id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
25307	Cannot use .annotate with conditional expressions	Jared Proffitt	nobody	"I am trying to create a query that first annotates a `Count`, then aggregates some `Sum`s together using `Case` objects. If I do the query without the annotate, everything is fine. If I do the query without any `Case` objects in the aggregate, everything is fine. But when they are both present I get this error:

{{{
 'WhereNode' object has no attribute 'get_source_expressions'
}}}

My query is something like this:

{{{
counts = models.Package.objects.annotate(
    used_count=Count('projects')
).distinct().aggregate(
    no_parent=Sum(Case(
        When(parent_id__isnull=True, then=1),
        default=0,
        output_field=IntegerField()
    ))
)
}}}

I would like to eventually add the `used_count` value in the aggregate, but this itself won't even run."	Bug	closed	Database layer (models, ORM)	dev	Normal	fixed		josh.smeaton@… matt@… Simon Charette newport.travis@…	Ready for checkin	1	0	0	1	0	0