fix bug and refleak

Author: JelleZijlstra

Lib/test/test_type_annotations.py

@@ -838,7 +838,9 @@ def test_complex_comprehension_inlining_exec(self):
 
     def test_annotate_qualname(self):
         code = """
-        def f() -> None: pass
+        def f() -> None:
+            def nested() -> None: pass
+            return nested
         class Outer:
             x: int
             def method(self, x: int):
@@ -848,4 +850,5 @@ def method(self, x: int):
         method = ns["Outer"].method
         self.assertEqual(method.__annotate__.__qualname__, "Outer.method.__annotate__")
         self.assertEqual(ns["f"].__annotate__.__qualname__, "f.__annotate__")
+        self.assertEqual(ns["f"]().__annotate__.__qualname__, "f.<locals>.nested.__annotate__")
         self.assertEqual(ns["Outer"].__annotate__.__qualname__, "Outer.__annotate__")

Python/compile.c

@@ -290,9 +290,11 @@ compiler_set_qualname(compiler *c)
             }
         }
         if (u->u_ste->ste_function_name != NULL) {
+            PyObject *tmp = base;
             base = PyUnicode_FromFormat("%U.%U",
-                parent->u_metadata.u_qualname,
+                base,
                 u->u_ste->ste_function_name);
+            Py_DECREF(tmp);
             if (base == NULL) {
                 return ERROR;
             }