Maintainer’s Guide

Git workflow

Our Git workflow is simple:

  • The master branch is always shippable.
  • Every feature and every non-trivial change goes through a pull request.

GitHub calls this the “GitHub Flow” and has a very nice visual guide for this model.

Branch rules

Our workflow implies a couple of rules about which branches to push code to:

  • Please do not commit directly to master unless it’s a trivial change, a safe refactoring, a small bug or spelling fix, etc. If in doubt please use a separate branch and open a pull request.
  • Please commit new features, larger changes and refactorings and updates to documentation to separate branches and open a pull request for review and discussion.

Important

When creating a new branch please use a descriptive name to communicate the purpose of the branch to other developers and maintainers. fix-bug-42 is not a great name, but 42-fix-void-function-error-in-error-list is.

If your branch addresses a specific Github issue please name your branch issue-description, where issue is the number of the Github issue without any prefix and description is the description of the branch. This convention helps us to link branches to issues and has the added bonus of automatically moving issues into “In progress” on our Waffle board.

We do not enforce these rules to give you the freedom to ignore them when need be, like in the case of a very urgent but non-trivial bug fix. But please do try to follow these rules most of the time as they help us to maintain a high code quality in master.

For maintainers these rules are relaxed: They may commit to any branch at any time. Nonetheless we also recommend that maintainers open pull requests for discussion.

Pull requests

Todo

Explain how to review and merge pull requests

Signatures for commits and tags

We sign all release tags as part of our Release process. Thus you need a GPG key pair for Git. Github provides a great guide which helps you to generate a key and to tell Git about your key. Please also add your key to your Github account.

We also recommend that you sign all your commits with your key. Again, Github provides a good guide to sign commits.

See also

Signing Your Work
For more information about signing commits and tags take a look at the section in the Git manual.

Tooling and Services

In addition to Github where we host code and do code reviews we use a bit of extra tooling and some 3rd party services for Flycheck:

  • ReadTheDocs hosts http://www.flycheck.org and automatically rebuilds it on every change. It works mostly automatically and requires little configuration.
  • Travis CI runs our tests after every push and for every pull request. It’s configured through .travis.yml.

All maintainers have administrative access to these services so in case of an issue just contact them.

Maintenance scripts

Administrative processes are tedious and time-consuming, so we try to automate as much as possible. The maint/ directory contains many scripts for this purpose. make -C maint/ help provides an overview over all administrative tasks.

Most of these scripts require Python 3.5 and additional Python libraries. On OS X it is recommended that you use Homebrew to install the latest Python version with brew install python3. On Linux you should be able to obtain Python 3.5 from the package manager of your distribution.

To install all required libraries run make -C maint init. We recommend that you use virtualenv to avoid a global installation of Python modules. make init will warn you if you do not.

Versioning and releases

We use a single continuously increasing version number for Flycheck. Breaking changes may occur at any point.

Please feel free to make a release whenever you think it’s appropriate. It’s generally a good idea to release when

  • you fixed an important bug that affects many users,
  • there are a couple of new syntax checkers available,
  • there’s a major new feature in master,
  • etc.

In doubt just make a release. We aim to release early and frequently. If anything breaks anything we can just publish another release afterwards.

Release process

First, check that

  1. you are on master,
  2. your working directory is clean, i.e. has no uncommitted changes or untracked files,
  3. all commits are pushed,
  4. and Travis CI passes for the latest commit on master.

If all is good a new release is a simple as

$ make -C maint release

This runs the release script in maint/release.py. If any of the above requirements isn’t met the release script will signal an error and abort.

The release script bumps the version number, commits and tags a new release, and pushes it to Github.

Note

The tag is signed; you must configure Git for signing commits and tags before you make a release the first time. After pushing the new release to Github, the script bumps the version number again, to the next snapshot, and commits the changes again.

Once the script is completed please

  1. Edit the release information on Github and add a short summary about the release. Don’t forget to add a link to the complete changelog and upload the package TAR file.
  2. Enable the new release on the ReadTheDocs versions dashboard.
  3. Announce the new release in our Gitter channel, on emacs_flycheck Twitter and wherever else you see fit.