Rustdoc: leaves alias type's documetation empty

[timthelion]

Types that are generated by a macro from another type using a decorator end up with empty documentation. Here is an example

I expected to see this happen: I expected to see the fields and methods I can use with objects of this type. For example, I know from context that this type has a content attribute but no such attribute is shown in the docs.

Example code from the same project:

async fn on_room_message(event: OriginalSyncRoomMessageEvent, room: Room) {
    if let Room::Joined(room) = room {
        let MessageType::Text(text_content) = event.content.msgtype else {
            return;
        };

        if text_content.body.contains("!party") {
            let content = RoomMessageEventContent::text_plain("🎉🎊🥳 let's PARTY!! 🥳🎊🎉");

            println!("sending");

            // send our message to the room we found the "!party" command in
            // the last parameter is an optional transaction id which we don't
            // care about.
            room.send(content, None).await.unwrap();

            println!("message sent");
        }
    }
}

Instead, this happened:

[jyn514]

@timthelion do you see the same problem if you write out the type alias without a macro? If so, it's probably related to the alias, not the macro.

[timthelion]

I'm sorry but I don't know what the type alias without the macro is. I didn't write the code in question and I'm still quite new to rust.

[jyn514]

The one shown in the docs, pub type OriginalSyncRoomMessageEvent = OriginalSyncMessageLikeEvent<RoomMessageEventContent>;

[timthelion]

Oh, wow, I didn't realize that. So basically it would be fixed if the docs contained the same thing as this page https://docs.rs/ruma/0.7.4/ruma/events/struct.OriginalSyncMessageLikeEvent.html but with C replaced with RoomMessageEventContent. Or maybe we can somehow detect that there is a type alias and change the UX like so:

[fmease]

Duplicate of feature request #99952.

[timthelion]

@fmease yeah, probably, thanks.