unittest2

unittest2 is a backport of unittest, with improved API and better assertions than in previous Python versions.

Installation

$ bin/python -m pip install unittest2

Example

We want to test the following add method:

def add(a, b):
    return a + b

Then we import the module under the name unittest to make it easier to port code to newer versions of the module in the future:

import unittest2 as unittest

class TestNotebook(unittest.TestCase):
    def test_add(self):
        self.assertEqual(add(2, 2), 5)

unittest.main(argv=[''], verbosity=2, exit=False)

test_add (__main__.TestNotebook) ... FAIL

======================================================================
FAIL: test_add (__main__.TestNotebook)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/var/folders/f8/0034db6d78s5r6m34fxhpk7m0000gp/T/ipykernel_69328/3137592767.py", line 6, in test_add
AssertionError: 4 != 5

----------------------------------------------------------------------
Ran 1 test in 0.002s

FAILED (failures=1)

<unittest2.main.TestProgram at 0x7f957c80a8e0>

This way, if you move to a newer Python version and no longer need the unittest2 module, you can simply change the import in your test module without having to change any further code.