"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:

Read the full documentation at readthedocs._

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.