# TypeError: argument of type 'NoneType' is not iterable when testing core **URL:** \ **Category:** Rasa Open Source\ **Tags:** testing\ **Created:** [October 22, 2021, 8:06pm UTC](https://forum.rasa.com/t/typeerror-argument-of-type-nonetype-is-not-iterable-when-testing-core/48683 "2021-10-22T20:06:10Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![shaysi](https://avatars.discourse-cdn.com/v4/letter/s/a698b9/32.png) [@shaysi](https://forum.rasa.com/u/shaysi)\ **Post date:** [October 22, 2021, 8:06pm UTC](https://forum.rasa.com/t/typeerror-argument-of-type-nonetype-is-not-iterable-when-testing-core/48683/1 "2021-10-22T20:06:10Z")
Trying to run `rasa test core --fail-on-prediction-errors --out results/results-core-test`, I receive this error: ```auto Traceback (most recent call last): File "/opt/venv/bin/rasa", line 8, in sys.exit(main()) File "/opt/venv/lib/python3.8/site-packages/rasa/ __main__.py", line 117, in main cmdline_arguments.func(cmdline_arguments) File "/opt/venv/lib/python3.8/site-packages/rasa/cli/test.py", line 133, in run_core_test test_core( File "/opt/venv/lib/python3.8/site-packages/rasa/model_testing.py", line 182, in test_core rasa.utils.common.run_in_loop( File "/opt/venv/lib/python3.8/site-packages/rasa/utils/common.py", line 296, in run_in_loop result = loop.run_until_complete(f) File "uvloop/loop.pyx", line 1456, in uvloop.loop.Loop.run_until_complete File "/opt/venv/lib/python3.8/site-packages/rasa/core/test.py", line 1041, in test story_evaluation, _, entity_results = await _collect_story_predictions( File "/opt/venv/lib/python3.8/site-packages/rasa/core/test.py", line 916, in _collect_story_predictions ) = await _predict_tracker_actions( File "/opt/venv/lib/python3.8/site-packages/rasa/core/test.py", line 785, in _predict_tracker_actions ) = _collect_action_executed_predictions( File "/opt/venv/lib/python3.8/site-packages/rasa/core/test.py", line 704, in _collect_action_executed_predictions if FormPolicy. __name__ in prediction.policy_name: TypeError: argument of type 'NoneType' is not iterable ``` I don’t know if it’s a bug or how to debug, if someone could help I appreciate. ---
**Author:** ![stephens](https://dub1.discourse-cdn.com/flex013/user_avatar/forum.rasa.com/stephens/32/1632_2.png) [@stephens](https://forum.rasa.com/u/stephens)\ **Post date:** [October 23, 2021, 8:53pm UTC](https://forum.rasa.com/t/typeerror-argument-of-type-nonetype-is-not-iterable-when-testing-core/48683/2 "2021-10-23T20:53:55Z")
Does `rasa data validate` report any issues? ---
**Author:** ![shaysi](https://avatars.discourse-cdn.com/v4/letter/s/a698b9/32.png) [@shaysi](https://forum.rasa.com/u/shaysi)\ **Post date:** [October 25, 2021, 4:35pm UTC](https://forum.rasa.com/t/typeerror-argument-of-type-nonetype-is-not-iterable-when-testing-core/48683/3 "2021-10-25T16:35:30Z")
Running that command I get: ```auto Traceback (most recent call last): File "/opt/venv/lib/python3.8/site-packages/rasa/shared/core/training_data/loading.py", line 113, in load_data_from_files steps = reader.read_from_file(story_file) File "/opt/venv/lib/python3.8/site-packages/rasa/shared/core/training_data/story_reader/yaml_story_reader.py", line 99, in read_from_file return self.read_from_string( File "/opt/venv/lib/python3.8/site-packages/rasa/shared/core/training_data/story_reader/yaml_story_reader.py", line 127, in read_from_string return self.read_from_parsed_yaml(yaml_content) File "/opt/venv/lib/python3.8/site-packages/rasa/shared/core/training_data/story_reader/yaml_story_reader.py", line 152, in read_from_parsed_yaml parser.parse_data(data) File "/opt/venv/lib/python3.8/site-packages/rasa/shared/core/training_data/story_reader/yaml_story_reader.py", line 220, in parse_data self._parse_plain_item(item) File "/opt/venv/lib/python3.8/site-packages/rasa/shared/core/training_data/story_reader/yaml_story_reader.py", line 250, in _parse_plain_item self._parse_step(step) File "/opt/venv/lib/python3.8/site-packages/rasa/shared/core/training_data/story_reader/yaml_story_reader.py", line 283, in _parse_step self._parse_slot(step) File "/opt/venv/lib/python3.8/site-packages/rasa/shared/core/training_data/story_reader/yaml_story_reader.py", line 478, in _parse_slot SlotSet.type_name, {slot: self._slot_default_value(slot)} File "/opt/venv/lib/python3.8/site-packages/rasa/shared/core/training_data/story_reader/yaml_story_reader.py", line 499, in _slot_default_value slot = next(slot for slot in self.domain.slots if slot.name == slot_name) StopIteration The above exception was the direct cause of the following exception: Traceback (most recent call last): File "/opt/venv/bin/rasa", line 8, in sys.exit(main()) File "/opt/venv/lib/python3.8/site-packages/rasa/ __main__.py", line 117, in main cmdline_arguments.func(cmdline_arguments) File "/opt/venv/lib/python3.8/site-packages/rasa/cli/data.py", line 248, in validate_files validator = rasa.utils.common.run_in_loop(Validator.from_importer(file_importer)) File "/opt/venv/lib/python3.8/site-packages/rasa/utils/common.py", line 296, in run_in_loop result = loop.run_until_complete(f) File "uvloop/loop.pyx", line 1456, in uvloop.loop.Loop.run_until_complete File "/opt/venv/lib/python3.8/site-packages/rasa/validator.py", line 52, in from_importer story_graph = await importer.get_stories() File "/opt/venv/lib/python3.8/site-packages/rasa/shared/importers/rasa.py", line 53, in get_stories return await utils.story_graph_from_paths( File "/opt/venv/lib/python3.8/site-packages/rasa/shared/importers/utils.py", line 25, in story_graph_from_paths story_steps = await loading.load_data_from_files( RuntimeError: coroutine raised StopIteration ``` ---
**Author:** ![stephens](https://dub1.discourse-cdn.com/flex013/user_avatar/forum.rasa.com/stephens/32/1632_2.png) [@stephens](https://forum.rasa.com/u/stephens)\ **Post date:** [October 25, 2021, 4:50pm UTC](https://forum.rasa.com/t/typeerror-argument-of-type-nonetype-is-not-iterable-when-testing-core/48683/4 "2021-10-25T16:50:01Z")
Take a look at this [issue](https://github.com/RasaHQ/rasa/issues/8379). Is your `domain.yml` in root and your training data in `/data`? You may need to use the command line options if you have a custom repo setup.