trait WorkspaceTestTrait in Drupal 8

trait WorkspaceTestTrait {

  /**
   * The workspaces manager.
   *
   * @var \Drupal\workspaces\WorkspaceManagerInterface
   */
  protected $workspaceManager;

  /**
   * An array of test workspaces, keyed by workspace ID.
   *
   * @var \Drupal\workspaces\WorkspaceInterface[]
   */
  protected $workspaces = [];

  /**
   * Enables the Workspaces module and creates two workspaces.
   */
  protected function initializeWorkspacesModule() {

    // Enable the Workspaces module here instead of the static::$modules array
    // so we can test it with default content.
    $this
      ->enableModules([
      'workspaces',
    ]);
    $this->container = \Drupal::getContainer();
    $this->entityTypeManager = \Drupal::entityTypeManager();
    $this->workspaceManager = \Drupal::service('workspaces.manager');
    $this
      ->installEntitySchema('workspace');
    $this
      ->installSchema('workspaces', [
      'workspace_association',
    ]);

    // Create two workspaces by default, 'live' and 'stage'.
    $this->workspaces['live'] = Workspace::create([
      'id' => 'live',
      'label' => 'Live',
    ]);
    $this->workspaces['live']
      ->save();
    $this->workspaces['stage'] = Workspace::create([
      'id' => 'stage',
      'label' => 'Stage',
    ]);
    $this->workspaces['stage']
      ->save();
    $permissions = array_intersect([
      'administer nodes',
      'create workspace',
      'edit any workspace',
      'view any workspace',
    ], array_keys($this->container
      ->get('user.permissions')
      ->getPermissions()));
    $this
      ->setCurrentUser($this
      ->createUser($permissions));
  }

  /**
   * Sets a given workspace as active.
   *
   * @param string $workspace_id
   *   The ID of the workspace to switch to.
   */
  protected function switchToWorkspace($workspace_id) {

    // Switch the test runner's context to the specified workspace.
    $workspace = $this->entityTypeManager
      ->getStorage('workspace')
      ->load($workspace_id);
    \Drupal::service('workspaces.manager')
      ->setActiveWorkspace($workspace);
  }

  /**
   * Creates the following workspace hierarchy:
   * live
   * - stage
   *   - dev
   *     - local_1
   *     - local_2
   * - qa
   */
  protected function createWorkspaceHierarchy() {
    $this->workspaces['dev'] = Workspace::create([
      'id' => 'dev',
      'parent' => 'stage',
    ]);
    $this->workspaces['dev']
      ->save();
    $this->workspaces['local_1'] = Workspace::create([
      'id' => 'local_1',
      'parent' => 'dev',
    ]);
    $this->workspaces['local_1']
      ->save();
    $this->workspaces['local_2'] = Workspace::create([
      'id' => 'local_2',
      'parent' => 'dev',
    ]);
    $this->workspaces['local_2']
      ->save();
    $this->workspaces['qa'] = Workspace::create([
      'id' => 'qa',
      'parent' => 'live',
    ]);
    $this->workspaces['qa']
      ->save();
  }

  /**
   * Checks the workspace_association records for a test scenario.
   *
   * @param array $expected
   *   An array of expected values, as defined in ::testWorkspaces().
   * @param string $entity_type_id
   *   The ID of the entity type that is being tested.
   */
  protected function assertWorkspaceAssociation(array $expected, $entity_type_id) {

    /** @var \Drupal\workspaces\WorkspaceAssociationInterface $workspace_association */
    $workspace_association = \Drupal::service('workspaces.association');
    foreach ($expected as $workspace_id => $expected_tracked_revision_ids) {
      $tracked_entities = $workspace_association
        ->getTrackedEntities($workspace_id, $entity_type_id);
      $tracked_revision_ids = isset($tracked_entities[$entity_type_id]) ? $tracked_entities[$entity_type_id] : [];
      $this
        ->assertEquals($expected_tracked_revision_ids, array_keys($tracked_revision_ids));
    }
  }

  /**
   * Returns all the revisions which are not associated with any workspace.
   *
   * @param string $entity_type_id
   *   An entity type ID to find revisions for.
   * @param int[]|string[]|null $entity_ids
   *   (optional) An array of entity IDs to filter the results by. Defaults to
   *   NULL.
   *
   * @return array
   *   An array of entity IDs, keyed by revision IDs.
   */
  protected function getUnassociatedRevisions($entity_type_id, $entity_ids = NULL) {
    $entity_type = \Drupal::entityTypeManager()
      ->getDefinition($entity_type_id);
    $query = \Drupal::entityTypeManager()
      ->getStorage($entity_type_id)
      ->getQuery()
      ->allRevisions()
      ->accessCheck(FALSE)
      ->notExists($entity_type
      ->get('revision_metadata_keys')['workspace']);
    if ($entity_ids) {
      $query
        ->condition($entity_type
        ->getKey('id'), $entity_ids, 'IN');
    }
    return $query
      ->execute();
  }

}