Pynguin

Pynguin (IPA: ˈpɪŋɡuiːn), the PYthoN General UnIt test geNerator, is a tool that allows developers to generate unit tests automatically.

Testing software is often considered to be a tedious task. Thus, automated generation techniques have been proposed and mature tools exist—for statically typed languages, such as Java. There is, however, no fully-automated tool available that produces unit tests for general-purpose programs in a dynamically typed language. Pynguin is, to the best of our knowledge, the first tool that fills this gap and allows the automated generation of unit tests for Python programs.

Internal Pipeline Status

Attention

Please Note:

Pynguin executes the module under test! As a consequence, depending on what code is in that module, running Pynguin can cause serious harm to your computer, for example, wipe your entire hard disk! We recommend running Pynguin in an isolated environment; use, for example, a Docker container to minimize the risk of damaging your system.

Pynguin is only a research prototype! It is not tailored towards production use whatsoever. However, we would love to see Pynguin in a production-ready stage at some point; please report your experiences in using Pynguin to us.

Prerequisites

Before you begin, ensure you have met the following requirements:

You have installed Python 3.10 (we have not yet tested with Python 3.11, there might be some problems due to changed internals regarding the byte-code instrumentation).

Attention: Pynguin now requires Python 3.10! Older versions are no longer supported!
You have a recent Linux/macOS/Windows machine.

Please consider reading the online documentation to start your Pynguin adventure.

Installing Pynguin

Pynguin can be easily installed using the pip tool by typing:

pip install pynguin

Make sure that your version of pip is that of a supported Python version, as any older version is not supported by Pynguin!

Using Pynguin

Before you continue, please read the quick start guide

Pynguin is a command-line application. Once you installed it to a virtual environment, you can invoke the tool by typing pynguin inside this virtual environment. Pynguin will then print a list of its command-line parameters.

A minimal full command line to invoke Pynguin could be the following, where we assume that a project foo is located in /tmp/foo, we want to store Pynguin's generated tests in /tmp/testgen, and we want to generate tests using a whole-suite approach for the module foo.bar (wrapped for better readability):

pynguin \
  --project-path /tmp/foo \
  --output-path /tmp/testgen \
  --module-name foo.bar

Please find a more detailed example in the quick start guide.

Using Parameter Control

To run parameter control we can extend the example command above as the following:

pynguin \
  --project-path /tmp/foo \
  --output-path /tmp/testgen \
  --module-name foo.bar \
  --algorithm DYNAMOSA_RL \
  --tuning_parameters Population,CrossoverRate,TournamentSize
  --update_frequency 10 \
  --plateau_length 5 \

--algorithm sets the test generation algorithm (GA) to be used. DYNAMOSA_RL is the only algorithm that currently supports parameter control.
--tuning_parameters defines which parameter(s) should be controlled. Formatted as a comma-separated list.
--update_frequency controls how many test generation iterations should surpass between each subsequent parameter value update.
--plateau_length controls how many test generation iterations must surpass before the parameter control is enabled, set to 0 for instant start.

The parameters available for control are the following: ChangeParameterProbability, ChromosomeLength, CrossoverRate, Elite, NONE, Population, RandomPerturbation, StatementInsertionProbability, TestChangeProbability, TestDeleteProbability, TestInsertProbability, TestInsertionProbability, TournamentSize

Contributing to Pynguin

For the development of Pynguin you will need the poetry dependency management and packaging tool. To start developing, follow these steps:

Clone the repository
Change to the pynguin folder: cd pynguin
Create a virtual environment and install dependencies using poetry: poetry install
Make your changes
Run make check to verify that your changes pass all checks

Please see the poetry documentation for more information on this tool.

Contributors

Pynguin is developed at the Chair of Software Engineering II of the University of Passau.

Maintainer: Stephan Lukasczyk

Contributors:

Development using PyCharm.

If you want to use the PyCharm IDE you have to set up a few things:

Import pynguin into PyCharm.
Let PyCharm configure configure a virtual environment using poetry.
Set the default test runner to pytest
Set the DocString format to Google

License

This project is licensed under the terms of the MIT License. Pynguin was using the GNU Lesser General Public License (LGPL) until version 0.29.0, its licence was changed with version 0.30.0.

henkejson/pynguin-adaptive-parameter-control