Remove AttributeLintKind::DuplicateDocAlias variant

Author: GuillaumeGomez

compiler/rustc_attr_parsing/src/attributes/doc.rs

@@ -255,9 +255,11 @@ impl DocParser {
         }
 
         if let Some(first_definition) = self.attribute.aliases.get(&alias).copied() {
-            cx.emit_lint(
+            cx.emit_dyn_lint(
                 rustc_session::lint::builtin::UNUSED_ATTRIBUTES,
-                AttributeLintKind::DuplicateDocAlias { first_definition },
+                move |dcx, level| {
+                    crate::errors::DocAliasDuplicated { first_definition }.into_diag(dcx, level)
+                },
                 span,
             );
         }

compiler/rustc_attr_parsing/src/errors.rs

@@ -166,3 +166,10 @@ pub(crate) struct InvalidAttrStyle<'a> {
     pub target_span: Option<Span>,
     pub target: &'static str,
 }
+
+#[derive(Diagnostic)]
+#[diag("doc alias is duplicated")]
+pub(crate) struct DocAliasDuplicated {
+    #[label("first defined here")]
+    pub first_definition: Span,
+}

compiler/rustc_lint/src/early/diagnostics.rs

@@ -42,9 +42,6 @@ impl<'a> Diagnostic<'a, ()> for DecorateAttrLint<'_, '_, '_> {
                 check_cfg::unexpected_cfg_value(self.sess, self.tcx, name, value)
                     .into_diag(dcx, level)
             }
-            &AttributeLintKind::DuplicateDocAlias { first_definition } => {
-                lints::DocAliasDuplicated { first_defn: first_definition }.into_diag(dcx, level)
-            }
 
             &AttributeLintKind::DocAutoCfgExpectsHideOrShow => {
                 lints::DocAutoCfgExpectsHideOrShow.into_diag(dcx, level)

compiler/rustc_lint/src/lints.rs

@@ -3303,13 +3303,6 @@ pub(crate) struct ExpectedNoArgs;
 )]
 pub(crate) struct ExpectedNameValue;
 
-#[derive(Diagnostic)]
-#[diag("doc alias is duplicated")]
-pub(crate) struct DocAliasDuplicated {
-    #[label("first defined here")]
-    pub first_defn: Span,
-}
-
 #[derive(Diagnostic)]
 #[diag("only `hide` or `show` are allowed in `#[doc(auto_cfg(...))]`")]
 pub(crate) struct DocAutoCfgExpectsHideOrShow;

compiler/rustc_lint_defs/src/lib.rs

@@ -656,7 +656,6 @@ pub enum DeprecatedSinceKind {
 pub enum AttributeLintKind {
     UnexpectedCfgName((Symbol, Span), Option<(Symbol, Span)>),
     UnexpectedCfgValue((Symbol, Span), Option<(Symbol, Span)>),
-    DuplicateDocAlias { first_definition: Span },
     DocAutoCfgExpectsHideOrShow,
     DocAutoCfgHideShowUnexpectedItem { attr_name: Symbol },
     DocAutoCfgHideShowExpectsList { attr_name: Symbol },