Ticket #5383: formset-class-not-set.diff

django/contrib/admin/options.py

@@ -664 +664 @@
         self.admin_site = admin_site
         self.parent_model = parent_model
         self.opts = self.model._meta
+        self.formset_class = forms.inline_formset(parent_model, self.model, fk_name=self.fk_name, formfield_callback=self.formfield_for_dbfield, extra=self.extra)
         super(InlineModelAdmin, self).__init__()
 
     def formset_add(self, request):
@@ -681 +682 @@
             return self.fieldsets
         if self.fields:
             return [(None, {'fields': self.fields})]
-        fields = [f for f in self.formset_class(request).form_class.base_fields.keys()]
+        fields = [f for f in self.formset_class.form_class.base_fields.keys()]
         return [(None, {'fields': fields})]
 
 class StackedInline(InlineModelAdmin):