diff --git a/test/test_osbuild.py b/test/test_osbuild.py
index 0edd6675..56a5fb01 100644
--- a/test/test_osbuild.py
+++ b/test/test_osbuild.py
@@ -81,7 +81,7 @@ class TestDescriptions(unittest.TestCase):
         index = osbuild.meta.Index(os.curdir)
 
         modules = []
-        for klass in ("Stage", "Assembler"):
+        for klass in ("Stage", "Assembler", "Source"):
             mods = index.list_modules_for_class(klass)
             modules += [(klass, module) for module in mods]