diff --git a/test/test_cli.py b/test/test_cli.py
index 7a5fc0d..648dd6e 100644
--- a/test/test_cli.py
+++ b/test/test_cli.py
@@ -85,7 +85,9 @@ class TestCLI:
         """Test the extended version information"""
         result = self.env.run("python-escpos", "version_extended")
         assert not result.stderr
-        # TODO test output
+        assert escpos.__version__ in result.stdout
+        # test that additional information on e.g. Serial is printed
+        assert "Serial" in result.stdout
 
     @pytest.mark.skip(
         reason="disable this test as it is not that easy anymore to predict the outcome of this call"