tests/tools/conftest.py
author Andrey Skvortsov <andrej.skvortzov@gmail.com>
Fri, 10 Aug 2018 17:45:33 +0300
changeset 2278 a3ac46366b86
parent 1881 091005ec69c4
permissions -rw-r--r--
Dirty fix for error '_object_has_no_attribute_'getSlave' in EtherCAT extension

traceback:
File "/home/developer/WorkData/PLC/beremiz/beremiz/IDEFrame.py", line 1433, in OnPouSelectedChanged
window.RefreshView()
File "/home/developer/WorkData/PLC/beremiz/beremiz/etherlab/ConfigEditor.py", line 837, in RefreshView
self.RefreshProcessVariables()
File "/home/developer/WorkData/PLC/beremiz/beremiz/etherlab/ConfigEditor.py", line 886, in RefreshProcessVariables
slaves = self.Controler.GetSlaves(**self.CurrentNodesFilter)
File "/home/developer/WorkData/PLC/beremiz/beremiz/etherlab/EthercatMaster.py", line 341, in GetSlaves
for slave in self.Config.getConfig().getSlave():
<type 'exceptions.AttributeError'>:_'lxml.etree._Element'_object_has_no_attribute_'getSlave'

Steps to reproduce problem:

- Add new EtherCAT master
- Add new EthercatNode to the master
- double click on


this is looks like dirty hack to fix strange problem with initial[0]
changing its type after returning from _init_ method to lxml.etree._Element
As a result all methods generated by class factory are lost.

For example, in function initMethod initial[0].__class__ points to
xmlclass.xmlclass.Config. After map(self.append, initial)
self.Config.__class__ is 'xmlclass.xmlclass.Config' as well.
But after returning from initMethod (_init) in CreateElement
self.Config.__class__ has changed to lxml.etree._Element.


I've noticed similar behavior if copy/deepcopy is used for any child
of etree.ElementBase. See simple example below.
[-------------------------------------------------------------]
#!/usr/bin/python

from __future__ import print_function
from lxml import etree
import copy

class DefaultElementClass(etree.ElementBase):
def getLocalTag(self):
return etree.QName(self.tag).localname


def printInformation(x):
print(x, x.__class__, "getLocalTag" in dir(x))


a = DefaultElementClass()
printInformation(a)

#
printInformation(copy.copy(a))
printInformation(copy.deepcopy(a))
[-------------------------------------------------------------]
#!/usr/bin/env python
# -*- coding: utf-8 -*-

# This file is part of Beremiz, a Integrated Development Environment for
# programming IEC 61131-3 automates supporting plcopen standard and CanFestival.
#
# Copyright (C) 2017: Andrey Skvortsov
#
# See COPYING file for copyrights details.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.


from __future__ import absolute_import
import os
import sys

# import pytest
# import xvfbwrapper


def init_environment():
    """Append module root directory to sys.path"""
    try:
        import Beremiz as _Beremiz
    except ImportError:
        sys.path.append(
            os.path.abspath(
                os.path.join(
                    os.path.dirname(__file__), '..', '..')
            )
        )


init_environment()

#
# Something seems to be broken in Beremiz application,
# because after tests in test_application.py during Xvfb shutdown
# pytest returns error message:
# pytest: Fatal IO error 11 (Die Ressource ist zur Zeit nicht verfügbar) on X server :2821.
#
# As a result of that pytest returns code 1 as some tests were failed,
# but they aren't.
#
# To avoid this Xvfb is launched and killed not by pytest.
# $ Xvfb :42 -screen 0 1280x1024x24 &
# $ export DISPLAY=:42
# $ pytest --timeout=10 ./tests/tools
# $ pkill -9 Xvfb
#
# TODO: find root of this problem.


# vdisplay = None
#
# @pytest.fixture(scope="session", autouse=True)
# def start_xvfb_server(request):
#     global vdisplay
#     vdisplay = xvfbwrapper.Xvfb(width=1280, height=720)
#     vdisplay.start()
#     request.addfinalizer(stop_xvfb_server)
#
# def stop_xvfb_server():
#     if vdisplay is not None:
#         vdisplay.stop()