Test client with TLS support

See #297

client_test.go

@@ -1,6 +1,7 @@
 package dns
 
 import (
+	"crypto/tls"
 	"fmt"
 	"net"
 	"strconv"
@@ -39,6 +40,43 @@ func TestClientSync(t *testing.T) {
 	}
 }
 
+func TestClientTLSSync(t *testing.T) {
+	HandleFunc("miek.nl.", HelloServer)
+	defer HandleRemove("miek.nl.")
+
+	cert, err := tls.X509KeyPair(CertPEMBlock, KeyPEMBlock)
+	if err != nil {
+		t.Fatalf("unable to build certificate: %v", err)
+	}
+
+	config := tls.Config{
+		Certificates: []tls.Certificate{cert},
+	}
+
+	s, addrstr, err := RunLocalTLSServer("127.0.0.1:0", &config)
+	if err != nil {
+		t.Fatalf("unable to run test server: %v", err)
+	}
+	defer s.Shutdown()
+
+	m := new(Msg)
+	m.SetQuestion("miek.nl.", TypeSOA)
+
+	c := new(Client)
+	c.Net = "tcp-tls"
+	c.TLSConfig = &tls.Config{
+		InsecureSkipVerify: true,
+	}
+
+	r, _, err := c.Exchange(m, addrstr)
+	if err != nil {
+		t.Errorf("failed to exchange: %v", err)
+	}
+	if r != nil && r.Rcode != RcodeSuccess {
+		t.Errorf("failed to get an valid answer\n%v", r)
+	}
+}
+
 func TestClientSyncBadId(t *testing.T) {
 	HandleFunc("miek.nl.", HelloServerBadId)
 	defer HandleRemove("miek.nl.")