code: protected function createConfigurationDefinition()
      {
          $values = ['inside', 'outside'];
  
          return new FixerConfigurationResolverRootless('positions', [
              (new FixerOptionBuilder('positions', 'Whether spacing should be fixed inside and/or outside the offset braces.'))
                  ->setAllowedTypes(['array'])
                  ->setAllowedValues([new AllowedValueSubset($values)])
                  ->setDefault($values)
                  ->getOption(),
          ], $this->getName());
      }
docs: {@inheritdoc}