Unit test mocking example in python

namer.py

def name_replay(we, they):
    return timestamp()+ '_' + we + '_vs_' + they

def timestamp():
    # not yet implemented
    return

output.txt

 [acoyle01] wtfpy > ll
total 16
drwxr-xr-x  2 acoyle users 4096 Nov 22 19:53 .
drwxr-xr-x 20 acoyle users 4096 Nov 22 19:38 ..
-rw-r--r--  1 acoyle users  131 Nov 22 19:45 namer.py
-rw-r--r--  1 acoyle users  731 Nov 22 19:50 test_namer.py
 [acoyle01] wtfpy > python3 test_namer.py -v
test_name_replay_mocked (__main__.TestNameReplay) ... ok
test_name_replay_with_decorator (__main__.TestNameReplay) ... ok

----------------------------------------------------------------------
Ran 2 tests in 0.001s

OK

test_namer.py

import unittest
from unittest.mock import MagicMock
from unittest.mock import patch

import namer

class TestNameReplay(unittest.TestCase):
    def test_name_replay_mocked(self):
        mock_timestamp = MagicMock()
        mock_timestamp.return_value = '202011221945'
        namer.timestamp = mock_timestamp
        name = namer.name_replay('packrat', 'jy')
        self.assertEqual(name, '202011221945_packrat_vs_jy')

    @patch('namer.timestamp')
    def test_name_replay_with_decorator(self, mock_timestamp):
        mock_timestamp.return_value = '202011221945'
        name = namer.name_replay('packrat', 'jy')
        self.assertEqual(name, '202011221945_packrat_vs_jy')

if __name__ == '__main__':
    unittest.main()