Instantsearch.js: Missing last hit

[SchmidtDawid]

Describe the bug 🐛
Sometimes after search last page is empty. For example i got 145 hits, 24 hits per page. It is 24*6+1. On last page should be 1 hit but its 0.

To Reproduce 🔍
Steps to reproduce the behavior:

1. search
2. go to last page
3. page is emtpy

Expected behavior 💭
1 hit on last page
Screenshots 🖥
https://imgur.com/gallery/37DERj3
Edit:
another query with this bug:
https://imgur.com/a/eylyCKz

Environment:
everywhere ;)

Additional context
We realize we have QR on this query.
https://imgur.com/a/L2dCCfG
on querys without query rules everything is fine.

[bobylito]

Thanks for opening this issue.

What happens if you deactivate the query rule?

[SchmidtDawid]

After remove QR we've got 6 full pages (144 hits instead 145).

[bobylito]

Is the result promoted by the query rule part of the result set? What's the behaviour on the dashboard? Is it possible to have access to a live example?

[SchmidtDawid]

It seems yes. For example we have query with 144 hits and 24 hits per page. We've got 6 full pages then. If we add QR to this query then we'he got 145 hits. It makes 7 pages but last page is empty.
I cant give you live eqample becouse we have big product rotation and it can be out of date after few minutes.

[bobylito]

There is something weird. We're digging :)

[clement-leprovost]

Hello @SchmidtDawid, Clément from Algolia's search engine team here... :)

There is indeed a bug. Thanks for reporting it! 👍

FYI, it only happens on "big enough" indices (it needs incremental building to be triggered). Anyway, the cause is understood. A fix will come soon... but bear in mind that we need to deploy it on all Algolia machines before it is available. I'll update this thread when it's done.

[bobylito]

Thanks @clement-leprovost for the update. Since it's not an instantsearch.js related issue I will close this ticket for now :)