Race condition leading to `Argument should belong to the same JavaScript world as target object`

[aaronjensen]

We are occasionally seeing this error come from Ferrum:

Argument should belong to the same JavaScript world as target object

From what I can tell, it may have to do with how cuprite handles finding within elements. If the page navigates in the middle of a find (in between the time when the within is resolved in Ruby to when the find is done) then the crash occurs.

page.within(:css, ".some-class") do
  page.find(:css, ".some-other-class")
end

[emilkarl]

Did you solve this?

[aaronjensen]

No, we have tended to avoid within for this reason. I haven't looked into it recently as a result.

[markedmondson]

Just started seeing this occurring frequently, but with no obvious changes. We do use within quite a lot as above but it had been fine for months/years...

[route]

@markedmondson something has changed on the js side maybe?

[markedmondson]

@route I don't see anything immediately obvious but that's a good callout.

What's interesting is that it fails in CI (using CircleCI) only and not locally. Also it seems intermittent (so basically the worst kind!).

Edit: Got it - there was a Stimulus controller occasionally raising which seems to have caused this!

[route]

Intermittent issues like that often manifest themselves on CI due to its slowness. Lower memory ceiling, slower CPU and it fails more often in comparison to flying macbooks