Proc_derive_macro, proc_attribute_macro, IntelliJ auto completion

In my current experience: proc_derive_macro / macro_rules! works fine with IntelliJ intellisense (auto completion, goto def/impl, etc ...).

However, proc_attribute_macro seems to be INVISIBLE to IntelliJ. Concretely, consider the following attribute macro:

#[proc_macro_attribute]
pub fn fwd_decl(attr: proc_macro::TokenStream, input: proc_macro::TokenStream) -> proc_macro::TokenStream {
    input
}

So this macro does nothing, except output it's input (i.e. it is an "identity" macro).

Now, consider the following usage:

pub struct Foo {}

#[fwd_decl]
impl Foo {
    pub fn new() -> Foo {
        Foo {}
    }

    pub fn other(&self) -> u32 {
        0
    }
}

#[test]
fn it_works() {
    let f = Foo::new();

    f.other();
}

The unit test compiles and runs fine (so the "identity" macro is working), but IntelliJ is broken on ::new() , .other(), and the return type of Foo::new().

Question: is there anyway to make this work?

I think I have all the proc macro options turned on: