diff --git a/nixos/lib/tests/test_ini.nix b/nixos/lib/tests/test_ini.nix
index e0053115eeb32ade5d6a6216373792d082c66904..c9fb90b7a4d4059ce403f230e3a6731bd22595a5 100644
--- a/nixos/lib/tests/test_ini.nix
+++ b/nixos/lib/tests/test_ini.nix
@@ -56,4 +56,9 @@ ini:
   { expected = "x = 12345\n";
     expr = ini.oneConfigItemText "x" 12345;
   };
+
+  test_dotted_key =
+  { expected = "x.y = z\n";
+    expr = ini.oneConfigItemText "x.y" "z";
+  };
 }