rustc_attr_parsing/attributes/diagnostic/
on_unmatched_args.rs1use rustc_feature::AttributeStability;
2use rustc_hir::attrs::diagnostic::Directive;
3use rustc_session::lint::builtin::MISPLACED_DIAGNOSTIC_ATTRIBUTES;
4
5use crate::attributes::diagnostic::*;
6use crate::attributes::prelude::*;
7use crate::diagnostics::DiagnosticOnUnmatchedArgsOnlyForMacros;
8
9#[derive(#[automatically_derived]
impl ::core::default::Default for OnUnmatchedArgsParser {
#[inline]
fn default() -> OnUnmatchedArgsParser {
OnUnmatchedArgsParser {
span: ::core::default::Default::default(),
directive: ::core::default::Default::default(),
}
}
}Default)]
10pub(crate) struct OnUnmatchedArgsParser {
11 span: Option<Span>,
12 directive: Option<(Span, Directive)>,
13}
14
15impl AttributeParser for OnUnmatchedArgsParser {
16 const ATTRIBUTES: AcceptMapping<Self> = &[(
17 &[sym::diagnostic, sym::on_unmatched_args],
18 crate::AttributeTemplate {
word: false,
list: Some(&[r#"/*opt*/ message = "...", /*opt*/ label = "...", /*opt*/ note = "...""#]),
one_of: &[],
name_value_str: None,
docs: None,
}template!(List: &[r#"/*opt*/ message = "...", /*opt*/ label = "...", /*opt*/ note = "...""#]),
19 AttributeStability::Stable, |this, cx, args| {
21 if !cx.features().diagnostic_on_unmatched_args() {
22 return;
23 }
24
25 let span = cx.attr_span;
26 this.span = Some(span);
27
28 if !#[allow(non_exhaustive_omitted_patterns)] match cx.target {
Target::MacroDef => true,
_ => false,
}matches!(cx.target, Target::MacroDef) {
29 cx.emit_lint(
30 MISPLACED_DIAGNOSTIC_ATTRIBUTES,
31 DiagnosticOnUnmatchedArgsOnlyForMacros,
32 span,
33 );
34 return;
35 }
36
37 let mode = Mode::DiagnosticOnUnmatchedArgs;
38 let Some(items) = parse_list(cx, args, mode) else { return };
39
40 let Some(directive) = parse_directive_items(cx, mode, items.mixed(), true) else {
41 return;
42 };
43 merge_directives(cx, &mut this.directive, (span, directive));
44 },
45 )];
46
47 const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(ALL_TARGETS);
48
49 fn finalize(self, _cx: &FinalizeContext<'_, '_>) -> Option<AttributeKind> {
50 if let Some(_span) = self.span {
51 Some(AttributeKind::OnUnmatchedArgs {
52 directive: self.directive.map(|d| Box::new(d.1)),
53 })
54 } else {
55 None
56 }
57 }
58}