Sphinx Developer’s Guide

Abstract

This document describes the development process of Sphinx, a documentation system used by developers to document systems used by other developers to develop other systems that may also be documented using Sphinx.

The Sphinx source code is managed using Git and is hosted on GitHub.

git clone git://github.com/sphinx-doc/sphinx

Community

sphinx-users <sphinx-users@googlegroups.com>
Mailing list for user support.
sphinx-dev <sphinx-dev@googlegroups.com>
Mailing list for development related discussions.
#sphinx-doc on irc.freenode.net
IRC channel for development questions and user support.

Bug Reports and Feature Requests

If you have encountered a problem with Sphinx or have an idea for a new feature, please submit it to the issue tracker on GitHub or discuss it on the sphinx-dev mailing list.

For bug reports, please include the output produced during the build process and also the log file Sphinx creates after it encounters an unhandled exception. The location of this file should be shown towards the end of the error message.

Including or providing a link to the source files involved may help us fix the issue. If possible, try to create a minimal project that produces the error and post that instead.

Contributing to Sphinx

The recommended way for new contributors to submit code to Sphinx is to fork the repository on GitHub and then submit a pull request after committing the changes. The pull request will then need to be approved by one of the core developers before it is merged into the main repository.

  1. Check for open issues or open a fresh issue to start a discussion around a feature idea or a bug.
  2. If you feel uncomfortable or uncertain about an issue or your changes, feel free to email the sphinx-dev mailing list.
  3. Fork the repository on GitHub to start making your changes to the master branch for next major version, or X.Y branch for next minor version (see Branch Model).
  4. Write a test which shows that the bug was fixed or that the feature works as expected.
  5. Send a pull request and bug the maintainer until it gets merged and published. Make sure to add yourself to AUTHORS and the change to CHANGES.

Getting Started

These are the basic steps needed to start developing on Sphinx.

  1. Create an account on GitHub.

  2. Fork the main Sphinx repository (sphinx-doc/sphinx) using the GitHub interface.

  3. Clone the forked repository to your machine.

    git clone https://github.com/USERNAME/sphinx
    cd sphinx
    
  4. Checkout the appropriate branch.

    For changes that should be included in the next minor release (namely bug fixes), use the X.Y branch.

    git checkout X.Y
    

    For new features or other substantial changes that should wait until the next major release, use the master branch (see Branch Model for detail).

  5. Setup a virtual environment.

    This is not necessary for unit testing, thanks to tox, but it is necessary if you wish to run sphinx-build locally or run unit tests without the help of tox.

    virtualenv ~/.venv
    . ~/.venv/bin/activate
    pip install -e .
    
  6. Create a new working branch. Choose any name you like.

    git checkout -b feature-xyz
    
  7. Hack, hack, hack.

    For tips on working with the code, see the Coding Guide.

  8. Test, test, test.

    Testing is best done through tox, which provides a number of targets and allows testing against multiple different Python environments:

    • To list all possible targets:

      tox -av
      
    • To run unit tests for a specific Python version, such as 3.6:

      tox -e py36
      
    • To run unit tests for a specific Python version and turn on deprecation warnings on so they’re shown in the test output:

      PYTHONWARNINGS=all tox -e py36
      
    • To run code style and type checks:

      tox -e mypy
      tox -e flake8
      
    • Arguments to pytest can be passed via tox, e.g. in order to run a particular test:

      tox -e py36 tests/test_module.py::test_new_feature
      
    • To build the documentation:

      tox -e docs
      
    • To build the documentation in multiple formats:

      tox -e docs -- -b html,latexpdf
      
    • To run JavaScript tests with Karma, execute the following commands (requires Node.js):

      npm install
      npm run test
      

    You can also test by installing dependencies in your local environment.

    pip install .[test]
    

    New unit tests should be included in the tests directory where necessary:

    • For bug fixes, first add a test that fails without your changes and passes after they are applied.
    • Tests that need a sphinx-build run should be integrated in one of the existing test modules if possible. New tests that to @with_app and then build_all for a few assertions are not good since the test suite should not take more than a minute to run.
  9. Please add a bullet point to CHANGES if the fix or feature is not trivial (small doc updates, typo fixes). Then commit:

    git commit -m '#42: Add useful new feature that does this.'
    

    GitHub recognizes certain phrases that can be used to automatically update the issue tracker.

    For example:

    git commit -m 'Closes #42: Fix invalid markup in docstring of Foo.bar.'
    

    would close issue #42.

  10. Push changes in the branch to your forked repository on GitHub.

    git push origin feature-xyz
    
  11. Submit a pull request from your branch to the respective branch (master or X.Y).

  12. Wait for a core developer to review your changes.

Core Developers

The core developers of Sphinx have write access to the main repository. They can commit changes, accept/reject pull requests, and manage items on the issue tracker.

You do not need to be a core developer or have write access to be involved in the development of Sphinx. You can submit patches or create pull requests from forked repositories and have a core developer add the changes for you.

The following are some general guidelines for core developers:

  • Questionable or extensive changes should be submitted as a pull request instead of being committed directly to the main repository. The pull request should be reviewed by another core developer before it is merged.
  • Trivial changes can be committed directly but be sure to keep the repository in a good working state and that all tests pass before pushing your changes.
  • When committing code written by someone else, please attribute the original author in the commit message and any relevant CHANGES entry.

Locale updates

The parts of messages in Sphinx that go into builds are translated into several locales. The translations are kept as gettext .po files translated from the master template sphinx/locale/sphinx.pot.

Sphinx uses Babel to extract messages and maintain the catalog files. It is integrated in setup.py:

  • Use python setup.py extract_messages to update the .pot template.
  • Use python setup.py update_catalog to update all existing language catalogs in sphinx/locale/*/LC_MESSAGES with the current messages in the template file.
  • Use python setup.py compile_catalog to compile the .po files to binary .mo files and .js files.

When an updated .po file is submitted, run compile_catalog to commit both the source and the compiled catalogs.

When a new locale is submitted, add a new directory with the ISO 639-1 language identifier and put sphinx.po in there. Don’t forget to update the possible values for language in doc/config.rst.

The Sphinx core messages can also be translated on Transifex. There exists a client tool named tx in the Python package “transifex_client”, which can be used to pull translations in .po format from Transifex. To do this, go to sphinx/locale and then run tx pull -f -l LANG where LANG is an existing language identifier. It is good practice to run python setup.py update_catalog afterwards to make sure the .po file has the canonical Babel formatting.

Coding Guide

  • Try to use the same code style as used in the rest of the project. See the Pocoo Styleguide for more information.
  • For non-trivial changes, please update the CHANGES file. If your changes alter existing behavior, please document this.
  • New features should be documented. Include examples and use cases where appropriate. If possible, include a sample that is displayed in the generated output.
  • When adding a new configuration variable, be sure to document it and update sphinx/quickstart.py if it’s important enough.
  • Use the included utils/check_sources.py script to check for common formatting issues (trailing whitespace, lengthy lines, etc).
  • Add appropriate unit tests.

Debugging Tips

  • Delete the build cache before building documents if you make changes in the code by running the command make clean or using the sphinx-build -E option.

  • Use the sphinx-build -P option to run pdb on exceptions.

  • Use node.pformat() and node.asdom().toxml() to generate a printable representation of the document structure.

  • Set the configuration variable keep_warnings to True so warnings will be displayed in the generated output.

  • Set the configuration variable nitpicky to True so that Sphinx will complain about references without a known target.

  • Set the debugging options in the Docutils configuration file.

  • JavaScript stemming algorithms in sphinx/search/*.py (except en.py) are generated by this modified snowballcode generator. Generated JSX files are in this repository. You can get the resulting JavaScript files using the following command:

    npm install
    node_modules/.bin/grunt build # -> dest/*.global.js
    

Branch Model

Sphinx project uses following branches for developing.

master
Used for main development. All improvement and refactoring, bug fixes are allowed.
X.Y
Where X.Y is the MAJOR.MINOR release. Used to maintain current stable release. Only bug fixes and stable changes are allowed. Only the most recent stable release is currently retained. When a new version is released, the old release branch will be deleted and replaced by an equivalent tag.

Deprecating a feature

There are a couple reasons that code in Sphinx might be deprecated:

  • If a feature has been improved or modified in a backwards-incompatible way, the old feature or behavior will be deprecated.
  • Sometimes Sphinx will include a backport of a Python library that’s not included in a version of Python that Sphinx currently supports. When Sphinx no longer needs to support the older version of Python that doesn’t include the library, the library will be deprecated in Sphinx.

As the Deprecation policy describes, the first release of Sphinx that deprecates a feature (A.B) should raise a RemovedInSphinxXXWarning (where XX is the Sphinx version where the feature will be removed) when the deprecated feature is invoked. Assuming we have good test coverage, these warnings are converted to errors when running the test suite with warnings enabled:

pytest -Wall

Thus, when adding a RemovedInSphinxXXWarning you need to eliminate or silence any warnings generated when running the tests.

Deprecation policy

A feature release may deprecate certain features from previous releases. If a feature is deprecated in feature release 1.A, it will continue to work in all 1.A.x versions (for all versions of x) but raise warnings. Deprecated features will be removed in the first 1.B release, or 1.B.1 for features deprecated in the last 1.A.x feature release to ensure deprecations are done over at least 2 feature releases.

So, for example, if we decided to start the deprecation of a function in Sphinx 1.4:

  • Sphinx 1.4.x will contain a backwards-compatible replica of the function which will raise a RemovedInSphinx16Warning.
  • Sphinx 1.5 (the version that follows 1.4) will still contain the backwards-compatible replica.
  • Sphinx 1.6 will remove the feature outright.

The warnings are displayed by default. You can turn off display of these warnings with:

  • PYTHONWARNINGS= make html (Linux/Mac)
  • export PYTHONWARNINGS= and do make html (Linux/Mac)
  • set PYTHONWARNINGS= and do make html (Windows)

Unit Testing

Sphinx has been tested with pytest runner. Sphinx developers write unit tests using pytest notation. Utility functions and pytest fixtures for testing are provided in sphinx.testing. If you are a developer of Sphinx extensions, you can write unit tests with using pytest. At this time, sphinx.testing will help your test implementation.

How to use pytest fixtures that are provided by sphinx.testing? You can require 'sphinx.testing.fixtures' in your test modules or conftest.py files like this:

pytest_plugins = 'sphinx.testing.fixtures'

If you want to know more detailed usage, please refer to tests/conftest.py and other test_*.py files under tests directory.

Note

Prior to Sphinx - 1.5.2, Sphinx was running the test with nose.

New in version 1.6: sphinx.testing as a experimental.

New in version 1.8: Sphinx also runs JavaScript tests.