private static function getGraphqlScalar(string $className, GQL\Scalar $scalarAnnotation, array $classAnnotations)
    {
        $scalarConfiguration = [];

        if ($scalarAnnotation->scalarType) {
            $scalarConfiguration['scalarType'] = self::formatExpression($scalarAnnotation->scalarType);
        } else {
            $scalarConfiguration = [
                'serialize' => [$className, 'serialize'],
                'parseValue' => [$className, 'parseValue'],
                'parseLiteral' => [$className, 'parseLiteral'],
            ];
        }

        $scalarConfiguration = self::getDescriptionConfiguration($classAnnotations) + $scalarConfiguration;

        return ['type' => 'custom-scalar', 'config' => $scalarConfiguration];
    }