Issue #3268790 by marcoscano: Skip widgets that don't render multiple values as a table

use Drupal\Core\Form\FormStateInterface;

use Drupal\Core\Render\Element;

/**

 * Widget IDs that can be simplified with the SAM module.

 */

const SAM_ALLOWED_WIDGET_TYPES = [

  'email_default',

  'entity_reference_autocomplete',

  'link_default',

  'number',

  'path',

  'string_textarea',

  'string_textfield',

  'telephone',

  'uri',

];

/**

 * Implements hook_field_widget_multivalue_form_alter().

 */

function sam_field_widget_multivalue_form_alter(array &$elements, FormStateInterface $form_state, array $context) {

  // Affect all multi-value widgets where cardinality is limited and > 1.

  if (!empty($context['items']) && !empty($elements['#cardinality']) && $elements['#cardinality'] > 1) {

    // Skip simplifying this if the widget was configured to show all elements.

    $widget = $context['widget'];

  $widget = $context['widget'] ?? NULL;

  assert($widget instanceof WidgetBaseInterface);

    if ($widget->getThirdPartySetting('sam', 'skip_simplification', FALSE)) {

  $field_definition = $context['items']->getFieldDefinition() ?? NULL;

  assert($field_definition instanceof FieldDefinitionInterface);

  if (empty($widget) || empty($field_definition)) {

    return;

  }

  // Abort early if this is a widget whose markup we can't simplify, or if the

  // field cardinality isn't limited > 1.

  if (sam_skip_widget($widget, $field_definition)) {

    return;

  }

  $items = $context['items'];

    $elements['#attributes']['data-sam-wrapper-simplify'] = TRUE;

  }

}

}

/**

 * Implements hook_preprocess_HOOK() for field_multiple_value_form().

 */

function sam_field_widget_third_party_settings_form(WidgetInterface $plugin, FieldDefinitionInterface $field_definition, $form_mode, array $form, FormStateInterface $form_state) {

  $element = [];

  $cardinality = $field_definition->getFieldStorageDefinition()->getCardinality();

  // @todo Is this too aggressive? We are adding this setting to all widgets,

  // even if they don't display as a table. Maybe it's a good idea to figure

  // that out and only display this checkbox where we can actually simplify.

  if ($cardinality > 1) {

  if (!sam_skip_widget($plugin, $field_definition)) {

    $element['skip_simplification'] = [

      '#type' => 'checkbox',

      '#title' => t('Skip "Simple Add More" simplification (i.e. show all elements, even if empty).'),

  }

  return $element;

}

/**

 * Helper to decide if our code should affect a widget/field.

 *

 * @param \Drupal\Core\Field\WidgetInterface $widget_plugin

 *   The widget plugin instance.

 * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition

 *   The field definition object.

 *

 * @return bool

 *   TRUE (meaning we should skip this field/widget) if:

 *   - The cardinality is not > 1, or

 *   - The widget has been explicitly marked to be skipped in the settings, or

 *   - The widget is not one of the ones we can simplify, due to its markup.

 *   FALSE in all other cases.

 */

function sam_skip_widget(WidgetInterface $widget_plugin, FieldDefinitionInterface $field_definition) {

  $cardinality = $field_definition->getFieldStorageDefinition()->getCardinality();

  if ($cardinality <= 1) {

    return TRUE;

  }

  if ($widget_plugin->getThirdPartySetting('sam', 'skip_simplification', FALSE)) {

    return TRUE;

  }

  // @todo For now the most robust approach is just to explicitly stick to the

  // ones we know we can simplify.

  if (!in_array($widget_plugin->getPluginId(), SAM_ALLOWED_WIDGET_TYPES, TRUE)) {

    return TRUE;

  }

  return FALSE;

}