tor: fix TestReconnectSucceed

We now make sure the proxy server is running on a unique port. In
addition, we close the old conn before making a new conn.

tor/controller_test.go

@@ -1,10 +1,12 @@
 package tor
 
 import (
+	"fmt"
 	"net"
 	"net/textproto"
 	"testing"
 
+	"github.com/lightningnetwork/lnd/lntest/port"
 	"github.com/stretchr/testify/require"
 )
 
@@ -116,11 +118,9 @@ func (tp *testProxy) cleanUp() {
 // creates a server and a client connection, and initializes a testProxy using
 // these params.
 func createTestProxy(t *testing.T) *testProxy {
-	// Set up the proxy to listen on given port.
-	//
-	// NOTE: we use a port 0 here to indicate we want a free port selected
-	// by the system.
-	proxy, err := net.Listen("tcp", ":0")
+	// Set up the proxy to listen on a unique port.
+	addr := fmt.Sprintf(":%d", port.NextAvailablePort())
+	proxy, err := net.Listen("tcp", addr)
 	require.NoError(t, err, "failed to create proxy")
 
 	t.Logf("created proxy server to listen on address: %v", proxy.Addr())
@@ -145,6 +145,9 @@ func createTestProxy(t *testing.T) *testProxy {
 		clientConn: client,
 	}
 
+	t.Logf("server listening on %v, client listening on %v",
+		tc.serverConn.LocalAddr(), tc.serverConn.RemoteAddr())
+
 	return tc
 }
 
@@ -309,6 +312,9 @@ func TestReconnectSucceed(t *testing.T) {
 		controlAddr: proxy.serverAddr,
 	}
 
+	// Close the old conn before reconnection.
+	require.NoError(t, proxy.serverConn.Close())
+
 	// Accept the connection inside a goroutine. We will also write some
 	// data so that the reconnection can succeed. We will mock three writes
 	// and two reads inside our proxy server,
@@ -322,6 +328,9 @@ func TestReconnectSucceed(t *testing.T) {
 		server, err := proxy.server.Accept()
 		require.NoError(t, err, "failed to accept")
 
+		t.Logf("server listening on %v, client listening on %v",
+			server.LocalAddr(), server.RemoteAddr())
+
 		// Write the protocol info.
 		resp := "250-PROTOCOLINFO 1\n" +
 			"250-AUTH METHODS=NULL\n" +