Close #5603: Autodoc: add :canonical: for everything

[flying-sheep]

Feature or Bugfix

• Feature

Purpose

• Creates a common superclass for all PyObject documenters
• Moves the changes in Close #5603: autodoc: Allow to refer to a python object using canonical name #9026 to that superclass, so functions and methods get thir :canonical: as well

cc @tk0miya

[flying-sheep]

OK, one test fails, how should we fix it?

It happens in a newer Python (e.g. 3.9), in case of a TypeVar that’s a class attribute.

__qualname__ is not set, so the code falls back to __name__, which is wrong.

[tk0miya]

Could you let me know why do you add :canonical: options for everything? In my understanding, nobody refers the canonical functions, methods and others. I'd like to know the real usecase of this.

[flying-sheep]

Everything can be initially defined in one module and be exported in another, not just classes.
As you can see in the test changes, it does happen!

Also I thought that one use case of this is that automatically generated reStructuredText code referring to f'{obj.__module__}.{obj.__qualname__}' works… Only inferring it for classes leaves it broken for functions and methods.

[flying-sheep]

Hi @tk0miya what do you think?

[webknjaz]

@flying-sheep looks like this needs a rebase?

@tk0miya seems like this PR is awaiting your comment too...