Type checking a method call with a default argument prior to keyword argument dictionary-CodePudding

Given

def f_with_opt(opt_arg: bool | None = None, **kwargs):
    print(f"{opt_arg=}, {kwargs=}")


def function() -> None:
    kwargs = {"foo": "bar"}
    f_with_opt(**kwargs)


if __name__ == "__main__":
    function()

mypy reports

test.py:7:18: error: Argument 1 to "f_with_opt" has incompatible type "**Dict[str, str]"; expected "Optional[bool]"  [arg-type]
Found 1 error in 1 file (checked 1 source file)

How can I properly annotate the methods to avoid this error? I've taken a look at https://peps.python.org/pep-0612/ but I don't think it helps in this case. Or does it?

CodePudding user response：

Searching a bit I came across this GitHub issue: https://github.com/python/mypy/issues/5382

And so following this issue, you can fix simply by typing your dictionary with dict[str, Any] Ex:

    kwargs: dict[str, Any] = {"foo": "bar"}

Or you can create a TypedDict, but depending on what you want to do with your dictionary this may seem a bit overkill.