Fix completions for super with multiple inheritance

Summary: Before this diff, we were not giving all the completions from ancestors with multiple inheritance. The fix is the same as D75792048.

Reviewed By: stroxler

Differential Revision: D80887987

fbshipit-source-id: 77e7f4d4cbc7fe6db5f835c39b6c86331f2e6a10

Author: samwgoldman

pyrefly/lib/alt/attr.rs

@@ -2135,6 +2135,22 @@ impl<'a, Ans: LookupAnswer> AnswersSolver<'a, Ans> {
         self.completions_mro(mro, expected_attribute_name, res)
     }
 
+    fn completions_super(
+        &self,
+        cls: &Class,
+        start_lookup_cls: &ClassType,
+        expected_attribute_name: Option<&Name>,
+        res: &mut Vec<AttrInfo>,
+    ) {
+        let mro = self.get_mro_for_class(cls);
+        let mro = mro
+            .ancestors_no_object()
+            .iter()
+            .skip_while(|ancestor| *ancestor != start_lookup_cls)
+            .map(|x| x.class_object());
+        self.completions_mro(mro, expected_attribute_name, res)
+    }
+
     fn completions_class_type(
         &self,
         cls: &ClassType,
@@ -2203,8 +2219,11 @@ impl<'a, Ans: LookupAnswer> AnswersSolver<'a, Ans> {
                 expected_attribute_name,
                 res,
             ),
-            AttributeBase::SuperInstance(class, _) => {
-                self.completions_class_type(class, expected_attribute_name, res)
+            AttributeBase::SuperInstance(start_lookup_cls, obj) => {
+                let cls = match obj {
+                    SuperObj::Instance(c) | SuperObj::Class(c) => c.class_object(),
+                };
+                self.completions_super(cls, start_lookup_cls, expected_attribute_name, res);
             }
             AttributeBase::ClassObject(class) => {
                 self.completions_class(class.class_object(), expected_attribute_name, res)

pyrefly/lib/test/lsp/completion.rs

@@ -1011,6 +1011,36 @@ Completion Results:
     );
 }
 
+#[test]
+fn dot_complete_super() {
+    let code = r#"
+class A:
+    x: int
+
+class B:
+    y: str
+
+class C(A, B):
+    def foo(self):
+        super().
+#               ^
+"#;
+    let report =
+        get_batched_lsp_operations_report_allow_error(&[("main", code)], get_default_test_report());
+    assert_eq!(
+        r#"
+# main.py
+10 |         super().
+                     ^
+Completion Results:
+- (Field) x: int
+- (Field) y: str
+"#
+        .trim(),
+        report.trim(),
+    );
+}
+
 #[test]
 fn import_completions_on_builtins() {
     let code = r#"