Rollup merge of rust-lang#35355 - shri3k:E0046, r=jonathandturner

Updates compiler error E0046 with new format Addresses rust-lang#35209 as part of rust-lang#35233. r? @jonathandturner I've repeated the following in my code. If this is something not desirable then let me know if there's any process to make this any cleaner. Thank you. ```rust missing_items.iter() .map(|name| name.to_string()) .collect::<Vec<_>>().join("`, `")) ```

Author: Jonathan Turner

src/librustc_typeck/check/mod.rs

@@ -1136,11 +1136,16 @@ fn check_impl_items_against_trait<'a, 'tcx>(ccx: &CrateCtxt<'a, 'tcx>,
  }
 
  if !missing_items.is_empty() {
- span_err!(tcx.sess, impl_span, E0046,
+ struct_span_err!(tcx.sess, impl_span, E0046,
  "not all trait items implemented, missing: `{}`",
  missing_items.iter()
  .map(|name| name.to_string())
  .collect::<Vec<_>>().join("`, `"))
+ .span_label(impl_span, &format!("missing `{}` in implementation",
+ missing_items.iter()
+ .map(|name| name.to_string())
+ .collect::<Vec<_>>().join("`, `"))
+ ).emit();
  }
 
  if !invalidated_items.is_empty() {

src/test/compile-fail/E0046.rs

@@ -14,7 +14,9 @@ trait Foo {
 
 struct Bar;
 
-impl Foo for Bar {} //~ ERROR E0046
+impl Foo for Bar {}
+//~^ ERROR E0046
+//~| NOTE missing `foo` in implementation
 
 fn main() {
 }

src/test/compile-fail/impl-wrong-item-for-trait.rs

@@ -21,6 +21,7 @@ pub struct FooConstForMethod;
 
 impl Foo for FooConstForMethod {
  //~^ ERROR E0046
+ //~| NOTE missing `bar` in implementation
  const bar: u64 = 1;
  //~^ ERROR E0323
  //~| NOTE does not match trait
@@ -31,6 +32,7 @@ pub struct FooMethodForConst;
 
 impl Foo for FooMethodForConst {
  //~^ ERROR E0046
+ //~| NOTE missing `MY_CONST` in implementation
  fn bar(&self) {}
  fn MY_CONST() {}
  //~^ ERROR E0324
@@ -41,6 +43,7 @@ pub struct FooTypeForMethod;
 
 impl Foo for FooTypeForMethod {
  //~^ ERROR E0046
+ //~| NOTE missing `bar` in implementation
  type bar = u64;
  //~^ ERROR E0325
  //~| NOTE does not match trait

src/test/compile-fail/issue-23729.rs

@@ -18,7 +18,8 @@ fn main() {
  }
 
  impl Iterator for Recurrence {
- //~^ ERROR not all trait items implemented, missing: `Item` [E0046]
+ //~^ ERROR E0046
+ //~| NOTE missing `Item` in implementation
  #[inline]
  fn next(&mut self) -> Option<u64> {
  if self.pos < 2 {

src/test/compile-fail/issue-23827.rs

@@ -34,7 +34,8 @@ impl<C: Component> FnMut<(C,)> for Prototype {
 }
 
 impl<C: Component> FnOnce<(C,)> for Prototype {
- //~^ ERROR not all trait items implemented, missing: `Output` [E0046]
+ //~^ ERROR E0046
+ //~| NOTE missing `Output` in implementation
  extern "rust-call" fn call_once(self, (comp,): (C,)) -> Prototype {
  Fn::call(&self, (comp,))
  }

src/test/compile-fail/issue-24356.rs

@@ -28,7 +28,8 @@ fn main() {
 
  // Causes ICE
  impl Deref for Thing {
- //~^ ERROR not all trait items implemented, missing: `Target` [E0046]
+ //~^ ERROR E0046
+ //~| NOTE missing `Target` in implementation
  fn deref(&self) -> i8 { self.0 }
  }