Create UnknownPort class, add the 'type' property to Port (#149)

Author: Houston4444

src/jack.py

@@ -1793,7 +1793,7 @@ def _wrap_port_ptr(self, ptr):
         elif porttype == _MIDI:
             cls = OwnMidiPort if self.owns(ptr) else MidiPort
         else:
-            assert False
+            cls = UnknownPort
         return cls(ptr, self)
 
 
@@ -1896,6 +1896,11 @@ def unset_alias(self, alias):
         _check(_lib.jack_port_unset_alias(self._ptr, alias.encode()),
                'Error unsetting port alias')
 
+    @property
+    def type(self):
+        """Name of the JACK port type (read-only)."""
+        return _decode(_lib.jack_port_type(self._ptr))    
+
     @property
     def uuid(self):
         """The UUID of the JACK port."""
@@ -1972,6 +1977,17 @@ class MidiPort(Port):
     is_midi = property(lambda self: True, doc='This is always ``True``.')
 
 
+class UnknownPort(Port):
+    """A JACK port with an unknown type
+    
+    This class is derived from `Port` and has exactly the same
+    attributes and methods.
+    """
+
+    is_audio = property(lambda self: False, doc='This is always ``False``.')
+    is_midi = property(lambda self: False, doc='This is always ``False``.')
+
+
 class OwnPort(Port):
     """A JACK audio port owned by a `Client`.