Issue 28265: builtin_function_or_method's getattribute not applicable to self (original) (raw)

Issue28265

Created on 2016-09-24 20:13 by t184256, last changed 2022-04-11 14:58 by admin. This issue is now closed.

Messages (3)
msg277332 - (view)	Author: Alexander Sosedkin (t184256)	Date: 2016-09-24 20:13
I've managed to obtain several objects, which __getattribute__ cannot be applied to them. Minimal non-working example (a more detailed one is attached): b = abs.__class__ b.__getattribute__(b, 'x') Proxying such objects turned out to be even harder that proxying everything else in Python (as if it wasn't already mindbogglingly hard). As you can see, given that 'builtin_function_or_method' object you can obtain its __getattribute__, but you cannot apply it. Tested with Python 3.5.2 and 3.6.0b1. What's the deal with that broken __getattribute__? It seems to be specific to 'builtin_function_or_method' class, but why is it broken? If it is "PyObject_GenericGetAttr", then why object.__getattribute__(b, 'x') works? What am I missing?
msg277338 - (view)	Author: Eric Snow (eric.snow) *	Date: 2016-09-24 21:52
Hmm. It's not clear what you're after here. The error from your example code is correct. The valid invocation is: b.__getattribute__(abs, 'x') That works just fine. If you want to look up *class* attributes then you must call __getattribute__ on the class's class: type(b).__getattribute__(b, 'x') This is how attribute lookup works. I recommend closing this as not-a-bug. If you have further question your best bet is to ask on the python-list mailing list.
msg277345 - (view)	Author: Alexander Sosedkin (t184256)	Date: 2016-09-25 04:58
Oh, I see. The invocation b.__getattribute__(b, attrname) worked on so many objects that I didn't even think it could be incorrect. Sorry for wasting your time.