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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:

docs/source/cr-in-action.gif

Read the full documentation at readthedocs.

Contributing

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.

Release files for cosmic-ray 8.7.0

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for cosmic-ray 8.7.0
File Size Uploaded
cosmic_ray-8.7.0.tar.gz 1.7 MB Details

Built distribution (wheel)

Table of built distributions (wheels) for cosmic-ray 8.7.0
File Interpreter ABI Platform
cosmic_ray-8.7.0-py3-none-any.whl Python 3 none any Details

Total release size:1.7 MB

Release files / cosmic_ray-8.7.0.tar.gz

Download URL cosmic_ray-8.7.0.tar.gz
Size 1.7 MB
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Release files / cosmic_ray-8.7.0-py3-none-any.whl

Download URL cosmic_ray-8.7.0-py3-none-any.whl
Size 62.3 kB
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Uploaded via twine/7.0.0 CPython/3.13.14

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PyPI verified that this artifact, at this checksum, originated from the publisher listed below.

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8.7.0 This release

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