rm higher-ranked lifetimes from DocVisitor

This allows the visitor to borrow from the visitees.

src/librustdoc/html/render/write_shared.rs

@@ -865,7 +865,7 @@ struct AliasedTypeImpl<'cache> {
     type_aliases: Vec<(&'cache [Symbol], Item)>,
 }
 
-impl<'cx, 'cache> DocVisitor for TypeImplCollector<'cx, 'cache> {
+impl<'cx, 'cache> DocVisitor<'_> for TypeImplCollector<'cx, 'cache> {
     fn visit_item(&mut self, it: &Item) {
         self.visit_item_recur(it);
         let cache = self.cache;

src/librustdoc/html/sources.rs

@@ -103,7 +103,7 @@ impl LocalSourcesCollector<'_, '_> {
     }
 }
 
-impl DocVisitor for LocalSourcesCollector<'_, '_> {
+impl DocVisitor<'_> for LocalSourcesCollector<'_, '_> {
     fn visit_item(&mut self, item: &clean::Item) {
         self.add_local_source(item);
 
@@ -122,7 +122,7 @@ struct SourceCollector<'a, 'tcx> {
     crate_name: &'a str,
 }
 
-impl DocVisitor for SourceCollector<'_, '_> {
+impl DocVisitor<'_> for SourceCollector<'_, '_> {
     fn visit_item(&mut self, item: &clean::Item) {
         if !self.cx.include_sources {
             return;

src/librustdoc/passes/calculate_doc_coverage.rs

@@ -187,7 +187,7 @@ impl<'a, 'b> CoverageCalculator<'a, 'b> {
     }
 }
 
-impl<'a, 'b> DocVisitor for CoverageCalculator<'a, 'b> {
+impl<'a, 'b> DocVisitor<'_> for CoverageCalculator<'a, 'b> {
     fn visit_item(&mut self, i: &clean::Item) {
         if !i.item_id.is_local() {
             // non-local items are skipped because they can be out of the users control,

src/librustdoc/passes/check_doc_test_visibility.rs

@@ -34,7 +34,7 @@ pub(crate) fn check_doc_test_visibility(krate: Crate, cx: &mut DocContext<'_>) -
     krate
 }
 
-impl<'a, 'tcx> DocVisitor for DocTestVisibilityLinter<'a, 'tcx> {
+impl<'a, 'tcx> DocVisitor<'_> for DocTestVisibilityLinter<'a, 'tcx> {
     fn visit_item(&mut self, item: &Item) {
         look_for_tests(self.cx, &item.doc_value(), item);
 

src/librustdoc/passes/collect_intra_doc_links.rs

@@ -816,7 +816,7 @@ fn is_derive_trait_collision<T>(ns: &PerNS<Result<Vec<(Res, T)>, ResolutionFailu
     }
 }
 
-impl<'a, 'tcx> DocVisitor for LinkCollector<'a, 'tcx> {
+impl<'a, 'tcx> DocVisitor<'_> for LinkCollector<'a, 'tcx> {
     fn visit_item(&mut self, item: &Item) {
         self.resolve_links(item);
         self.visit_item_recur(item)

src/librustdoc/passes/collect_trait_impls.rs

@@ -229,7 +229,7 @@ struct SyntheticImplCollector<'a, 'tcx> {
     impls: Vec<Item>,
 }
 
-impl<'a, 'tcx> DocVisitor for SyntheticImplCollector<'a, 'tcx> {
+impl<'a, 'tcx> DocVisitor<'_> for SyntheticImplCollector<'a, 'tcx> {
     fn visit_item(&mut self, i: &Item) {
         if i.is_struct() || i.is_enum() || i.is_union() {
             // FIXME(eddyb) is this `doc(hidden)` check needed?
@@ -256,7 +256,7 @@ impl<'cache> ItemAndAliasCollector<'cache> {
     }
 }
 
-impl<'cache> DocVisitor for ItemAndAliasCollector<'cache> {
+impl<'cache> DocVisitor<'_> for ItemAndAliasCollector<'cache> {
     fn visit_item(&mut self, i: &Item) {
         self.items.insert(i.item_id);
 

src/librustdoc/passes/lint.rs

@@ -25,7 +25,7 @@ pub(crate) fn run_lints(krate: Crate, cx: &mut DocContext<'_>) -> Crate {
     krate
 }
 
-impl<'a, 'tcx> DocVisitor for Linter<'a, 'tcx> {
+impl<'a, 'tcx> DocVisitor<'_> for Linter<'a, 'tcx> {
     fn visit_item(&mut self, item: &Item) {
         let Some(hir_id) = DocContext::as_local_hir_id(self.cx.tcx, item.item_id) else {
             // If non-local, no need to check anything.

src/librustdoc/visit.rs

@@ -1,12 +1,12 @@
 use crate::clean::*;
 
-pub(crate) trait DocVisitor: Sized {
-    fn visit_item(&mut self, item: &Item) {
+pub(crate) trait DocVisitor<'a>: Sized {
+    fn visit_item(&mut self, item: &'a Item) {
         self.visit_item_recur(item)
     }
 
     /// don't override!
-    fn visit_inner_recur(&mut self, kind: &ItemKind) {
+    fn visit_inner_recur(&mut self, kind: &'a ItemKind) {
         match kind {
             StrippedItem(..) => unreachable!(),
             ModuleItem(i) => {
@@ -47,18 +47,18 @@ pub(crate) trait DocVisitor: Sized {
     }
 
     /// don't override!
-    fn visit_item_recur(&mut self, item: &Item) {
+    fn visit_item_recur(&mut self, item: &'a Item) {
         match &item.kind {
             StrippedItem(i) => self.visit_inner_recur(&*i),
             _ => self.visit_inner_recur(&item.kind),
         }
     }
 
-    fn visit_mod(&mut self, m: &Module) {
+    fn visit_mod(&mut self, m: &'a Module) {
         m.items.iter().for_each(|i| self.visit_item(i))
     }
 
-    fn visit_crate(&mut self, c: &Crate) {
+    fn visit_crate(&mut self, c: &'a Crate) {
         self.visit_item(&c.module);
 
         for trait_ in c.external_traits.values() {