# Failed: [pytest] empty parameter set in 'test_parse' at tests/test_parse.py:12

- **ID:** `python/pytest-parametrize-empty-list`
- **Domain:** python
- **Category:** data_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

pytest.mark.parametrize received an empty list for argvalues, so pytest reports an empty parameter set and fails the test by default (controlled by empty_parameter_set_mark).

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 7.x | active | — | — |
| 8.x | active | — | — |

## Workarounds

1. **** (90% success)
   ```
   # pytest.ini
[pytest]
empty_parameter_set_mark = skip
   ```
2. **** (88% success)
   ```
   CASES = load_cases() or [pytest.param(None, marks=pytest.mark.skip('no cases'))]

@pytest.mark.parametrize('case', CASES)
def test_parse(case): ...
   ```

## Dead Ends

- **** — Loses parameterization entirely; the test now runs once with undefined arguments and fails differently. (70% fail)
- **** — Hides the fact that the data source is empty, which is often the actual bug worth surfacing. (65% fail)