Typehints derived from type comments not properly handled in generated signature and parameters

[fmigneault]

When type hints are generated for class methods that provide the types using the comment annotation format, some cases are not handled correctly. (i.e.: using # type: (<args>) -> <return>)

1. Base classes are replaced by the first argument from their corresponding __init__ call.
   For some reason, the Parameters section for the class' __init__ are not reported anywhere.
   (maybe because they are already processed as base class components, instead of self, so no more parameters to process?)
2. Parameters in other methods have their types offset by one.

All this is most definitely caused by inspect.signature that does not include self or cls definitions, since they are not to be provided type comments definitions (similar to how the instance reference is automatically passed during the method call and must not be passed as argument).
Instead of inspect.siganture, one should use inspect.getfullargspec to obtain the full arguments derived from type comments, including self for methods or cls for classmethods.

Use cases are demonstrated in below images.

using autodoc_typehints = "description"

with autodoc_typehints disabled

corresponding code:

source code for reference: https://github.com/Ouranosinc/Magpie
and config: https://github.com/Ouranosinc/Magpie/blob/master/docs/conf.py

[mathbou]

I made a PR (#300) months ago about this problem, still waiting for review 😕

[AWhetter]

Apologies for taking so long to look at #300. That PR has now been merged so please let me know if this is still an issue.

[AWhetter]

Closing due to lack of feedback and assuming that the merged pull request fixed this issue.