decohints

decohints

🇷🇺 Версия на русском

A decorator for decorators that allows you to see the parameters of a decorated function when using it in PyCharm.

PyPi: https://pypi.org/project/decohints/

Reasons for creation

Below is an example of a decorator with parameters without the use of decohints:

from functools import wraps


def decorator_with_params(aa=None, bb=None, cc=None):
    def _decorator(func):
        @wraps(func)
        def wrapper(*args, **kwargs):
            try:
                result = func(*args, **kwargs)
            except Exception:
                print("Error")
                return
            return result

        return wrapper

    return _decorator


@decorator_with_params()
def test(a: int, b: int) -> int:
    return a + b

If you type below test() in PyCharm and wait, it will show decorator wrapper parameter hints as test function parameter hints:

This is not convenient and can confuse developers, which is why this library was made.

Installation

pip install decohints

Usage

✅ Works with all kinds of decorators
⚠️ If your decorator is already wrapped in another decorator, then decohints should be on top

To use, you need to follow two simple steps:

1. Import the decohints decorator from the decohints library:

from decohints import decohints

1. Wrap your decorator with a decohints decorator:

@decohints
def your_decorator():
    ...

The following is an example of a decorator with parameters, with using decohints:

from functools import wraps

from decohints import decohints


@decohints
def decorator_with_params(aa=None, bb=None, cc=None):
    def _decorator(func):
        @wraps(func)
        def wrapper(*args, **kwargs):
            try:
                result = func(*args, **kwargs)
            except Exception:
                print("Error")
                return
            return result

        return wrapper

    return _decorator


@decorator_with_params()
def test(a: int, b: int) -> int:
    return a + b

If you type below test() in PyCharm and wait, it will show test function parameter hints:

❕Examples of use with decorator class, class decorators, and more are found at here: click

Alternatives

Specifying the type of wrapper

✅ Works with all kinds of decorator functions

Specifying the type wrapper: func will have the same behavior as using decohints.

Example:

from functools import wraps


def decorator(func):
    @wraps(func)
    def wrapper(*args, **kwargs):
        try:
            result = func(*args, **kwargs)
        except Exception:
            print("Error")
            return
        return result

    wrapper: func
    return wrapper


@decorator
def test(a: int, b: int) -> int:
    return a + b

If you type below test() in PyCharm and wait, it will show test function parameter hints:

Specifying an output type in a decorator with parameters

❗️This method only works in decorator functions with parameters

If you specify the Callable type from the typing module for the result of the decorator with parameters, then the behavior will be the same as using decohints.

Example:

from functools import wraps
from typing import Callable


def decorator_with_params(aa=None, bb=None, cc=None) -> Callable:
    def _decorator(func):
        @wraps(func)
        def wrapper(*args, **kwargs):
            try:
                result = func(*args, **kwargs)
            except Exception:
                print("Error")
                return
            return result

        return wrapper

    return _decorator


@decorator_with_params()
def test(a: int, b: int) -> int:
    return a + b

If you type below test() in PyCharm and wait, it will show test function parameter hints: