NameError: name '__beartype_random_int' is not defined

Since the glorious update to 0.3, I encountered a slight issue with using lists of pathlib Path objects. I’m not sure whether it is specific to pathlib Paths in particular, but this was what I whittled it down to as a minimal script that produces the issue:

from typing import List
from pathlib import Path

from beartype import beartype


class UserDefinedType:

    def __repr__(self):
        return "I am a user-defined type"


@beartype
def working_example(x: List[Path]):
    print(f"working_example >>> I will get to see {x}")


@beartype
def working_combination(x: List[int], y: int):
    print(f"working_combination >>> I get to see {x} and {y}")


@beartype
def working_combination_udt(x: List[UserDefinedType], y: int):
    print(f"working_combination with UDT >>> I get to see {x} and {y}")


@beartype
def not_working_combination(x: List[Path], y: int):
    print(f"not_working_combination: Sadly, I will never see {x} or {y}")


if __name__ == "__main__":
    path_list = [Path("/a/b")]
    int_list = [0]
    udt_list = [UserDefinedType()]

    # works OK
    working_example(x=path_list)
    working_combination(x=int_list, y=0)
    working_combination_udt(x=udt_list, y=0)

    # breaks
    not_working_combination(x=path_list, y=0)

This produces the output:

working_example >>> I will get to see [PosixPath('/a/b')]
working_combination >>> I get to see [0] and 0
working_combination with UDT >>> I get to see [I am a user-defined type] and 0
Traceback (most recent call last):
  File "debug.py", line 43, in <module>
    not_working_combination(x=path_list, y=0)
  File "<string>", line 25, in __beartyped_not_working_combination
NameError: name '__beartype_random_int' is not defined

It’s easy for me to work around for now by reverting to using list as an annotation (rather than List[Path]), but just thought I’d flag it as a potential issue.

[leycec]

Ka-blammo! beartype 0.3.1 is up on all the usual suspects. This turned out to be a surprisingly involved issue. On the bright side, we’ve resolved a critical memoization defect and written unit tests exhaustively exercising this defect across all possible edge cases. On the dark side, this should never have happened.

But that’s 2020 for you. Urgh!

[leycec]

Ah-ha! It’s an obscure function memoization issue. You really don’t want to know. This is why friends don’t let friends memoize drunk, people.

I’ll have this patched up and beartype 0.3.1 pushed out the Canadian cabin door in a jiffy.