learnr parse error trailing garbage part 2

I want to re-open this issue: learnr parse error trailing garbage

To recap I'm using a package of learnr tutorials for teaching that I wrote (https://github.com/profandyfield/discovr ).

Some students are (again) getting the following error:

Error: parse error: trailing garbage

          ":{},"value":["0.10.1"]}]}]} {"type":"list","attributes":{},

                     (right here) ------^

Execution halted

We have students who, for example, load a tutorial successfully using the RStudio tutorials pane, but then next time they load it they get this error. Based on the previous version of this post I'm assuming it's an error with the html renedering and if we (a) delete the html of the problematic tutorial from the package library on their system, or (b) force a reinstall (which would also clear the html files) the problem goes away. However, it can come back (for the same student).

We can't see any consistent predictors of when it happens or for whom. It feels impossible to debug but I also don't really understand the process of what happens when someone clicks the 'start tutorial' button (other than it reneders my RMD into a tutortial ... or how it uses a stored html file when a tutorial starts or how a stored html might become corrupt.

I would really appreciate some pointers about why this might be happening - like, some options to explore or some better understanding of the rendering process and why it might fail when it has succeeded before. Could this be down to user input in a previous session using the tutorial? Could it be to do with strange text in my hints? Is there something I can do within the tutorial to prevent it (I currently don't error catch any code that students type into exercises). Any useful pointers?

1 Like

I would recommend engaging with the folks here :
Issues · rstudio/learnr (github.com)

Yeah, I hadn't done that because I wasn't sure it constitutes an issue, but you've given me confidence to take the plunge!