Wrong type hint of DOMNode.watch method

[mzebrak]

It looks like after the latest changes 0.11.0 (because in 0.10.1 there was no issue), the wrong type hint was used for DOMNode.watch method.

After upgrading textual in my project I see mypy errorrs like below:

Argument 3 to "watch" of "DOMNode" has incompatible type "Callable[[Any], None]"; expected "Union[Callable[[], Awaitable[None]], Callable[[], None]]"  [arg-type]

After some investigation, argument no.3 in the 0.11.0 is:

callback: CallbackType,

which is:

CallbackType = Union[Callable[[], Awaitable[None]], Callable[[], None]]

This is not true because Callabe can take additional arguments - current_value and previous_value (both of the Any type).

Previously, in the reactive.watch method, it was:

 callback: Callable[[Any], object]

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[mzebrak]

@willmcgugan This one is not fixed in 0.13.0 so shouldn't be closed.

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[mzebrak]

@willmcgugan
0.14.0 fixed most of the errors, but there is still one minor issue:

error: Argument "callback" to "watch" of "DOMNode" has incompatible type "Callable[[], None]"; expected "Union[Callable[[Any], Awaitable[None]], Callable[[Any], None]]"  [arg-type]

It shows up when I attach callback method without any params:

self.watch(self.app, "something", callback=self.__sync_cart_items)

def __sync_cart_items(self) -> None:
    pass

I have to apply workaround such as:

self.watch(self.app, "something", callback=self.__sync_cart_items)

def __sync_cart_items(self, _: Something) -> None:
    pass