Issue #3129302 by mradcliffe, jkevingz, deffrin, mxmilkiib, larowlan: Format Default Value

namespace Drupal\date_popup;

use Drupal\Core\Datetime\DrupalDateTime;

use Drupal\datetime\Plugin\Field\FieldType\DateTimeItemInterface;

/**

 * Shared code between the Date and Datetime plugins.

 * Provides shared code between the Date and Datetime plugins.

 */

trait DatePopupTrait {

  /**

   * Apply the HTML5 date popup to the views filter form.

   * Applies the date storage format to default value.

   *

   * @param string $default_value

   *   The date value to be formatted.

   *

   * @param array $form

   * @return string

   *   The formatted value.

   */

  protected function setDefaultValue(string $default_value): string {

    if (!empty($default_value)) {

      $date = new DrupalDateTime($default_value);

      if (!$date->hasErrors()) {

        return $date->format(DateTimeItemInterface::DATE_STORAGE_FORMAT);

      }

    }

    return $default_value;

  }

  /**

   * Applies the HTML5 date popup to the views filter form.

   *

   * @param array &$form

   *   The form to apply it to.

   */

  protected function applyDatePopupToForm(array &$form) {

  protected function applyDatePopupToForm(array &$form): void {

    if (!empty($this->options['expose']['identifier'])) {

      $identifier = $this->options['expose']['identifier'];

      // Identify wrapper.

      if (isset($element['min'])) {

        $element['min']['#type'] = 'date';

        $element['max']['#type'] = 'date';

        if ($this->options['value']['type'] == 'offset') {

          $element['min']['#default_value'] = $this->setDefaultValue($element['min']['#default_value']);

          $element['max']['#default_value'] = $this->setDefaultValue($element['max']['#default_value']);

        }

        if (isset($element['value'])) {

          $element['value']['#type'] = 'date';

        }

      }

      else {

        $element['#type'] = 'date';

        $element['#default_value'] = $this->setDefaultValue($element['#default_value']);

      }

    }

  }