fallout from separating impl-items from impls

Basically adding `visit_impl_item` in various places and so forth.

Author: nikomatsakis

src/librustc/hir/itemlikevisit.rs

@@ -56,6 +56,7 @@ use super::intravisit::Visitor;
 /// needed.
 pub trait ItemLikeVisitor<'hir> {
     fn visit_item(&mut self, item: &'hir Item);
+    fn visit_impl_item(&mut self, impl_item: &'hir ImplItem);
 }
 
 pub struct DeepVisitor<'v, V: 'v> {
@@ -76,4 +77,8 @@ impl<'v, 'hir, V> ItemLikeVisitor<'hir> for DeepVisitor<'v, V>
     fn visit_item(&mut self, item: &'hir Item) {
         self.visitor.visit_item(item);
     }
+
+    fn visit_impl_item(&mut self, impl_item: &'hir ImplItem) {
+        self.visitor.visit_impl_item(impl_item);
+    }
 }

src/librustc/hir/map/collector.rs

@@ -99,6 +99,10 @@ impl<'ast> Visitor<'ast> for NodeCollector<'ast> {
         }
     }
 
+    fn visit_nested_impl_item(&mut self, item_id: ImplItemId) {
+        self.visit_impl_item(self.krate.impl_item(item_id))
+    }
+
     fn visit_item(&mut self, i: &'ast Item) {
         debug!("visit_item: {:?}", i);
 

src/librustc/lint/context.rs

@@ -797,8 +797,13 @@ impl<'a, 'tcx, 'v> hir_visit::Visitor<'v> for LateContext<'a, 'tcx> {
     /// items in the context of the outer item, so enable
     /// deep-walking.
     fn visit_nested_item(&mut self, item: hir::ItemId) {
-        let tcx = self.tcx;
-        self.visit_item(tcx.map.expect_item(item.id))
+        let item = self.tcx.map.expect_item(item.id);
+        self.visit_item(item)
+    }
+
+    fn visit_nested_impl_item(&mut self, item_id: hir::ImplItemId) {
+        let impl_item = self.tcx.map.impl_item(item_id);
+        self.visit_impl_item(impl_item)
     }
 
     fn visit_item(&mut self, it: &hir::Item) {

src/librustc/middle/dead.rs

@@ -330,11 +330,12 @@ fn has_allow_dead_code_or_lang_attr(attrs: &[ast::Attribute]) -> bool {
 //   or
 //   2) We are not sure to be live or not
 //     * Implementation of a trait method
-struct LifeSeeder {
-    worklist: Vec<ast::NodeId>
+struct LifeSeeder<'k> {
+    worklist: Vec<ast::NodeId>,
+    krate: &'k hir::Crate,
 }
 
-impl<'v> ItemLikeVisitor<'v> for LifeSeeder {
+impl<'v, 'k> ItemLikeVisitor<'v> for LifeSeeder<'k> {
     fn visit_item(&mut self, item: &hir::Item) {
         let allow_dead_code = has_allow_dead_code_or_lang_attr(&item.attrs);
         if allow_dead_code {
@@ -358,17 +359,22 @@ impl<'v> ItemLikeVisitor<'v> for LifeSeeder {
                     }
                 }
             }
-            hir::ItemImpl(.., ref opt_trait, _, ref impl_items) => {
-                for impl_item in impl_items {
+            hir::ItemImpl(.., ref opt_trait, _, ref impl_item_ids) => {
+                for &impl_item_id in impl_item_ids {
+                    let impl_item = self.krate.impl_item(impl_item_id);
                     if opt_trait.is_some() ||
                             has_allow_dead_code_or_lang_attr(&impl_item.attrs) {
-                        self.worklist.push(impl_item.id);
+                        self.worklist.push(impl_item_id.id);
                     }
                 }
             }
             _ => ()
         }
     }
+
+    fn visit_impl_item(&mut self, _item: &hir::ImplItem) {
+        // ignore: we are handling this in `visit_item` above
+    }
 }
 
 fn create_and_seed_worklist<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
@@ -387,7 +393,8 @@ fn create_and_seed_worklist<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
     // Seed implemented trait items
     let mut life_seeder = LifeSeeder {
-        worklist: worklist
+        worklist: worklist,
+        krate: krate,
     };
     krate.visit_all_item_likes(&mut life_seeder);
 
@@ -510,8 +517,13 @@ impl<'a, 'tcx, 'v> Visitor<'v> for DeadVisitor<'a, 'tcx> {
     /// an error. We could do this also by checking the parents, but
     /// this is how the code is setup and it seems harmless enough.
     fn visit_nested_item(&mut self, item: hir::ItemId) {
-        let tcx = self.tcx;
-        self.visit_item(tcx.map.expect_item(item.id))
+        let item = self.tcx.map.expect_item(item.id);
+        self.visit_item(item)
+    }
+
+    fn visit_nested_impl_item(&mut self, item_id: hir::ImplItemId) {
+        let impl_item = self.tcx.map.impl_item(item_id);
+        self.visit_impl_item(impl_item)
     }
 
     fn visit_item(&mut self, item: &hir::Item) {

src/librustc/middle/entry.rs

@@ -17,7 +17,7 @@ use syntax::ast::NodeId;
 use syntax::attr;
 use syntax::entry::EntryPointType;
 use syntax_pos::Span;
-use hir::{Item, ItemFn};
+use hir::{Item, ItemFn, ImplItem};
 use hir::itemlikevisit::ItemLikeVisitor;
 
 struct EntryContext<'a, 'tcx: 'a> {
@@ -46,6 +46,10 @@ impl<'a, 'tcx> ItemLikeVisitor<'tcx> for EntryContext<'a, 'tcx> {
         let at_root = def_key.parent == Some(CRATE_DEF_INDEX);
         find_item(item, self, at_root);
     }
+
+    fn visit_impl_item(&mut self, _impl_item: &'tcx ImplItem) {
+        // entry fn is never an impl item
+    }
 }
 
 pub fn find_entry_point(session: &Session, ast_map: &ast_map::Map) {

src/librustc/middle/lang_items.rs

@@ -164,6 +164,10 @@ impl<'a, 'v, 'tcx> ItemLikeVisitor<'v> for LanguageItemCollector<'a, 'tcx> {
             }
         }
     }
+
+    fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
+        // at present, lang items are always items, not impl items
+    }
 }
 
 impl<'a, 'tcx> LanguageItemCollector<'a, 'tcx> {

src/librustc/middle/reachable.rs

@@ -336,6 +336,10 @@ impl<'a, 'v> ItemLikeVisitor<'v> for CollectPrivateImplItemsVisitor<'a> {
             }
         }
     }
+
+    fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
+        // processed in visit_item above
+    }
 }
 
 pub fn find_reachable<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,

src/librustc/middle/resolve_lifetime.rs

@@ -141,6 +141,11 @@ impl<'a, 'tcx, 'v> Visitor<'v> for LifetimeContext<'a, 'tcx> {
         self.visit_item(item)
     }
 
+    fn visit_nested_impl_item(&mut self, id: hir::ImplItemId) {
+        let impl_item = self.hir_map.impl_item(id);
+        self.visit_impl_item(impl_item)
+    }
+
     fn visit_item(&mut self, item: &hir::Item) {
         // Save labels for nested items.
         let saved_labels_in_fn = replace(&mut self.labels_in_fn, vec![]);

src/librustc/middle/stability.rs

@@ -239,8 +239,13 @@ impl<'a, 'tcx, 'v> Visitor<'v> for Annotator<'a, 'tcx> {
     /// nested items in the context of the outer item, so enable
     /// deep-walking.
     fn visit_nested_item(&mut self, item: hir::ItemId) {
-        let tcx = self.tcx;
-        self.visit_item(tcx.map.expect_item(item.id))
+        let item = self.tcx.map.expect_item(item.id);
+        self.visit_item(item)
+    }
+
+    fn visit_nested_impl_item(&mut self, item_id: hir::ImplItemId) {
+        let impl_item = self.tcx.map.impl_item(item_id);
+        self.visit_impl_item(impl_item)
     }
 
     fn visit_item(&mut self, i: &Item) {
@@ -449,8 +454,13 @@ impl<'a, 'v, 'tcx> Visitor<'v> for Checker<'a, 'tcx> {
     /// nested items in the context of the outer item, so enable
     /// deep-walking.
     fn visit_nested_item(&mut self, item: hir::ItemId) {
-        let tcx = self.tcx;
-        self.visit_item(tcx.map.expect_item(item.id))
+        let item = self.tcx.map.expect_item(item.id);
+        self.visit_item(item)
+    }
+
+    fn visit_nested_impl_item(&mut self, item_id: hir::ImplItemId) {
+        let impl_item = self.tcx.map.impl_item(item_id);
+        self.visit_impl_item(impl_item)
     }
 
     fn visit_item(&mut self, item: &hir::Item) {
@@ -527,9 +537,10 @@ pub fn check_item<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         // For implementations of traits, check the stability of each item
         // individually as it's possible to have a stable trait with unstable
         // items.
-        hir::ItemImpl(.., Some(ref t), _, ref impl_items) => {
+        hir::ItemImpl(.., Some(ref t), _, ref impl_item_ids) => {
             let trait_did = tcx.expect_def(t.ref_id).def_id();
-            for impl_item in impl_items {
+            for &impl_item_id in impl_item_ids {
+                let impl_item = tcx.map.impl_item(impl_item_id);
                 let item = tcx.associated_items(trait_did)
                     .find(|item| item.name == impl_item.name).unwrap();
                 if warn_about_defns {

src/librustc_driver/derive_registrar.rs

@@ -34,4 +34,8 @@ impl<'v> ItemLikeVisitor<'v> for Finder {
             self.registrar = Some(item.id);
         }
     }
+
+    fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
+    }
 }
+