[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Raymond Hettinger added the comment: Thanks for the PR :-) -- resolution: -> fixed stage: patch review -> resolved status: open -> closed versions: +Python 3.10 -Python 3.7 ___ Python tracker

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Raymond Hettinger added the comment: New changeset c56387f80c5aabf8100ceaffe365cc004ce0d7e0 by Yurii Karabas in branch 'master': bpo-27794: Add `name` attribute to `property` class (GH-23967) https://github.com/python/cpython/commit/c56387f80c5aabf8100ceaffe365cc004ce0d7e0 --

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Yurii Karabas <1998uri...@gmail.com> added the comment: You a totally right, looks like I tried to add a feature that no one asked for:) I have updated PR and removed `name` parameter from `property` constuctor. Thanks for your advice. -- ___

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Raymond Hettinger added the comment: > In my opinion, it's expected behavior that `name` is > overwritten by `__set_name__` method. It is almost certain that there will be others won't share that expectation. The StackOverflow questions and bug reports are inevitable. Most examples of

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Yurii Karabas <1998uri...@gmail.com> added the comment: Raymond, it's a good question. I have added `name` to `property` constructor to support cases when a property is added to a class after it was declared. For instance: ``` class Foo: pass Foo.foo = property(name='foo') f = Foo()

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Raymond Hettinger added the comment: Yurii, this looks nice. I question whether *name* should be a part of the constructor because it immediately gets overridden by __set_name__ method. >>> class A: ...def x(self): ...return 44 ...x = property(x, name='y') ... >>>

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Yurii Karabas <1998uri...@gmail.com> added the comment: I have implemented this feature using an idea provided by Xiang Zhang. Basically, property has new optional attribute `name` which will be added to msg of `AttributeError` in a case when `name` is set. --

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Change by Yurii Karabas <1998uri...@gmail.com>: -- keywords: +patch nosy: +uriyyo nosy_count: 8.0 -> 9.0 pull_requests: +22812 stage: needs patch -> patch review pull_request: https://github.com/python/cpython/pull/23967 ___ Python tracker

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Change by Anton Patrushev : -- nosy: +apatrushev ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Change by Karthikeyan Singaravelan : -- nosy: +xtreak ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Change by Serhiy Storchaka : -- components: +Interpreter Core nosy: +ncoghlan stage: -> needs patch versions: +Python 3.7 ___ Python tracker

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Muhammad Alkarouri added the comment: Now that the descriptor protocol has `__set_name__`, does this make any difference to this issue? The property can know its name, subject to a suitable patch. -- nosy: +Muhammad Alkarouri ___ Python tracker

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Antti Haapala added the comment: I've got one idea about how to implement this, but it would require adding a new flag field to PyExc_AttributeError type. This flag, if set, would tell that the AttributeError in question was raised in C descriptor code or under similar circumstances, and that

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Xiang Zhang added the comment: One solution I can think of is alter the constructor of property() and add an optional name attribute to it. If users really care about the exception message, they can set the attribute to the property's name. If they don't care, everything remains the same as

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

R. David Murray added the comment: Not worth it. It would feel like boilerplate, and the situation where you want the information is almost invariably going to be one you didn't anticipate and so didn't "bother" with the name. Either that or you always have to do it, and the elegance of

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Emanuel Barry added the comment: Opened #27823 as a followup to this, and carried nosy list over. -- ___ Python tracker ___

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Changes by Xiang Zhang : -- nosy: +xiang.zhang ___ Python tracker ___ ___ Python-bugs-list

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Antti Haapala added the comment: Unfortunately it seems that it is not that straightforward. The descriptor object doesn't know the name of the property. The error is raised in `property_descr_set`. However the error itself can be propagated from setting another property. --

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

Emanuel Barry added the comment: The approach I'd take would be to change how {get,set,del}attr handle AttributeError; possibly by automatically filling in the information and giving a nicer error message. This would fix this as a side-effect (somewhat; some bits of code would need to

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

R. David Murray added the comment: If someone submits a patch in time, we'd probably accept it. -- nosy: +r.david.murray ___ Python tracker ___

[issue27794] setattr a read-only property; the AttributeError should show the attribute that failed

New submission from Antti Haapala: Today we had an internal server error in production. I went to see the sentry logs for the error, and was dismayed: the error was `AttributeError: can't set attribute`, and the faulting line was `setattr(obj, attr, value)` that happens in a for-loop that