def test_serial_server_connect(self): with patch.object(serial, 'Serial') as mock_serial: mock_serial.return_value = "socket" identity = ModbusDeviceIdentification(info={0x00: 'VendorName'}) server = ModbusSerialServer(context=None, identity=identity) self.assertEqual(server.socket, "socket") self.assertEqual(server.control.Identity.VendorName, 'VendorName') server._connect() self.assertEqual(server.socket, "socket") with patch.object(serial, 'Serial') as mock_serial: mock_serial.side_effect = serial.SerialException() server = ModbusSerialServer(None) self.assertEqual(server.socket, None)