isinstance doesn't work with interfaces

[pythonnet]

isinstance doesn't work with interfaces

[filmor]

Could you give more details on how this could be implemented?

[tonyroberts]

I've not really looked in too much detail I'm afraid, but I was thinking that if tp_bases on the type structure was set to a tuple of base classes, including the interfaces, then that would make isinstance work. From memory, I think currently tp_base is set and tp_bases is set to NULL.

[filmor]

Looking a bit deeper into this, I think this should be implemented in the metaclass instead, by means of __instancecheck__ (works only from 2.6 onwards, but that should be enough). If you add the interfaces to tp_bases it will fail on method resolution as "mro() returned base class with unsuitable layout". In the end, the interfaces aren't really base classes anyway.

[den-run-ai]

@filmor is this now implemented in your pull request here?

#167

[filmor]

Yep, it is.

[tonyroberts]

Fixed in #167.