change from review and show full type if it can be deref

compiler/rustc_typeck/src/check/method/suggest.rs

@@ -388,27 +388,30 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         let mut ty_str_reported = ty_str.clone();
                         if let ty::Adt(_, ref generics) = actual.kind() {
                             if generics.len() > 0 {
-                                let candidate_numbers: usize = self
-                                    .autoderef(span, actual)
-                                    .map(|(ty, _)| {
-                                        if let ty::Adt(ref adt_deref, _) = ty.kind() {
-                                            self.tcx
-                                                .inherent_impls(adt_deref.did)
-                                                .iter()
-                                                .filter_map(|def_id| {
-                                                    self.associated_item(
-                                                        *def_id,
-                                                        item_name,
-                                                        Namespace::ValueNS,
-                                                    )
-                                                })
-                                                .count()
-                                        } else {
-                                            0
-                                        }
-                                    })
-                                    .sum();
-                                if candidate_numbers == 0 && unsatisfied_predicates.is_empty() {
+                                let mut autoderef = self.autoderef(span, actual);
+                                let candidate_found = autoderef.any(|(ty, _)| {
+                                    if let ty::Adt(ref adt_deref, _) = ty.kind() {
+                                        self.tcx
+                                            .inherent_impls(adt_deref.did)
+                                            .iter()
+                                            .filter_map(|def_id| {
+                                                self.associated_item(
+                                                    *def_id,
+                                                    item_name,
+                                                    Namespace::ValueNS,
+                                                )
+                                            })
+                                            .count()
+                                            >= 1
+                                    } else {
+                                        false
+                                    }
+                                });
+                                let has_deref = autoderef.step_count() > 0;
+                                if !candidate_found
+                                    && !has_deref
+                                    && unsatisfied_predicates.is_empty()
+                                {
                                     if let Some((path_string, _)) = ty_str.split_once('<') {
                                         ty_str_reported = path_string.to_string();
                                     }
@@ -501,8 +504,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                                 // So we avoid suggestion method with Box<Self>
                                                 // for instance
                                                 self.tcx.at(span).type_of(*def_id) != actual
-                                                    && self.tcx.at(span).type_of(*def_id)
-                                                        != rcvr_ty
+                                                    && self.tcx.at(span).type_of(*def_id) != rcvr_ty
                                             }
                                             (Mode::Path, false, _) => true,
                                             _ => false,
@@ -515,38 +517,21 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             if inherent_impls_candidate.len() > 0 {
                                 inherent_impls_candidate.sort();
                                 inherent_impls_candidate.dedup();
+                                let type_candidates = inherent_impls_candidate
+                                    .iter()
+                                    .map(|impl_item| self.tcx.at(span).type_of(*impl_item))
+                                    .collect::<Vec<_>>();
                                 // number of type to shows at most.
-                                const LIMIT: usize = 3;
-                                let mut note = format!("the {item_kind} was found for");
-                                if inherent_impls_candidate.len() > 1 {
-                                    for impl_item in inherent_impls_candidate.iter().take(LIMIT - 2)
-                                    {
-                                        let impl_ty = self.tcx.at(span).type_of(*impl_item);
-                                        note = format!("{} {},", note, impl_ty);
-                                    }
-                                    let impl_ty = self.tcx.at(span).type_of(
-                                        inherent_impls_candidate
-                                            [inherent_impls_candidate.len() - 1],
-                                    );
-                                    if inherent_impls_candidate.len() > LIMIT {
-                                        note = format!("{} {},", note, impl_ty);
-                                    } else {
-                                        note = format!("{} {} and", note, impl_ty);
-                                    }
+                                let limit = if type_candidates.len() == 4 { 4 } else { 3 };
+                                for ty in type_candidates.iter().take(limit) {
+                                    err.note(&format!("the {item_kind} was found for {}", ty));
                                 }
-                                let impl_ty = self
-                                    .tcx
-                                    .at(span)
-                                    .type_of(*inherent_impls_candidate.last().unwrap());
-                                note = format!("{} {}", note, impl_ty);
-                                if inherent_impls_candidate.len() > LIMIT {
-                                    note = format!(
-                                        "{} and {} more",
-                                        note,
-                                        inherent_impls_candidate.len() - LIMIT
-                                    );
+                                if type_candidates.len() > limit {
+                                    err.note(&format!(
+                                        "the {item_kind} was found for {} more types",
+                                        type_candidates.len() - limit
+                                    ));
                                 }
-                                err.note(&format!("{}.", note));
                             }
                         }
                     } else {

src/test/ui/auto-ref-slice-plus-ref.stderr

@@ -1,4 +1,4 @@
-error[E0599]: no method named `test_mut` found for struct `Vec` in the current scope
+error[E0599]: no method named `test_mut` found for struct `Vec<{integer}>` in the current scope
   --> $DIR/auto-ref-slice-plus-ref.rs:7:7
    |
 LL |     a.test_mut();
@@ -11,7 +11,7 @@ note: `MyIter` defines an item `test_mut`, perhaps you need to implement it
 LL | trait MyIter {
    | ^^^^^^^^^^^^
 
-error[E0599]: no method named `test` found for struct `Vec` in the current scope
+error[E0599]: no method named `test` found for struct `Vec<{integer}>` in the current scope
   --> $DIR/auto-ref-slice-plus-ref.rs:8:7
    |
 LL |     a.test();

src/test/ui/class-cast-to-trait.stderr

@@ -1,4 +1,4 @@
-error[E0599]: no method named `eat` found for struct `Box` in the current scope
+error[E0599]: no method named `eat` found for struct `Box<dyn Noisy>` in the current scope
   --> $DIR/class-cast-to-trait.rs:53:8
    |
 LL |   nyan.eat();

src/test/ui/impl-trait/no-method-suggested-traits.stderr

@@ -16,7 +16,7 @@ LL | use no_method_suggested_traits::qux::PrivPub;
 LL | use no_method_suggested_traits::Reexported;
    |
 
-error[E0599]: no method named `method` found for struct `Rc` in the current scope
+error[E0599]: no method named `method` found for struct `Rc<&mut Box<&u32>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:26:44
    |
 LL |     std::rc::Rc::new(&mut Box::new(&1u32)).method();
@@ -46,7 +46,7 @@ help: the following trait is implemented but not in scope; perhaps add a `use` f
 LL | use foo::Bar;
    |
 
-error[E0599]: no method named `method` found for struct `Rc` in the current scope
+error[E0599]: no method named `method` found for struct `Rc<&mut Box<&char>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:32:43
    |
 LL |     std::rc::Rc::new(&mut Box::new(&'a')).method();
@@ -70,7 +70,7 @@ help: the following trait is implemented but not in scope; perhaps add a `use` f
 LL | use no_method_suggested_traits::foo::PubPub;
    |
 
-error[E0599]: no method named `method` found for struct `Rc` in the current scope
+error[E0599]: no method named `method` found for struct `Rc<&mut Box<&i32>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:37:44
    |
 LL |     std::rc::Rc::new(&mut Box::new(&1i32)).method();
@@ -98,7 +98,7 @@ LL |     Foo.method();
            candidate #3: `no_method_suggested_traits::qux::PrivPub`
            candidate #4: `Reexported`
 
-error[E0599]: no method named `method` found for struct `Rc` in the current scope
+error[E0599]: no method named `method` found for struct `Rc<&mut Box<&Foo>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:42:43
    |
 LL |     std::rc::Rc::new(&mut Box::new(&Foo)).method();
@@ -124,7 +124,7 @@ note: `foo::Bar` defines an item `method2`, perhaps you need to implement it
 LL |     pub trait Bar {
    |     ^^^^^^^^^^^^^
 
-error[E0599]: no method named `method2` found for struct `Rc` in the current scope
+error[E0599]: no method named `method2` found for struct `Rc<&mut Box<&u64>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:47:44
    |
 LL |     std::rc::Rc::new(&mut Box::new(&1u64)).method2();
@@ -150,7 +150,7 @@ note: `foo::Bar` defines an item `method2`, perhaps you need to implement it
 LL |     pub trait Bar {
    |     ^^^^^^^^^^^^^
 
-error[E0599]: no method named `method2` found for struct `Rc` in the current scope
+error[E0599]: no method named `method2` found for struct `Rc<&mut Box<&no_method_suggested_traits::Foo>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:52:71
    |
 LL |     std::rc::Rc::new(&mut Box::new(&no_method_suggested_traits::Foo)).method2();
@@ -176,7 +176,7 @@ note: `foo::Bar` defines an item `method2`, perhaps you need to implement it
 LL |     pub trait Bar {
    |     ^^^^^^^^^^^^^
 
-error[E0599]: no method named `method2` found for struct `Rc` in the current scope
+error[E0599]: no method named `method2` found for struct `Rc<&mut Box<&no_method_suggested_traits::Bar>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:56:74
    |
 LL |     std::rc::Rc::new(&mut Box::new(&no_method_suggested_traits::Bar::X)).method2();
@@ -202,7 +202,7 @@ LL |     Foo.method3();
    = note: the following trait defines an item `method3`, perhaps you need to implement it:
            candidate #1: `PubPub`
 
-error[E0599]: no method named `method3` found for struct `Rc` in the current scope
+error[E0599]: no method named `method3` found for struct `Rc<&mut Box<&Foo>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:61:43
    |
 LL |     std::rc::Rc::new(&mut Box::new(&Foo)).method3();
@@ -225,7 +225,7 @@ LL |     Bar::X.method3();
    = note: the following trait defines an item `method3`, perhaps you need to implement it:
            candidate #1: `PubPub`
 
-error[E0599]: no method named `method3` found for struct `Rc` in the current scope
+error[E0599]: no method named `method3` found for struct `Rc<&mut Box<&Bar>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:65:46
    |
 LL |     std::rc::Rc::new(&mut Box::new(&Bar::X)).method3();
@@ -241,7 +241,7 @@ error[E0599]: no method named `method3` found for type `usize` in the current sc
 LL |     1_usize.method3();
    |             ^^^^^^^ method not found in `usize`
 
-error[E0599]: no method named `method3` found for struct `Rc` in the current scope
+error[E0599]: no method named `method3` found for struct `Rc<&mut Box<&usize>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:70:47
    |
 LL |     std::rc::Rc::new(&mut Box::new(&1_usize)).method3();
@@ -253,7 +253,7 @@ error[E0599]: no method named `method3` found for struct `no_method_suggested_tr
 LL |     no_method_suggested_traits::Foo.method3();
    |                                     ^^^^^^^ method not found in `no_method_suggested_traits::Foo`
 
-error[E0599]: no method named `method3` found for struct `Rc` in the current scope
+error[E0599]: no method named `method3` found for struct `Rc<&mut Box<&no_method_suggested_traits::Foo>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:72:71
    |
 LL |     std::rc::Rc::new(&mut Box::new(&no_method_suggested_traits::Foo)).method3();
@@ -265,7 +265,7 @@ error[E0599]: no method named `method3` found for enum `no_method_suggested_trai
 LL |     no_method_suggested_traits::Bar::X.method3();
    |                                        ^^^^^^^ method not found in `no_method_suggested_traits::Bar`
 
-error[E0599]: no method named `method3` found for struct `Rc` in the current scope
+error[E0599]: no method named `method3` found for struct `Rc<&mut Box<&no_method_suggested_traits::Bar>>` in the current scope
   --> $DIR/no-method-suggested-traits.rs:75:74
    |
 LL |     std::rc::Rc::new(&mut Box::new(&no_method_suggested_traits::Bar::X)).method3();

src/test/ui/issues/issue-30123.stderr

@@ -4,7 +4,7 @@ error[E0599]: no function or associated item named `new_undirected` found for st
 LL |     let ug = Graph::<i32, i32>::new_undirected();
    |                                 ^^^^^^^^^^^^^^ function or associated item not found in `issue_30123_aux::Graph<i32, i32>`
    |
-   = note: The function or associated item was found for issue_30123_aux::Graph<N, E, Undirected>.
+   = note: the function or associated item was found for issue_30123_aux::Graph<N, E, Undirected>
 
 error: aborting due to previous error
 

src/test/ui/methods/method-not-found-generic-arg-elision.rs

@@ -1,6 +1,7 @@
 // Test for issue 81576
 // Remove generic arguments if no method is found for all possible generic argument
 
+use std::marker::PhantomData;
 
 struct Wrapper2<'a, T, const C: usize> {
     x: &'a T,
@@ -19,8 +20,6 @@ impl<'a, const C: usize> Wrapper2<'a, i32, C> {
 }
 struct Wrapper<T>(T);
 
-
-
 impl Wrapper<i8> {
     fn method(&self) {}
 }
@@ -62,6 +61,20 @@ impl Other {
     fn other(&self) {}
 }
 
+struct Struct<T>{
+    _phatom: PhantomData<T>
+}
+
+impl<T> Default for Struct<T> {
+    fn default() -> Self {
+        Self{ _phatom: PhantomData }
+    }
+}
+
+impl<T: Clone + Copy + PartialEq + Eq + PartialOrd + Ord> Struct<T> {
+    fn method(&self) {}
+}
+
 fn main() {
     let point_f64 = Point{ x: 1_f64, y: 1_f64};
     let d = point_f64.distance();
@@ -87,4 +100,7 @@ fn main() {
     let a = vec![1, 2, 3];
     a.not_found();
     //~^ ERROR no method named `not_found` found for struct `Vec
+    let s = Struct::<f64>::default();
+    s.method();
+    //~^ ERROR the method `method` exists for struct `Struct<f64>`, but its trait bounds were not satisfied
 }