ui: improve suggestion test by addig the help message

Signed-off-by: Vincenzo Palazzo <[email protected]>

compiler/rustc_typeck/src/astconv/mod.rs

@@ -3015,7 +3015,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             let param_name = generics.params.next_type_param_name(None);
 
             let add_generic_sugg = if let Some(span) = generics.span_for_param_suggestion() {
-                let param_name = generics.params.next_type_param_name(Some(&impl_trait_name));
                 (span, format!(", {}: {}", param_name, impl_trait_name))
             } else {
                 (generics.span, format!("<{}: {}>", param_name, impl_trait_name))
@@ -3047,11 +3046,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     .map_or(false, |s| s.trim_end().ends_with('<'));
 
             let is_global = poly_trait_ref.trait_ref.path.is_global();
-            let is_local = if let Some(def_id) = poly_trait_ref.trait_ref.trait_def_id() {
-                def_id.is_local()
-            } else {
-                false
-            };
             let sugg = Vec::from_iter([
                 (
                     self_ty.span.shrink_to_lo(),
@@ -3077,9 +3071,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     rustc_errors::struct_span_err!(tcx.sess, self_ty.span, E0782, "{}", msg);
                 diag.multipart_suggestion_verbose(label, sugg, Applicability::MachineApplicable);
                 // check if the impl trait that we are considering is a impl of a local trait
-                if is_local {
-                    self.maybe_lint_blanket_trait_impl(&self_ty, &mut diag);
-                }
+                self.maybe_lint_blanket_trait_impl(&self_ty, &mut diag);
                 diag.emit();
             } else {
                 let msg = "trait objects without an explicit `dyn` are deprecated";
@@ -3094,10 +3086,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                             sugg,
                             Applicability::MachineApplicable,
                         );
-                        // check if the impl trait that we are considering is a impl of a local trait
-                        if is_local {
-                            self.maybe_lint_blanket_trait_impl::<()>(&self_ty, &mut diag);
-                        }
+                        self.maybe_lint_blanket_trait_impl::<()>(&self_ty, &mut diag);
                         diag.emit();
                     },
                 );

src/test/ui/suggestions/suggest-blanket-impl-local-trait.rs

@@ -12,33 +12,47 @@ trait GenericTrait<T> {}
 
 impl LocalTraitTwo for LocalTraitOne {}
 //~^ ERROR trait objects must include the `dyn` keyword
+//~| HELP add `dyn` keyword before this trait
+//~| HELP alternatively use a blanket implementation to implement `LocalTraitTwo` for all types that also implement `LocalTraitOne`
 
 impl fmt::Display for LocalTraitOne {
 //~^ ERROR trait objects must include the `dyn` keyword
+//~| HELP add `dyn` keyword before this trait
     fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result {
         todo!();
     }
 }
 
 impl fmt::Display for LocalTraitTwo + Send {
 //~^ ERROR trait objects must include the `dyn` keyword
+//~| HELP add `dyn` keyword before this trait
     fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result {
         todo!();
     }
 }
 
 impl LocalTraitOne for fmt::Display {}
 //~^ ERROR trait objects must include the `dyn` keyword
+//~| HELP add `dyn` keyword before this trait
+//~| HELP alternatively use a blanket implementation to implement `LocalTraitOne` for all types that also implement `fmt::Display`
+
 
 impl LocalTraitOne for fmt::Display + Send {}
 //~^ ERROR trait objects must include the `dyn` keyword
+//~| HELP add `dyn` keyword before this trait
+//~| HELP alternatively use a blanket implementation to implement `LocalTraitOne` for all types that also implement `fmt::Display + Send`
+
 
 impl<E> GenericTrait<E> for LocalTraitOne {}
 //~^ ERROR trait objects must include the `dyn` keyword
+//~| HELP add `dyn` keyword before this trait
+//~| HELP alternatively use a blanket implementation to implement `GenericTrait<E>` for all types that also implement `LocalTraitOne`
 
 trait GenericTraitTwo<T> {}
 
 impl<T, E> GenericTraitTwo<E> for GenericTrait<T> {}
 //~^ ERROR trait objects must include the `dyn` keyword
+//~| HELP add `dyn` keyword before this trait
+//~| HELP alternatively use a blanket implementation to implement `GenericTraitTwo<E>` for all types that also implement `GenericTrait<T>`
 
 fn main() {}

src/test/ui/suggestions/suggest-blanket-impl-local-trait.stderr

@@ -8,14 +8,14 @@ help: add `dyn` keyword before this trait
    |
 LL - impl LocalTraitTwo for LocalTraitOne {}
 LL + impl LocalTraitTwo for dyn LocalTraitOne {}
-   | 
+   |
 help: alternatively use a blanket implementation to implement `LocalTraitTwo` for all types that also implement `LocalTraitOne`
    |
 LL | impl<T: LocalTraitOne> LocalTraitTwo for T {}
    |     ++++++++++++++++++                   ~
 
 error[E0782]: trait objects must include the `dyn` keyword
-  --> $DIR/suggest-blanket-impl-local-trait.rs:16:23
+  --> $DIR/suggest-blanket-impl-local-trait.rs:18:23
    |
 LL | impl fmt::Display for LocalTraitOne {
    |                       ^^^^^^^^^^^^^
@@ -24,10 +24,10 @@ help: add `dyn` keyword before this trait
    |
 LL - impl fmt::Display for LocalTraitOne {
 LL + impl fmt::Display for dyn LocalTraitOne {
-   | 
+   |
 
 error[E0782]: trait objects must include the `dyn` keyword
-  --> $DIR/suggest-blanket-impl-local-trait.rs:23:23
+  --> $DIR/suggest-blanket-impl-local-trait.rs:26:23
    |
 LL | impl fmt::Display for LocalTraitTwo + Send {
    |                       ^^^^^^^^^^^^^^^^^^^^
@@ -36,10 +36,10 @@ help: add `dyn` keyword before this trait
    |
 LL - impl fmt::Display for LocalTraitTwo + Send {
 LL + impl fmt::Display for dyn LocalTraitTwo + Send {
-   | 
+   |
 
 error[E0782]: trait objects must include the `dyn` keyword
-  --> $DIR/suggest-blanket-impl-local-trait.rs:30:24
+  --> $DIR/suggest-blanket-impl-local-trait.rs:34:24
    |
 LL | impl LocalTraitOne for fmt::Display {}
    |                        ^^^^^^^^^^^^
@@ -48,10 +48,14 @@ help: add `dyn` keyword before this trait
    |
 LL - impl LocalTraitOne for fmt::Display {}
 LL + impl LocalTraitOne for dyn fmt::Display {}
-   | 
+   |
+help: alternatively use a blanket implementation to implement `LocalTraitOne` for all types that also implement `fmt::Display`
+   |
+LL | impl<T: fmt::Display> LocalTraitOne for T {}
+   |     +++++++++++++++++                   ~
 
 error[E0782]: trait objects must include the `dyn` keyword
-  --> $DIR/suggest-blanket-impl-local-trait.rs:33:24
+  --> $DIR/suggest-blanket-impl-local-trait.rs:40:24
    |
 LL | impl LocalTraitOne for fmt::Display + Send {}
    |                        ^^^^^^^^^^^^^^^^^^^
@@ -60,10 +64,14 @@ help: add `dyn` keyword before this trait
    |
 LL - impl LocalTraitOne for fmt::Display + Send {}
 LL + impl LocalTraitOne for dyn fmt::Display + Send {}
-   | 
+   |
+help: alternatively use a blanket implementation to implement `LocalTraitOne` for all types that also implement `fmt::Display + Send`
+   |
+LL | impl<T: fmt::Display + Send> LocalTraitOne for T {}
+   |     ++++++++++++++++++++++++                   ~
 
 error[E0782]: trait objects must include the `dyn` keyword
-  --> $DIR/suggest-blanket-impl-local-trait.rs:36:29
+  --> $DIR/suggest-blanket-impl-local-trait.rs:46:29
    |
 LL | impl<E> GenericTrait<E> for LocalTraitOne {}
    |                             ^^^^^^^^^^^^^
@@ -72,14 +80,14 @@ help: add `dyn` keyword before this trait
    |
 LL - impl<E> GenericTrait<E> for LocalTraitOne {}
 LL + impl<E> GenericTrait<E> for dyn LocalTraitOne {}
-   | 
+   |
 help: alternatively use a blanket implementation to implement `GenericTrait<E>` for all types that also implement `LocalTraitOne`
    |
-LL | impl<E, L: LocalTraitOne> GenericTrait<E> for T {}
+LL | impl<E, T: LocalTraitOne> GenericTrait<E> for T {}
    |       ++++++++++++++++++                      ~
 
 error[E0782]: trait objects must include the `dyn` keyword
-  --> $DIR/suggest-blanket-impl-local-trait.rs:41:35
+  --> $DIR/suggest-blanket-impl-local-trait.rs:53:35
    |
 LL | impl<T, E> GenericTraitTwo<E> for GenericTrait<T> {}
    |                                   ^^^^^^^^^^^^^^^
@@ -88,10 +96,10 @@ help: add `dyn` keyword before this trait
    |
 LL - impl<T, E> GenericTraitTwo<E> for GenericTrait<T> {}
 LL + impl<T, E> GenericTraitTwo<E> for dyn GenericTrait<T> {}
-   | 
+   |
 help: alternatively use a blanket implementation to implement `GenericTraitTwo<E>` for all types that also implement `GenericTrait<T>`
    |
-LL | impl<T, E, G: GenericTrait<T>> GenericTraitTwo<E> for U {}
+LL | impl<T, E, U: GenericTrait<T>> GenericTraitTwo<E> for U {}
    |          ++++++++++++++++++++                         ~
 
 error: aborting due to 7 previous errors