Fix a reconnecting regression

hybridbot.py

@@ -135,15 +135,22 @@ class XMPPBot:
     def connect(self):
         self.client.connect()
 
-    @asyncio.coroutine
-    def join_muc_loop(self):
-        muc_plugin = self.client.plugin['xep_0045']
-        while not self.muc_is_joined:
-            muc_plugin.join_muc(self.muc, self.nick)
-            yield from asyncio.sleep(self.timeout)
-
     def join_muc(self):
-        asyncio.async(self.join_muc_loop())
+        muc_plugin = self.client.plugin['xep_0045']
+        @asyncio.coroutine
+        def loop_cycle():
+            if self._join_muc_block > 0:
+                return
+            self._join_muc_block += 1
+
+            while not self.muc_is_joined:
+                muc_plugin.join_muc(self.muc, self.nick)
+                yield from asyncio.sleep(self.timeout)
+
+            self._join_muc_block -= 1
+
+        asyncio.async(loop_cycle())
+    _join_muc_block = 0
 
     def on_failed_all_auth(event):
         # print('could not connect!', file=sys.stderr)