theme.inc 67 KB
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<?php
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/**
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 * @file
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 * The theme system, which controls the output of Drupal.
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 *
 * The theme system allows for nearly all output of the Drupal system to be
 * customized by user themes.
 */
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use Drupal\Component\Serialization\Json;
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use Drupal\Component\Utility\Crypt;
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use Drupal\Component\Utility\Html;
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use Drupal\Component\Render\MarkupInterface;
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use Drupal\Core\Cache\CacheableDependencyInterface;
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use Drupal\Core\Config\Config;
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use Drupal\Core\Config\StorageException;
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use Drupal\Core\Render\AttachmentsInterface;
use Drupal\Core\Render\BubbleableMetadata;
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use Drupal\Core\Render\RenderableInterface;
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use Drupal\Core\Template\Attribute;
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use Drupal\Core\Theme\ThemeSettings;
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use Drupal\Component\Utility\NestedArray;
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use Drupal\Core\Render\Element;
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use Drupal\Core\Render\Markup;
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/**
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 * @defgroup content_flags Content markers
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 * @{
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 * Markers used by mark.html.twig and node_mark() to designate content.
 *
 * @see mark.html.twig
 * @see node_mark()
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 */
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/**
 * Mark content as read.
 */
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const MARK_READ = 0;
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/**
 * Mark content as being new.
 */
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const MARK_NEW = 1;
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/**
 * Mark content as being updated.
 */
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const MARK_UPDATED = 2;
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/**
 * A responsive table class; hide table cell on narrow devices.
 *
 * Indicates that a column has medium priority and thus can be hidden on narrow
 * width devices and shown on medium+ width devices (i.e. tablets and desktops).
 */
const RESPONSIVE_PRIORITY_MEDIUM = 'priority-medium';

/**
 * A responsive table class; only show table cell on wide devices.
 *
 * Indicates that a column has low priority and thus can be hidden on narrow
 * and medium viewports and shown on wide devices (i.e. desktops).
 */
const RESPONSIVE_PRIORITY_LOW = 'priority-low';

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/**
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 * @} End of "defgroup content_flags".
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 */

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/**
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 * Gets the theme registry.
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 *
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 * @param bool $complete
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 *   Optional boolean to indicate whether to return the complete theme registry
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 *   array or an instance of the Drupal\Core\Utility\ThemeRegistry class.
 *   If TRUE, the complete theme registry array will be returned. This is useful
 *   if you want to foreach over the whole registry, use array_* functions or
 *   inspect it in a debugger. If FALSE, an instance of the
 *   Drupal\Core\Utility\ThemeRegistry class will be returned, this provides an
 *   ArrayObject which allows it to be accessed with array syntax and isset(),
 *   and should be more lightweight than the full registry. Defaults to TRUE.
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 *
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 * @return
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 *   The complete theme registry array, or an instance of the
 *   Drupal\Core\Utility\ThemeRegistry class.
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 */
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function theme_get_registry($complete = TRUE) {
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  $theme_registry = \Drupal::service('theme.registry');
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  if ($complete) {
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    return $theme_registry->get();
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  }
  else {
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    return $theme_registry->getRuntime();
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  }
}

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/**
 * Returns an array of default theme features.
 *
 * @see \Drupal\Core\Extension\ThemeHandler::$defaultFeatures
 */
function _system_default_theme_features() {
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  return [
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    'favicon',
    'logo',
    'node_user_picture',
    'comment_user_picture',
    'comment_user_verification',
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  ];
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}

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/**
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 * Forces the system to rebuild the theme registry.
 *
 * This function should be called when modules are added to the system, or when
 * a dynamic system needs to add more theme hooks.
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 */
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function drupal_theme_rebuild() {
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  \Drupal::service('theme.registry')->reset();
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}

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/**
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 * Allows themes and/or theme engines to discover overridden theme functions.
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 *
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 * @param array $cache
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 *   The existing cache of theme hooks to test against.
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 * @param array $prefixes
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 *   An array of prefixes to test, in reverse order of importance.
 *
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 * @return array
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 *   The functions found, suitable for returning from hook_theme;
 */
function drupal_find_theme_functions($cache, $prefixes) {
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  $implementations = [];
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  $grouped_functions = \Drupal::service('theme.registry')->getPrefixGroupedUserFunctions($prefixes);
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  foreach ($cache as $hook => $info) {
    foreach ($prefixes as $prefix) {
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      // Find theme functions that implement possible "suggestion" variants of
      // registered theme hooks and add those as new registered theme hooks.
      // The 'pattern' key defines a common prefix that all suggestions must
      // start with. The default is the name of the hook followed by '__'. An
      // 'base hook' key is added to each entry made for a found suggestion,
      // so that common functionality can be implemented for all suggestions of
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      // the same base hook. To keep things simple, deep hierarchy of
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      // suggestions is not supported: each suggestion's 'base hook' key
      // refers to a base hook, not to another suggestion, and all suggestions
      // are found using the base hook's pattern, not a pattern from an
      // intermediary suggestion.
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      $pattern = isset($info['pattern']) ? $info['pattern'] : ($hook . '__');
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      // Grep only the functions which are within the prefix group.
      list($first_prefix,) = explode('_', $prefix, 2);
      if (!isset($info['base hook']) && !empty($pattern) && isset($grouped_functions[$first_prefix])) {
        $matches = preg_grep('/^' . $prefix . '_' . $pattern . '/', $grouped_functions[$first_prefix]);
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        if ($matches) {
          foreach ($matches as $match) {
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            $new_hook = substr($match, strlen($prefix) + 1);
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            $arg_name = isset($info['variables']) ? 'variables' : 'render element';
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            $implementations[$new_hook] = [
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              'function' => $match,
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              $arg_name => $info[$arg_name],
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              'base hook' => $hook,
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            ];
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          }
        }
      }
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      // Find theme functions that implement registered theme hooks and include
      // that in what is returned so that the registry knows that the theme has
      // this implementation.
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      if (function_exists($prefix . '_' . $hook)) {
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        $implementations[$hook] = [
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          'function' => $prefix . '_' . $hook,
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        ];
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      }
    }
  }

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  return $implementations;
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}

/**
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 * Allows themes and/or theme engines to easily discover overridden templates.
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 *
 * @param $cache
 *   The existing cache of theme hooks to test against.
 * @param $extension
 *   The extension that these templates will have.
 * @param $path
 *   The path to search.
 */
function drupal_find_theme_templates($cache, $extension, $path) {
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  $implementations = [];
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  // Collect paths to all sub-themes grouped by base themes. These will be
  // used for filtering. This allows base themes to have sub-themes in its
  // folder hierarchy without affecting the base themes template discovery.
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  $theme_paths = [];
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  foreach (\Drupal::service('theme_handler')->listInfo() as $theme_info) {
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    if (!empty($theme_info->base_theme)) {
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      $theme_paths[$theme_info->base_theme][$theme_info->getName()] = $theme_info->getPath();
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    }
  }
  foreach ($theme_paths as $basetheme => $subthemes) {
    foreach ($subthemes as $subtheme => $subtheme_path) {
      if (isset($theme_paths[$subtheme])) {
        $theme_paths[$basetheme] = array_merge($theme_paths[$basetheme], $theme_paths[$subtheme]);
      }
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    }
  }
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  $theme = \Drupal::theme()->getActiveTheme()->getName();
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  $subtheme_paths = isset($theme_paths[$theme]) ? $theme_paths[$theme] : [];
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  // Escape the periods in the extension.
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  $regex = '/' . str_replace('.', '\.', $extension) . '$/';
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  // Get a listing of all template files in the path to search.
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  $files = file_scan_directory($path, $regex, ['key' => 'filename']);
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  // Find templates that implement registered theme hooks and include that in
  // what is returned so that the registry knows that the theme has this
  // implementation.
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  foreach ($files as $template => $file) {
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    // Ignore sub-theme templates for the current theme.
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    if (strpos($file->uri, str_replace($subtheme_paths, '', $file->uri)) !== 0) {
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      continue;
    }
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    // Remove the extension from the filename.
    $template = str_replace($extension, '', $template);
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    // Transform - in filenames to _ to match function naming scheme
    // for the purposes of searching.
    $hook = strtr($template, '-', '_');
    if (isset($cache[$hook])) {
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      $implementations[$hook] = [
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        'template' => $template,
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        'path' => dirname($file->uri),
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      ];
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    }
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    // Match templates based on the 'template' filename.
    foreach ($cache as $hook => $info) {
      if (isset($info['template'])) {
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        if ($template === $info['template']) {
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          $implementations[$hook] = [
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            'template' => $template,
            'path' => dirname($file->uri),
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          ];
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        }
      }
    }
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  }

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  // Find templates that implement possible "suggestion" variants of registered
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  // theme hooks and add those as new registered theme hooks. See
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  // drupal_find_theme_functions() for more information about suggestions and
  // the use of 'pattern' and 'base hook'.
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  $patterns = array_keys($files);
  foreach ($cache as $hook => $info) {
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    $pattern = isset($info['pattern']) ? $info['pattern'] : ($hook . '__');
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    if (!isset($info['base hook']) && !empty($pattern)) {
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      // Transform _ in pattern to - to match file naming scheme
      // for the purposes of searching.
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      $pattern = strtr($pattern, '_', '-');
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      $matches = preg_grep('/^' . $pattern . '/', $patterns);
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      if ($matches) {
        foreach ($matches as $match) {
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          $file = $match;
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          // Remove the extension from the filename.
          $file = str_replace($extension, '', $file);
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          // Put the underscores back in for the hook name and register this
          // pattern.
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          $arg_name = isset($info['variables']) ? 'variables' : 'render element';
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          $implementations[strtr($file, '-', '_')] = [
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            'template' => $file,
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            'path' => dirname($files[$match]->uri),
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            $arg_name => $info[$arg_name],
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            'base hook' => $hook,
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          ];
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        }
      }
    }
  }
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  return $implementations;
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}

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/**
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 * Retrieves a setting for the current theme or for a given theme.
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 *
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 * The final setting is obtained from the last value found in the following
 * sources:
 * - the saved values from the global theme settings form
 * - the saved values from the theme's settings form
 * To only retrieve the default global theme setting, an empty string should be
 * given for $theme.
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 *
 * @param $setting_name
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 *   The name of the setting to be retrieved.
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 * @param $theme
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 *   The name of a given theme; defaults to the current theme.
 *
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 * @return
 *   The value of the requested setting, NULL if the setting does not exist.
 */
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function theme_get_setting($setting_name, $theme = NULL) {
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  /** @var \Drupal\Core\Theme\ThemeSettings[] $cache */
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  $cache = &drupal_static(__FUNCTION__, []);
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  // If no key is given, use the current theme if we can determine it.
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  if (!isset($theme)) {
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    $theme = \Drupal::theme()->getActiveTheme()->getName();
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  }
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  if (empty($cache[$theme])) {
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    // Create a theme settings object.
    $cache[$theme] = new ThemeSettings($theme);
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    // Get the global settings from configuration.
    $cache[$theme]->setData(\Drupal::config('system.theme.global')->get());
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    // Get the values for the theme-specific settings from the .info.yml files
    // of the theme and all its base themes.
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    $themes = \Drupal::service('theme_handler')->listInfo();
    if (isset($themes[$theme])) {
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      $theme_object = $themes[$theme];

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      // Retrieve configured theme-specific settings, if any.
      try {
        if ($theme_settings = \Drupal::config($theme . '.settings')->get()) {
          $cache[$theme]->merge($theme_settings);
        }
      }
      catch (StorageException $e) {
      }
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      // If the theme does not support a particular feature, override the global
      // setting and set the value to NULL.
      if (!empty($theme_object->info['features'])) {
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        foreach (_system_default_theme_features() as $feature) {
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          if (!in_array($feature, $theme_object->info['features'])) {
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            $cache[$theme]->set('features.' . $feature, NULL);
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          }
        }
      }

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      // Generate the path to the logo image.
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      if ($cache[$theme]->get('logo.use_default')) {
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        $cache[$theme]->set('logo.url', file_url_transform_relative(file_create_url($theme_object->getPath() . '/logo.svg')));
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      }
      elseif ($logo_path = $cache[$theme]->get('logo.path')) {
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        $cache[$theme]->set('logo.url', file_url_transform_relative(file_create_url($logo_path)));
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      }
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      // Generate the path to the favicon.
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      if ($cache[$theme]->get('features.favicon')) {
        $favicon_path = $cache[$theme]->get('favicon.path');
        if ($cache[$theme]->get('favicon.use_default')) {
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          if (file_exists($favicon = $theme_object->getPath() . '/favicon.ico')) {
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            $cache[$theme]->set('favicon.url', file_url_transform_relative(file_create_url($favicon)));
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          }
          else {
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            $cache[$theme]->set('favicon.url', file_url_transform_relative(file_create_url('core/misc/favicon.ico')));
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          }
        }
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        elseif ($favicon_path) {
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          $cache[$theme]->set('favicon.url', file_url_transform_relative(file_create_url($favicon_path)));
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        }
        else {
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          $cache[$theme]->set('features.favicon', FALSE);
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        }
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      }
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    }
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  }

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  return $cache[$theme]->get($setting_name);
}

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/**
 * Escapes and renders variables for theme functions.
 *
 * This method is used in theme functions to ensure that the result is safe for
 * output inside HTML fragments. This mimics the behavior of the auto-escape
 * functionality in Twig.
 *
 * Note: This function should be kept in sync with
 * \Drupal\Core\Template\TwigExtension::escapeFilter().
 *
 * @param mixed $arg
 *   The string, object, or render array to escape if needed.
 *
 * @return string
 *   The rendered string, safe for use in HTML. The string is not safe when used
 *   as any part of an HTML attribute name or value.
 *
 * @throws \Exception
 *   Thrown when an object is passed in which cannot be printed.
 *
 * @see \Drupal\Core\Template\TwigExtension::escapeFilter()
 *
 * @todo Discuss deprecating this in https://www.drupal.org/node/2575081.
 * @todo Refactor this to keep it in sync with Twig filtering in
 *   https://www.drupal.org/node/2575065
 */
function theme_render_and_autoescape($arg) {
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  // If it's a renderable, then it'll be up to the generated render array it
  // returns to contain the necessary cacheability & attachment metadata. If
  // it doesn't implement CacheableDependencyInterface or AttachmentsInterface
  // then there is nothing to do here.
  if (!($arg instanceof RenderableInterface) && ($arg instanceof CacheableDependencyInterface || $arg instanceof AttachmentsInterface)) {
    $arg_bubbleable = [];
    BubbleableMetadata::createFromObject($arg)
      ->applyTo($arg_bubbleable);
    \Drupal::service('renderer')->render($arg_bubbleable);
  }

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  if ($arg instanceof MarkupInterface) {
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    return (string) $arg;
  }
  $return = NULL;

  if (is_scalar($arg)) {
    $return = (string) $arg;
  }
  elseif (is_object($arg)) {
    if ($arg instanceof RenderableInterface) {
      $arg = $arg->toRenderable();
    }
    elseif (method_exists($arg, '__toString')) {
      $return = (string) $arg;
    }
    // You can't throw exceptions in the magic PHP __toString methods, see
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    // http://php.net/manual/language.oop5.magic.php#object.tostring so
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    // we also support a toString method.
    elseif (method_exists($arg, 'toString')) {
      $return = $arg->toString();
    }
    else {
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      throw new \Exception('Object of type ' . get_class($arg) . ' cannot be printed.');
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    }
  }

  // We have a string or an object converted to a string: Escape it!
  if (isset($return)) {
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    return $return instanceof MarkupInterface ? $return : Html::escape($return);
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  }

  // This is a normal render array, which is safe by definition, with special
  // simple cases already handled.

  // Early return if this element was pre-rendered (no need to re-render).
  if (isset($arg['#printed']) && $arg['#printed'] == TRUE && isset($arg['#markup']) && strlen($arg['#markup']) > 0) {
    return (string) $arg['#markup'];
  }
  $arg['#printed'] = FALSE;
  return (string) \Drupal::service('renderer')->render($arg);
}

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/**
 * Converts theme settings to configuration.
 *
 * @see system_theme_settings_submit()
 *
 * @param array $theme_settings
 *   An array of theme settings from system setting form or a Drupal 7 variable.
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 * @param \Drupal\Core\Config\Config $config
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 *   The configuration object to update.
 *
 * @return
 *   The Config object with updated data.
 */
function theme_settings_convert_to_config(array $theme_settings, Config $config) {
  foreach ($theme_settings as $key => $value) {
    if ($key == 'default_logo') {
      $config->set('logo.use_default', $value);
    }
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    elseif ($key == 'logo_path') {
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      $config->set('logo.path', $value);
    }
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    elseif ($key == 'default_favicon') {
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      $config->set('favicon.use_default', $value);
    }
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    elseif ($key == 'favicon_path') {
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      $config->set('favicon.path', $value);
    }
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    elseif ($key == 'favicon_mimetype') {
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      $config->set('favicon.mimetype', $value);
    }
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    elseif (substr($key, 0, 7) == 'toggle_') {
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      $config->set('features.' . mb_substr($key, 7), $value);
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    }
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    elseif (!in_array($key, ['theme', 'logo_upload'])) {
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      $config->set($key, $value);
    }
  }
  return $config;
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}

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/**
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 * Prepares variables for time templates.
 *
 * Default template: time.html.twig.
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 *
 * @param array $variables
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 *   An associative array possibly containing:
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 *   - attributes['timestamp']:
 *   - timestamp:
 *   - text:
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 */
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function template_preprocess_time(&$variables) {
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  // Format the 'datetime' attribute based on the timestamp.
  // @see http://www.w3.org/TR/html5-author/the-time-element.html#attr-time-datetime
  if (!isset($variables['attributes']['datetime']) && isset($variables['timestamp'])) {
    $variables['attributes']['datetime'] = format_date($variables['timestamp'], 'html_datetime', '', 'UTC');
  }

  // If no text was provided, try to auto-generate it.
  if (!isset($variables['text'])) {
    // Format and use a human-readable version of the timestamp, if any.
    if (isset($variables['timestamp'])) {
      $variables['text'] = format_date($variables['timestamp']);
    }
    // Otherwise, use the literal datetime attribute.
    elseif (isset($variables['attributes']['datetime'])) {
      $variables['text'] = $variables['attributes']['datetime'];
    }
  }
}

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/**
 * Prepares variables for datetime form element templates.
 *
 * The datetime form element serves as a wrapper around the date element type,
 * which creates a date and a time component for a date.
 *
 * Default template: datetime-form.html.twig.
 *
 * @param array $variables
 *   An associative array containing:
 *   - element: An associative array containing the properties of the element.
 *     Properties used: #title, #value, #options, #description, #required,
 *     #attributes.
 *
 * @see form_process_datetime()
 */
function template_preprocess_datetime_form(&$variables) {
  $element = $variables['element'];

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  $variables['attributes'] = [];
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  if (isset($element['#id'])) {
    $variables['attributes']['id'] = $element['#id'];
  }
  if (!empty($element['#attributes']['class'])) {
    $variables['attributes']['class'] = (array) $element['#attributes']['class'];
  }

  $variables['content'] = $element;
}

/**
 * Prepares variables for datetime form wrapper templates.
 *
 * Default template: datetime-wrapper.html.twig.
 *
 * @param array $variables
 *   An associative array containing:
 *   - element: An associative array containing the properties of the element.
 *     Properties used: #title, #children, #required, #attributes.
 */
function template_preprocess_datetime_wrapper(&$variables) {
  $element = $variables['element'];

  if (!empty($element['#title'])) {
    $variables['title'] = $element['#title'];
  }

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  // Suppress error messages.
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  $variables['errors'] = NULL;

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  $variables['description'] = NULL;
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  if (!empty($element['#description'])) {
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    $description_attributes = [];
    if (!empty($element['#id'])) {
      $description_attributes['id'] = $element['#id'] . '--description';
    }
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    $variables['description'] = $element['#description'];
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    $variables['description_attributes'] = new Attribute($description_attributes);
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  }

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  $variables['required'] = FALSE;
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  // For required datetime fields 'form-required' & 'js-form-required' classes
  // are appended to the label attributes.
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  if (!empty($element['#required'])) {
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    $variables['required'] = TRUE;
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  }
  $variables['content'] = $element['#children'];
}

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/**
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 * Prepares variables for links templates.
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 *
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 * Default template: links.html.twig.
 *
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 * Unfortunately links templates duplicate the "active" class handling of l()
 * and LinkGenerator::generate() because it needs to be able to set the "active"
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 * class not on the links themselves (<a> tags), but on the list items (<li>
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 * tags) that contain the links. This is necessary for CSS to be able to style
 * list items differently when the link is active, since CSS does not yet allow
 * one to style list items only if it contains a certain element with a certain
 * class. I.e. we cannot yet convert this jQuery selector to a CSS selector:
 * jQuery('li:has("a.is-active")')
 *
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 * @param array $variables
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 *   An associative array containing:
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 *   - links: An array of links to be themed. Each link should be itself an
 *     array, with the following elements:
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 *     - title: The link text.
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 *     - url: (optional) The \Drupal\Core\Url object to link to. If omitted, no
 *       anchor tag is printed out.
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 *     - attributes: (optional) Attributes for the anchor, or for the <span>
 *       tag used in its place if no 'href' is supplied. If element 'class' is
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 *       included, it must be an array of one or more class names.
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 *     If the 'href' element is supplied, the entire link array is passed to
 *     l() as its $options parameter.
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 *   - attributes: A keyed array of attributes for the <ul> containing the list
 *     of links.
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 *   - set_active_class: (optional) Whether each link should compare the
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 *     route_name + route_parameters or href (path), language and query options
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 *     to the current URL, to determine whether the link is "active". If so, an
 *     "active" class will be applied to the list item containing the link, as
 *     well as the link itself. It is important to use this sparingly since it
 *     is usually unnecessary and requires extra processing.
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 *     For anonymous users, the "active" class will be calculated on the server,
 *     because most sites serve each anonymous user the same cached page anyway.
 *     For authenticated users, the "active" class will be calculated on the
 *     client (through JavaScript), only data- attributes are added to list
 *     items and contained links, to prevent breaking the render cache. The
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 *     JavaScript is added in system_page_attachments().
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 *   - heading: (optional) A heading to precede the links. May be an
 *     associative array or a string. If it's an array, it can have the
 *     following elements:
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 *     - text: The heading text.
 *     - level: The heading level (e.g. 'h2', 'h3').
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 *     - attributes: (optional) An array of the CSS attributes for the heading.
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 *     When using a string it will be used as the text of the heading and the
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 *     level will default to 'h2'. Headings should be used on navigation menus
 *     and any list of links that consistently appears on multiple pages. To
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 *     make the heading invisible use the 'visually-hidden' CSS class. Do not
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 *     use 'display:none', which removes it from screen readers and assistive
 *     technology. Headings allow screen reader and keyboard only users to
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 *     navigate to or skip the links. See
 *     http://juicystudio.com/article/screen-readers-display-none.php and
 *     http://www.w3.org/TR/WCAG-TECHS/H42.html for more information.
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 *
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 * @see \Drupal\Core\Utility\LinkGenerator
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 * @see \Drupal\Core\Utility\LinkGenerator::generate()
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 * @see system_page_attachments()
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 */
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function template_preprocess_links(&$variables) {
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  $links = $variables['links'];
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  $heading = &$variables['heading'];
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  if (!empty($links)) {
    // Prepend the heading to the list, if any.
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    if (!empty($heading)) {
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      // Convert a string heading into an array, using a <h2> tag by default.
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      if (is_string($heading)) {
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        $heading = ['text' => $heading];
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      }
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      // Merge in default array properties into $heading.
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      $heading += [
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        'level' => 'h2',
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        'attributes' => [],
      ];
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      // Convert the attributes array into an Attribute object.
      $heading['attributes'] = new Attribute($heading['attributes']);
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    }

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    $variables['links'] = [];
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    foreach ($links as $key => $link) {
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      $item = [];
      $link += [
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        'ajax' => NULL,
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        'url' => NULL,
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      ];
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      $li_attributes = [];
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      $keys = ['title', 'url'];
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      $link_element = [
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        '#type' => 'link',
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        '#title' => $link['title'],
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        '#options' => array_diff_key($link, array_combine($keys, $keys)),
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        '#url' => $link['url'],
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        '#ajax' => $link['ajax'],
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      ];
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      // Handle links and ensure that the active class is added on the LIs, but
      // only if the 'set_active_class' option is not empty.
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      if (isset($link['url'])) {
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        if (!empty($variables['set_active_class'])) {
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          // Also enable set_active_class for the contained link.
          $link_element['#options']['set_active_class'] = TRUE;
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          if (!empty($link['language'])) {
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            $li_attributes['hreflang'] = $link['language']->getId();
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          }

          // Add a "data-drupal-link-query" attribute to let the
          // drupal.active-link library know the query in a standardized manner.
          if (!empty($link['query'])) {
            $query = $link['query'];
            ksort($query);
            $li_attributes['data-drupal-link-query'] = Json::encode($query);
          }

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          /** @var \Drupal\Core\Url $url */
          $url = $link['url'];
          if ($url->isRouted()) {
            // Add a "data-drupal-link-system-path" attribute to let the
            // drupal.active-link library know the path in a standardized manner.
            $system_path = $url->getInternalPath();
            // @todo System path is deprecated - use the route name and parameters.
            // Special case for the front page.
            $li_attributes['data-drupal-link-system-path'] = $system_path == '' ? '<front>' : $system_path;
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          }
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        }
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        $item['link'] = $link_element;
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      }
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      // Handle title-only text items.
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      $item['text'] = $link['title'];
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      if (isset($link['attributes'])) {
        $item['text_attributes'] = new Attribute($link['attributes']);
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      }
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      // Handle list item attributes.
      $item['attributes'] = new Attribute($li_attributes);
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      // Add the item to the list of links.
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      $variables['links'][$key] = $item;
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    }
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  }
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}
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/**
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 * Prepares variables for image templates.
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 *
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 * Default template: image.html.twig.
 *
 * @param array $variables
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 *   An associative array containing:
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 *   - uri: Either the path of the image file (relative to base_path()) or a
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 *     full URL.
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 *   - width: The width of the image (if known).
 *   - height: The height of the image (if known).
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 *   - alt: The alternative text for text-based browsers. HTML 4 and XHTML 1.0
 *     always require an alt attribute. The HTML 5 draft allows the alt
 *     attribute to be omitted in some cases. Therefore, this variable defaults
 *     to an empty string, but can be set to NULL for the attribute to be
 *     omitted. Usually, neither omission nor an empty string satisfies
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 *     accessibility requirements, so it is strongly encouraged for code
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 *     building variables for image.html.twig templates to pass a meaningful
 *     value for this variable.
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 *     - http://www.w3.org/TR/REC-html40/struct/objects.html#h-13.8
 *     - http://www.w3.org/TR/xhtml1/dtds.html
 *     - http://dev.w3.org/html5/spec/Overview.html#alt
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 *   - title: The title text is displayed when the image is hovered in some
 *     popular browsers.
 *   - attributes: Associative array of attributes to be placed in the img tag.
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 *   - srcset: Array of multiple URIs and sizes/multipliers.
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 *   - sizes: The sizes attribute for viewport-based selection of images.
 *     - http://www.whatwg.org/specs/web-apps/current-work/multipage/embedded-content.html#introduction-3:viewport-based-selection-2
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 */
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function template_preprocess_image(&$variables) {
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  if (!empty($variables['uri'])) {
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    $variables['attributes']['src'] = file_url_transform_relative(file_create_url($variables['uri']));
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  }
  // Generate a srcset attribute conforming to the spec at
  // http://www.w3.org/html/wg/drafts/html/master/embedded-content.html#attr-img-srcset
  if (!empty($variables['srcset'])) {
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    $srcset = [];
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    foreach ($variables['srcset'] as $src) {
      // URI is mandatory.
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      $source = file_url_transform_relative(file_create_url($src['uri']));
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      if (isset($src['width']) && !empty($src['width'])) {
        $source .= ' ' . $src['width'];
      }
      elseif (isset($src['multiplier']) && !empty($src['multiplier'])) {
        $source .= ' ' . $src['multiplier'];
      }
      $srcset[] = $source;
    }
    $variables['attributes']['srcset'] = implode(', ', $srcset);
  }
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  foreach (['width', 'height', 'alt', 'title', 'sizes'] as $key) {
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    if (isset($variables[$key])) {
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      // If the property has already been defined in the attributes,
      // do not override, including NULL.
      if (array_key_exists($key, $variables['attributes'])) {
        continue;
      }
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      $variables['attributes'][$key] = $variables[$key];
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    }
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  }
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}
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806

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/**
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 * Prepares variables for table templates.
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 *
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 * Default template: table.html.twig.
 *
 * @param array $variables
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 *   An associative array containing:
 *   - header: An array containing the table headers. Each element of the array
 *     can be either a localized string or an associative array with the
 *     following keys:
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 *     - data: The localized title of the table column, as a string or render
 *       array.
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 *     - field: The database field represented in the table column (required
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 *       if user is to be able to sort on this column).
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 *     - sort: A default sort order for this column ("asc" or "desc"). Only
 *       one column should be given a default sort order because table sorting
 *       only applies to one column at a time.
 *     - class: An array of values for the 'class' attribute. In particular,
 *       the least important columns that can be hidden on narrow and medium
 *       width screens should have a 'priority-low' class, referenced with the
 *       RESPONSIVE_PRIORITY_LOW constant. Columns that should be shown on
 *       medium+ wide screens should be marked up with a class of
 *       'priority-medium', referenced by with the RESPONSIVE_PRIORITY_MEDIUM
 *       constant. Themes may hide columns with one of these two classes on
 *       narrow viewports to save horizontal space.
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 *     - Any HTML attributes, such as "colspan", to apply to the column header
 *       cell.
 *   - rows: An array of table rows. Every row is an array of cells, or an
 *     associative array with the following keys:
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 *     - data: An array of cells.
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 *     - Any HTML attributes, such as "class", to apply to the table row.
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 *     - no_striping: A Boolean indicating that the row should receive no
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 *       'even / odd' styling. Defaults to FALSE.
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 *     Each cell can be either a string or an associative array with the
 *     following keys:
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 *     - data: The string or render array to display in the table cell.
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 *     - header: Indicates this cell is a header.
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 *     - Any HTML attributes, such as "colspan", to apply to the table cell.
 *     Here's an example for $rows:
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 *     @code
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 *     $rows = array(
 *       // Simple row
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 *       array(
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 *         'Cell 1', 'Cell 2', 'Cell 3'
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 *       ),
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 *       // Row with attributes on the row and some of its cells.
 *       array(
 *         'data' => array('Cell 1', array('data' => 'Cell 2', 'colspan' => 2)), 'class' => array('funky')
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 *       ),
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 *     );
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 *     @endcode
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 *   - footer: An array of table rows which will be printed within a <tfoot>
 *     tag, in the same format as the rows element (see above).
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 *   - attributes: An array of HTML attributes to apply to the table tag.
 *   - caption: A localized string to use for the <caption> tag.
 *   - colgroups: An array of column groups. Each element of the array can be
 *     either:
 *     - An array of columns, each of which is an associative array of HTML
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 *       attributes applied to the <col> element.
 *     - An array of attributes applied to the <colgroup> element, which must
 *       include a "data" attribute. To add attributes to <col> elements,
 *       set the "data" attribute with an array of columns, each of which is an
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 *       associative array of HTML attributes.
 *     Here's an example for $colgroup:
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 *     @code
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 *     $colgroup = array(
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 *       // <colgroup> with one <col> element.
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 *       array(
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 *         array(
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 *           'class' => array('funky'), // Attribute for the <col> element.
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 *         ),
 *       ),
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 *       // <colgroup> with attributes and inner <col> elements.
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 *       array(
 *         'data' => array(
 *           array(
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 *             'class' => array('funky'), // Attribute for the <col> element.
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 *           ),
 *         ),
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 *         'class' => array('jazzy'), // Attribute for the <colgroup> element.
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 *       ),
 *     );
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 *     @endcode
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 *     These optional tags are used to group and set properties on columns
 *     within a table. For example, one may easily group three columns and
 *     apply same background style to all.
 *   - sticky: Use a "sticky" table header.
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 *   - empty: The message to display in an extra row if table does not have any
 *     rows.
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 */
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function template_preprocess_table(&$variables) {
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  // Format the table columns:
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  if (!empty($variables['colgroups'])) {
    foreach ($variables['colgroups'] as &$colgroup) {
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      // Check if we're dealing with a simple or complex column
      if (isset($colgroup['data'])) {
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        $cols = $colgroup['data'];
        unset($colgroup['data']);
        $colgroup_attributes = $colgroup;
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      }
      else {
        $cols = $colgroup;
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        $colgroup_attributes = [];
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      }
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      $colgroup = [];
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      $colgroup['attributes'] = new Attribute($colgroup_attributes);
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      $colgroup['cols'] = [];
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      // Build columns.
      if (is_array($cols) && !empty($cols)) {
        foreach ($cols as $col_key => $col) {
          $colgroup['cols'][$col_key]['attributes'] = new Attribute($col);
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        }
      }
    }
  }

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  // Build an associative array of responsive classes keyed by column.
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  $responsive_classes = [];
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  // Format the table header:
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  $ts = [];
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  $header_columns = 0;
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  if (!empty($variables['header'])) {
    $ts = tablesort_init($variables['header']);

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    // Use a separate index with responsive classes as headers
    // may be associative.
    $responsive_index = -1;
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