When a connection is closed, it's not connecting anymore.

No kidding !
And there was a test for this. Muhaha.

neo/lib/connection.py

@@ -506,6 +506,7 @@ class Connection(BaseConnection):
         self._handlers.clear()
         if self.connecting:
             handler.connectionFailed(self)
+            self.connecting = False
         else:
             handler.connectionClosed(self)
 

neo/tests/testConnection.py

@@ -731,7 +731,7 @@ class ConnectionTests(NeoUnitTestBase):
         self._checkConnectionCompleted(1)
         self._checkReaderAdded(1)
         bc.writable()
-        self.assertTrue(bc.connecting)
+        self.assertFalse(bc.connecting)
         self.assertFalse(bc.pending())
         self.assertFalse(bc.aborted)
         self._checkWriteBuf(bc, '')