review comment: wording

Author: estebank

src/librustc/infer/error_reporting/mod.rs

@@ -1340,16 +1340,18 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                             err.span_label(
                                 *sp,
                                 format!(
-                                    "{}the {} {}{}{}",
-                                    if count > 1 { "one of " } else { "" },
-                                    target,
-                                    key,
-                                    pluralize!(count),
+                                    "{}{}{} {}{}",
                                     if sp.is_desugaring(DesugaringKind::Async) {
-                                        " in the `Output` of this `async fn`"
+                                        "the `Output` of this `async fn`'s "
+                                    } else if count == 1 {
+                                        "the "
                                     } else {
                                         ""
                                     },
+                                    if count > 1 { "one of the " } else { "" },
+                                    target,
+                                    key,
+                                    pluralize!(count),
                                 ),
                             );
                         }

src/test/ui/async-await/dont-suggest-missing-await.stderr

@@ -2,7 +2,7 @@ error[E0308]: mismatched types
   --> $DIR/dont-suggest-missing-await.rs:14:18
    |
 LL | async fn make_u32() -> u32 {
-   |                        --- the found opaque type in the `Output` of this `async fn`
+   |                        --- the `Output` of this `async fn`'s found opaque type
 ...
 LL |         take_u32(x)
    |                  ^ expected `u32`, found opaque type

src/test/ui/async-await/suggest-missing-await-closure.stderr

@@ -2,7 +2,7 @@ error[E0308]: mismatched types
   --> $DIR/suggest-missing-await-closure.rs:16:18
    |
 LL | async fn make_u32() -> u32 {
-   |                        --- the found opaque type in the `Output` of this `async fn`
+   |                        --- the `Output` of this `async fn`'s found opaque type
 ...
 LL |         take_u32(x)
    |                  ^

src/test/ui/async-await/suggest-missing-await.stderr

@@ -2,7 +2,7 @@ error[E0308]: mismatched types
   --> $DIR/suggest-missing-await.rs:13:14
    |
 LL | async fn make_u32() -> u32 {
-   |                        --- the found opaque type in the `Output` of this `async fn`
+   |                        --- the `Output` of this `async fn`'s found opaque type
 ...
 LL |     take_u32(x)
    |              ^
@@ -17,7 +17,7 @@ error[E0308]: mismatched types
   --> $DIR/suggest-missing-await.rs:23:5
    |
 LL | async fn dummy() {}
-   |                  - the found opaque type in the `Output` of this `async fn`
+   |                  - the `Output` of this `async fn`'s found opaque type
 ...
 LL |     dummy()
    |     ^^^^^^^ expected `()`, found opaque type