Add boilerplate for CLI tests

test/test_main.py

@@ -4,6 +4,7 @@
 import unittest
 import unittest.mock as mock
 import sys
+import os
 
 sys.path.append('..')
 
@@ -15,6 +16,16 @@ class MainTest(unittest.TestCase):
     Tests for main
     """
 
+    def setUp(self):
+        """
+        Defining the exitcodes
+        """
+
+        self.exit_0 = 0 << 8
+        self.exit_1 = 1 << 8
+        self.exit_2 = 2 << 8
+        self.exit_3 = 3 << 8
+
     def test_debugprint(self):
         with mock.patch('builtins.print') as mock_print:
             debugPrint(True, 'debug')
@@ -24,3 +35,10 @@ class MainTest(unittest.TestCase):
         with mock.patch('check_http_json.pprint') as mock_pprint:
             debugPrint(True, 'debug', True)
             mock_pprint.assert_called_once_with('debug')
+
+    def test_cli_without_params(self):
+
+        command = '/usr/bin/env python3 check_http_json.py > /dev/null 2>&1'
+        status = os.system(command)
+
+        self.assertEqual(status, self.exit_2)