This has been generated running the following Sniffs, all
them part of the Moodle's CodeSniffer standard:
- PSR12.Functions.ReturnTypeDeclaration
- PSR12.Functions.NullableTypeDeclaration
- moodle.Methods.MethodDeclarationSpacing
- Squiz.Whitespace.ScopeKeywordSpacing
All them are, exclusively, about correct spacing, so the changes
are, all them, only white space changes.
Only exceptions to the above are 3 changes what were setting the
return type in a new line, and, when that happens, the closing
parenthesis (bracket) has to go to the same line than the colon.
Previously, quiz statistics processing happened on a scheduled task.
This task looked for all quizzes with completed attempts, then
determined if those quizzes had a statistics calculation that's newer
than the most recent attempt, then ran the statistics calculation if
needed. It was hard coded to stop processing after 1 hour.
The queries involved in determining which quizzes needed processing
weren't terribly efficient, and combined with the 1 hour limit this made
the statistics unusable on large sites, where they are the most useful.
This converts the scheduled task to an ad-hoc task, and uses an event
observer for mod_quiz\event\attempt_submitted to queue a task when
it is needed. This removes the need for a query to work out what needs
processing, and allows the task processing to be scaled up as needed.
It turns out that there are plugins which don't (currently)
clean up their question attempts when a context is deleted.
Therefore, we need to make Moodle core robust to that.
Previously, when a user viewed the question bank, if the quiz statistics
had not already been calculated, we would try to compute them there an then.
This could be very, very slow, leading to session lock problems.
Now, we never try to compute the statistics on the fly. Instead, we rely
on the existing \quiz_statistics\task\recalculate scheduled task to do it.
There is a new method on the column class, for the column to declare any
statistics it requires. The question then efficiently loads all those
statistics in one go, and makes them available as the columns are
rendererd, or do any subsequent processing.
