diff --git a/pungi/phases/gather/sources/source_comps.py b/pungi/phases/gather/sources/source_comps.py
index b9992080..69ba9e3a 100644
--- a/pungi/phases/gather/sources/source_comps.py
+++ b/pungi/phases/gather/sources/source_comps.py
@@ -46,5 +46,5 @@ class GatherSourceComps(pungi.phases.gather.source.GatherSourceBase):
             comps.filter_groups(variant.groups)
 
         for i in comps.get_comps_groups():
-            groups.add(i.groupid)
+            groups.add(i)
         return set(), groups
diff --git a/pungi/wrappers/comps.py b/pungi/wrappers/comps.py
index 39e63e38..cc18a990 100644
--- a/pungi/wrappers/comps.py
+++ b/pungi/wrappers/comps.py
@@ -45,7 +45,8 @@ class CompsWrapper(object):
         self.comps_file = comps_file
 
     def get_comps_groups(self):
-        return self.comps.get_groups()
+        """Return a list of group IDs."""
+        return [group.groupid for group in self.comps.get_groups()]
 
     def write_comps(self, comps_obj=None, target_file=None):
         if not comps_obj: