Issue #3176391 by cburschka, rahulrasgon: Image links with multiple query...

Issue #3176391 by cburschka, rahulrasgon: Image links with multiple query parameters have ampersand encoded

Closes #3180274

src/Plugin/Field/FieldFormatter/ListExportFormatter.php

+<?php
+
+namespace Drupal\rest_views\Plugin\Field\FieldFormatter;
+
+use Drupal\Core\Field\Annotation\FieldFormatter;
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\FormatterBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Form\OptGroup;
+use Drupal\rest_views\SerializedData;
+
+/**
+ * Export a list.
+ *
+ * @FieldFormatter(
+ *   id = "list_export",
+ *   label = @Translation("Export list"),
+ *   field_types = {
+ *     "list_integer",
+ *     "list_float",
+ *     "list_string",
+ *   }
+ * )
+ */
+class ListExportFormatter extends FormatterBase {
+  const VALUE_LABEL = 'value_label';
+  const KEY_VALUE   = 'key_value';
+  const EXPORT_OPTIONS = [
+    self::VALUE_LABEL => 'Export label and value separately',
+    self::KEY_VALUE   => 'Export as key/value',
+  ];
+
+  /**
+   * {@inheritdoc}
+   */
+  public function viewElements(FieldItemListInterface $items, $langcode): array {
+    $elements = [];
+    $export_format = $this->getSetting('export_format');
+
+    // Only collect allowed options if there are actually items to display.
+    if ($items->count()) {
+      $provider = $items->getFieldDefinition()
+        ->getFieldStorageDefinition()
+        ->getOptionsProvider('value', $items->getEntity());
+      // Flatten the possible options, to support opt groups.
+      $options = OptGroup::flattenOptions($provider->getPossibleOptions());
+
+      foreach ($items as $delta => $item) {
+        $value = $item->value;
+        $label = isset($options[$value]) ? $options[$value]: "";
+        if ($export_format == self::VALUE_LABEL) {
+          $data = [
+            "value" => $value,
+            "label" => $label,
+          ];
+        } else {
+          $data = [$value => $label];
+        }
+        $elements[$delta] = [
+          '#type' => 'data',
+          '#data' => SerializedData::create($data),
+        ];
+      }
+    }
+
+    return $elements;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function defaultSettings(): array {
+    return ['export_format' => self::VALUE_LABEL] + parent::defaultSettings();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function settingsForm(array $form, FormStateInterface $form_state) {
+    $elements = parent::settingsForm($form, $form_state);
+    $elements['export_format'] = [
+      '#type'          => 'radios',
+      '#title'         => $this->t('Export format'),
+      '#default_value' => $this->getSetting('export_format'),
+      '#options'       => array_map([$this, 't'], self::EXPORT_OPTIONS),
+    ];
+    return $elements;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function settingsSummary(): array {
+    $summary = parent::settingsSummary();
+    $export_format = $this->getSetting('export_format');
+    $summary[] = $this->t(self::EXPORT_OPTIONS[$export_format]);
+    return $summary;
+  }
+
+}