Rollup merge of rust-lang#98844 - cjgillot:deep-visit, r=jyn514

Reword comments and rename HIR visiting methods.

Sparked by this discussion in [zulip](https://rust-lang.zulipchat.com/#narrow/stream/182449-t-compiler.2Fhelp/topic/Confused.20by.20comment.20on.20.60deep_visit_item_likes_in_module.60)

r? ``@jyn514`` ``@camsteffen``

Author: matthiaskrgr

compiler/rustc_hir/src/intravisit.rs

@@ -19,7 +19,7 @@
 //!    - Example: Examine each expression to look for its type and do some check or other.
 //!    - How: Implement `intravisit::Visitor` and override the `NestedFilter` type to
 //!      `nested_filter::OnlyBodies` (and implement `nested_visit_map`), and use
-//!      `tcx.hir().deep_visit_all_item_likes(&mut visitor)`. Within your
+//!      `tcx.hir().visit_all_item_likes_in_crate(&mut visitor)`. Within your
 //!      `intravisit::Visitor` impl, implement methods like `visit_expr()` (don't forget to invoke
 //!      `intravisit::walk_expr()` to keep walking the subparts).
 //!    - Pro: Visitor methods for any kind of HIR node, not just item-like things.
@@ -190,7 +190,7 @@ use nested_filter::NestedFilter;
 /// (this is why the module is called `intravisit`, to distinguish it
 /// from the AST's `visit` module, which acts differently). If you
 /// simply want to visit all items in the crate in some order, you
-/// should call `Crate::visit_all_items`. Otherwise, see the comment
+/// should call `tcx.hir().visit_all_item_likes_in_crate`. Otherwise, see the comment
 /// on `visit_nested_item` for details on how to visit nested items.
 ///
 /// If you want to ensure that your code handles every variant

compiler/rustc_incremental/src/assert_dep_graph.rs

@@ -75,7 +75,7 @@ pub fn assert_dep_graph(tcx: TyCtxt<'_>) {
             let mut visitor =
                 IfThisChanged { tcx, if_this_changed: vec![], then_this_would_need: vec![] };
             visitor.process_attrs(hir::CRATE_HIR_ID);
-            tcx.hir().deep_visit_all_item_likes(&mut visitor);
+            tcx.hir().visit_all_item_likes_in_crate(&mut visitor);
             (visitor.if_this_changed, visitor.then_this_would_need)
         };
 

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -419,7 +419,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             return;
         }
 
-        self.tcx.hir().deep_visit_all_item_likes(self);
+        self.tcx.hir().visit_all_item_likes_in_crate(self);
     }
 
     fn encode_def_path_table(&mut self) {

compiler/rustc_middle/src/hir/map/mod.rs

@@ -568,7 +568,7 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    /// Walks the contents of a crate. See also `Crate::visit_all_items`.
+    /// Walks the contents of the local crate. See also `visit_all_item_likes_in_crate`.
     pub fn walk_toplevel_module(self, visitor: &mut impl Visitor<'hir>) {
         let (top_mod, span, hir_id) = self.get_module(CRATE_DEF_ID);
         visitor.visit_mod(top_mod, span, hir_id);
@@ -588,53 +588,61 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    /// Visits all items in the crate in some deterministic (but
-    /// unspecified) order. If you need to process every item,
-    /// and care about nesting -- usually because your algorithm
-    /// follows lexical scoping rules -- then this method is the best choice.
-    /// If you don't care about nesting, you should use the `tcx.hir_crate_items()` query
-    /// or `items()` instead.
+    /// Visits all item-likes in the crate in some deterministic (but unspecified) order. If you
+    /// need to process every item-like, and don't care about visiting nested items in a particular
+    /// order then this method is the best choice.  If you do care about this nesting, you should
+    /// use the `tcx.hir().walk_toplevel_module`.
+    ///
+    /// Note that this function will access HIR for all the item-likes in the crate.  If you only
+    /// need to access some of them, it is usually better to manually loop on the iterators
+    /// provided by `tcx.hir_crate_items(())`.
     ///
     /// Please see the notes in `intravisit.rs` for more information.
-    pub fn deep_visit_all_item_likes<V>(self, visitor: &mut V)
+    pub fn visit_all_item_likes_in_crate<V>(self, visitor: &mut V)
     where
         V: Visitor<'hir>,
     {
-        let krate = self.krate();
-        for owner in krate.owners.iter().filter_map(|i| i.as_owner()) {
-            match owner.node() {
-                OwnerNode::Item(item) => visitor.visit_item(item),
-                OwnerNode::ForeignItem(item) => visitor.visit_foreign_item(item),
-                OwnerNode::ImplItem(item) => visitor.visit_impl_item(item),
-                OwnerNode::TraitItem(item) => visitor.visit_trait_item(item),
-                OwnerNode::Crate(_) => {}
-            }
+        let krate = self.tcx.hir_crate_items(());
+
+        for id in krate.items() {
+            visitor.visit_item(self.item(id));
+        }
+
+        for id in krate.trait_items() {
+            visitor.visit_trait_item(self.trait_item(id));
+        }
+
+        for id in krate.impl_items() {
+            visitor.visit_impl_item(self.impl_item(id));
+        }
+
+        for id in krate.foreign_items() {
+            visitor.visit_foreign_item(self.foreign_item(id));
         }
     }
 
-    /// If you don't care about nesting, you should use the
-    /// `tcx.hir_module_items()` query or `module_items()` instead.
-    /// Please see notes in `deep_visit_all_item_likes`.
-    pub fn deep_visit_item_likes_in_module<V>(self, module: LocalDefId, visitor: &mut V)
+    /// This method is the equivalent of `visit_all_item_likes_in_crate` but restricted to
+    /// item-likes in a single module.
+    pub fn visit_item_likes_in_module<V>(self, module: LocalDefId, visitor: &mut V)
     where
         V: Visitor<'hir>,
     {
         let module = self.tcx.hir_module_items(module);
 
-        for id in module.items.iter() {
-            visitor.visit_item(self.item(*id));
+        for id in module.items() {
+            visitor.visit_item(self.item(id));
         }
 
-        for id in module.trait_items.iter() {
-            visitor.visit_trait_item(self.trait_item(*id));
+        for id in module.trait_items() {
+            visitor.visit_trait_item(self.trait_item(id));
         }
 
-        for id in module.impl_items.iter() {
-            visitor.visit_impl_item(self.impl_item(*id));
+        for id in module.impl_items() {
+            visitor.visit_impl_item(self.impl_item(id));
         }
 
-        for id in module.foreign_items.iter() {
-            visitor.visit_foreign_item(self.foreign_item(*id));
+        for id in module.foreign_items() {
+            visitor.visit_foreign_item(self.foreign_item(id));
         }
     }
 

compiler/rustc_middle/src/hir/nested_filter.rs

@@ -8,7 +8,7 @@ use rustc_hir::intravisit::nested_filter::NestedFilter;
 /// constant arguments of types, e.g. in `let _: [(); /* HERE */];`.
 ///
 /// **This is the most common choice.** A very common pattern is
-/// to use `deep_visit_all_item_likes()` as an outer loop,
+/// to use `visit_all_item_likes_in_crate()` as an outer loop,
 /// and to have the visitor that visits the contents of each item
 /// using this setting.
 pub struct OnlyBodies(());

compiler/rustc_mir_transform/src/lib.rs

@@ -173,7 +173,7 @@ fn mir_keys(tcx: TyCtxt<'_>, (): ()) -> FxIndexSet<LocalDefId> {
             intravisit::walk_struct_def(self, v)
         }
     }
-    tcx.hir().deep_visit_all_item_likes(&mut GatherCtors { tcx, set: &mut set });
+    tcx.hir().visit_all_item_likes_in_crate(&mut GatherCtors { tcx, set: &mut set });
 
     set
 }

compiler/rustc_passes/src/check_attr.rs

@@ -2428,7 +2428,7 @@ fn check_non_exported_macro_for_invalid_attrs(tcx: TyCtxt<'_>, item: &Item<'_>)
 
 fn check_mod_attrs(tcx: TyCtxt<'_>, module_def_id: LocalDefId) {
     let check_attr_visitor = &mut CheckAttrVisitor { tcx };
-    tcx.hir().deep_visit_item_likes_in_module(module_def_id, check_attr_visitor);
+    tcx.hir().visit_item_likes_in_module(module_def_id, check_attr_visitor);
     if module_def_id.is_top_level_module() {
         check_attr_visitor.check_attributes(CRATE_HIR_ID, DUMMY_SP, Target::Mod, None);
         check_invalid_crate_level_attr(tcx, tcx.hir().krate_attrs());

compiler/rustc_passes/src/check_const.rs

@@ -56,7 +56,7 @@ impl NonConstExpr {
 
 fn check_mod_const_bodies(tcx: TyCtxt<'_>, module_def_id: LocalDefId) {
     let mut vis = CheckConstVisitor::new(tcx);
-    tcx.hir().deep_visit_item_likes_in_module(module_def_id, &mut vis);
+    tcx.hir().visit_item_likes_in_module(module_def_id, &mut vis);
 }
 
 pub(crate) fn provide(providers: &mut Providers) {

compiler/rustc_passes/src/hir_id_validator.rs

@@ -28,7 +28,7 @@ pub fn check_crate(tcx: TyCtxt<'_>) {
                 errors: &errors,
             };
 
-            tcx.hir().deep_visit_item_likes_in_module(module_id, &mut v);
+            tcx.hir().visit_item_likes_in_module(module_id, &mut v);
         });
 
         let errors = errors.into_inner();

compiler/rustc_passes/src/liveness.rs

@@ -140,7 +140,7 @@ fn live_node_kind_to_string(lnk: LiveNodeKind, tcx: TyCtxt<'_>) -> String {
 }
 
 fn check_mod_liveness(tcx: TyCtxt<'_>, module_def_id: LocalDefId) {
-    tcx.hir().deep_visit_item_likes_in_module(module_def_id, &mut IrMaps::new(tcx));
+    tcx.hir().visit_item_likes_in_module(module_def_id, &mut IrMaps::new(tcx));
 }
 
 pub fn provide(providers: &mut Providers) {