Exception : Call to a member function summarise() on null

Exception : Call to a member function summarise() on null

by Ulrike Albers -
Number of replies: 8

Hello,

I should have posted an answer in this discussion, but it is closed.

We use Moodle 3.6; in a quiz, there is a problem with the statistics: we get the following error:

Exception : Call to a member function summarise() on null

The same error is displayed when one clicks on recalculate grades. It is possible that the teacher modified some question after a students' attempt (I wonder how, though, as Moodle usually prevents us from doing that). Is there a way to access the statistics?

Thank you in advance!


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In reply to Ulrike Albers

Re: Exception : Call to a member function summarise() on null

by Tim Hunt -
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers
This looks like MDL-66095 (sorry, not fixed yet) although a temporary work-around was added in MDL-66115, so if you upgrade to the latest 3.6.x release, things should start working.

And, more generally, be very, very careful editing questions after students had attempted them.
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In reply to Tim Hunt

Re: Exception : Call to a member function summarise() on null

by Ulrike Albers -
Thank you very much for your answer Tim! I'm very sorry I forgot to subscribe to the discussion so I just saw it know. I will let teachers know.
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In reply to Tim Hunt

Re: Exception : Call to a member function summarise() on null

by heli g -
We are experiencing this issue on 3.5, but cannot identify which files were modified in the MDL-6611 temporary work-around.
Assistance would be greatly appreciated.
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In reply to heli g

Re: Exception : Call to a member function summarise() on null

by Tim Hunt -
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers
That is the wrong issue number. The right issue number is in my post above.

And, the code change for that fix is https://github.com/moodle/moodle/commit/39260e3eadc71613320d80b99c3d4352b9994e48
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In reply to Tim Hunt

Re: Exception : Call to a member function summarise() on null

by heli g -
Thank you so much Tim - that fixed it. You really are amazing!
(Apologies for the typo in the post above, I was indeed looking at MDL-66115)
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In reply to heli g

Re: Exception : Call to a member function summarise() on null

by heli g -
Just in case anyone else is as clueless as me, if you can't find a link to code updates in the tracker: Go to https://github.com/moodle/moodle and enter the issue number in the Search box. The link to the code change is under Commits.
It seems so obvious now, but not so much when I was panicking late last night... Thanks again for your prompt assistance Tim.
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In reply to heli g

Re: Exception : Call to a member function summarise() on null

by heli g -
The issue was identified because forum posts were not being emailed. It has temporarily been resolved by disabling \core\task\legacy_plugin_cron_task - but what effect will this have on Quizzes or any other mods that may be using legacy cron?
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In reply to heli g

Re: Exception : Call to a member function summarise() on null

by Tim Hunt -
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers
To be honest, I don't remember exactly what the situation was in Moodle 3.5.

There was a big push to get all the legacy cron converted to use the new scheduled task system (MDL-61164). Some of that was done for 3.5, but some of it was not finished until 3.7 (See the linked issues.)
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