Handle one more case where NamedTuple has a frozenset.

Author: paulsc

deepdiff/delta.py

@@ -719,7 +719,12 @@ def _do_set_or_frozenset_item(self, items, func):
             obj = self._get_elem_and_compare_to_old_value(
                 parent, path_for_err_reporting=path, expected_old_value=None, elem=elem, action=action, forced_old_value=set())
             new_value = getattr(obj, func)(value)
-            self._simple_set_elem_value(parent, path_for_err_reporting=path, elem=elem, value=new_value, action=action)
+            if hasattr(parent, '_fields') and hasattr(parent, '_replace'):
+                # Handle parent NamedTuple by creating a new instance with _replace(). Will not work with nested objects.
+                new_parent = parent._replace(**{elem: new_value})
+                self.root = new_parent
+            else:
+                self._simple_set_elem_value(parent, path_for_err_reporting=path, elem=elem, value=new_value, action=action)
 
     def _do_ignore_order_get_old(self, obj, remove_indexes_per_path, fixed_indexes_values, path_for_err_reporting):
         """

tests/test_delta.py

@@ -636,7 +636,15 @@ class Point(NamedTuple):
         delta = Delta(diff)
         assert p2 == p1 + delta
 
-
+    def test_namedtuple_frozenset_add_delta(self):
+        class Article(NamedTuple):
+            tags: frozenset
+        a1 = Article(frozenset(["a" ]))
+        a2 = Article(frozenset(["a", "b"]))
+        diff = DeepDiff(a1, a2)
+        delta = Delta(diff)
+        assert a2 == a1 + delta
+ 
 picklalbe_obj_without_item = PicklableClass(11)
 del picklalbe_obj_without_item.item