Add article after "to"

Also added missing backtick in "you can cast" message.

Author: camelid

compiler/rustc_typeck/src/check/demand.rs

@@ -753,16 +753,18 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
 
         let msg = format!(
-            "you can convert {} `{}` to `{}`",
+            "you can convert {} `{}` to {} `{}`",
             checked_ty.kind().article(),
             checked_ty,
-            expected_ty
+            expected_ty.kind().article(),
+            expected_ty,
         );
         let cast_msg = format!(
-            "you can cast {} `{} to `{}`",
+            "you can cast {} `{}` to {} `{}`",
             checked_ty.kind().article(),
             checked_ty,
-            expected_ty
+            expected_ty.kind().article(),
+            expected_ty,
         );
         let lit_msg = format!(
             "change the type of the numeric literal from `{}` to `{}`",

src/test/ui/associated-types/associated-types-path-2.stderr

@@ -47,7 +47,7 @@ LL |     let _: i32 = f2(2i32);
    |            |
    |            expected due to this
    |
-help: you can convert a `u32` to `i32` and panic if the converted value wouldn't fit
+help: you can convert a `u32` to an `i32` and panic if the converted value wouldn't fit
    |
 LL |     let _: i32 = f2(2i32).try_into().unwrap();
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

src/test/ui/indexing-requires-a-uint.stderr

@@ -13,7 +13,7 @@ error[E0308]: mismatched types
 LL |     bar::<isize>(i);  // i should not be re-coerced back to an isize
    |                  ^ expected `isize`, found `usize`
    |
-help: you can convert a `usize` to `isize` and panic if the converted value wouldn't fit
+help: you can convert a `usize` to an `isize` and panic if the converted value wouldn't fit
    |
 LL |     bar::<isize>(i.try_into().unwrap());  // i should not be re-coerced back to an isize
    |                  ^^^^^^^^^^^^^^^^^^^^^