Nose of Yeti

This is a project to provide a Behaviour Driven Development style DSL (domain specific language) for python tests.

It uses the fact that you can register a codec that is able to modify a python file before executing it.

Using this we can make it so that when python imports a file with a particular encoding as the first line of the file (noseOfYeti looks for # coding: spec), it will be intercepted and the tokens in the file will be translated to something else before the import continues.

NoseOfYeti uses this technique to translate from the DSL it defines into python classes and functions that may be recognised by the Python Nose testing framework.

It was originally developed by Stephen Moore after borrowing the idea from a project by Fernando Meyer called Yeti


Note that it is recommended you remove .pyc of your noseOfYeti specs when you upgrade noseOfYeti. The python interpreter skips the translation process if it sees a .pyc file (unless the .py file has changed since the .pyc file was created). This means that any changes in the translation process won’t happen untill either the .pyc files are removed or all the .py files have been changed.

Made pytest support play nicer when running against a unittest suite

Added support for pytest.

The support means the spec codec is registered for you and nested describes will not run inherited tests.

Changed the license to MIT from GPL

NoseOfYeti now understands and respects the async keyword.

Only really useful if you use something like

Nose2 support!
Python3 Compatibility with the plugins
Fixed a problem with repeating tests in sub-describes

Added python3 support (based off the work by cwacek)

Use tox to run tests in python2 and python3 now

Updated pylint plugin - Unfortunately seems to cause a lot of “Final newline missing” however….

Added __only_run_tests_in_children__ functionality

Fixed ignore tests so they don’t inject a nose.SkipTest

Removed all reference to should_dsl (Except for the tests, I’ll change those another day)


No injected imports by default

And changed –noy-without-should-dsl and –noy-without-default-imports to –noy-with-should-dsl and –noy-with-default-imports

Can now set common settings in a config json file.
1.4.4 and 1.4.5
Minor fixes
Added wrapped-setup option to allow decorating before_each and after_each functions instead of inserting a super call into them.
pre 1.4.3
No Changelog was maintained.


Docs can now be found using the wonderful


Always use a virtualenv!:

$ mkvirtualenv noseOfYeti

$ cd /root/of/noseOfYeti
$ pip install -e .
$ pip install "noseOfYeti[tests]"
$ ./

Or just run tox:

$ tox

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