plugin-8.x-2.8/tests/modules/plugin_test_helper/src/Plugin/PluginTestHelper/MockConfigurablePlugin.php

<?php

namespace Drupal\plugin_test_helper\Plugin\PluginTestHelper;

use Drupal\Component\Plugin\ConfigurableInterface;
use Drupal\Component\Utility\NestedArray;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Plugin\PluginBase;
use Drupal\Core\Plugin\PluginFormInterface;

/**
 * Provides a configurable mock plugin.
 */
class MockConfigurablePlugin extends PluginBase implements ConfigurableInterface, PluginFormInterface, MockPluginInterface {

  /**
   * Constructs a new instance.
   *
   * @param array $configuration
   *   A configuration array containing information about the plugin instance.
   * @param string $plugin_id
   *   The plugin_id for the plugin instance.
   * @param mixed $plugin_definition
   *   The plugin implementation definition.
   */
  public function __construct(array $configuration, $plugin_id, $plugin_definition) {
    parent::__construct($configuration + $this->defaultConfiguration(), $plugin_id, $plugin_definition);
  }

  /**
   * {@inheritdoc}
   */
  public function calculateDependencies() {
    return [];
  }

  /**
   * {@inheritdoc}
   */
  public function getConfiguration() {
    return $this->configuration;
  }

  /**
   * {@inheritdoc}
   */
  public function setConfiguration(array $configuration) {
    $this->configuration = $configuration + $this->defaultConfiguration();
  }

  /**
   * {@inheritdoc}
   */
  public function defaultConfiguration() {
    return [
      'foo' => 'Foo',
    ];
  }

  /**
   * {@inheritdoc}
   */
  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
    $form['foo'] = [
      '#type' => 'textfield',
      '#title' => 'Foo value',
      '#default_value' => $this->configuration['foo'],
    ];

    return $form;
  }

  /**
   * {@inheritdoc}
   */
  public function validateConfigurationForm(array &$form, FormStateInterface $form_state) {
  }

  /**
   * {@inheritdoc}
   */
  public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
    $values = NestedArray::getValue($form_state->getValues(), $form['#parents']);
    $this->configuration['foo'] = $values['foo'];
  }

}