class Php

1. 8.x drupal/core/lib/Drupal/Component/Uuid/Php.php \Drupal\Component\Uuid\Php
2. 8.x drupal/core/modules/php/lib/Drupal/php/Plugin/Filter/Php.php \Drupal\php\Plugin\Filter\Php
3. 8.x drupal/core/modules/php/lib/Drupal/php/Plugin/Condition/Php.php \Drupal\php\Plugin\Condition\Php
4. 8.x drupal/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/Php.php \Drupal\views\Plugin\views\argument_validator\Php
5. 8.x drupal/core/modules/views/lib/Drupal/views/Plugin/views/argument_default/Php.php \Drupal\views\Plugin\views\argument_default\Php

class Php extends ArgumentDefaultPluginBase {
  protected function defineOptions() {
    $options = parent::defineOptions();
    $options['code'] = array(
      'default' => '',
    );
    return $options;
  }
  public function buildOptionsForm(&$form, &$form_state) {
    parent::buildOptionsForm($form, $form_state);
    $form['code'] = array(
      '#type' => 'textarea',
      '#title' => t('PHP contextual filter code'),
      '#default_value' => $this->options['code'],
      '#description' => t('Enter PHP code that returns a value to use for this filter. Do not use <?php ?>. You must return only a single value for just this filter. Some variables are available: the view object will be "$view". The argument handler will be "$argument", for example you may change the title used for substitutions for this argument by setting "argument->validated_title"".'),
    );

    // Only do this if using one simple standard form gadget
    $this
      ->checkAccess($form, 'code');
  }

  /**
   * Only let users with PHP block visibility permissions set/modify this
   * default plugin.
   */
  public function access() {
    return user_access('use PHP for settings');
  }
  public function getArgument() {

    // set up variables to make it easier to reference during the argument.
    $view =& $this->view;
    $argument =& $this->argument;
    ob_start();
    $result = eval($this->options['code']);
    ob_end_clean();
    return $result;
  }

}