How to reference an object in a class using a decorator

Question

I have a list of dicts defined in setUpClass in a Django TestCase:

class MyTest(TestCase):

    @classmethod
    def setUpClass(cls):

        myobj = MyModel.objects.create()

        cls.MY_LIST = [ 
            ({ 'key1': {'a': myobj.id, 'b': 2}},),
            ({ 'key2': {'a': myobj.id, 'b': 2}},), 
        ]

How do I reference MY_LIST using parameterized? E.g.

@parameterized.expand(MyTest().setUpClass().MYLIST):
def test_mytest(self, dict_item):
    print(dict_item.items())

Results in AttributeError: 'NoneType' object has no attribute 'MYLIST'.

score 0 · Answer 1 · answered Sep 11 '22 at 18:27

0

You can do it. In your case:

class MyTest(TestCase):

    @classmethod
    def setUpClass(cls):
        ... # your staff
        cls.MY_LIST = [...]
        super().setUpClass()
        return cls

Use in tests:

@parameterized.expand(MyTest.setUpClass().MYLIST):
def test_mytest(self, dict_item):
    ... # your test staff

Don't forget, classmethod you can call with class. You are not need instance.

answered Sep 11 '22 at 18:27

Maxim Danilov

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Apologies, typo in my question. It's the same result. – alias51 Sep 12 '22 at 00:04

score 0 · Answer 2 · answered Sep 12 '22 at 00:17

I think the problem is that you're calling setUpClass to add the property MY_LIST, but setUpClass doesn't return nothing. So you can do this things:

MyTest.setUpClass()
@parameterized.expand(MyTest.MYLIST):
def test_mytest(self, dict_item):
    ... # your test staff

or:

class MyTest(TestCase):

    @classmethod
    def setUpClass(cls):

        myobj = MyModel.objects.create()

        cls.MY_LIST = [ 
            ({ 'key1': {'a': myobj.id, 'b': 2}},),
            ({ 'key2': {'a': myobj.id, 'b': 2}},), 
        ]
        return cls

@parameterized.expand(MyTest().setUpClass().MYLIST):
def test_mytest(self, dict_item):
    print(dict_item.items())

Thanks, this approach means `setUpClass()` is called twice – alias51 Sep 12 '22 at 12:02 — alias51, Sep 12 '22 at 12:02

How to reference an object in a class using a decorator

2 Answers2