Author Jelle Zijlstra
Recipients Jelle Zijlstra, levkivskyi, ncoghlan, yselivanov
Date 2017-05-04.03:37:31
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Like other ABCs, contextlib.AbstractContextManager should support the pattern where setting a method to None disables structural subtyping, which was introduced across the standard library in issue 25958. Ivan Levkivskyi suggested making AbstractContextManager support this pattern in CR comments in

Should this change be applied to 3.6 as well as master? I'm leaning towards yes, because the resolution to issue 25958 ( added a general statement in the documentation that "Setting a special method to ``None`` indicates that the corresponding operation is not available". Thus, the fact that contextlib.AbstractContextManager doesn't obey this rule is a bug.

I'll send a PR shortly.
Date User Action Args
2017-05-04 03:37:32Jelle Zijlstrasetrecipients: + Jelle Zijlstra, ncoghlan, yselivanov, levkivskyi
2017-05-04 03:37:32Jelle Zijlstrasetmessageid: <>
2017-05-04 03:37:32Jelle Zijlstralinkissue30266 messages
2017-05-04 03:37:31Jelle Zijlstracreate