[issue21919] Changing cls.__bases__ must ensure proper metaclass inheritance

2018-09-28 Thread Guido van Rossum
Guido van Rossum added the comment: As long as you can't crash CPython with this, this is the responsibility of the code that assigns to __bases__. If they don't take care, the program's behavior is undefined. -- ___ Python tracker

[issue21919] Changing cls.__bases__ must ensure proper metaclass inheritance

2018-09-28 Thread Raymond Hettinger
Raymond Hettinger added the comment: > I am adding Raymond as part of triaging who might have a better explanation > about this. Guido, is this something we care about? There is value in checking for metaclass conflicts when a class is created (to catch plausible mistakes and to assure

[issue21919] Changing cls.__bases__ must ensure proper metaclass inheritance

2018-09-27 Thread Karthikeyan Singaravelan
Karthikeyan Singaravelan added the comment: Thanks for the report and patience. This behavior is still reproducible on master as of f55c64c632 . I am adding Raymond as part of triaging who might have a better explanation about this. Raymond, feel free to remove yourself if this is not

[issue21919] Changing cls.__bases__ must ensure proper metaclass inheritance

2018-09-23 Thread Mark Lawrence
Change by Mark Lawrence : -- nosy: -BreamoreBoy ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue21919] Changing cls.__bases__ must ensure proper metaclass inheritance

2018-09-23 Thread Karthikeyan Singaravelan
Change by Karthikeyan Singaravelan : -- nosy: +xtreak ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue21919] Changing cls.__bases__ must ensure proper metaclass inheritance

2015-03-02 Thread Eldar Abusalimov
Eldar Abusalimov added the comment: @Mark, that OK, for the issue without a patch. :) I could make a patch, but I'm not sure whether the proposed behavior is right. It could be considered arguable, I guess... -- ___ Python tracker

[issue21919] Changing cls.__bases__ must ensure proper metaclass inheritance

2015-02-27 Thread Mark Lawrence
Mark Lawrence added the comment: @Eldar sorry that this issue slipped our net. -- nosy: +BreamoreBoy versions: +Python 3.5 -Python 3.2 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue21919 ___

[issue21919] Changing cls.__bases__ must ensure proper metaclass inheritance

2014-07-04 Thread Eldar Abusalimov
New submission from Eldar Abusalimov: When a new class is constructed Python checks for possible metaclass conflicts within bases and an explicitly specified one, if any, choosing the best available (the most specialized) one. That is the following implication is expected: issubclass(B,