Name higher-ranked lifetimes properly while displaying

Now they don't shadow other lifetimes.

src/test/ui/anonymous-higher-ranked-lifetime.rs

@@ -0,0 +1,40 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+fn main() {
+    f1(|_: (), _: ()| {});
+    f2(|_: (), _: ()| {});
+    f3(|_: (), _: ()| {});
+    f4(|_: (), _: ()| {});
+    f5(|_: (), _: ()| {});
+    g1(|_: (), _: ()| {});
+    g2(|_: (), _: ()| {});
+    g3(|_: (), _: ()| {});
+    g4(|_: (), _: ()| {});
+    h1(|_: (), _: (), _: (), _: ()| {});
+    h2(|_: (), _: (), _: (), _: ()| {});
+}
+
+// Basic
+fn f1<F>(_: F) where F: Fn(&(), &()) {}
+fn f2<F>(_: F) where F: for<'a> Fn(&'a (), &()) {}
+fn f3<'a, F>(_: F) where F: Fn(&'a (), &()) {}
+fn f4<F>(_: F) where F: for<'r> Fn(&(), &'r ()) {}
+fn f5<F>(_: F) where F: for<'r> Fn(&'r (), &'r ()) {}
+
+// Nested
+fn g1<F>(_: F) where F: Fn(&(), Box<Fn(&())>) {}
+fn g2<F>(_: F) where F: Fn(&(), fn(&())) {}
+fn g3<F>(_: F) where F: for<'s> Fn(&'s (), Box<Fn(&())>) {}
+fn g4<F>(_: F) where F: Fn(&(), for<'r> fn(&'r ())) {}
+
+// Mixed
+fn h1<F>(_: F) where F: Fn(&(), Box<Fn(&())>, &(), fn(&(), &())) {}
+fn h2<F>(_: F) where F: for<'t0> Fn(&(), Box<Fn(&())>, &'t0 (), fn(&(), &())) {}

src/test/ui/anonymous-higher-ranked-lifetime.stderr

@@ -0,0 +1,112 @@
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:12:5
+   |
+12 |     f1(|_: (), _: ()| {});
+   |     ^^ ----------------- found signature of `fn((), ()) -> _`
+   |     |
+   |     expected signature of `for<'r, 's> fn(&'r (), &'s ()) -> _`
+   |
+   = note: required by `f1`
+
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:13:5
+   |
+13 |     f2(|_: (), _: ()| {});
+   |     ^^ ----------------- found signature of `fn((), ()) -> _`
+   |     |
+   |     expected signature of `for<'a, 'r> fn(&'a (), &'r ()) -> _`
+   |
+   = note: required by `f2`
+
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:14:5
+   |
+14 |     f3(|_: (), _: ()| {});
+   |     ^^ ----------------- found signature of `fn((), ()) -> _`
+   |     |
+   |     expected signature of `for<'r> fn(&(), &'r ()) -> _`
+   |
+   = note: required by `f3`
+
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:15:5
+   |
+15 |     f4(|_: (), _: ()| {});
+   |     ^^ ----------------- found signature of `fn((), ()) -> _`
+   |     |
+   |     expected signature of `for<'s, 'r> fn(&'s (), &'r ()) -> _`
+   |
+   = note: required by `f4`
+
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:16:5
+   |
+16 |     f5(|_: (), _: ()| {});
+   |     ^^ ----------------- found signature of `fn((), ()) -> _`
+   |     |
+   |     expected signature of `for<'r> fn(&'r (), &'r ()) -> _`
+   |
+   = note: required by `f5`
+
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:17:5
+   |
+17 |     g1(|_: (), _: ()| {});
+   |     ^^ ----------------- found signature of `fn((), ()) -> _`
+   |     |
+   |     expected signature of `for<'r> fn(&'r (), std::boxed::Box<for<'s> std::ops::Fn(&'s ()) + 'static>) -> _`
+   |
+   = note: required by `g1`
+
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:18:5
+   |
+18 |     g2(|_: (), _: ()| {});
+   |     ^^ ----------------- found signature of `fn((), ()) -> _`
+   |     |
+   |     expected signature of `for<'r> fn(&'r (), for<'s> fn(&'s ())) -> _`
+   |
+   = note: required by `g2`
+
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:19:5
+   |
+19 |     g3(|_: (), _: ()| {});
+   |     ^^ ----------------- found signature of `fn((), ()) -> _`
+   |     |
+   |     expected signature of `for<'s> fn(&'s (), std::boxed::Box<for<'r> std::ops::Fn(&'r ()) + 'static>) -> _`
+   |
+   = note: required by `g3`
+
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:20:5
+   |
+20 |     g4(|_: (), _: ()| {});
+   |     ^^ ----------------- found signature of `fn((), ()) -> _`
+   |     |
+   |     expected signature of `for<'s> fn(&'s (), for<'r> fn(&'r ())) -> _`
+   |
+   = note: required by `g4`
+
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:21:5
+   |
+21 |     h1(|_: (), _: (), _: (), _: ()| {});
+   |     ^^ ------------------------------- found signature of `fn((), (), (), ()) -> _`
+   |     |
+   |     expected signature of `for<'r, 's> fn(&'r (), std::boxed::Box<for<'t0> std::ops::Fn(&'t0 ()) + 'static>, &'s (), for<'t0, 't1> fn(&'t0 (), &'t1 ())) -> _`
+   |
+   = note: required by `h1`
+
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:22:5
+   |
+22 |     h2(|_: (), _: (), _: (), _: ()| {});
+   |     ^^ ------------------------------- found signature of `fn((), (), (), ()) -> _`
+   |     |
+   |     expected signature of `for<'r, 't0> fn(&'r (), std::boxed::Box<for<'s> std::ops::Fn(&'s ()) + 'static>, &'t0 (), for<'s, 't1> fn(&'s (), &'t1 ())) -> _`
+   |
+   = note: required by `h2`
+
+error: aborting due to 11 previous errors
+

src/test/ui/regions-fn-subtyping-return-static.stderr

@@ -4,7 +4,7 @@ error[E0308]: mismatched types
 51 |     want_F(bar); //~ ERROR E0308
    |            ^^^ expected concrete lifetime, found bound lifetime parameter 'cx
    |
-   = note: expected type `fn(&'cx S) -> &'cx S`
+   = note: expected type `for<'cx> fn(&'cx S) -> &'cx S`
               found type `fn(&'a S) -> &S {bar::<'_>}`
 
 error: aborting due to previous error