error_snippet_derive/
lib.rs

1use diagnostic::Diagnostic;
2use quote::quote;
3use syn::{parse_macro_input, DeriveInput};
4
5mod args;
6mod diagnostic;
7mod fields;
8mod fmt;
9mod tokens;
10
11#[proc_macro_derive(
12    Diagnostic,
13    attributes(diagnostic, span, label, related, cause, causes)
14)]
15pub fn derive_diagnostic(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
16    let input = parse_macro_input!(input as DeriveInput);
17    let cmd = match Diagnostic::from(input) {
18        Ok(cmd) => cmd.tokens().unwrap_or_else(|err| err.to_compile_error()),
19        Err(err) => return err.to_compile_error().into(),
20    };
21
22    quote!(#cmd).into()
23}