Closed
Description
Crash Report
I'm developing an cache decorator that uses ParamSpec to be as generic as possible.
There's a slight bug in my code (I used Sequence where I should have used Paramspec.args), but I feel that shouldn't have led to a crash. There might actually be legitimate usecases for the incorrect code I wrote.
Traceback
mypy_bug_test.py:22: error: INTERNAL ERROR -- Please try using mypy master on GitHub:
https://mypy.readthedocs.io/en/stable/common_issues.html#using-a-development-mypy-build
Please report a bug at https://github.com/python/mypy/issues
version: 1.11.2
Traceback (most recent call last):
File "mypy/checkexpr.py", line 5822, in accept
File "mypy/checkexpr.py", line 480, in visit_call_expr
File "mypy/checkexpr.py", line 614, in visit_call_expr_inner
File "mypy/checkexpr.py", line 1467, in check_call_expr_with_callee_type
File "mypy/checkexpr.py", line 1597, in check_call
File "mypy/checkexpr.py", line 1561, in check_call
File "mypy/checkexpr.py", line 1746, in check_callable_call
File "mypy/checkexpr.py", line 2062, in infer_function_type_arguments
File "mypy/checkexpr.py", line 2268, in get_arg_infer_passes
File "mypy/subtypes.py", line 1248, in find_member
File "mypy/subtypes.py", line 1383, in find_node_type
File "mypy/expandtype.py", line 114, in expand_type_by_instance
File "mypy/expandtype.py", line 69, in expand_type
File "mypy/types.py", line 2004, in accept
File "mypy/expandtype.py", line 408, in visit_callable_type
File "mypy/expandtype.py", line 500, in expand_types
File "mypy/types.py", line 769, in accept
File "mypy/expandtype.py", line 264, in visit_param_spec
AssertionError:
mypy_bug_test.py:22: : note: use --pdb to drop into pdb
To Reproduce
This is how far I've managed to whitle my testcase down:
from collections.abc import Callable, Sequence
import functools
from typing import Generic, ParamSpec, TypeVar
P = ParamSpec("P")
R = TypeVar("R")
class DecoratorImplementation(Generic[P, R]):
def __init__(self,
fn: Callable[P, Sequence[R]], param):
self.fn = fn
self.param = param
def __call__(self, *args: Sequence, **kwargs: P.kwargs):
def wrapper(*args, **kwargs):
return self.fn(*args, **kwargs)
return wrapper
def decorator(func, param):
def decorator_inner(fn):
return functools.wraps(fn)(DecoratorImplementation(fn, param))
return decorator_innerYour Environment
Operating system: Debian Bookworm, python 3.11, virtualenv
mypy versions tested:
- mypy 1.11.2 (compiled: yes) (affected) 🔴
- mypy 1.10.0 (compiled: yes) (affected) 🔴
- mypy 1.9.0 (compiled: yest) (NOT affected) 🟢
pyproject.toml:
[tool.mypy]
python_version = "3.11"
ignore_missing_imports = true
show_error_codes = true
check_untyped_defs = true
exclude = "tests/.*\\.py"
[[tool.mypy.overrides]]
module = "internal.config_py.*"
# lots of dict-heavy code which isn't typed at all.
ignore_errors = true