Fix SASL mechanism selection bug.

ANONYMOUS was being treated as PLAIN, mechanism was being chosen
purely from supported mechanisms, not those provided by the server.

Broke nested handler methods into top-level methods.

sleekxmpp/clientxmpp.py

@@ -112,6 +112,23 @@ class ClientXMPP(BaseXMPP):
                              self.default_ns,
                              'jabber:iq:roster')),
                          self._handle_roster))
+        self.register_handler(
+                Callback('SASL Success',
+                         MatchXPath(sasl.Success.tag_name()),
+                         self._handle_sasl_success,
+                         instream=True,
+                         once=True))
+        self.register_handler(
+                Callback('SASL Failure',
+                         MatchXPath(sasl.Failure.tag_name()),
+                         self._handle_sasl_fail,
+                         instream=True,
+                         once=True))
+        self.register_handler(
+                Callback('STARTTLS Proceed',
+                        MatchXPath(tls.Proceed.tag_name()),
+                        self._handle_starttls_proceed,
+                        instream=True))
 
         self.register_feature('starttls', self._handle_starttls,
                               restart=True,
@@ -130,7 +147,7 @@ class ClientXMPP(BaseXMPP):
                                      self._handle_sasl_plain,
                                      priority=1)
         self.register_sasl_mechanism('ANONYMOUS',
-                                     self._handle_sasl_plain,
+                                     self._handle_sasl_anonymous,
                                      priority=0)
 
     def connect(self, address=tuple(), reattempt=True, use_tls=True):
@@ -349,22 +366,9 @@ class ClientXMPP(BaseXMPP):
         Arguments:
             features -- The stream:features element.
         """
-
-        def tls_proceed(proceed):
-            """Restart the XML stream when TLS is accepted."""
-            log.debug("Starting TLS")
-            if self.start_tls():
-                self.features.append('starttls')
-                raise RestartStream()
-
         if not self.use_tls:
             return False
         elif self.ssl_support:
-            self.register_handler(
-                    Callback('STARTTLS Proceed',
-                            MatchXPath(tls.Proceed.tag_name()),
-                            tls_proceed,
-                            instream=True))
             self.send(features['starttls'], now=True)
             return True
         else:
@@ -372,6 +376,13 @@ class ClientXMPP(BaseXMPP):
                             " to some servers, and has not been found.")
             return False
 
+    def _handle_starttls_proceed(self, proceed):
+        """Restart the XML stream when TLS is accepted."""
+        log.debug("Starting TLS")
+        if self.start_tls():
+            self.features.append('starttls')
+            raise RestartStream()
+
     def _handle_sasl_auth(self, features):
         """
         Handle authenticating using SASL.
@@ -379,46 +390,32 @@ class ClientXMPP(BaseXMPP):
         Arguments:
             features -- The stream features stanza.
         """
-
-        def sasl_success(stanza):
-            """SASL authentication succeeded. Restart the stream."""
-            self.authenticated = True
-            self.features.append('mechanisms')
-            raise RestartStream()
-
-        def sasl_fail(stanza):
-            """SASL authentication failed. Disconnect and shutdown."""
-            log.info("Authentication failed.")
-            self.event("failed_auth", direct=True)
-            self.disconnect()
-            log.debug("Starting SASL Auth")
-            return True
-
-        self.register_handler(
-                Callback('SASL Success',
-                         MatchXPath(sasl.Success.tag_name()),
-                         sasl_success,
-                         instream=True,
-                         once=True))
-
-        self.register_handler(
-                Callback('SASL Failure',
-                         MatchXPath(sasl.Failure.tag_name()),
-                         sasl_fail,
-                         instream=True,
-                         once=True))
-
         for priority, mech in self._sasl_mechanism_priorities:
-            if mech in self._sasl_mechanism_handlers:
+            if mech in features['mechanisms']:
                 handler = self._sasl_mechanism_handlers[mech]
                 if handler(self):
                     break
         else:
             log.error("No appropriate login method.")
+            self.event("no_auth", direct=True)
             self.disconnect()
 
         return True
 
+    def _handle_sasl_success(self, stanza):
+        """SASL authentication succeeded. Restart the stream."""
+        self.authenticated = True
+        self.features.append('mechanisms')
+        raise RestartStream()
+
+    def _handle_sasl_fail(self, stanza):
+        """SASL authentication failed. Disconnect and shutdown."""
+        log.info("Authentication failed.")
+        self.event("failed_auth", direct=True)
+        self.disconnect()
+        log.debug("Starting SASL Auth")
+        return True
+
     def _handle_sasl_plain(self, xmpp):
         """
         Attempt to authenticate using SASL PLAIN.