Proposed way of creating no-timeout tests and...

... fix for Server.Shutdown() function.

server.go

@@ -304,17 +304,27 @@ func (srv *Server) ActivateAndServe() error {
 // ActivateAndServe will return. All in progress queries are completed before the server
 // is taken down. If the Shutdown was not succesful an error is returned.
 func (srv *Server) Shutdown() error {
-	// TODO(miek): does this work with socket activation? Double check if we set the 
-	// address there. And... is it needed?
-	c := new(Client)
-	c.Net = srv.Net
-	switch srv.Net {
+	// Client sends fake request here to not wait for timeout in readUDP/readTCP loop
+	// and trap to stop event ASAP.
+	net, addr := srv.Net, srv.Addr
+
+	if srv.Listener != nil {
+		a := srv.Listener.Addr()
+		net, addr = a.Network(), a.String()
+	} else if srv.PacketConn != nil {
+		a := srv.PacketConn.LocalAddr()
+		net, addr = a.Network(), a.String()
+	}
+
+	switch net {
 	case "tcp", "tcp4", "tcp6":
 		go func() { srv.stopTCP <- true }()
 	case "udp", "udp4", "udp6":
 		go func() { srv.stopUDP <- true }()
 	}
-	c.Exchange(new(Msg), srv.Addr)
+	c := &Client{Net: net}
+	c.Exchange(new(Msg), addr)
+
 	return nil
 }
 

server_test.go

@@ -31,21 +31,33 @@ func AnotherHelloServer(w ResponseWriter, req *Msg) {
 	w.WriteMsg(m)
 }
 
+func RunLocalUDPServer() (*Server, string, error) {
+	pc, err := net.ListenPacket("udp", "127.0.0.1:0")
+	if err != nil {
+		return nil, "", err
+	}
+	server := &Server{PacketConn: pc}
+	go func() {
+		server.ActivateAndServe()
+		pc.Close()
+	}()
+	return server, pc.LocalAddr().String(), nil
+}
+
 func TestServing(t *testing.T) {
 	HandleFunc("miek.nl.", HelloServer)
 	HandleFunc("example.com.", AnotherHelloServer)
-	go func() {
-		err := ListenAndServe(":8053", "udp", nil)
-		if err != nil {
-			t.Log("ListenAndServe: ", err.Error())
-			t.Fatal()
-		}
-	}()
-	time.Sleep(4e8)
+
+	s, addrstr, err := RunLocalUDPServer()
+	if err != nil {
+		t.Fatalf("Unable to run test server on port 8053: %s", err)
+	}
+	defer s.Shutdown()
+
 	c := new(Client)
 	m := new(Msg)
 	m.SetQuestion("miek.nl.", TypeTXT)
-	r, _, err := c.Exchange(m, "127.0.0.1:8053")
+	r, _, err := c.Exchange(m, addrstr)
 	if err != nil {
 		t.Log("failed to exchange miek.nl", err)
 		t.Fatal()
@@ -57,7 +69,7 @@ func TestServing(t *testing.T) {
 	}
 
 	m.SetQuestion("example.com.", TypeTXT)
-	r, _, err = c.Exchange(m, "127.0.0.1:8053")
+	r, _, err = c.Exchange(m, addrstr)
 	if err != nil {
 		t.Log("failed to exchange example.com", err)
 		t.Fatal()
@@ -70,7 +82,7 @@ func TestServing(t *testing.T) {
 
 	// Test Mixes cased as noticed by Ask.
 	m.SetQuestion("eXaMplE.cOm.", TypeTXT)
-	r, _, err = c.Exchange(m, "127.0.0.1:8053")
+	r, _, err = c.Exchange(m, addrstr)
 	if err != nil {
 		t.Log("failed to exchange eXaMplE.cOm", err)
 		t.Fail()