Skip to main content

Unit test helpers

Project description


Unit Test Helpers (uth) is a simple library for Python containing some helper methods for unit testing.

I found myself writing a lot of setup code using unittest.mock.patch and unittest.TestCase.addCleanup:

class MyTestCase(unittest.TestCase):
    def setUp(self):
        patcher = unittest.mock.patch('module.function')

        # Or if there was many functions and/or objects to patch
        # something like:
        for patcher in (

Adding helper methods to TestCase classes (via mixin class) allows easier patching:

import unittest
import unittest.mock

import uth

def function_a():
    return None

class MyTestCase(unittest.TestCase, uth.MockMixin):
    def setUp(self):
        # The function function_a is immediately patched and patching is stopped
        # automatically after the test has run (using unittest.TestCase.addCleanup).
        mock = self.patched('{}.function_a'.format(__name__), return_value=self.sentinel.retval)

    def test_function_a(self):
        self.assertEqual(function_a(), self.sentinel.retval)

    def test_sentinel(self):
        self.assertEqual(self.sentinel.value, unittest.mock.sentinel.value)

    def test_mock(self):
        mock = self.mock(return_value=self.sentinel.retval)
        self.assertIsInstance(mock, unittest.mock.Mock)

The patched method is the only one that actually provides functionality not directly present in unittest.mock. The members mock, patch and sentinel are provided for convenience; you don’t need to import unittest.mock and you can access mock related functionality through self.



A mixin class for unittest.TestCase (or any other class from which you want to use Mock, sentinel and/or patch).

The following members are added:

  • ANY


  • sentinel (property)

    Access to unittest.mock.sentinel

  • call(*args, **kwargs)

  • mock(*args, **kwargs)

    Calls unittest.mock.Mock with given arguments

  • magic_mock(*args, **kwargs)

    Calls unittest.mock.MagicMock with given arguments

  • patch(*args, **kwargs)

    Calls unittest.mock.patch with given arguments

  • patched(*args, **kwargs)

    Calls unittest.mock.patch with given arguments, starts the returned patcher, registers stopping the patcher using self.addCleanup and returns the return value of patcher.start (the Mock object).

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for uth, version 1.1.1
Filename, size File type Python version Upload date Hashes
Filename, size uth-1.1.1-py3-none-any.whl (3.4 kB) File type Wheel Python version py3 Upload date Hashes View
Filename, size uth-1.1.1.tar.gz (2.7 kB) File type Source Python version None Upload date Hashes View

Supported by

Pingdom Pingdom Monitoring Google Google Object Storage and Download Analytics Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN DigiCert DigiCert EV certificate StatusPage StatusPage Status page