Provide better feedback and safeguards when reassigning a copy to another student.
Reassigning copies from one student to another has a chance of irreversibly destroying information and requiring manual action. Right now it provides no information about it. I propose to tackle this in several steps:
- If a submission is marked as ungraded as a result of reassigning a copy, we should show a message saying so, and probably containing a link to approve the new grading for convenience.
- If feedback is merged in a nontrivial way, we should refuse to perform an action, and instead request for confirmation.
This is probably impact: medium and not impact: high because incorrectly reassigning exams happens seldom.