Django admin list does Count query twice

Django Internals
6

I’m going back on this issue, and based on this helpful comment posted on the PR

I guess we could compare root_queryset.query.where to paginator’s queryset where

I think I managed to find a better solution:
The relevant if/else is now this:

        if not self.model_admin.show_full_result_count:
            full_result_count = None
        elif (
            self.has_active_filters
            or isinstance(self.root_queryset, Manager)
            or self.queryset.query.where
        ):
            # Get the total number of objects, with no admin filters applied.
            full_result_count = self.root_queryset.count()
        else:
            # If there are no filters, no need for an extra query.
            full_result_count = result_count

The reason for the isinstance check is because on this test the root_queryset is a custom Manager, which doesn’t have a query property, so in that case I’m assuming we need to redo the count. I don’t have the enough knowledge to know if that assumption makes sense.
I also don’t really know if it would be better to compare the root_queryset.query.where to the queryset.query.where rather than a boolean check on the queryset.query.where

Two other tests needed adjustment to adapt to the new query count. I’ve ran the entire suite in my local and everything seems to w

Now, since the original bug was closed as a wontfix, I don’t really know what’s the process to follow. Do I file a new bug or should the existing one be reopened?