Deduplicate tuple indices for completion

crates/ide-completion/src/completions/dot.rs

@@ -113,8 +113,12 @@ fn complete_fields(
  }
  }
  for (i, ty) in receiver.tuple_fields(ctx.db).into_iter().enumerate() {
- // Tuple fields are always public (tuple struct fields are handled above).
- tuple_index(acc, i, ty);
+ // Tuples are always the last type in a deref chain, so just check if the name is
+ // already seen without inserting into the hashset.
+ if !seen_names.contains(&hir::Name::new_tuple_field(i)) {
+ // Tuple fields are always public (tuple struct fields are handled above).
+ tuple_index(acc, i, ty);
+ }
  }
  }
 }
@@ -720,6 +724,28 @@ fn test(a: A) {
  );
  }
 
+ #[test]
+ fn test_tuple_struct_deref_to_tuple_no_same_index() {
+ check(
+ r#"
+//- minicore: deref
+struct A(u8);
+impl core::ops::Deref for A {
+ type Target = (u16, u32);
+ fn deref(&self) -> &Self::Target { loop {} }
+}
+fn test(a: A) {
+ a.$0
+}
+"#,
+ expect![[r#"
+ fd 0 u8
+ fd 1 u32
+ me deref() (use core::ops::Deref) fn(&self) -> &<Self as Deref>::Target
+ "#]],
+ );
+ }
+
  #[test]
  fn test_completion_works_in_consts() {
  check(