@0,1⦊async fn i(x: u8) ⦉@0,1{ // line coverage is 1, but there are 2 regions:
                    // (a) the function signature, counted when the function is called; and
                    // (b) the open brace for the function body, counted once when the body is
                    // executed asynchronously.
    match x {
        y if c(x).await == y + 1 => { d().await; }
        y if f().await == y + 1 => (),
        _ => (),
    }
}