testfixtures 1.6.2

A collection of helpers and mock objects for unit tests and doc tests.

TestFixtures is a collection of helpers and mock objects that are useful when writing unit tests or doc tests.

It’s simple enough to get going with them, do one of the following:

• easy_install testfixtures

• add testfixtures as a required egg in your buildout config. You should only need to do this in the section that defines your test runner.

• download testfixtures.tar.gz from

  http://pypi.python.org/pypi/testfixtures

  You’ll then need to unpack it and do the usual python setup.py install

If you’re wondering why “yet another mock object library”, testing is often described as an art form and as such some styles of library will suite some people while others will suite other styles. This library was extracted from common test fixtures the author found himself repeating from package to packages and so decided to extract them into their own library and give them some tests of their own!

NB: TestFixtures own tests use the excellent Mock package:

http://pypi.python.org/pypi/mock/

While use of TestFixtures doesn’t require Mock to be installed, it’s highly recommended if you need mock objects for testing.

The available helpers and mock objects are listed below, for functional examples, see the contents of the tests folder.

Comparison

This class lets you instantiate placeholders that can be used to compared expected results with actual results where objects in the actual results do not support useful comparison. The comparision can be based just on the type of the object or on a partial set of the object’s attributes, both of which are particularly handy when comparing sequences returned from tested code.

compare

A replacement for assertEquals and the failUnless(x() is True) pattern. Gives more useful differences when the arguments aren’t the same, particularly for sequences and long strings.

diff

This function will compare two strings and give a unified diff of their comparison. Handy as a third parameter to unittest.TestCase.assertEquals.

generator

This function will return a generator that yields the arguments it was called with when the generator is iterated over.

LogCapture

This helper allows you to capture log messages for specified loggers in doctests.

log_capture

This decorator allows you to capture log messages for specified loggers for the duration of unittest methods.

replace

This decorator enables you to replace objects such as classes and functions for the duration of a unittest method. The replacements are removed regardless of what happens during the test.

Replacer

This helper enables you to replace objects such as classes and functions from within doctests and then restore the originals once testing is completed.

should_raise

This is a better version of assertRaises that lets you check the exception raised is not only of the correct type but also has the correct parameters.

TempDirectory

This helper will create a temporary directory for you using mkdtemp and provides a handy class method for cleaning all of these up.

tempdir

This decorator will create a temporary directory for the duration of the unit test and clear it up no matter the outcome of the test.

test_date

This is a handy class factory that returns datetime.date replacements that have a today method that gives repeatable, specifiable, testable dates.

test_datetime

This is a handy class factory that returns datetime.datetime replacements that have a now method that gives repeatable, specifiable, testable datetimes.

test_time

This is a handy replacement for time.time that gives repeatable, specifiable, testable times.

wrap

This is a generic decorator for wrapping method and function calls with a try-finally and having code executed before the try and as part of the finally.

Licensing

Copyright (c) 2008-2009 Simplistix Ltd

See license.txt for details.

Changes

1.6.2 (23 September 2009)

• changed Comparison to use __eq__ and __ne__ instead of the deprecated __cmp__

• documented that order matters when using Comparisons with objects that implement __eq__ themselves, such as instances of Django models.

1.6.1 (06 September 2009)

• @replace and Replacer.replace can now replace attributes that may not be present, provided the strict parameter is passed as False.

• should_raise now catches BaseException rather than Exception so raising of SystemExit and KeyboardInterrupt can be tested.

1.6.0 (09 May 2009)

• added support for using TempDirectory, Replacer and LogCapture as context managers for with statements

• fixed test failure in Python 2.6

1.5.4 (11 Feb 2009)

• fix bug where should_raise didn’t complain when no exception was raised but one was expected.

• clarified that the return of a should_raise call will be None in the event that an exception is raised by no expected exception is specified.

1.5.3 (17 Dec 2008)

• should_raise now supports methods other than __call__

1.5.2 (14 Dec 2008)

• added makedir and check_dir methods to TempDirectory and added support for sub directories to read and write

1.5.1 (12 Dec 2008)

• added path parameter to write method of TempDirectory so that the full path of the file written can be easilly obtained

1.5.0 (12 Dec 2008)

• added handy read and write methods to TempDirectory for creating and reading files in the temporary directory

• added support for rich comparison of objects that don’t support vars()

1.4.0 (12 Dec 2008)

• improved representation of failed Comparison

• improved representation of failed compare with sequences

1.3.1 (10 Dec 2008)

• fixed bug that occurs when directory was deleted by a test that use tempdir or TempDirectory

1.3.0 (9 Dec 2008)

• added TempDirectory helper

• added tempdir decorator

1.2.0 (3 Dec 2008)

• LogCaptures now auto-install on creation unless configured otherwise

• LogCaptures now have a clear method

• LogCaptures now have a class method uninstall_all that uninstalls all instances of LogCapture. Handy for a tearDown method in doctests.

1.1.0 (3 Dec 2008)

• add support to Comparisons for only comparing some attributes

• move to use zope.dottedname

1.0.0 (26 Nov 2008)

• Initial Release