private function getDirectiveArgTypeNode(Directive $directive, $argName)
    {
        $argNode = $this->getAllDirectiveArgNodes($directive, $argName)[0];

        return $argNode ? $argNode->type : null;
    }
private function getDirectiveArgTypeNode(Directive $directive, $argName)
    {
        $argNode = $this->getAllDirectiveArgNodes($directive, $argName)[0];

        return $argNode ? $argNode->type : null;
    }
private function getDirectiveArgTypeNode ( Directive $ directive , $ argName ) { $ argNode = $ this -> getAllDirectiveArgNodes ( $ directive , $ argName ) [ 0 ] ; return $ argNode ? $ argNode -> type : null ; }
@param string $argName

@return TypeNode|null
@param string $argName