I'm looking for help with terminology to explain that a unit test failed because the test script itself has errors. The statement "this unit test failed because..." usually implies that the test script is correct and it's the function under test that is incorrect. I'm looking for the other way around.
Context: I'm grading a bunch of assignments in Python 3.x where students had to define some classes and subclasses while also providing the unit testing in Pytest. I would like to give succinct but correct feedback.