Make parse error suggestions verbose and fix spans

Go over all structured parser suggestions and make them verbose style.

When suggesting to add or remove delimiters, turn them into multiple suggestion parts.

3 files changed, 84 insertions, 14 deletions

diff --git a/tests/ui/impl-trait/extra-impl-in-trait-impl.stderr b/tests/ui/impl-trait/extra-impl-in-trait-impl.stderr
index 91c7da5a04f..e4d14c4807c 100644
--- a/tests/ui/impl-trait/extra-impl-in-trait-impl.stderr
+++ b/tests/ui/impl-trait/extra-impl-in-trait-impl.stderr
@@ -2,25 +2,35 @@ error: unexpected `impl` keyword
   --> $DIR/extra-impl-in-trait-impl.rs:8:18
    |
 LL | impl<T: Default> impl Default for S<T> {
-   |                  ^^^^^ help: remove the extra `impl`
+   |                  ^^^^^
    |
 note: this is parsed as an `impl Trait` type, but a trait is expected at this position
   --> $DIR/extra-impl-in-trait-impl.rs:8:18
    |
 LL | impl<T: Default> impl Default for S<T> {
    |                  ^^^^^^^^^^^^
+help: remove the extra `impl`
+   |
+LL - impl<T: Default> impl Default for S<T> {
+LL + impl<T: Default> Default for S<T> {
+   |
 
 error: unexpected `impl` keyword
   --> $DIR/extra-impl-in-trait-impl.rs:14:6
    |
 LL | impl impl Default for S2 {
-   |      ^^^^^ help: remove the extra `impl`
+   |      ^^^^^
    |
 note: this is parsed as an `impl Trait` type, but a trait is expected at this position
   --> $DIR/extra-impl-in-trait-impl.rs:14:6
    |
 LL | impl impl Default for S2 {
    |      ^^^^^^^^^^^^
+help: remove the extra `impl`
+   |
+LL - impl impl Default for S2 {
+LL + impl Default for S2 {
+   |
 
 error: aborting due to 2 previous errors
 
diff --git a/tests/ui/impl-trait/impl-fn-parsing-ambiguities.stderr b/tests/ui/impl-trait/impl-fn-parsing-ambiguities.stderr
index e0955faac7c..94b6ffdd912 100644
--- a/tests/ui/impl-trait/impl-fn-parsing-ambiguities.stderr
+++ b/tests/ui/impl-trait/impl-fn-parsing-ambiguities.stderr
@@ -2,13 +2,23 @@ error: ambiguous `+` in a type
   --> $DIR/impl-fn-parsing-ambiguities.rs:4:27
    |
 LL | fn a() -> impl Fn(&u8) -> impl Debug + '_ {
-   |                           ^^^^^^^^^^^^^^^ help: use parentheses to disambiguate: `(impl Debug + '_)`
+   |                           ^^^^^^^^^^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | fn a() -> impl Fn(&u8) -> (impl Debug + '_) {
+   |                           +               +
 
 error: ambiguous `+` in a type
   --> $DIR/impl-fn-parsing-ambiguities.rs:10:24
    |
 LL | fn b() -> impl Fn() -> impl Debug + Send {
-   |                        ^^^^^^^^^^^^^^^^^ help: use parentheses to disambiguate: `(impl Debug + Send)`
+   |                        ^^^^^^^^^^^^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | fn b() -> impl Fn() -> (impl Debug + Send) {
+   |                        +                 +
 
 error[E0657]: `impl Trait` cannot capture higher-ranked lifetime from outer `impl Trait`
   --> $DIR/impl-fn-parsing-ambiguities.rs:4:40
diff --git a/tests/ui/impl-trait/impl-trait-plus-priority.stderr b/tests/ui/impl-trait/impl-trait-plus-priority.stderr
index 205d9b0b75e..03e7910095a 100644
--- a/tests/ui/impl-trait/impl-trait-plus-priority.stderr
+++ b/tests/ui/impl-trait/impl-trait-plus-priority.stderr
@@ -2,19 +2,34 @@ error: ambiguous `+` in a type
   --> $DIR/impl-trait-plus-priority.rs:23:18
    |
 LL | type A = fn() -> impl A +;
-   |                  ^^^^^^^^ help: use parentheses to disambiguate: `(impl A)`
+   |                  ^^^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | type A = fn() -> (impl A +);
+   |                  +        +
 
 error: ambiguous `+` in a type
   --> $DIR/impl-trait-plus-priority.rs:25:18
    |
 LL | type A = fn() -> impl A + B;
-   |                  ^^^^^^^^^^ help: use parentheses to disambiguate: `(impl A + B)`
+   |                  ^^^^^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | type A = fn() -> (impl A + B);
+   |                  +          +
 
 error: ambiguous `+` in a type
   --> $DIR/impl-trait-plus-priority.rs:27:18
    |
 LL | type A = fn() -> dyn A + B;
-   |                  ^^^^^^^^^ help: use parentheses to disambiguate: `(dyn A + B)`
+   |                  ^^^^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | type A = fn() -> (dyn A + B);
+   |                  +         +
 
 error[E0178]: expected a path on the left-hand side of `+`, not `fn() -> A`
   --> $DIR/impl-trait-plus-priority.rs:29:10
@@ -26,43 +41,78 @@ error: ambiguous `+` in a type
   --> $DIR/impl-trait-plus-priority.rs:32:18
    |
 LL | type A = Fn() -> impl A +;
-   |                  ^^^^^^^^ help: use parentheses to disambiguate: `(impl A)`
+   |                  ^^^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | type A = Fn() -> (impl A +);
+   |                  +        +
 
 error: ambiguous `+` in a type
   --> $DIR/impl-trait-plus-priority.rs:34:18
    |
 LL | type A = Fn() -> impl A + B;
-   |                  ^^^^^^^^^^ help: use parentheses to disambiguate: `(impl A + B)`
+   |                  ^^^^^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | type A = Fn() -> (impl A + B);
+   |                  +          +
 
 error: ambiguous `+` in a type
   --> $DIR/impl-trait-plus-priority.rs:36:18
    |
 LL | type A = Fn() -> dyn A + B;
-   |                  ^^^^^^^^^ help: use parentheses to disambiguate: `(dyn A + B)`
+   |                  ^^^^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | type A = Fn() -> (dyn A + B);
+   |                  +         +
 
 error: ambiguous `+` in a type
   --> $DIR/impl-trait-plus-priority.rs:40:11
    |
 LL | type A = &impl A +;
-   |           ^^^^^^^^ help: use parentheses to disambiguate: `(impl A)`
+   |           ^^^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | type A = &(impl A +);
+   |           +        +
 
 error: ambiguous `+` in a type
   --> $DIR/impl-trait-plus-priority.rs:42:11
    |
 LL | type A = &impl A + B;
-   |           ^^^^^^^^^^ help: use parentheses to disambiguate: `(impl A + B)`
+   |           ^^^^^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | type A = &(impl A + B);
+   |           +          +
 
 error: ambiguous `+` in a type
   --> $DIR/impl-trait-plus-priority.rs:44:11
    |
 LL | type A = &dyn A + B;
-   |           ^^^^^^^^^ help: use parentheses to disambiguate: `(dyn A + B)`
+   |           ^^^^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | type A = &(dyn A + B);
+   |           +         +
 
 error[E0178]: expected a path on the left-hand side of `+`, not `&A`
   --> $DIR/impl-trait-plus-priority.rs:46:10
    |
 LL | type A = &A + B;
-   |          ^^^^^^ help: try adding parentheses: `&(A + B)`
+   |          ^^^^^^
+   |
+help: try adding parentheses
+   |
+LL | type A = &(A + B);
+   |           +     +
 
 error: aborting due to 11 previous errors