Metadata-Version: 1.1
Name: cosmic_ray
Version: 2.0.1
Summary: Mutation testing
Home-page: http://github.com/sixty-north/cosmic-ray
Author: Sixty North AS
Author-email: austin@sixty-north.com
License: MIT License
Description: [![Python version](https://img.shields.io/badge/Python_version-3.4+-blue.svg)](https://www.python.org/) [![Build Status](https://travis-ci.org/sixty-north/cosmic-ray.png?branch=master)](https://travis-ci.org/sixty-north/cosmic-ray) [![Code Health](https://landscape.io/github/sixty-north/cosmic-ray/master/landscape.svg?style=flat)](https://landscape.io/github/sixty-north/cosmic-ray/master) [![Documentation](https://readthedocs.org/projects/cosmic-ray/badge/?version=latest)](http://cosmic-ray.readthedocs.org/en/latest/)
        
        # 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.
        
        ## Cosmic Ray is still learning how to walk!
        
        At this time Cosmic Ray is young and incomplete. It doesn't support
        all of the mutations it should, its output format is crude, it only
        supports some forms of test discovery, it may fall over on exotic
        modules...[the list goes on and on](https://github.com/sixty-north/cosmic-ray/issues). Still,
        for the adventurous it *does* work. Hopefully things will improve
        fairly rapidly.
        
        And, of course, patches and ideas are welcome.
        
        ## The short version
        
        If you just want to get down to the business of finding and killing
        mutants, you still need to set a few things up.
        
        ### Install Cosmic Ray
        
        First install Cosmic Ray. You can do this with `pip`:
        
        ```
        pip install cosmic_ray
        ```
        
        or from source:
        
        ```
        python setup.py install
        ```
        
        We recommend installing Cosmic Ray into a virtual environment. Often it makes sense to
        install it into the virtual environment of the package you want to test.
        
        ### Create a session and run tests
        
        Now you're ready to start killing mutants. Cosmic Ray uses a notion of
        *sessions* to encompass a full mutation testing suite. Since mutation testing
        runs can take a long time, and since you might need to stop and start them,
        sessions store data about the progress of a run. The first step in a full
        testing run, then, is to initialize a session:
        
        ```
        cosmic-ray init --baseline=10 <session name> <top module name> -- <test directory>
        ```
        
        This will create a database file called `<session name>.json`. Once this is
        created, you can start executing tests with the `exec` command:
        
        ```
        cosmic-ray exec <session name>
        ```
        
        Unless there are errors, this won't print anything.
        
        ### View the results
        
        Once the execution is complete (i.e., all mutations have been performed and
        tested), you can see the results of your session with the `cr-report` command:
        
        ```
        cosmic-ray dump <session name> | cr-report
        ```
        
        This will print out a bunch of information about the work that was performed,
        including what kinds of mutants were created, which were killed, and
        – chillingly – which survived.
        
        ## Distributed testing with Celery
        
        By default Cosmic Ray does all of its testing locally and serially, running only
        one test suite at a time. This can be too slow for many real-world testing
        scenarios. To help speed things up, Cosmic Ray supports distributed mutation
        testing using [Celery](http://www.celeryproject.org/) to send work to more than
        one machine. This is more complex to set up, but it makes mutation testing
        practical for a wider range of projects.
        
        To run Cosmic Ray in distributed mode, you first need to
        install [RabbitMQ](https://www.rabbitmq.com/). Cosmic Ray uses this message
        queue (via Celery) to distribute testing tasks. Once installed, start the
        RabbitMQ server. This is very platform-specific, so see the instructions for
        RabbitMQ on how to do this.
        
        Once RabbitMQ is running, you need to start one or more Cosmic Ray worker tasks
        to listen for commmands on the queue. Start a worker like this:
        
        ```
        celery -A cosmic_ray.tasks.worker worker
        ```
        
        You can start as many workers as you want. Be aware that these workers - and the
        processes they spawn - need to be able to import the modules you want to test.
        As a result, you generally want to start them in the virtual environment into
        which you've installed Cosmic Ray.
        
        Also remember that the workers need to be able to find and execute the tests as
        expressed to the `init` command. In other words, if you used `cosmic-ray init .
        . . -- tests` to initialize a session, the test loader (whether local or
        distributed) will look for tests in the `test` directory. So you need to make
        sure that the worker processes are running in directory where this makes sense.
        
        Finally, once the worker(s) are running you need to use the `--dist` flag when
        you run `cosmic-ray exec`:
        ```
        cosmic-ray exec --dist
        ```
        
        Note that all of the other Cosmic Ray commands --- `init`, `report`, etc. ---
        don't need the `--dist` flag; only `exec` and `run` use it.
        
        **[Further documentation is available at readthedocs](http://cosmic-ray.readthedocs.org/en/latest/).**
        
Keywords: testing
Platform: any
Classifier: Development Status :: 4 - Beta
Classifier: Environment :: Console
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: MIT License
Classifier: Operating System :: OS Independent
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 3.4
Classifier: Programming Language :: Python :: 3.5
Classifier: Programming Language :: Python :: 3.6
Classifier: Topic :: Software Development :: Libraries :: Python Modules
Classifier: Topic :: Software Development :: Testing
