# Contributing to imag

So you want to contribute to imag! Thank you, that's awesome!

All contributors agree to the
[developer certificate of origin](#developer-certificate-of-origin)
by contributing to imag.


## Without Github

Contributing without a github account is perfectly fine and actually encouraged
as we try to move away from github step by step.
Feel free to contact [us via our mailinglist](http://imag-pim.org/mailinglist/)
and/or submit patches via mail (use `git format-patch` and
`git send-email`, always add a cover letter to describe your submission).

Also ensure that each commit submitted via email has
[a "Signed-off-by: " line](https://stackoverflow.com/questions/1962094/what-is-the-sign-off-feature-in-git-for).
By adding that line, you agree to our
[developer certificate of origin](#developer-certificate-of-origin).
If you do not add the "Signed-off-by: " line, I reserve the right to kindly
reject your patch.

Once _I am_ okay with your patchset, I will
submit it as PR in the github repository (as long as we're using github),
so CI can test it.
I might come back to you if something broke in CI or someone has a suggestion
how to improve your PR. I will keep you as author of the commits.


## Finding an issue

Finding an issue is simple: We have
[a special label in our issues section](https://github.com/matthiasbeyer/imag/issues?q=is%3Aissue+is%3Aopen+label%3Acomplexity%2Feasy)
for easy-to-solve issues. You can start there, don't hesitate to ask questions
if you do not understand the issue comment!
If there are currently no issues with that tag, just browse the issues or the
code... you'll always find things to improve!

Also, if you've found bugs or outdated stuff in our documentation, feel free to
file issues about them or even better: Write a pull request to fix them!


## Prerequisites

The prerequisites are simple: `cargo` and `rustc` in current version (stable)
or newer (we do not use nighly features though).

Build dependencies for building are listed in the
[default.nix file](http://git.imag-pim.org/imag/tree/default.nix),
though you do not have to have the `nix` package manager installed to build
imag.
Everything else will be done by `cargo`.

Note that this software is targeted towards commandline linux users and we do
not aim to be portable to Windows or Mac OSX (though I wouldn't mind merging
patches for OS X compatibility).

If you want to build the documentation (you don't have to) you'll need:

* pandoc
* pandoc-citeproc
* texlive
* lmodern (font package)
* (gnu) make

All dependencies are installable with the nix package manager by using a
`nix-shell`, if you have the nix package manager installed on your system.


## Commit guidelines

Please don't refer to issues or PRs from inside a commit message, if possible.
Make sure your PR does not contain "Fixup" commits when publishing it, but feel
free to push "Fixup" commits in the review process. We will ask you to clean
your history before merging! If you're submitting via patch-mail, I will do the
fixup squashing myself. If it fails I will come back to you.

Make sure to prefix your commits with `"doc: "` if you change the documentation.
Do not change document and code in one commit, always separate them.

If your changes are user-visible (new commandline flags, other semantics in the
commandline, etc), make sure to add a note in the `CHANGELOG.md` file (in the
same commit if it is a simple change).
**If it is a bugfix**, do add the changelog entry in a new commit (best would
be: one commit for a testcase which shows the bug, one commit for the fix, more
if the fix is complicated, and one commit for the changelog entry).
Changelog entries for bug fixes should be extra commits, because backporting
bugfixes gets simpler this way.

We do not follow some official Rust styleguide for our codebase, but we try to
write minimal and readable code. 100 characters per line, as few lines as
possible, avoid noise in the codebase, ... you get it.

Not all of your commits have to be buildable. But your PR has to be before it
will be merged to master.


## Feature branches

Use feature branches. If you could name them "<module name>/<what you do>",
for example "libimagstore/add-debugging-calls", that would be awesome.


## Code of Conduct

We use the same
[code of conduct as the rust community does](https://www.rust-lang.org/conduct.html).

Basically: Be kind, encourage others to ask questions - you are encouraged to
ask questions as well!


## Developer Certificate of Origin

```
Developer Certificate of Origin
Version 1.1

Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
660 York Street, Suite 102,
San Francisco, CA 94110 USA

Everyone is permitted to copy and distribute verbatim copies of this
license document, but changing it is not allowed.


Developer's Certificate of Origin 1.1

By making a contribution to this project, I certify that:

(a) The contribution was created in whole or in part by me and I
    have the right to submit it under the open source license
    indicated in the file; or

(b) The contribution is based upon previous work that, to the best
    of my knowledge, is covered under an appropriate open source
    license and I have the right under that license to submit that
    work with modifications, whether created in whole or in part
    by me, under the same open source license (unless I am
    permitted to submit under a different license), as indicated
    in the file; or

(c) The contribution was provided directly to me by some other
    person who certified (a), (b) or (c) and I have not modified
    it.

(d) I understand and agree that this project and the contribution
    are public and that a record of the contribution (including all
    personal information I submit with it, including my sign-off) is
    maintained indefinitely and may be redistributed consistent with
    this project or the open source license(s) involved.
```