Skip to content

type hint FunctionWrapper #288

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
grayjk wants to merge 4 commits into from
+25 −0
Closed

type hint FunctionWrapper #288

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
98b1e4e
type hint FunctionWrapper
grayjk Jul 21, 2025
dd27038
TypeVar instead of ParamSpec
grayjk Jul 25, 2025
0126ea1
pytest-mypy
grayjk Jul 31, 2025
0098662
Only install pytest-mypy-plugin for Python 3.9+.
GrahamDumpleton Aug 1, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
1 change: 1 addition & 0 deletions setup.cfg
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -91,6 +91,7 @@ python =
deps =
coverage
pytest
pytest-mypy-plugins; python_version >= "3.9"
install_command =
python -m pip install --no-binary coverage {opts} {packages}
commands =
Expand Down
5 changes: 5 additions & 0 deletions src/wrapt/__init__.pyi
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,5 @@
from typing import Callable, TypeVar

F = TypeVar("F", bound=Callable)

def FunctionWrapper(wrapped: F, wrapper: Callable) -> F: ...
Copy link
Owner

@GrahamDumpleton GrahamDumpleton Aug 1, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Would this all be more precisely defined as:

from typing import Callable, TypeVar, Any, Tuple, Dict, Union

WrappedFunction = TypeVar("WrappedFunction", bound=Callable)

# Standard signature for wrappers
StandardWrapper = Callable[[WrappedFunction, Any, Tuple[Any, ...], Dict[str, Any]], Any]

# Catch-all wrapper signature
CatchAllWrapper = Callable[..., Any]

# Union type to accept either wrapper style
WrapperFunction = Union[StandardWrapper, CatchAllWrapper]

def FunctionWrapper(
    wrapped: WrappedFunction, wrapper: WrapperFunction
) -> WrappedFunction: ...

The standard wrapper would be:

    def standard_wrapper(wrapped, instance, *args, **kwargs):
        pass

It would be rare, but someone may want to instead define this as:

    def catch_all_wrapper(*args, **kwargs):
        pass

Anyway, starting to understand what I need to do. Just working out easy way of maintaining the tests. It is a pain to have to add in the out section with exact line numbers.

1 change: 1 addition & 0 deletions src/wrapt/py.typed
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1 @@
partial
18 changes: 18 additions & 0 deletions tests/test_mypy.yml
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,18 @@
- case: function_wrapper
main: |
from wrapt import FunctionWrapper

def x(a: bool, b: str) -> int:
return 1

def wrapper(*args, **kwargs):
pass

x = FunctionWrapper(x, wrapper)
reveal_type(x)

x(1, None)
out: |
main:10: note: Revealed type is "def (a: builtins.bool, b: builtins.str) -> builtins.int"
main:12: error: Argument 1 to "x" has incompatible type "int"; expected "bool" [arg-type]
main:12: error: Argument 2 to "x" has incompatible type "None"; expected "str" [arg-type]
Loading