click annotation validation

click_decorator.py

import typing as t

import click


def deco(f):
    f = click.option("--foo")(f)
    f = click.option("--bar", type=int)(f)
    return f


@click.command
@deco
def frobulate(*, foo: str | None, bar: int | None) -> None:
    pass


@deco
@click.command
def demuddle(*, foo: str | None, bar: int | None) -> None:
    pass


# art deco args are arg_deco?
def assert_is_arg_deco(f):
    if isinstance(f, click.Command):
        hints = t.get_type_hints(f.callback)
    else:
        hints = t.get_type_hints(f)
    assert "foo" in hints
    assert "bar" in hints

    assert hints["foo"] == t.Union[str, None]
    assert hints["bar"] == t.Union[None, int]


assert_is_arg_deco(frobulate)
assert_is_arg_deco(demuddle)

simple.py

import random
import typing as t


def foo(x: int, y: str | bool) -> t.Any:
    if random.random() < 0.5:
        return x
    return y


def bar(x: int) -> str:
    return str(x)


def takes_y_arg(c) -> bool:
    annotations = t.get_type_hints(c)
    if "y" not in annotations:
        return False
    if annotations["y"] != t.Union[bool, str]:
        return False
    return True


print(takes_y_arg(foo))
print(takes_y_arg(bar))