AST resolver - support super with arbitrary parameters

[t-mesq]

🚀 Feature request

Currently (v4.12.0) the AST resolver fails when resolving calls to super that don't follow the immediate MRO (i.e., super(SubClass, self) for class SubSubClass(SubClass)). This used to be possible in <=v4.9.0, so would it be possible for AST resolver to handle these cases?

To reproduce

from jsonargparse import ArgumentParser

class BaseClass:
    def __init__(self, base_arg: int, *args, base_kwarg: str="base", **kwargs):
        self.base_arg = base_arg
        self.base_kwarg = base_kwarg

class SubClass(BaseClass):
    def __init__(self, *args, sub_kwarg: str="sub", **kwargs):
        super().__init__(*args, **kwargs)
        self.sub_kwarg = sub_kwarg

class SubSubClass(SubClass):
    def __init__(self, *args, subsub_kwarg: str="subsub", **kwargs):
        super(SubClass, self).__init__(*args, **kwargs). # <- 
        self.subsub_kwarg = subsub_kwarg

config = {"class_path": "SubSubClass", "init_args": {"base_arg": 3}}
parser = ArgumentParser()
parser.add_argument('--myclass', type=BaseClass)
print(parser.parse_args(["--myclass", str(config)]))

Running the script in v4.9.0 results in:

Namespace(myclass=Namespace(class_path='__main__.SubSubClass', init_args=Namespace(base_arg=3, base_kwarg='base', sub_kwarg='sub', subsub_kwarg='subsub')))

which is a valid initialisation for SubSubClass, though sub_kwarg isn't necessary.
In v4.12.0 (with JSONARGPARSE_DEBUG enabled), however, it results in an error:

...
2022-07-27 11:59:33,895 - ArgumentParser - DEBUG - AST resolver: super with arbitrary parameters not supported: Call(func=Attribute(value=Call(func=Name(id='super', ctx=Load()), args=[Name(id='SubClass', ctx=Load()), Name(id='self', ctx=Load())], keywords=[]), attr='__init__', ctx=Load()), args=[Starred(value=Name(id='args', ctx=Load()), ctx=Load())], keywords=[keyword(arg=None, value=Name(id='kwargs', ctx=Load()))])
2022-07-27 11:59:33,902 - ArgumentParser - ERROR - 'Configuration check failed :: No action for destination key "base_arg" to check its value.'
2022-07-27 11:59:33,906 - ArgumentParser - ERROR - Parser key "myclass": Problem with given class_path "__main__.SubSubClass":
...

Expected behavior

If possible, I would expect the previous script to produce:

Namespace(myclass=Namespace(class_path='__main__.SubSubClass', init_args=Namespace(base_arg=3, base_kwarg='base', subsub_kwarg='subsub')))

Environment

• jsonargparse version: 4.12.0
• Python version: 3.9
• How jsonargparse was installed: pip install jsonargparse
• OS: Linux

Thank you in advance!

[mauvilsa]

Thank you for reporting. In v4.9.0 the fact that sub_kwarg is in the namespace is not just about being unnecessary. If BaseClass didn't have **kwargs, it would fail on instantiation, i.e.

>>> cfg = parser.parse_args(["--myclass", str(config)])
>>> parser.instantiate_classes(cfg)
...
TypeError: __init__() got an unexpected keyword argument 'sub_kwarg'

Super with arbitrary parameters wasn't supported in v4.9.0 and it isn't supported in v4.12.0. This isn't really a bug, but a feature request. Changing the labels accordingly.

[mauvilsa]

This new feature has been implemented in commit 1751fe7.

[t-mesq]

Thank you for getting on this so quickly!