Chris@0: <?php
Chris@0: 
Chris@0: /**
Chris@0:  * @file
Chris@0:  * Handles integration of Twig templates with the Drupal theme system.
Chris@0:  */
Chris@0: 
Chris@0: use Drupal\Component\Utility\Html;
Chris@0: use Drupal\Core\Render\Markup;
Chris@0: use Drupal\Core\Extension\Extension;
Chris@0: 
Chris@0: /**
Chris@0:  * Implements hook_theme().
Chris@0:  */
Chris@0: function twig_theme($existing, $type, $theme, $path) {
Chris@0:   $templates = drupal_find_theme_functions($existing, [$theme]);
Chris@0:   $templates += drupal_find_theme_templates($existing, '.html.twig', $path);
Chris@0:   return $templates;
Chris@0: }
Chris@0: 
Chris@0: /**
Chris@0:  * Implements hook_extension().
Chris@0:  */
Chris@0: function twig_extension() {
Chris@0:   return '.html.twig';
Chris@0: }
Chris@0: 
Chris@0: /**
Chris@0:  * Includes .theme file from themes.
Chris@0:  *
Chris@0:  * @param \Drupal\Core\Extension\Extension $theme
Chris@0:  *   The theme extension object.
Chris@0:  */
Chris@0: function twig_init(Extension $theme) {
Chris@0:   $theme->load();
Chris@0: }
Chris@0: 
Chris@0: /**
Chris@0:  * Implements hook_render_template().
Chris@0:  *
Chris@0:  * Renders a Twig template.
Chris@0:  *
Chris@0:  * If the Twig debug setting is enabled, HTML comments including the theme hook
Chris@0:  * and template file name suggestions will surround the template markup.
Chris@0:  *
Chris@0:  * @param string $template_file
Chris@0:  *   The file name of the template to render.
Chris@0:  * @param array $variables
Chris@0:  *   A keyed array of variables that will appear in the output.
Chris@0:  *
Chris@0:  * @return string|\Drupal\Component\Render\MarkupInterface
Chris@0:  *   The output generated by the template, plus any debug information.
Chris@0:  */
Chris@0: function twig_render_template($template_file, array $variables) {
Chris@0:   /** @var \Twig_Environment $twig_service */
Chris@0:   $twig_service = \Drupal::service('twig');
Chris@0:   $output = [
Chris@0:     'debug_prefix' => '',
Chris@0:     'debug_info' => '',
Chris@0:     'rendered_markup' => '',
Chris@0:     'debug_suffix' => '',
Chris@0:   ];
Chris@0:   try {
Chris@0:     $output['rendered_markup'] = $twig_service->loadTemplate($template_file)->render($variables);
Chris@0:   }
Chris@0:   catch (\Twig_Error_Runtime $e) {
Chris@0:     // In case there is a previous exception, re-throw the previous exception,
Chris@0:     // so that the original exception is shown, rather than
Chris@0:     // \Twig_Template::displayWithErrorHandling()'s exception.
Chris@0:     $previous_exception = $e->getPrevious();
Chris@0:     if ($previous_exception) {
Chris@0:       throw $previous_exception;
Chris@0:     }
Chris@0:     throw $e;
Chris@0:   }
Chris@0:   if ($twig_service->isDebug()) {
Chris@0:     $output['debug_prefix'] .= "\n\n<!-- THEME DEBUG -->";
Chris@0:     $output['debug_prefix'] .= "\n<!-- THEME HOOK: '" . Html::escape($variables['theme_hook_original']) . "' -->";
Chris@0:     // If there are theme suggestions, reverse the array so more specific
Chris@0:     // suggestions are shown first.
Chris@0:     if (!empty($variables['theme_hook_suggestions'])) {
Chris@0:       $variables['theme_hook_suggestions'] = array_reverse($variables['theme_hook_suggestions']);
Chris@0:     }
Chris@0:     // Add debug output for directly called suggestions like
Chris@0:     // '#theme' => 'comment__node__article'.
Chris@0:     if (strpos($variables['theme_hook_original'], '__') !== FALSE) {
Chris@0:       $derived_suggestions[] = $hook = $variables['theme_hook_original'];
Chris@0:       while ($pos = strrpos($hook, '__')) {
Chris@0:         $hook = substr($hook, 0, $pos);
Chris@0:         $derived_suggestions[] = $hook;
Chris@0:       }
Chris@0:       // Get the value of the base hook (last derived suggestion) and append it
Chris@0:       // to the end of all theme suggestions.
Chris@0:       $base_hook = array_pop($derived_suggestions);
Chris@0:       $variables['theme_hook_suggestions'] = array_merge($derived_suggestions, $variables['theme_hook_suggestions']);
Chris@0:       $variables['theme_hook_suggestions'][] = $base_hook;
Chris@0:     }
Chris@0:     if (!empty($variables['theme_hook_suggestions'])) {
Chris@0:       $extension = twig_extension();
Chris@0:       $current_template = basename($template_file);
Chris@0:       $suggestions = $variables['theme_hook_suggestions'];
Chris@0:       // Only add the original theme hook if it wasn't a directly called
Chris@0:       // suggestion.
Chris@0:       if (strpos($variables['theme_hook_original'], '__') === FALSE) {
Chris@0:         $suggestions[] = $variables['theme_hook_original'];
Chris@0:       }
Chris@0:       foreach ($suggestions as &$suggestion) {
Chris@0:         $template = strtr($suggestion, '_', '-') . $extension;
Chris@0:         $prefix = ($template == $current_template) ? 'x' : '*';
Chris@0:         $suggestion = $prefix . ' ' . $template;
Chris@0:       }
Chris@0:       $output['debug_info'] .= "\n<!-- FILE NAME SUGGESTIONS:\n   " . Html::escape(implode("\n   ", $suggestions)) . "\n-->";
Chris@0:     }
Chris@0:     $output['debug_info']   .= "\n<!-- BEGIN OUTPUT from '" . Html::escape($template_file) . "' -->\n";
Chris@0:     $output['debug_suffix'] .= "\n<!-- END OUTPUT from '" . Html::escape($template_file) . "' -->\n\n";
Chris@0:   }
Chris@0:   // This output has already been rendered and is therefore considered safe.
Chris@0:   return Markup::create(implode('', $output));
Chris@0: }
Chris@0: 
Chris@0: /**
Chris@0:  * Removes child elements from a copy of the original array.
Chris@0:  *
Chris@0:  * Creates a copy of the renderable array and removes child elements by key
Chris@0:  * specified through filter's arguments. The copy can be printed without these
Chris@0:  * elements. The original renderable array is still available and can be used
Chris@0:  * to print child elements in their entirety in the twig template.
Chris@0:  *
Chris@0:  * @param array|object $element
Chris@0:  *   The parent renderable array to exclude the child items.
Chris@0:  * @param string[] ...
Chris@0:  *   The string keys of $element to prevent printing.
Chris@0:  *
Chris@0:  * @return array
Chris@0:  *   The filtered renderable array.
Chris@0:  */
Chris@0: function twig_without($element) {
Chris@0:   if ($element instanceof ArrayAccess) {
Chris@0:     $filtered_element = clone $element;
Chris@0:   }
Chris@0:   else {
Chris@0:     $filtered_element = $element;
Chris@0:   }
Chris@0:   $args = func_get_args();
Chris@0:   unset($args[0]);
Chris@0:   foreach ($args as $arg) {
Chris@0:     if (isset($filtered_element[$arg])) {
Chris@0:       unset($filtered_element[$arg]);
Chris@0:     }
Chris@0:   }
Chris@0:   return $filtered_element;
Chris@0: }