code: public function fillInWithValueOfFieldOfCurrentUser($field, $user_field)
      {
          if (!empty($this->user) && !$this->user->uid) {
              throw new \Exception('Anonymous user have no fields');
          }
  
          $entity = new EntityDrupalWrapper('user');
          $wrapper = $entity->wrapper($this->user->uid);
          $user_field = $entity->getFieldNameByLocator($user_field);
  
          if (empty($wrapper->{$user_field})) {
              throw new \InvalidArgumentException(sprintf('User entity has no "%s" field.', $user_field));
          }
  
          $value = $wrapper->{$user_field}->value();
  
          if (empty($value)) {
              throw new \UnexpectedValueException('The value of "%s" field is empty.', $user_field);
          }
  
          $this->fillField($field, $value);
      }
docs: Use the current user data for filling fields.
  
  @example
  Then I fill "First name" with value of field "First name" of current user
  And fill "field_last_name[und][0]" with value of field "field_user_last_name" of current user
  
  @param string $field
  The name of field to fill in. HTML Label, name or ID can be user as selector.
  @param string $user_field
  The name of field from which the data will taken. Drupal label or machine name can be used as selector.
  
  @throws \InvalidArgumentException
  @throws \UnexpectedValueException
  @throws \Exception
  @throws NoSuchElement
  When field cannot be found.
  
  @Then /^(?:I )fill "([^"]*)" with value of field "([^"]*)" of current user$/