An associative array of additional options. The 'absolute'
Chris@0:    *   option is forced to be TRUE.
Chris@0:    *
Chris@0:    * @return string
Chris@0:    *   The generated absolute URL for the given route.
Chris@0:    *
Chris@0:    * @todo Add an option for scheme-relative URLs.
Chris@0:    */
Chris@0:   public function getUrl($name, $parameters = [], $options = []) {
Chris@18:     assert($this->urlGenerator instanceof UrlGeneratorInterface, "The URL generator hasn't been set up. Any configuration YAML file with a service directive dealing with the Twig configuration can cause this, most likely found in a recently installed or changed module.");
Chris@18: 
Chris@0:     // Generate URL.
Chris@0:     $options['absolute'] = TRUE;
Chris@0:     $generated_url = $this->urlGenerator->generateFromRoute($name, $parameters, $options, TRUE);
Chris@0: 
Chris@0:     // Return as render array, so we can bubble the bubbleable metadata.
Chris@0:     $build = ['#markup' => $generated_url->getGeneratedUrl()];
Chris@0:     $generated_url->applyTo($build);
Chris@0:     return $build;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Gets a rendered link from a url object.
Chris@0:    *
Chris@0:    * @param string $text
Chris@0:    *   The link text for the anchor tag as a translated string.
Chris@0:    * @param \Drupal\Core\Url|string $url
Chris@0:    *   The URL object or string used for the link.
Chris@0:    * @param array|\Drupal\Core\Template\Attribute $attributes
Chris@0:    *   An optional array or Attribute object of link attributes.
Chris@0:    *
Chris@0:    * @return array
Chris@0:    *   A render array representing a link to the given URL.
Chris@0:    */
Chris@0:   public function getLink($text, $url, $attributes = []) {
Chris@18:     assert(is_string($url) || $url instanceof Url, '$url must be a string or object of type \Drupal\Core\Url');
Chris@18:     assert(is_array($attributes) || $attributes instanceof Attribute, '$attributes, if set, must be an array or object of type \Drupal\Core\Template\Attribute');
Chris@18: 
Chris@0:     if (!$url instanceof Url) {
Chris@0:       $url = Url::fromUri($url);
Chris@0:     }
Chris@0:     // The twig extension should not modify the original URL object, this
Chris@0:     // ensures consistent rendering.
Chris@0:     // @see https://www.drupal.org/node/2842399
Chris@0:     $url = clone $url;
Chris@0:     if ($attributes) {
Chris@0:       if ($attributes instanceof Attribute) {
Chris@0:         $attributes = $attributes->toArray();
Chris@0:       }
Chris@0:       $url->mergeOptions(['attributes' => $attributes]);
Chris@0:     }
Chris@0:     // The text has been processed by twig already, convert it to a safe object
Chris@0:     // for the render system.
Chris@0:     if ($text instanceof \Twig_Markup) {
Chris@0:       $text = Markup::create($text);
Chris@0:     }
Chris@0:     $build = [
Chris@0:       '#type' => 'link',
Chris@0:       '#title' => $text,
Chris@0:       '#url' => $url,
Chris@0:     ];
Chris@0:     return $build;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Gets the name of the active theme.
Chris@0:    *
Chris@0:    * @return string
Chris@0:    *   The name of the active theme.
Chris@0:    */
Chris@0:   public function getActiveTheme() {
Chris@0:     return $this->themeManager->getActiveTheme()->getName();
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Gets the path of the active theme.
Chris@0:    *
Chris@0:    * @return string
Chris@0:    *   The path to the active theme.
Chris@0:    */
Chris@0:   public function getActiveThemePath() {
Chris@0:     return $this->themeManager->getActiveTheme()->getPath();
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Determines at compile time whether the generated URL will be safe.
Chris@0:    *
Chris@0:    * Saves the unneeded automatic escaping for performance reasons.
Chris@0:    *
Chris@0:    * The URL generation process percent encodes non-alphanumeric characters.
Chris@0:    * Thus, the only character within a URL that must be escaped in HTML is the
Chris@0:    * ampersand ("&") which separates query params. Thus we cannot mark
Chris@0:    * the generated URL as always safe, but only when we are sure there won't be
Chris@0:    * multiple query params. This is the case when there are none or only one
Chris@0:    * constant parameter given. For instance, we know beforehand this will not
Chris@0:    * need to be escaped:
Chris@0:    * - path('route')
Chris@0:    * - path('route', {'param': 'value'})
Chris@0:    * But the following may need to be escaped:
Chris@0:    * - path('route', var)
Chris@0:    * - path('route', {'param': ['val1', 'val2'] }) // a sub-array
Chris@0:    * - path('route', {'param1': 'value1', 'param2': 'value2'})
Chris@0:    * If param1 and param2 reference placeholders in the route, it would not
Chris@0:    * need to be escaped, but we don't know that in advance.
Chris@0:    *
Chris@0:    * @param \Twig_Node $args_node
Chris@0:    *   The arguments of the path/url functions.
Chris@0:    *
Chris@0:    * @return array
Chris@0:    *   An array with the contexts the URL is safe
Chris@0:    */
Chris@0:   public function isUrlGenerationSafe(\Twig_Node $args_node) {
Chris@0:     // Support named arguments.
Chris@0:     $parameter_node = $args_node->hasNode('parameters') ? $args_node->getNode('parameters') : ($args_node->hasNode(1) ? $args_node->getNode(1) : NULL);
Chris@0: 
Chris@0:     if (!isset($parameter_node) || $parameter_node instanceof \Twig_Node_Expression_Array && count($parameter_node) <= 2 &&
Chris@0:         (!$parameter_node->hasNode(1) || $parameter_node->getNode(1) instanceof \Twig_Node_Expression_Constant)) {
Chris@0:       return ['html'];
Chris@0:     }
Chris@0: 
Chris@0:     return [];
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Attaches an asset library to the template, and hence to the response.
Chris@0:    *
Chris@0:    * Allows Twig templates to attach asset libraries using
Chris@0:    * @code
Chris@0:    * {{ attach_library('extension/library_name') }}
Chris@0:    * @endcode
Chris@0:    *
Chris@0:    * @param string $library
Chris@0:    *   An asset library.
Chris@0:    */
Chris@0:   public function attachLibrary($library) {
Chris@18:     assert(is_string($library), 'Argument must be a string.');
Chris@18: 
Chris@0:     // Use Renderer::render() on a temporary render array to get additional
Chris@0:     // bubbleable metadata on the render stack.
Chris@0:     $template_attached = ['#attached' => ['library' => [$library]]];
Chris@0:     $this->renderer->render($template_attached);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Provides a placeholder wrapper around ::escapeFilter.
Chris@0:    *
Chris@0:    * @param \Twig_Environment $env
Chris@0:    *   A Twig_Environment instance.
Chris@0:    * @param mixed $string
Chris@0:    *   The value to be escaped.
Chris@0:    *
Chris@0:    * @return string|null
Chris@0:    *   The escaped, rendered output, or NULL if there is no valid output.
Chris@0:    */
Chris@18:   public function escapePlaceholder(\Twig_Environment $env, $string) {
Chris@18:     $return = $this->escapeFilter($env, $string);
Chris@18: 
Chris@18:     return $return ? '<em class="placeholder">' . $return . '</em>' : NULL;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Overrides twig_escape_filter().
Chris@0:    *
Chris@0:    * Replacement function for Twig's escape filter.
Chris@0:    *
Chris@0:    * Note: This function should be kept in sync with
Chris@0:    * theme_render_and_autoescape().
Chris@0:    *
Chris@0:    * @param \Twig_Environment $env
Chris@0:    *   A Twig_Environment instance.
Chris@0:    * @param mixed $arg
Chris@0:    *   The value to be escaped.
Chris@0:    * @param string $strategy
Chris@0:    *   The escaping strategy. Defaults to 'html'.
Chris@0:    * @param string $charset
Chris@0:    *   The charset.
Chris@0:    * @param bool $autoescape
Chris@0:    *   Whether the function is called by the auto-escaping feature (TRUE) or by
Chris@0:    *   the developer (FALSE).
Chris@0:    *
Chris@0:    * @return string|null
Chris@0:    *   The escaped, rendered output, or NULL if there is no valid output.
Chris@0:    *
Chris@0:    * @throws \Exception
Chris@0:    *   When $arg is passed as an object which does not implement __toString(),
Chris@0:    *   RenderableInterface or toString().
Chris@0:    *
Chris@0:    * @todo Refactor this to keep it in sync with theme_render_and_autoescape()
Chris@0:    *   in https://www.drupal.org/node/2575065
Chris@0:    */
Chris@0:   public function escapeFilter(\Twig_Environment $env, $arg, $strategy = 'html', $charset = NULL, $autoescape = FALSE) {
Chris@0:     // Check for a numeric zero int or float.
Chris@0:     if ($arg === 0 || $arg === 0.0) {
Chris@0:       return 0;
Chris@0:     }
Chris@0: 
Chris@0:     // Return early for NULL and empty arrays.
Chris@0:     if ($arg == NULL) {
Chris@0:       return NULL;
Chris@0:     }
Chris@0: 
Chris@0:     $this->bubbleArgMetadata($arg);
Chris@0: 
Chris@0:     // Keep Twig_Markup objects intact to support autoescaping.
Chris@0:     if ($autoescape && ($arg instanceof \Twig_Markup || $arg instanceof MarkupInterface)) {
Chris@0:       return $arg;
Chris@0:     }
Chris@0: 
Chris@0:     $return = NULL;
Chris@0: 
Chris@0:     if (is_scalar($arg)) {
Chris@0:       $return = (string) $arg;
Chris@0:     }
Chris@0:     elseif (is_object($arg)) {
Chris@0:       if ($arg instanceof RenderableInterface) {
Chris@0:         $arg = $arg->toRenderable();
Chris@0:       }
Chris@0:       elseif (method_exists($arg, '__toString')) {
Chris@0:         $return = (string) $arg;
Chris@0:       }
Chris@0:       // You can't throw exceptions in the magic PHP __toString() methods, see
Chris@0:       // http://php.net/manual/language.oop5.magic.php#object.tostring so
Chris@0:       // we also support a toString method.
Chris@0:       elseif (method_exists($arg, 'toString')) {
Chris@0:         $return = $arg->toString();
Chris@0:       }
Chris@0:       else {
Chris@0:         throw new \Exception('Object of type ' . get_class($arg) . ' cannot be printed.');
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     // We have a string or an object converted to a string: Autoescape it!
Chris@0:     if (isset($return)) {
Chris@0:       if ($autoescape && $return instanceof MarkupInterface) {
Chris@0:         return $return;
Chris@0:       }
Chris@0:       // Drupal only supports the HTML escaping strategy, so provide a
Chris@0:       // fallback for other strategies.
Chris@0:       if ($strategy == 'html') {
Chris@0:         return Html::escape($return);
Chris@0:       }
Chris@0:       return twig_escape_filter($env, $return, $strategy, $charset, $autoescape);
Chris@0:     }
Chris@0: 
Chris@0:     // This is a normal render array, which is safe by definition, with
Chris@0:     // special simple cases already handled.
Chris@0: 
Chris@0:     // Early return if this element was pre-rendered (no need to re-render).
Chris@0:     if (isset($arg['#printed']) && $arg['#printed'] == TRUE && isset($arg['#markup']) && strlen($arg['#markup']) > 0) {
Chris@0:       return $arg['#markup'];
Chris@0:     }
Chris@0:     $arg['#printed'] = FALSE;
Chris@0:     return $this->renderer->render($arg);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Bubbles Twig template argument's cacheability & attachment metadata.
Chris@0:    *
Chris@0:    * For example: a generated link or generated URL object is passed as a Twig
Chris@0:    * template argument, and its bubbleable metadata must be bubbled.
Chris@0:    *
Chris@0:    * @see \Drupal\Core\GeneratedLink
Chris@0:    * @see \Drupal\Core\GeneratedUrl
Chris@0:    *
Chris@0:    * @param mixed $arg
Chris@0:    *   A Twig template argument that is about to be printed.
Chris@0:    *
Chris@0:    * @see \Drupal\Core\Theme\ThemeManager::render()
Chris@0:    * @see \Drupal\Core\Render\RendererInterface::render()
Chris@0:    */
Chris@0:   protected function bubbleArgMetadata($arg) {
Chris@0:     // If it's a renderable, then it'll be up to the generated render array it
Chris@0:     // returns to contain the necessary cacheability & attachment metadata. If
Chris@0:     // it doesn't implement CacheableDependencyInterface or AttachmentsInterface
Chris@0:     // then there is nothing to do here.
Chris@0:     if ($arg instanceof RenderableInterface || !($arg instanceof CacheableDependencyInterface || $arg instanceof AttachmentsInterface)) {
Chris@0:       return;
Chris@0:     }
Chris@0: 
Chris@0:     $arg_bubbleable = [];
Chris@0:     BubbleableMetadata::createFromObject($arg)
Chris@0:       ->applyTo($arg_bubbleable);
Chris@0: 
Chris@0:     $this->renderer->render($arg_bubbleable);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Wrapper around render() for twig printed output.
Chris@0:    *
Chris@0:    * If an object is passed which does not implement __toString(),
Chris@0:    * RenderableInterface or toString() then an exception is thrown;
Chris@0:    * Other objects are casted to string. However in the case that the
Chris@0:    * object is an instance of a Twig_Markup object it is returned directly
Chris@0:    * to support auto escaping.
Chris@0:    *
Chris@0:    * If an array is passed it is rendered via render() and scalar values are
Chris@0:    * returned directly.
Chris@0:    *
Chris@0:    * @param mixed $arg
Chris@0:    *   String, Object or Render Array.
Chris@0:    *
Chris@0:    * @throws \Exception
Chris@0:    *   When $arg is passed as an object which does not implement __toString(),
Chris@0:    *   RenderableInterface or toString().
Chris@0:    *
Chris@0:    * @return mixed
Chris@0:    *   The rendered output or an Twig_Markup object.
Chris@0:    *
Chris@0:    * @see render
Chris@0:    * @see TwigNodeVisitor
Chris@0:    */
Chris@0:   public function renderVar($arg) {
Chris@0:     // Check for a numeric zero int or float.
Chris@0:     if ($arg === 0 || $arg === 0.0) {
Chris@0:       return 0;
Chris@0:     }
Chris@0: 
Chris@0:     // Return early for NULL and empty arrays.
Chris@0:     if ($arg == NULL) {
Chris@0:       return NULL;
Chris@0:     }
Chris@0: 
Chris@0:     // Optimize for scalars as it is likely they come from the escape filter.
Chris@0:     if (is_scalar($arg)) {
Chris@0:       return $arg;
Chris@0:     }
Chris@0: 
Chris@0:     if (is_object($arg)) {
Chris@0:       $this->bubbleArgMetadata($arg);
Chris@0:       if ($arg instanceof RenderableInterface) {
Chris@0:         $arg = $arg->toRenderable();
Chris@0:       }
Chris@0:       elseif (method_exists($arg, '__toString')) {
Chris@0:         return (string) $arg;
Chris@0:       }
Chris@0:       // You can't throw exceptions in the magic PHP __toString() methods, see
Chris@0:       // http://php.net/manual/language.oop5.magic.php#object.tostring so
Chris@0:       // we also support a toString method.
Chris@0:       elseif (method_exists($arg, 'toString')) {
Chris@0:         return $arg->toString();
Chris@0:       }
Chris@0:       else {
Chris@0:         throw new \Exception('Object of type ' . get_class($arg) . ' cannot be printed.');
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     // This is a render array, with special simple cases already handled.
Chris@0:     // Early return if this element was pre-rendered (no need to re-render).
Chris@0:     if (isset($arg['#printed']) && $arg['#printed'] == TRUE && isset($arg['#markup']) && strlen($arg['#markup']) > 0) {
Chris@0:       return $arg['#markup'];
Chris@0:     }
Chris@0:     $arg['#printed'] = FALSE;
Chris@0:     return $this->renderer->render($arg);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Joins several strings together safely.
Chris@0:    *
Chris@0:    * @param \Twig_Environment $env
Chris@0:    *   A Twig_Environment instance.
Chris@0:    * @param mixed[]|\Traversable|null $value
Chris@0:    *   The pieces to join.
Chris@0:    * @param string $glue
Chris@0:    *   The delimiter with which to join the string. Defaults to an empty string.
Chris@0:    *   This value is expected to be safe for output and user provided data
Chris@0:    *   should never be used as a glue.
Chris@0:    *
Chris@0:    * @return string
Chris@0:    *   The strings joined together.
Chris@0:    */
Chris@0:   public function safeJoin(\Twig_Environment $env, $value, $glue = '') {
Chris@0:     if ($value instanceof \Traversable) {
Chris@0:       $value = iterator_to_array($value, FALSE);
Chris@0:     }
Chris@0: 
Chris@0:     return implode($glue, array_map(function ($item) use ($env) {
Chris@0:       // If $item is not marked safe then it will be escaped.
Chris@0:       return $this->escapeFilter($env, $item, 'html', NULL, TRUE);
Chris@0:     }, (array) $value));
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Creates an Attribute object.
Chris@0:    *
Chris@0:    * @param array $attributes
Chris@0:    *   (optional) An associative array of key-value pairs to be converted to
Chris@0:    *   HTML attributes.
Chris@0:    *
Chris@0:    * @return \Drupal\Core\Template\Attribute
Chris@0:    *   An attributes object that has the given attributes.
Chris@0:    */
Chris@0:   public function createAttribute(array $attributes = []) {
Chris@0:     return new Attribute($attributes);
Chris@0:   }
Chris@0: 
Chris@18:   /**
Chris@18:    * Removes child elements from a copy of the original array.
Chris@18:    *
Chris@18:    * Creates a copy of the renderable array and removes child elements by key
Chris@18:    * specified through filter's arguments. The copy can be printed without these
Chris@18:    * elements. The original renderable array is still available and can be used
Chris@18:    * to print child elements in their entirety in the twig template.
Chris@18:    *
Chris@18:    * @param array|object $element
Chris@18:    *   The parent renderable array to exclude the child items.
Chris@18:    * @param string[] ...
Chris@18:    *   The string keys of $element to prevent printing.
Chris@18:    *
Chris@18:    * @return array
Chris@18:    *   The filtered renderable array.
Chris@18:    */
Chris@18:   public function withoutFilter($element) {
Chris@18:     if ($element instanceof \ArrayAccess) {
Chris@18:       $filtered_element = clone $element;
Chris@18:     }
Chris@18:     else {
Chris@18:       $filtered_element = $element;
Chris@18:     }
Chris@18:     $args = func_get_args();
Chris@18:     unset($args[0]);
Chris@18:     foreach ($args as $arg) {
Chris@18:       if (isset($filtered_element[$arg])) {
Chris@18:         unset($filtered_element[$arg]);
Chris@18:       }
Chris@18:     }
Chris@18:     return $filtered_element;
Chris@18:   }
Chris@18: 
Chris@0: }