Auto merge of #87246 - rust-lang:placeholder-pretty, r=nikomatsakis

When pretty printing, name placeholders as bound regions

Split from #85499

When we see a placeholder that we are going to print, treat it as a bound var (and add it to a `for<...>`

6 files changed, 10 insertions, 10 deletions

diff --git a/src/test/ui/associated-types/hr-associated-type-projection-1.rs b/src/test/ui/associated-types/hr-associated-type-projection-1.rs
index 1270cd6706a..bad736b64c0 100644
--- a/src/test/ui/associated-types/hr-associated-type-projection-1.rs
+++ b/src/test/ui/associated-types/hr-associated-type-projection-1.rs
@@ -11,7 +11,7 @@ where
 }
 
 impl<T: Copy + std::ops::Deref> UnsafeCopy<'_, T> for T {
-    //~^ ERROR the trait bound `<T as UnsafeCopy<'b, T>>::Item: Deref` is not satisfied
+    //~^ ERROR the trait bound `for<'b> <T as UnsafeCopy<'b, T>>::Item: Deref` is not satisfied
     type Item = T;
     //~^ ERROR the trait bound `for<'b> <T as UnsafeCopy<'b, T>>::Item: Deref
 }
diff --git a/src/test/ui/associated-types/hr-associated-type-projection-1.stderr b/src/test/ui/associated-types/hr-associated-type-projection-1.stderr
index cf4ec0babfc..49fad4e1b1c 100644
--- a/src/test/ui/associated-types/hr-associated-type-projection-1.stderr
+++ b/src/test/ui/associated-types/hr-associated-type-projection-1.stderr
@@ -14,16 +14,16 @@ LL |     type Item = T;
              <&T as Deref>
              <&mut T as Deref>
 
-error[E0277]: the trait bound `<T as UnsafeCopy<'b, T>>::Item: Deref` is not satisfied
+error[E0277]: the trait bound `for<'b> <T as UnsafeCopy<'b, T>>::Item: Deref` is not satisfied
   --> $DIR/hr-associated-type-projection-1.rs:13:33
    |
 LL | impl<T: Copy + std::ops::Deref> UnsafeCopy<'_, T> for T {
-   |                                 ^^^^^^^^^^^^^^^^^ the trait `Deref` is not implemented for `<T as UnsafeCopy<'b, T>>::Item`
+   |                                 ^^^^^^^^^^^^^^^^^ the trait `for<'b> Deref` is not implemented for `<T as UnsafeCopy<'b, T>>::Item`
    |
 help: consider further restricting the associated type
    |
-LL | impl<T: Copy + std::ops::Deref> UnsafeCopy<'_, T> for T where <T as UnsafeCopy<'b, T>>::Item: Deref {
-   |                                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | impl<T: Copy + std::ops::Deref> UnsafeCopy<'_, T> for T where for<'b> <T as UnsafeCopy<'b, T>>::Item: Deref {
+   |                                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/closures/issue-41366.stderr b/src/test/ui/closures/issue-41366.stderr
index 72ef5b3b962..ffe0bce6f0f 100644
--- a/src/test/ui/closures/issue-41366.stderr
+++ b/src/test/ui/closures/issue-41366.stderr
@@ -5,7 +5,7 @@ LL |     (&|_| ()) as &dyn for<'x> Fn(<u32 as T<'x>>::V);
    |     ^^------^
    |     | |
    |     | found signature of `fn(u16) -> _`
-   |     expected signature of `fn(<u32 as T<'x>>::V) -> _`
+   |     expected signature of `for<'x> fn(<u32 as T<'x>>::V) -> _`
    |
    = note: required for the cast to the object type `dyn for<'x> Fn(<u32 as T<'x>>::V)`
 
diff --git a/src/test/ui/coherence/coherence-fn-covariant-bound-vs-static.stderr b/src/test/ui/coherence/coherence-fn-covariant-bound-vs-static.stderr
index 7dabd97b94e..cfcef9699f3 100644
--- a/src/test/ui/coherence/coherence-fn-covariant-bound-vs-static.stderr
+++ b/src/test/ui/coherence/coherence-fn-covariant-bound-vs-static.stderr
@@ -1,10 +1,10 @@
-error[E0119]: conflicting implementations of trait `Trait` for type `for<'r> fn(fn(&'r ()))`
+error[E0119]: conflicting implementations of trait `Trait` for type `for<'r> fn(for<'r> fn(&'r ()))`
   --> $DIR/coherence-fn-covariant-bound-vs-static.rs:17:1
    |
 LL | impl Trait for for<'r> fn(fn(&'r ())) {}
    | ------------------------------------- first implementation here
 LL | impl<'a> Trait for fn(fn(&'a ())) {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `for<'r> fn(fn(&'r ()))`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `for<'r> fn(for<'r> fn(&'r ()))`
    |
    = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
 
diff --git a/src/test/ui/issues/issue-43623.stderr b/src/test/ui/issues/issue-43623.stderr
index 80aca482b3d..4bc5eb03e92 100644
--- a/src/test/ui/issues/issue-43623.stderr
+++ b/src/test/ui/issues/issue-43623.stderr
@@ -10,7 +10,7 @@ LL | {
 LL |     break_me::<Type, fn(_)>;
    |     ^^^^^^^^^^^^^^^^^^^^^^^
    |     |
-   |     expected signature of `fn(<Type as Trait<'b>>::Assoc) -> _`
+   |     expected signature of `for<'b> fn(<Type as Trait<'b>>::Assoc) -> _`
    |     found signature of `fn(()) -> _`
 
 error: aborting due to previous error
diff --git a/src/test/ui/issues/issue-60283.stderr b/src/test/ui/issues/issue-60283.stderr
index 650570b6471..149562f8fb3 100644
--- a/src/test/ui/issues/issue-60283.stderr
+++ b/src/test/ui/issues/issue-60283.stderr
@@ -10,7 +10,7 @@ LL |     F: for<'a> FnMut(<T as Trait<'a>>::Item),
 LL |     foo((), drop)
    |             ^^^^
    |             |
-   |             expected signature of `fn(<() as Trait<'a>>::Item) -> _`
+   |             expected signature of `for<'a> fn(<() as Trait<'a>>::Item) -> _`
    |             found signature of `fn(()) -> _`
 
 error[E0277]: the size for values of type `<() as Trait<'_>>::Item` cannot be known at compilation time