Improve E0178 suggestion placement

src/test/ui/did_you_mean/E0178.rs

@@ -0,0 +1,21 @@
+// Copyright 2016 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.
+
+trait Foo {}
+
+struct Bar<'a> {
+    w: &'a Foo + Copy,
+    x: &'a Foo + 'a,
+    y: &'a mut Foo + 'a,
+    z: fn() -> Foo + 'a,
+}
+
+fn main() {
+}

src/test/ui/did_you_mean/E0178.stderr

@@ -0,0 +1,26 @@
+error[E0178]: expected a path on the left-hand side of `+`, not `&'a Foo`
+  --> $DIR/E0178.rs:14:8
+   |
+14 |     w: &'a Foo + Copy,
+   |        ^^^^^^^^^^^^^^ try adding parentheses: `&'a (Foo + Copy)`
+
+error[E0178]: expected a path on the left-hand side of `+`, not `&'a Foo`
+  --> $DIR/E0178.rs:15:8
+   |
+15 |     x: &'a Foo + 'a,
+   |        ^^^^^^^^^^^^ try adding parentheses: `&'a (Foo + 'a)`
+
+error[E0178]: expected a path on the left-hand side of `+`, not `&'a mut Foo`
+  --> $DIR/E0178.rs:16:8
+   |
+16 |     y: &'a mut Foo + 'a,
+   |        ^^^^^^^^^^^^^^^^ try adding parentheses: `&'a mut (Foo + 'a)`
+
+error[E0178]: expected a path on the left-hand side of `+`, not `fn() -> Foo`
+  --> $DIR/E0178.rs:17:8
+   |
+17 |     z: fn() -> Foo + 'a,
+   |        ^^^^^^^^^^^^^^^^ perhaps you forgot parentheses?
+
+error: aborting due to 4 previous errors
+

src/test/ui/did_you_mean/trait-object-reference-without-parens-suggestion.rs

@@ -0,0 +1,14 @@
+// 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() {
+    let _: &Copy + 'static;
+    let _: &'static Copy + 'static;
+}

src/test/ui/did_you_mean/trait-object-reference-without-parens-suggestion.stderr

@@ -0,0 +1,22 @@
+error[E0178]: expected a path on the left-hand side of `+`, not `&Copy`
+  --> $DIR/trait-object-reference-without-parens-suggestion.rs:12:12
+   |
+12 |     let _: &Copy + 'static;
+   |            ^^^^^^^^^^^^^^^ try adding parentheses: `&(Copy + 'static)`
+
+error[E0178]: expected a path on the left-hand side of `+`, not `&'static Copy`
+  --> $DIR/trait-object-reference-without-parens-suggestion.rs:13:12
+   |
+13 |     let _: &'static Copy + 'static;
+   |            ^^^^^^^^^^^^^^^^^^^^^^^ try adding parentheses: `&'static (Copy + 'static)`
+
+error[E0038]: the trait `std::marker::Copy` cannot be made into an object
+  --> $DIR/trait-object-reference-without-parens-suggestion.rs:12:12
+   |
+12 |     let _: &Copy + 'static;
+   |            ^^^^^ the trait `std::marker::Copy` cannot be made into an object
+   |
+   = note: the trait cannot require that `Self : Sized`
+
+error: aborting due to previous error
+