How to forward inputs when transitioning a target?

[cbarrete]

Say I work around #832 by writing a rule like:

my_transitioned_target = rule(
    impl = lambda ctx: ctx.attrs.base.providers,
    attrs = {
        # `my_transition` just adds `my_constraint` to the configuration.
        "base": attrs.transition_dep(cfg = my_transition),
        "my_constraint": attrs.label(),
    },
)

If I add a target using this rule and query its inputs (using either the CLI or BXL), I get an empty list. This kind of makes sense to me, but from an end-user perspective, I'd like my transitioned target to mostly behave like the base one, including carrying the same inputs. Is there a way that I can achieve that?

I've tried working around that by adding an arg attr that I populate with a $(query_outputs inputs(:my_base_target)) string parameter macro, but then I run into configuration incompatibility issues because the base and transitioned targets are incompatible.

Any help would be greatly appreciated!