Version number is (as mentioned) 3.7, but this has been carrying on for a long time.
I'm pretty sure this is what happens in the background:
- Attempt one -> number is pushed to grade book
- New attempt is opened -> grade -1 is written to assign_grades for attempt 2. This of course is not copied to the grade book (a grade of minus 1 would be strange)
- From now on, the grade book only looks at the grade for the last attempt for this assignment. Which is attempt 2. But that currently has grade -1 so nothing happens to the grade book. The grade book is never monitoring what is entered in attempt 1 for the assignment, as it is irrelevant for the grade book: that should only store the grade with the highest attempt number
To me this looks like a bug... but it might be design, I don't know.
It could be fixed pretty easy if the grade book will always store the grade from the highest attempt except when the grade is minus 1, then the grade book should store the grade from the attempt before that.