Check if decorator returns use keyword (unexpected-keyword-arg)

[DanielNoord]

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Type of Changes

	Type
✓	🐛 Bug fix

Description

Closes #258 (🎉)

I'd like to see the coverage report on this. I might need to add some additional tests.

[coveralls]

Pull Request Test Coverage Report for Build 1594454584

• 21 of 21 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.009%) to 93.689%

---

Totals
Change from base Build 1594420876:	0.009%
Covered Lines:	14295
Relevant Lines:	15258

---

💛 - Coveralls

[DanielNoord]

Blocked by #5549. Rest of the tests and coverage look good so this is ready for review.

[Pierre-Sassoulas]

It's heart-warming to see really old issues getting addressed 🎉

[Pierre-Sassoulas]

The tests are on point !

[Pierre-Sassoulas]

Not really related to this MR but if we have to handle confidence level, this kind of return where we do not exactly know if inference was used or not in the calling code will be a headache later. Makes me thing that implementing confidence properly will be an enormous work, maybe not even worth it.

[DanielNoord]

Thankfully we have UNDEFINED 😄

[martimlobao]

@DanielNoord maybe I should open a new ticket, but just tried this out with the latest version of the main branch and there seems to be a case where this is still raising a false positive unexpected-keyword-arg error. Here's a MWE:

def example_decorator(*new_func_args, **new_func_kwargs):
    def decorator(func):
        def wrapper(*args, **kwargs):
            print_me = kwargs.pop("print_me", None)
            def inner(*inner_args, **inner_kwargs):
                print(print_me)
                return func(*inner_args, **inner_kwargs)

            return inner(*args, **kwargs)

        return wrapper

    if len(new_func_args) == 1 and len(new_func_kwargs) == 0 and callable(new_func_args[0]):
        return decorator(new_func_args[0])
    return decorator

@example_decorator
def example_func(num):
    return num ** 2

example_func(6, print_me="hello")

(Note that no error is raised by pylint if we remove the top-level function (example_decorator). The reason for someone to define the decorator this way is so that it's possible to use the bare @example_decorator, as well as with arguments @example_decorator(foo=1).)

Using pylint on commit hash e75e37a, this is the error that's printed out:

E1123: Unexpected keyword argument 'print_me' in function call (unexpected-keyword-arg)

Calling example_func works fine:

>>> example_task(6, print_me="hello")
hello
36

[DanielNoord]

Ah yes, this won't be catched. Not sure how easy it would be to implement looking for inner return values.
In any case, I think this warrants its own issue. Could you open it?

[martimlobao]

Ah yes, this won't be catched. Not sure how easy it would be to implement looking for inner return values. In any case, I think this warrants its own issue. Could you open it?

Sorry for taking forever, but finally opened the ticket :)

[DanielNoord]

Thanks @martimlobao! Totally forgot about this myself.

[martimlobao]

Thanks @martimlobao! Totally forgot about this myself.

lol sorry for the ridiculously incomplete title, i started writing it and then forgot to finish 🤦‍♂️