Issue2581

As discovered in https://github.com/pypa/setuptools/issues/1024#issuecomment-297586140, invoking inspect.getmro on a class whose bases include two or more classes with the same __name__ will return only the first one encountered. This script demonstrates the issue:

class OtherNamespace:
	class Y:
		pass

class Y:
 pass

class Z(OtherNamespace.Y, Y):
 pass

import inspect

print(inspect.getmro(Z))

Very interesting. Likely an easy fix by being more precise - identity vs name.

>>> OtherNamespace.Y == Y
True

Oops. The problem is PyClass.__cmp__.

We definitely want == (and !=) to be based on object identity, but it's not obvious what < should be. We can't have a<b and b<a both false and yet not have a==b which would be so if we still based it on name. If I've understood CPython correctly it compares by memory address.

Not sure this is a showstopper for 2.7.2 but leaving it so marked.

Not a *showstopper* for 2.7.2, but a fix is welcome.