[Python-Dev] python and super

[Ricardo Kirkner]

>
> What would the semantics be of a super that intentially calls all siblings? In particular what is the return value of such a call? The implementation can't know how to combine the implementations in the inheritance chain and should refuse the tempation to guess.

I'll give you the example I came upon:

I have a TestCase class, which inherits from both Django's TestCase
and from some custom TestCases that act as mixin classes. So I have
something like

class MyTestCase(TestCase, Mixin1, Mixin2):
   ...

now django's TestCase class inherits from unittest2.TestCase, which we
found was not calling super. Even if this is a bug and should be fixed
in unittest2, this is an example where I, as a consumer of django,
shouldn't have to be worried about how django's TestCase class is
implemented. Since I explicitely base off 3 classes, I expected all 3
classes to be initialized, and I expect the setUp method to be called
on all of them.

If I'm assuming/expecting unreasonable things, please enlighten me.
Otherwise, there you have a real-world use case for when you'd want
the sibling classes to be called even if one class breaks the mro
chain (in this case TestCase).

Thanks,
Ricardo