# Contributing to GAP
We invite everyone to contribute by submitting patches, pull requests, and
bug reports. We would like to make the contributing process as easy as
## Packages versus contributions to the "core" system
One way of contributing to GAP is to write a GAP package (see
<http://www.gap-system.org/Packages/packages.html>) and send it to us to
consider for redistribution with GAP. This is appropriate if your
contribution adds a body of functionality for some area of mathematics (or
some coherent batch of system functionality). A package is also appropriate
if you plan to continue to develop your code in the future. You will retain
control of your code and be recorded as author and maintainer of it.
Packages are not an appropriate way to release fixes or extremely small
changes, or to impose your own preferences for, for instance, how things
should be printed.
## Issue reporting and code contributions
* Before you report an issue, or wish to add functionality, please try
and check to see if there are existing
We do not want you wasting your time duplicating somebody else's work.
* For substantial changes it is also advisable to contact us before
you start work to discuss your ideas.
* You should be prepared to wait until your pull request or patch
has been discussed and authorized prior to its inclusion. We might
also ask for you to adapt your changes to make them suitable for
* To help increase the chance of your pull request being accepted:
* Run the tests.
* Update the documentation, tests, examples, guides, and whatever
else is affected by your contribution.
* Use appropriate code formatting for both C and GAP.
* *The Campsite Rule*
A basic rule when contributing to GAP is the **campsite rule**:
leave the codebase in better condition than you found it.
Please clean up any messes that you find, and don't
leave behind new messes for the next contributor.
## Making Changes
GAP development follows a straightforward branching model. We prefer using
the GitHub infrastructure. If you would like to contribute, but do not want
to create a GitHub account, see below for an alternative.
* Make sure you are familiar with [Git](http://git-scm.com/book)
* see for example the [Atlassian Git Tutorials](https://www.atlassian.com/git/tutorials/)
for an excellent introduction to Git.
* Make sure you have a [GitHub account](https://github.com/signup/free).
* Make sure you are familiar with [GAP](http://www.gap-system.org/).
* Fork our [main development repository](https://github.com/gap-system/gap) on github
* Clone your fork to a chosen directory on your local machine using HTTPS:
$ git clone https://github.com/<your github user name>/gap.git
* This will create a folder called `gap` (in the location where you ran `git
clone`) containing the source files, folders and the Git repository. The
clone automatically sets up a remote alias named `origin` pointing to your
fork on GitHub, which you can verify with:
$ git remote -v
* Add `gap-system/gap` as a remote upstream
$ git remote add upstream https://github.com/gap-system/gap.git
* Ensure your existing clone is up-to-date with current `HEAD` e.g.
$ git fetch upstream
$ git merge upstream/master
* Create and checkout onto a topic (or feature) branch on which to base your work.
* This is typically done from the local `master` branch.
* For your own sanity, please avoid working on the local `master` branch.
Instead, create a new branch for your work:
$ git branch fix/master/my_contrib master
$ git checkout fix/master/my_contrib
A shorter way of doing the above is
$ git checkout -b fix/master/my_contrib master
which creates the topic branch and checks out that branch immediately after.
* Make commits of logical units.
* Check for unnecessary whitespace with
$ git diff --check
* Make sure your commit messages are along the lines of:
Short (50 chars or less) summary of changes
More detailed explanatory text, if necessary. Wrap it to about 72
characters or so. In some contexts, the first line is treated as the
subject of an email and the rest of the text as the body. The blank
line separating the summary from the body is critical (unless you omit
the body entirely); tools like rebase can get confused if you run the
Further paragraphs come after blank lines.
- Bullet points are okay, too
- Typically a hyphen or asterisk is used for the bullet, preceded by a
single space, with blank lines in between, but conventions vary here
* Make sure you have added any necessary tests for your changes.
* Run all the tests to assure nothing else was accidentally broken.
$ make testinstall
$ make teststandard
* Push your changes to a topic branch in your fork of the repository.
$ git push origin fix/master/my_contrib
* Go to GitHub and submit a pull request to GAP.
From there you will have to wait on one of the GAP committers to respond to
the request. This response might be an accept or some
changes/improvements/alternatives will be suggested. We do not guarantee
that all requests will be accepted.
## Making changes without Github account
If you do not want to open a GitHub account you can still clone the GAP
repository like so:
git clone https://github.com/gap-system/gap.git
Make your changes and commits, create a patch containing the commits you
want to send, and use git's [`send-email` feature](http://git-scm.com/docs/git-send-email)
to email the patch to <email@example.com>. You can refer to
on how to do this.
## Additional Resources
* [GAP Tutorial](http://gap-system.org/Manuals/doc/tut/chap0.html)
* [GAP Manual](http://gap-system.org/Manuals/doc/ref/chap0.html)
* [GAP Homepage](http://www.gap-system.org/)
* [GAP on GitHub: Quickstart](https://github.com/gap-system/gap-git-cheat-sheet/raw/master/gap-git-cheat-sheet.pdf)
* [Atlassian Git Tutorials](https://www.atlassian.com/git/tutorials/)
* [Using Pull Requests](https://help.github.com/articles/using-pull-requests)
* [General GitHub Documentation](https://help.github.com/)
Heavily adapted from the contributing files from the
[Factory Girl Rails](https://github.com/thoughtbot/factory_girl_rails/blob/master/CONTRIBUTING.md),