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use darling::FromDeriveInput;
use syn::{parse_quote, Ident, LitStr, Path};
#[derive(Debug, FromDeriveInput)]
#[darling(supports(struct_unit), attributes(bar))]
pub struct Bar {
pub ident: Ident,
pub st: Path,
pub file: LitStr,
}
/// attribute which isn't a valid meta gets an error.
/// Properties can be split across multiple attributes; this test ensures that one
/// non-meta attribute does not interfere with the parsing of other, well-formed attributes.
#[test]
fn non_meta_attribute_does_not_block_others() {
let di = parse_quote! {
#[derive(Bar)]
#[bar(st = RocketEngine: Debug)]
#[bar(file = "motors/example_6.csv")]
pub struct EstesC6;
};
let errors: darling::Error = Bar::from_derive_input(&di).unwrap_err().flatten();
// The number of errors here is 2:
// - The parsing error caused by a where-clause body where it doesn't belong
// - The missing `st` value because the parsing failure blocked that attribute from
// being read.
assert_eq!(2, errors.len());
}