Development

Getting started

Pharaoh is an open source project initiated by Infineon Technologies and we welcome contributions of all forms. The sections below will help you get started with development, testing, and documentation. This document is meant to get you setup to work on Pharaoh and to act as a guide and reference to the development setup. If you face any issues during this process, please create an issue about it on the issue tracker.

Setup

To work on it, you’ll need:

  • Source code: available on GitHub. You can use git to clone the repository:

    git clone https://github.com/Infineon/pharaoh-dev.git
cd pharaoh-dev

  • Python interpreter: We recommend using CPython. You can use this guide to set it up.

  • tox: to automatically get the projects development dependencies and run the test suite. We recommend installing it using pipx.

Running from source tree

The easiest way to do this is to generate a development environment:

tox devenv -e py venv

This will install a virtualenv using the same Python version as under which tox is installed. Alternatively you can specify a specific version of Python by using the pyNN format, such as: py311, etc.

tox devenv -e py311 venv

Set venv/Scripts/python.exe (Windows) or venv/bin/python (Linux) as project interpreter in your IDE and you’re good to go.

See also

tox devenv

Running tests

Pharaoh’s tests are written using the pytest test framework. tox is used to automate the setup and execution of Pharaoh’s tests.

To run tests locally execute:

tox -e py

This will run the test suite for the same Python version as under which tox is installed. Alternatively you can specify a specific version of Python by using the pyNN format, such as: py38, pypy3, etc.

tox has been configured to forward any additional arguments it is given to pytest. This enables the use of pytest’s rich CLI. As an example, you can select tests using the various ways that pytest provides:

# Using markers
tox -e py -- -m "not slow"
# Using keywords
tox -e py -- -k "test_extra"

Running linters and code formatters

Pharaoh uses pre-commit for managing linting and formatting of the codebase. pre-commit performs various checks on all files in Pharaoh and uses tools that help following a consistent code style within the codebase. To execute the pre-commit hooks manually execute:

tox -e fix

Code style guide

  • First and foremost, the linters configured for the project must pass; this generally means following PEP-8 rules, as codified by: ruff, ruff-format.

  • The supported Python versions (and the code syntax to use) are listed in the pyproject.toml file in the project/requires-python entry.

  • All code (tests too) must be type annotated as much as required by mypy. Check this using tox -e type.

  • We use a line length of 120.

  • All function (including test) names must follow PEP-8, so they must be fully snake cased. All classes are upper camel-cased.

  • Prefer f-strings instead of the str.format method.

  • Tests should contain as little information as possible but do use descriptive variable names within it.

Building documentation

Pharaoh’s documentation is built using Sphinx. The documentation is written in reStructuredText. To build it locally, run:

tox -e docs

The built documentation can be found in the dist/docs folder and may be viewed by opening index.html within that folder.

Contributing

Submitting pull requests

Submit pull requests (PRs) against the main branch, providing a good description of what you’re doing and why. You must have legal permission to distribute any code you contribute to Pharaoh and it must be available under the MIT License. Provide tests that cover your changes and run the tests locally first. Pharaoh supports multiple Python versions and operating systems. Any pull request must consider and work on all these platforms.

Pull requests should be small to facilitate review. Keep them self-contained, and limited in scope. Studies have shown that review quality falls off as patch size grows. In particular, pull requests must not be treated as “feature branches”, with ongoing development work happening within the PR. Instead, the feature should be broken up into smaller, independent parts which can be reviewed and merged individually.

Additionally, avoid including “cosmetic” changes to code that is unrelated to your change, as these make reviewing the PR more difficult. Examples include re-flowing text in comments or documentation, or addition or removal of blank lines or whitespace within lines. Such changes can be made separately, as a “formatting cleanup” PR, if needed.

Automated testing

All pull requests and merges to the main branch are tested using GitHub Actions (configured by matrix_tests.yml file inside the .github/workflows directory). You can find the status and the results to the CI runs for your PR on GitHub’s Web UI for the pull request. You can also find links to the CI services’ pages for the specific builds in the form of “Details” links, in case the CI run fails and you wish to view the output.

To trigger CI to run again for a pull request, you can close and open the pull request or submit another change to the pull request. If needed, project maintainers can manually trigger a restart of a job/build.

Changelog entries

The changelog.rst file is currently manually curated and all relevant changes must be accompanied by a changelog entry. To add an entry to the changelog, first you need to have created an issue describing the change you want to make. A pull request itself may function as such, but it is preferred to have a dedicated issue (for example, in case the PR ends up rejected due to code quality reasons).

There is no need to create an issue for trivial changes, e.g. for typo fixes.

Contents of a changelog entry

The content of this file is reStructuredText formatted text that will be used as the content of the changelog entry. You do not need to reference the issue or PR numbers here as towncrier will automatically add a reference to all of the affected issues when rendering the changelog.

In order to maintain a consistent style in the changelog.rst file, it is preferred to keep the entries to the point, in sentence case, shorter than 120 characters and in an imperative tone – an entry should complete the sentence This change will …. In rare cases, where one line is not enough, use a summary line in an imperative tone followed by a blank line separating it from a description of the feature/change in one or more paragraphs, each wrapped at 120 characters. Remember that a changelog entry is meant for end users and should only contain details relevant to an end user.

Creating a new release

Releases are currently created using GitHub’s release functionality.

Prior to creating a release on GitHub make sure the target version in the changelog is correct and then draft a new release with the target version number according to Semantic Versioning.

Current maintainers