On Sat, Jun 26, 2021 at 9:25 AM Daniel Walker <nickel...@gmail.com> wrote:
> I was recently using the cmd module for a project where my CLI
> could connect to and interact with another host. I implemented prompt in
> such a way that it would show the IP address when connected. I.e.,
>
> class MyCmd(cmd.Cmd):
> ...
>
> @property
> def prompt(self) -> str:
> if self.remote_host.connected():
> return f'> ({self.remote_host.ip}) '
> else:
> return '> '
>
> This worked perfectly fine... until I ran mypy. mypy complained because,
> in cmd.Cmd, prompt is a class attribute.
>
> Looking at cmd.py, this seems like an odd design choice as all of the
> references to cmd are through the instance (i.e., self.prompt).
>
You misread the typeshed stub. Where you see these lines in cmd.pyi
class Cmd:
prompt: str
identchars: str
ruler: str
...
those are all instance attribute declarations.
I think that you're running into a different mypy bug, which is that you
can't override a plain attribute with a property in a subclass.
I think there's already a bug for that in the mypy tracker, but I can't
find it right now.
--
--Guido van Rossum (python.org/~guido)
*Pronouns: he/him **(why is my pronoun here?)*
<http://feministing.com/2015/02/03/how-using-they-as-a-singular-pronoun-can-change-the-world/>
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