package client
 
 import (
 	"crypto/tls"
 	"errors"
 	"net/http"
 )
 
 var errTLSConfigUnavailable = errors.New("TLSConfig unavailable")
 
 // transportFunc allows us to inject a mock transport for testing. We define it
 // here so we can detect the tlsconfig and return nil for only this type.
 type transportFunc func(*http.Request) (*http.Response, error)
 
 func (tf transportFunc) RoundTrip(req *http.Request) (*http.Response, error) {
 	return tf(req)
 }
 
 // resolveTLSConfig attempts to resolve the tls configuration from the
 // RoundTripper.

 func resolveTLSConfig(transport http.RoundTripper) *tls.Config {

 	switch tr := transport.(type) {
 	case *http.Transport:

 		return tr.TLSClientConfig

 	default:

 		return nil

 	}
 }