impl reviewer feedback

- remove unused (pun intentional) `continue`
- improve wording with assoc items in general

compiler/rustc_passes/src/dead.rs

@@ -700,6 +700,13 @@ impl<'tcx> DeadVisitor<'tcx> {
             .collect();
 
         let descr = tcx.def_descr(first_id.to_def_id());
+        // `impl` blocks are "batched" and (unlike other batching) might
+        // contain different kinds of associated items.
+        let descr = if dead_codes.iter().any(|did| tcx.def_descr(did.to_def_id()) != descr) {
+            "associated item"
+        } else {
+            descr
+        };
         let num = dead_codes.len();
         let multiple = num > 6;
         let name_list = names.into();
@@ -842,16 +849,9 @@ fn check_mod_deathness(tcx: TyCtxt<'_>, module: LocalDefId) {
         if let hir::ItemKind::Impl(impl_item) = tcx.hir().item(item).kind {
             let mut dead_items = Vec::new();
             for item in impl_item.items {
-                match item.kind {
+                let did = item.id.owner_id.def_id;
-                    hir::AssocItemKind::Const | hir::AssocItemKind::Type => {
+                if !visitor.is_live_code(did) {
-                        visitor.check_definition(item.id.owner_id.def_id)
+                    dead_items.push(did)
-                    }
-                    hir::AssocItemKind::Fn { .. } => {
-                        let did = item.id.owner_id.def_id;
-                        if !visitor.is_live_code(did) {
-                            dead_items.push(did)
-                        }
-                    }
                 }
             }
             visitor.warn_multiple_dead_codes(
@@ -860,7 +860,6 @@ fn check_mod_deathness(tcx: TyCtxt<'_>, module: LocalDefId) {
                 Some(item.owner_id.def_id),
                 false,
             );
-            continue;
         }
 
         if !live_symbols.contains(&item.owner_id.def_id) {

tests/ui/lint/dead-code/unused-assoc-fns.rs

@@ -1,19 +1,29 @@
+#![feature(inherent_associated_types)]
+#![allow(incomplete_features)]
 #![deny(unused)]
 
 struct Foo;
 
 impl Foo {
     fn one() {}
-    //~^ ERROR associated functions `one`, `two`, and `three` are never used [dead_code]
+    //~^ ERROR associated items `one`, `two`, `CONSTANT`, `Type`, and `three` are never used [dead_code]
 
     fn two(&self) {}
 
-    // seperation between functions
+    // seperation between items
     // ...
     // ...
 
     fn used() {}
 
+    const CONSTANT: usize = 5;
+
+    // more seperation
+    // ...
+    // ...
+
+    type Type = usize;
+
     fn three(&self) {
         Foo::one();
         // ...

tests/ui/lint/dead-code/unused-assoc-fns.stderr

@@ -1,19 +1,25 @@
-error: associated functions `one`, `two`, and `three` are never used
+error: associated items `one`, `two`, `CONSTANT`, `Type`, and `three` are never used
-  --> $DIR/unused-assoc-fns.rs:6:8
+  --> $DIR/unused-assoc-fns.rs:8:8
    |
 LL | impl Foo {
-   | -------- associated functions in this implementation
+   | -------- associated items in this implementation
 LL |     fn one() {}
    |        ^^^
 ...
 LL |     fn two(&self) {}
    |        ^^^
 ...
+LL |     const CONSTANT: usize = 5;
+   |           ^^^^^^^^
+...
+LL |     type Type = usize;
+   |          ^^^^
+LL |
 LL |     fn three(&self) {
    |        ^^^^^
    |
 note: the lint level is defined here
-  --> $DIR/unused-assoc-fns.rs:1:9
+  --> $DIR/unused-assoc-fns.rs:3:9
    |
 LL | #![deny(unused)]
    |         ^^^^^^