PartKeepr\AuthBundle\Services\UserService::deleteFOSUser PHP Method

    public function deleteFOSUser(User $user)
    {
        if ($user->getProvider()->getType() !== self::BUILTIN_PROVIDER) {
            return;
        }
        $FOSUser = $this->userManager->findUserByUsername($user->getUsername());
        if ($FOSUser !== null) {
            $this->userManager->deleteUser($FOSUser);
        }
    }

 /**
  * Returns an item to delete.
  *
  * @param Request    $request
  * @param string|int $id
  *
  * @return mixed
  *
  * @throws NotFoundHttpException
  * @throws RuntimeException
  * @throws UserProtectedException
  */
 public function __invoke(Request $request, $id)
 {
     list($resourceType) = $this->extractAttributes($request);
     /**
      * @var User $item
      */
     $item = $this->getItem($this->dataProvider, $resourceType, $id);
     if ($item->isProtected()) {
         throw new UserProtectedException();
     }
     $this->userService->deleteFOSUser($item);
     return $item;
 }