Some time ago, it when from using '0' for no-subcategories to blank.
Change to properly define '0' or '1', update old questions, and make
sure to fix newly restored questions.
The sequence of questions that made up a quiz used to be stored as a
comma-separated list in quiz.questions. Now the same information is
stored in the rows in the quiz_slots table. This is not just 'better' in
a database design sense, but it allows for the future changes we will
need as we enhance the quiz in the MDL-40987 epic.
Having changed the database structure, all the rest of the code needs to
be changed to account for it, and that is done here.
Note that there are not many unit tests for the changed bit. That is
because as part of MDL-40987 we will be changing the code further, and
we will add unit tests then.
This data should all have been upgraded when moving to Moodle 2.1. It
was only kept as a back-up, and now, after 3 years have past, we can
clean it up.
This parallels question_attempt->minfraction, which allows the
fractional mark to go below zere.
This is needed to allow the certainty-base marking behaviours to work
better.
1/ type/match/tests/walkthrough_test.php - tests are failing randomly, looks like some weird randomisation is going on there - see TODOs
2/ type/multianswer/tests/upgradelibnewqe_test.php contains invalid expected value - see TODO
This was one of those innocent seeming issues where, once you start
digging, you find a mess. In this case, the code that is now in
question_wizard_form::add_hidden_fields used to exist in four different
places, in four inconsistent versions. This is now all nicely
re-factored, and that solves the problem.
Along the way, I found and fixed some wrong string references in
qtype_random, and stripped out some unnecessary &s in function
declarations.
Marina Glancy