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Mutation testing for Python

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|Python version| |Build Status| |Code Health| |Code Coverage| |Documentation|

Cosmic Ray: mutation testing for Python

"Four human beings -- changed by space-born cosmic rays into something more than merely human." — The Fantastic Four

Cosmic Ray is a mutation testing tool for Python 3.

It makes small changes to your source code, running your test suite for each one. Here's how the mutations look:

.. image:: docs/source/cr-in-action.gif



The easiest way to contribute is to use Cosmic Ray and submit reports for defects or any other issues you come across. Please see CONTRIBUTING.rst for more details.

.. |Python version| image:: :target: .. |Build Status| image:: :target: .. |Code Health| image:: :target: .. |Code Coverage| image:: :target: .. |Documentation| image:: :target: .. |fulldocumentation| replace:: Read the full documentation at readthedocs. .. fulldocumentation:

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