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//! In case of bad input, parsing should fail. The error should have locations set in derived implementations.
// The use of fields in debug print commands does not count as "used",
// which causes the fields to trigger an unwanted dead code warning.
#![allow(dead_code)]
use darling::{FromDeriveInput, FromMeta};
use syn::parse_quote;
#[derive(Debug, FromMeta)]
struct Dolor {
#[darling(rename = "amet")]
sit: bool,
world: bool,
}
#[derive(Debug, FromDeriveInput)]
#[darling(from_ident, attributes(hello))]
struct Lorem {
ident: syn::Ident,
ipsum: Dolor,
}
impl From<syn::Ident> for Lorem {
fn from(ident: syn::Ident) -> Self {
Lorem {
ident,
ipsum: Dolor {
sit: false,
world: true,
},
}
}
}
#[test]
fn parsing_fail() {
let di = parse_quote! {
#[hello(ipsum(amet = "yes", world = false))]
pub struct Foo;
};
println!("{}", Lorem::from_derive_input(&di).unwrap_err());
}
#[test]
fn missing_field() {
let di = parse_quote! {
#[hello(ipsum(amet = true))]
pub struct Foo;
};
println!("{}", Lorem::from_derive_input(&di).unwrap_err());
}