Auto merge of rust-lang#15864 - Young-Flash:find_self, r=lnicola

fix: find `Self` reference

took a lot of time to debug to find the problem, here should compare the actual `Adt` type

close rust-lang/rust-analyzer#12693

Author: bors

crates/ide-db/src/search.rs

@@ -584,7 +584,7 @@ impl<'a> FindUsages<'a> {
     ) -> bool {
         match NameRefClass::classify(self.sema, name_ref) {
             Some(NameRefClass::Definition(Definition::SelfType(impl_)))
-                if impl_.self_ty(self.sema.db) == *self_ty =>
+                if impl_.self_ty(self.sema.db).as_adt() == self_ty.as_adt() =>
             {
                 let FileRange { file_id, range } = self.sema.original_range(name_ref.syntax());
                 let reference = FileReference {

crates/ide/src/references.rs

@@ -683,6 +683,32 @@ enum Foo {
         );
     }
 
+    #[test]
+    fn test_self() {
+        check(
+            r#"
+struct S$0<T> {
+    t: PhantomData<T>,
+}
+
+impl<T> S<T> {
+    fn new() -> Self {
+        Self {
+            t: Default::default(),
+        }
+    }
+}
+"#,
+            expect![[r#"
+            S Struct FileId(0) 0..38 7..8
+
+            FileId(0) 48..49
+            FileId(0) 71..75
+            FileId(0) 86..90
+            "#]],
+        )
+    }
+
     #[test]
     fn test_find_all_refs_two_modules() {
         check(