27 lines
738 B
Rust
27 lines
738 B
Rust
|
use darling::{util::parse_expr, FromDeriveInput, FromMeta};
|
||
|
|
use syn::{parse_quote, Expr};
|
||
|
|
|
||
|
|
#[derive(FromDeriveInput)]
|
||
|
|
#[darling(attributes(demo))]
|
||
|
|
pub struct Receiver {
|
||
|
|
#[darling(with = parse_expr::preserve_str_literal, map = Some)]
|
||
|
|
example1: Option<Expr>,
|
||
|
|
#[darling(
|
||
|
|
// A closure can be used in lieu of a path.
|
||
|
|
with = |m| Ok(String::from_meta(m)?.to_uppercase()),
|
||
|
|
default
|
||
|
|
)]
|
||
|
|
example2: String,
|
||
|
|
}
|
||
|
|
|
||
|
|
fn main() {
|
||
|
|
let input = Receiver::from_derive_input(&parse_quote! {
|
||
|
|
#[demo(example1 = test::path, example2 = "hello")]
|
||
|
|
struct Example;
|
||
|
|
})
|
||
|
|
.unwrap();
|
||
|
|
|
||
|
|
assert_eq!(input.example1, Some(parse_quote!(test::path)));
|
||
|
|
assert_eq!(input.example2, "HELLO".to_string());
|
||
|
|
}
|