@c -*- coding: utf-8; mode: texinfo; -*-

@include included/helpus.itexi

@node Introduction to contributing
@chapter Introduction to contributing

This chapter presents a quick overview of ways that people can
help LilyPond.

@menu
* Help us::
* Overview of work flow::
* Mentors::
@end menu


@node Help us
@section Help us

@helpusNeed

@helpusTasks

@helpusProjects


@node Overview of work flow
@section Overview of work flow

@cartouche
@strong{Short summary for Unix developers}: source code is at
@uref{git://git.sv.gnu.org/lilypond.git}.  Documentation is built
with Texinfo, after pre-processing with @code{lilypond-book}.
Send well-formed patches to @email{lilypond-devel@@gnu.org}.
@end cartouche

Git is a @emph{version control system} that tracks the history of
a program's source code.  The LilyPond source code is maintained
as a Git repository, which contains:

@itemize
@item
all of the source files needed to build LilyPond, and

@item
a record of the entire history of every change made to every file
since the program was born.
@end itemize

The @q{official} LilyPond Git repository is hosted by the GNU
Savannah software forge at @uref{http://git.sv.gnu.org}.
Although, since Git uses a @emph{distributed} model, technically
there is no central repository.  Instead, each contributor keeps a
complete copy of the entire repository (about 116MB).

Changes made within one contributor's copy of the repository can
be shared with other contributors using @emph{patches}.  A patch
is a simple text file generated by the @command{git} program that
indicates what changes have been made (using a special format).
If a contributor's patch is approved for inclusion (usually
through the mailing list), someone on the current development team
will @emph{push} the patch to the official repository.

The Savannah software forge provides two separate interfaces for
viewing the LilyPond Git repository online: @emph{cgit} and
@emph{gitweb}.  The cgit interface should work faster than gitweb
in most situations, but only gitweb allows you to search through
the source code using @command{grep}, which you may find useful.
The cgit interface is at
@uref{http://git.sv.gnu.org/cgit/lilypond.git/} and the gitweb
interface is at
@uref{http://git.sv.gnu.org/gitweb/?p=lilypond.git}.

Git is a complex and powerful tool, but tends to be confusing at
first, particularly for users not familiar with the command line
and/or version control systems.  We have created the
@command{lily-git} graphical user interface to ease this
difficulty.

@emph{Compiling} (@q{building}) LilyPond allows developers to see
how changes to the source code affect the program itself.
Compiling is also needed to package the program for specific
operating systems or distributions.  LilyPond can be compiled from
a local Git repository (for developers), or from a downloaded
tarball (for packagers).  Compiling LilyPond is a rather involved
process, and most contributor tasks do not require it.

Contributors can contact the developers through the
@q{lilypond-devel} mailing list.  The mailing list archive is
located at
@uref{http://lists.gnu.org/archive/html/lilypond-devel/}.  If you
have a question for the developers, search the archives first to
see if the issue has already been discussed.  Otherwise, send an
email to @email{lilypond-devel@@gnu.org}.  You can subscribe to
the developers' mailing list here:
@uref{http://lists.gnu.org/mailman/listinfo/lilypond-devel}.

@warning{Contributors on Windows or MacOS X wishing to compile
code or documentation are strongly advised to use our Ubuntu
LilyPond Developer Remix, as discussed in @ref{Quick start}.}


@node Mentors
@section Mentors

We have a semi-formal system of mentorship, similar to the
medieval @qq{journeyman/master} training system.  New contributors
will have a dedicated mentor to help them @qq{learn the ropes}.

@warning{This is subject to the availability of mentors; certain
jobs have more potential mentors than others.}

@subheading Contributor responsibilities

@enumerate

@item
Ask your mentor which sections of the CG you should read.

@item
If you get stuck for longer than 10 minutes, ask your mentor.
They might not be able to help you with all problems, but we find
that new contributors often get stuck with something that could be
solved/explained with 2 or 3 sentences from a mentor.

@item
If you have been working on a task much longer than was originally
estimated, stop and ask your mentor.  There may have been a
miscommunication, or there may be some time-saving tips that could
vastly simply your task.

@item
Send patches to your mentor for initial comments.

@item
Inform your mentor if you're going to be away for a month, or if
you leave entirely.  Contributing to lilypond isn't for everybody;
just let your mentor know so that we can reassign that work to
somebody else.

@item
Inform your mentor if you're willing to do more work -- we always
have way more work than we have helpers available.  We try to
avoid overwhelming new contributors, so you'll be given less work
than we think you can handle.

@end enumerate


@subheading Mentor responsibilities

@enumerate

@item
Respond to questions from your contributor(s) promptly, even if
the response is just @qq{sorry, I don't know} or @qq{sorry, I'm
very busy for the next 3 days; I'll get back to you then}.  Make
sure they feel valued.

@item
Inform your contributor(s) about the expected turnaround for your
emails -- do you work on lilypond every day, or every weekend, or
what?  Also, if you'll be unavailable for longer than usual (say,
if you normally reply within 24 hours, but you'll be at a
conference for a week), let your contributors know.  Again, make
sure they feel valued, and that your silence (if they ask a
question during that period) isn't their fault.

@item
Inform your contributor(s) if they need to do anything unusual for
the builds, such as doing a @qq{make clean / doc-clean} or
switching git branches (not expected, but just in case...)

@item
You don't need to be able to completely approve patches.  Make
sure the patch meets whatever you know of the guidelines (for doc
style, code indentation, whatever), and then send it on to the
frog list or -devel for more comments.  If you feel confident
about the patch, you can push it directly (this is mainly intended
for docs and translations; code patches should almost always go to
-devel before being pushed).

@item
Keep track of patches from your contributor.  Either upload them
to Rietveld yourself, or help+encourage them to upload the patches
themselves.  When a patch is on Rietveld, it's your responbility
to get comments for it, and to add a link to the patch to the
google tracker.  (tag it @qq{patch-new}, or @qq{patch-review} if
you feel very confident in it)

@item
Encourage your contributor to review patches, particularly your
own!  It doesn't matter if they're not familiar with C++ / scheme
/ build system / doc stuff -- simply going through the process is
valuable.  Besides, anybody can find a typo!

@item
Contact your contributor at least once a week.  The goal is just
to get a conversation started -- there's nothing wrong with simply
copy&pasting this into an email:

@example
Hey there,

How are things going?  If you sent a patch and got a review, do
you know what you need to fix?  If you sent a patch but have no
reviews yet, do you know when you will get reviews?  If you are
working on a patch, what step(s) are you working on?
@end example


@end enumerate