Attribute error in TestCaseFunction.teardown when exception encountered before TestCaseFunction.setup is run.

[westhomas]

The sample code below raises an exception in a unittest.TestCase class in the __init__ method. This will produce an exception in TestCaseFunction.teardown() because self._testcase isn't defined, but teardown() attempts to call it here:

pytest/src/_pytest/unittest.py

Line 97 in cbaa7dd

self._testcase.teardown_method(self._obj)

# cat test_setup_exception.py
import unittest
import pytest


class MuhUnitTests(unittest.TestCase):

    def __init__(self):
        raise Exception("testing123")

    def test_passing(self):
        assert True


# Execute Tests
def main():
    pytest.main(['test_setup_exception.py', '-s'])


if __name__ == '__main__':
    main()

self = <TestCaseFunction 'test_passing'>

    def teardown(self):
>       if hasattr(self._testcase, "teardown_method"):
E       AttributeError: 'TestCaseFunction' object has no attribute '_testcase'

../python3.6/site-packages/_pytest/unittest.py:96: AttributeError

Adding a check in teardown for existence of _testcase solves the issue and allows the exception to bubble correctly:

    def teardown(self):
        if hasattr(self, "_testcase") and hasattr(self._testcase, "teardown_method"):
            self._testcase.teardown_method(self._obj)
        # Allow garbage collection on TestCase instance attributes.
        self._testcase = None
        self._obj = None

[asottile]

@westhomas looks good -- want to submit a patch for this? 🎉

[westhomas]

Submitted: #3792

I didn't add any unit tests, but would be happy to if someone wants to give me a little direction into exactly where/how to add one.

[RonnyPfannschmidt]

i believe we should instead ensure that a unittestcase never is in a state where that attribute is missing

[westhomas]

You'd have to at least move self._testcase = self.parent.obj(self.name) from the setup() method into the __init__() method.

But I'm not sure of the impact of that change or whether more of the setup() method should be moved as well. That's above my pay grade ;-)

[RonnyPfannschmidt]

@westhomas existence of the attribute doesnt imply the actual value - if its set to Noneininit` it should be fine

i believe even a hack like setting it on the actual class as class level attribute would suffice

[westhomas]

@RonnyPfannschmidt Good call. Remade PR (#3792) and added unit test: https://github.com/decisio/pytest/blob/aa358433b0d63655981e2bac112ab5a490927716/testing/test_unittest.py#L994-L1012

[bindupatnaik]

I have same issue when i am trying to use init method in pytest class. I tried to un-install and install the pytest to get the latest code fix of the bug. But unfortunately i am not seeing above code fix in my local .
I am using
PS C:\Test\Win10DA> pytest --version
This is pytest version 3.7.1, imported from c:\program files (x86)\python36-32\lib\site-packages\pytest.py

Can anyone guide me how to overcome the problem?
my code looks like below

---

import unittest
from com.xxx.Main import Main
class GUI_tests(unittest.TestCase):

def __init__(self):
        self.main = Main()
        self.logger = logging

    def setUp(self):
        pass
        
    def tearDown(self):
        pass
    
    def test_1(self):
          assert True
        
    def test_2(self):
          assert True

Not sure if i have done something wrong. @westhomas @RonnyPfannschmidt @nicoddemus pls guide. is there any workaround as it is blocker for me now?

[asottile]

Please open a new issue with a stack trace, I suspect this is a different issue (maybe not calling super?)