Add a case of no argument at all

Author: bact

tests/test_cli.py

@@ -14,13 +14,17 @@ def test_cli_main(self):
             __main__.main()
         self.assertEqual(ex.exception.code, 2)
 
-        self.assertIsNone(__main__.main(["thainlp", "data", "path"]))
+        with self.assertRaises((ArgumentError, SystemExit)):
+            self.assertIsNone(__main__.main(["thainlp"]))
 
         with self.assertRaises((ArgumentError, SystemExit)):
             self.assertIsNone(
                 __main__.main(["thainlp", "NOT_EXIST", "command"])
             )
 
+        self.assertIsNone(__main__.main(["thainlp", "data", "path"]))
+
+
     def test_cli_data(self):
         self.assertIsInstance(getattr(cli, "data"), ModuleType)