Skip to main content

rustc_attr_parsing/attributes/diagnostic/
do_not_recommend.rs

1use rustc_feature::{AttributeTemplate, template};
2use rustc_hir::attrs::AttributeKind;
3use rustc_hir::lints::AttributeLintKind;
4use rustc_session::lint::builtin::MALFORMED_DIAGNOSTIC_ATTRIBUTES;
5use rustc_span::{Symbol, sym};
6
7use crate::attributes::{OnDuplicate, SingleAttributeParser};
8use crate::context::{AcceptContext, Stage};
9use crate::parser::ArgParser;
10use crate::target_checking::{ALL_TARGETS, AllowedTargets};
11
12pub(crate) struct DoNotRecommendParser;
13impl<S: Stage> SingleAttributeParser<S> for DoNotRecommendParser {
14    const PATH: &[Symbol] = &[sym::diagnostic, sym::do_not_recommend];
15    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Warn;
16    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(ALL_TARGETS); // Checked in check_attr.
17    const TEMPLATE: AttributeTemplate = ::rustc_feature::AttributeTemplate {
    word: true,
    list: None,
    one_of: &[],
    name_value_str: None,
    docs: None,
}template!(Word /*doesn't matter */);
18
19    fn convert(cx: &mut AcceptContext<'_, '_, S>, args: &ArgParser) -> Option<AttributeKind> {
20        let attr_span = cx.attr_span;
21        if !#[allow(non_exhaustive_omitted_patterns)] match args {
    ArgParser::NoArgs => true,
    _ => false,
}matches!(args, ArgParser::NoArgs) {
22            cx.emit_lint(
23                MALFORMED_DIAGNOSTIC_ATTRIBUTES,
24                AttributeLintKind::DoNotRecommendDoesNotExpectArgs,
25                attr_span,
26            );
27        }
28        Some(AttributeKind::DoNotRecommend { attr_span })
29    }
30}