Closed
Description
Crash Report
mypy crashes on callable frozen dataclass
Traceback
➜ mypy-bug poetry run mypy mypy_bug/case_3.py --show-traceback
mypy_bug/case_3.py:14: 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: 0.931
Traceback (most recent call last):
File "mypy/semanal.py", line 5142, in accept
File "mypy/nodes.py", line 1005, in accept
File "mypy/semanal.py", line 1105, in visit_class_def
File "mypy/semanal.py", line 1184, in analyze_class
File "mypy/semanal.py", line 1193, in analyze_class_body_common
File "mypy/semanal.py", line 1239, in apply_class_plugin_hooks
File "mypy/plugins/dataclasses.py", line 489, in dataclass_class_maker_callback
File "mypy/plugins/dataclasses.py", line 194, in transform
File "mypy/plugins/dataclasses.py", line 431, in _freeze
AssertionError:
mypy_bug/case_3.py:14: : note: use --pdb to drop into pdbTo Reproduce
from dataclasses import dataclass
from typing import Any, Callable
# here both `Parent` and `Child` are frozen dataclasses
@dataclass(frozen=True)
class Parent:
__call__: Callable[..., None]
def __call__(self, *args: Any, **kwargs: Any) -> None: # type: ignore
raise NotImplementedError
@dataclass(frozen=True)
class Child(Parent):
def __call__(self, value: int) -> None:
...Your Environment
- Mypy version used: 0.931
- Mypy command-line flags: None
- Mypy configuration options from
mypy.ini(and other config files): None - Python version used: 3.10.0
- Operating system and version: macOS Catalina (10.15)
I'm using "Guido's hack" from #9560 (comment) which does work in other circumstances:
from typing import Any, Callable
# here both `Parent` and `Child` are "regular" classes
class Parent:
__call__: Callable[..., None]
def __call__(self, *args: Any, **kwargs: Any) -> None: # type: ignore
raise NotImplementedError
class Child(Parent):
def __call__(self, value: int) -> None:
...from dataclasses import dataclass
from typing import Any, Callable
# here `Parent` is a frozen dataclass, but `Child` is not
@dataclass(frozen=True)
class Parent:
__call__: Callable[..., None]
def __call__(self, *args: Any, **kwargs: Any) -> None: # type: ignore
raise NotImplementedError
class Child(Parent):
def __call__(self, value: int) -> None:
...from dataclasses import dataclass
from typing import Any, Callable
# here both `Parent` and `Child` are dataclasses, but not frozen
@dataclass
class Parent:
__call__: Callable[..., None]
def __call__(self, *args: Any, **kwargs: Any) -> None: # type: ignore
raise NotImplementedError
@dataclass
class Child(Parent):
def __call__(self, value: int) -> None:
...