tor_manager: pass endpoints to txtorcon.connect(), not descriptors

This was breaking any uses of --tor-control-port=: the client would always
fall back to using the default SOCKS port.

src/wormhole/test/test_tor_manager.py

@@ -51,13 +51,17 @@ class Tor(unittest.TestCase):
         reactor = object()
         my_tor = X() # object() didn't like providedBy()
         tcp = "port"
+        ep = object()
         connect_d = defer.Deferred()
         stderr = io.StringIO()
         with mock.patch("wormhole.tor_manager.txtorcon.connect",
                         side_effect=connect_d) as connect:
+            with mock.patch("wormhole.tor_manager.clientFromString",
+                            side_effect=[ep]) as sfs:
                 d = get_tor(reactor, tor_control_port=tcp, stderr=stderr)
+        self.assertEqual(sfs.mock_calls, [mock.call(reactor, tcp)])
         self.assertNoResult(d)
-            self.assertEqual(connect.mock_calls, [mock.call(reactor, tcp)])
+        self.assertEqual(connect.mock_calls, [mock.call(reactor, ep)])
         connect_d.callback(my_tor)
         tor = self.successResultOf(d)
         self.assertIs(tor, my_tor)
@@ -67,13 +71,17 @@ class Tor(unittest.TestCase):
     def test_connect_fails(self):
         reactor = object()
         tcp = "port"
+        ep = object()
         connect_d = defer.Deferred()
         stderr = io.StringIO()
         with mock.patch("wormhole.tor_manager.txtorcon.connect",
                         side_effect=connect_d) as connect:
+            with mock.patch("wormhole.tor_manager.clientFromString",
+                            side_effect=[ep]) as sfs:
                 d = get_tor(reactor, tor_control_port=tcp, stderr=stderr)
+        self.assertEqual(sfs.mock_calls, [mock.call(reactor, tcp)])
         self.assertNoResult(d)
-            self.assertEqual(connect.mock_calls, [mock.call(reactor, tcp)])
+        self.assertEqual(connect.mock_calls, [mock.call(reactor, ep)])
 
         connect_d.errback(ConnectError())
         tor = self.successResultOf(d)

src/wormhole/tor_manager.py

@@ -3,6 +3,7 @@ import sys
 from attr import attrs, attrib
 from zope.interface.declarations import directlyProvides
 from twisted.internet.defer import inlineCallbacks, returnValue
+from twisted.internet.endpoints import clientFromString
 try:
     import txtorcon
 except ImportError:
@@ -86,6 +87,9 @@ def get_tor(reactor, launch_tor=False, tor_control_port=None,
                 # If tor_control_port is None (the default), txtorcon
                 # will look through a list of usual places. If it is set,
                 # it will look only in the place we tell it to.
+                if tor_control_port is not None:
+                    tor_control_port = clientFromString(reactor,
+                                                        tor_control_port)
                 tor = yield txtorcon.connect(reactor, tor_control_port)
                 print(" using Tor via control port", file=stderr)
             except Exception: