audio: return self from Interface.load()

amodem/audio.py

@@ -17,6 +17,7 @@ class Interface(object):
         assert self._error_string(0) == b'Success'
         version = self.call('GetVersionText', restype=ctypes.c_char_p)
         log.info('%s loaded', version)
+        return self
 
     def _error_string(self, code):
         return self.call('GetErrorText', code, restype=ctypes.c_char_p)

tests/test_audio.py

@@ -15,7 +15,7 @@ def test():
         lib.Pa_OpenStream.return_value = 0
         cdll.return_value = lib
         interface = audio.Interface(config=config.fastest(), debug=True)
-        interface.load(name='portaudio')
+        assert interface.load(name='portaudio') is interface
         with interface:
             s = interface.player()
             assert s.params.device == 1