How can a python base class tell whether a sub class has overridden its methods?

Question

Here is my guess, which doesn\'t work:

class BaseClass(object):
    def foo(self):
        return \'foo\'
    def bar(self):
        return \'bar\'
    def m         


        

Answer 1

Perhaps this?

>>> class BaseClass(object):
...     def foo(self):
...         return 'foo'
...     def bar(self):
...         return 'bar'
...     def methods_implemented(self):
...         """This does work."""
...         overriden = []
...         for method in ('foo', 'bar'):
...             this_method = getattr(self, method)
...             base_method = getattr(BaseClass, method)
...             if this_method.__func__ is not base_method.__func__:
...                 overriden.append(method)
...         return overriden
... 
>>> class SubClass(BaseClass):
...     def foo(self):
...         return 'override foo'
... 
>>> o = SubClass()
>>> o.methods_implemented()
['foo']

This checks whether the function objects behind the bound methods are the same.

Note, prior to Python 2.6, the __func__ attribute was named im_func.