If the interview is for experience candidates, Then I suggest asking more towards edge cases, they should be able to know when their script will most likely fail and how to handle it.
For example in a userevent after submit, they should handle the context type delete, even though it might not affect any process but script might throw continuous errors bcz of it..
How a developer approaches the solution and how they structures the script/module matters. Whether a dev knows a specific type of script should be the basic requirement.