Before submitting a PR, make sure tests pass:
bin/composer install
bin/phpunit
Documentation is built using Sphinx.
Make sure you have pip installed and then install the needed dependencies inside a virtualenv environment, in order not to pollute your system:
sudo pip install virtualenv
You also need to install Graphviz, which is used for generating graphs. It is mostly likely available through your package manager:
[macOS] brew install graphviz
[debian] sudo apt-get instal graphviz
Build the documentation with:
make docs
Alternatively, use sphinx-autobuild to watch changes and automatically refresh the browser:
venv/bin/sphinx-autobuild -E -B Resources/doc Resources/doc/_build