Room tenancies, find lost commits

[hw0lff]

With this PR, the person_id is also shown in the webview, even if no user could be mapped.

[lukasjuhrich]

Using nested functions with one invocation is nonsense unless you have a really good reason. Here, you could've used a plain variable if you don't like the line length.

Otherwise, if we want to do null coalescence anyway, apart from fancy solutions we could just bake the null coalescence into user_button (changing its signature to User | None -> str | None)

[hw0lff]

I'm not sure a variable would be applicable here since it is used in a list comprehension. Avoiding long lines was the intention but let's inline these functions if there is not a better way to do it.

[lukasjuhrich]

Right, sorry, I overlooked the list comprehension. Then I'm not sure and I would just vouch for inlining, purely because weakening user_button changes semantics.

[lukasjuhrich]

I mean the other way would be the fancy bs way:

def lift[A, B](f: Callable[[A], B | None]) -> Callable[[A | None], B | None]:
    def _lifted(a: A | None) -> B | None:
        return f(a) if a is not None else None
    return _lifted

and then use lift(user_button)(tenancy.user)

[lukasjuhrich]

(beware, untested)

[hw0lff]

Can the condition if tenancy.user is not None else None be shortened to if tenancy.user else None or does it change the meaning?
Same question for tenancy.person_id in line 621.

[lukasjuhrich]

Yes, since sqlalchemy objects are falsy iff they are None.