Issue #3216397 by tbenice, duaelfr: Allow all preprocess functions to modify...

modules/responsive_bg_image_formatter/src/Plugin/Field/FieldFormatter/ResponsiveBgImageFormatter.php

@@ -8,8 +8,10 @@ use Drupal\bg_image_formatter\Plugin\Field\FieldFormatter\BgImageFormatter;
 use Drupal\Core\Field\FieldItemListInterface;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Render\Markup;
+use Drupal\Core\Theme\Registry;
 use Drupal\Core\Url;
 use Drupal\responsive_image\Entity\ResponsiveImageStyle;
+use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
  * Responsive Background Image formatter.
@@ -22,6 +24,22 @@ use Drupal\responsive_image\Entity\ResponsiveImageStyle;
  */
 class ResponsiveBgImageFormatter extends BgImageFormatter {
 
+  /**
+   * The theme registry service.
+   *
+   * @var \Drupal\Core\Theme\Registry
+   */
+  protected Registry $registry;
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    $instance = parent::create($container, $configuration, $plugin_id, $plugin_definition);
+    $instance->registry = $container->get('theme.registry');
+    return $instance;
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -102,23 +120,32 @@ class ResponsiveBgImageFormatter extends BgImageFormatter {
       static::$selectorIndex[$field_id]++;
 
       $uri = $file->getFileUri();
-      $vars = [
+      $variables = [
         'uri' => $file->getFileUri(),
         'responsive_image_style_id' => $settings['image_style'],
         'width' => 1,
         'height' => 1,
       ];
       if (file_exists($uri)) {
-        [$vars['width'], $vars['height']] = getimagesize($uri);
+        [$variables['width'], $variables['height']] = getimagesize($uri);
+      }
+
+      // Call preprocess functions to let other modules/themes react before
+      // rendering.
+      $info = $this->registry->get();
+      $hook = 'responsive_image__responsive_bg_image_formatter';
+      foreach ($info['responsive_image']['preprocess functions'] as $preprocessor_function) {
+        if (is_callable($preprocessor_function)) {
+          call_user_func_array($preprocessor_function, [&$variables, $hook, $info]);
+        }
       }
-      template_preprocess_responsive_image($vars);
 
-      if (empty($vars['sources'])) {
+      if (empty($variables['sources'])) {
         continue;
       }
 
       // Split each source into multiple rules.
-      foreach (array_reverse($vars['sources']) as $source_i => $source) {
+      foreach (array_reverse($variables['sources']) as $source_i => $source) {
         $attr = $source->toArray();
 
         $srcset = explode(', ', $attr['srcset']);