ensure_types.py

# -*- coding: utf-8 -*-

import functools


def ensure_types(f):
    @functools.wraps(f)
    def wrapper(*args: list, **kwargs: dict):
        if f.__annotations__:
            for arg in args:
                if not isinstance(arg, f.__annotations__[arg]):
                    raise TypeError('Argument "{0}" should be of type {1}'.format(arg, f.__annotations__[arg]))

            f(*args, **kwargs)

    return wrapper


@ensure_types
def test(a: str, b: str, c: str) -> str:
    return a, b, c


if __name__ == '__main__':
    print(dir(test('a', 'b', 'c')))
    print(dir(test(1, 2, 3)))