When ending an exam, warn about dirty invalid parts separately to unsubmitted empty parts

[christianp]

The problem is that students who have knowingly not answered part of the exam won't see that they have invalid answers to other parts.

[christianp]

Or, list the parts with unsubmitted answers.

[christianp]

Or give the confirm dialog some "warning" styling, to make it look different.

[Lycanic]

Looking at more detail at the 'end exam' prompt, it's very similar in all cases, but in fact doesn't currently prompt for invalid answers:

Fully complete exam:

Incomplete exam:

Exam with invalid answer:

A warning style and potentially more detail in the latter two cases would hopefully help to bypass any familiarity-based rapid click-throughs.