protected function normalizeSoapClientOptions(Options $options, array $value)
    {
        // The SOAP_SINGLE_ELEMENT_ARRAYS feature should be enabled by default if no other option has been set
        // explicitly while leaving this out. This cannot be handled in the defaults as soapClientOptions is a
        // nested array.
        if (!isset($value['features'])) {
            $value['features'] = SOAP_SINGLE_ELEMENT_ARRAYS;
        }

        // Merge proxy options into soapClientOptions to propagate general configuration options into the
        // SoapClient. It is important that the proxy configuration has been normalized before it is merged.
        // The OptionResolver ensures this by normalizing values on access.
        if (!empty($options['proxy'])) {
            $value = array_merge($options['proxy'], $value);
        }

        return $value;
    }