chore: small improvement to "level" attribute in scope serializer

emeis/core/serializers.py

@@ -91,7 +91,13 @@ def get_level(self, obj):
         # Sometimes, the model object may come out of a non-django-tree-queries
         # QS, and thus would not have the `tree_*` attributes amended. Then we
         # need to go the "slow path"
-        return obj.ancestors().count()
+        if not obj.pk and obj.parent_id:
+            # unsaved object, sometimes used in unit tests etc
+            return self.get_level(obj.parent) + 1
+
+        if obj.parent_id:
+            return obj.ancestors().count()
+        return 0
 
     class Meta:
         model = Scope

emeis/core/tests/test_views.py

@@ -12,6 +12,8 @@
     HTTP_405_METHOD_NOT_ALLOWED,
 )
 
+from emeis.core.serializers import ScopeSerializer
+
 
 def test_me_200(db, acl, client):
     client.force_authenticate(user=acl.user)
@@ -332,3 +334,23 @@ def test_sorted_scopes_when_forced_language(
     ]
 
     assert received_names == ["eins", "zwei"]
+
+
+@pytest.mark.parametrize(
+    "has_parent, is_in_db, expect_level",
+    [
+        (False, False, 0),
+        (False, True, 0),
+        (True, False, 1),
+        (True, True, 1),
+    ],
+)
+def test_serializer_level(db, scope_factory, has_parent, is_in_db, expect_level):
+    scope = scope_factory(parent=scope_factory() if has_parent else None)
+    if not is_in_db:
+        scope.pk = None
+
+    ser = ScopeSerializer(instance=scope)
+
+    level = ser.data["level"]
+    assert level == expect_level