Contributing to Emacs

Emacs is a collaborative project and we encourage contributions from
anyone and everyone.  If you want to contribute in the way that will
help us most, we recommend (1) fixing reported bugs and (2)
implementing the feature ideas in etc/TODO.  However, if you think of
new features to add, please suggest them too -- we might like your
idea.  Porting to new platforms is also useful, when there is a new
platform, but that is not common nowadays.

For documentation on how to develop Emacs changes, refer to the Emacs
Manual and the Emacs Lisp Reference Manual (both included in the Emacs
distribution).  The web pages in http://www.gnu.org/software/emacs
contain additional information.

You may also want to submit your change so that can be considered for
inclusion in a future version of Emacs (see below).

If you don't feel up to hacking Emacs, there are many other ways to
help.  You can answer questions on the mailing lists, write
documentation, find and report bugs, contribute to the Emacs web
pages, or develop a package that works with Emacs.

Here are some style and legal conventions for contributors to Emacs:


o	Coding Standards

	Contributed code should follow the GNU Coding Standard.
	If it doesn't, we'll need to find someone to fix the code
	before we can use it.

	Emacs has certain additional style and coding conventions.

	Ref: http://www.gnu.org/prep/standards_toc.html
	Ref: GNU Coding Standards Info Manual


o	Copyright Assignment

	We can accept small changes without legal papers, and for
	medium-size changes a copyright disclaimer is ok too.  To
	accept substantial contributions from you, we need a copyright
	assignment form filled out and filed with the FSF.

	Contact us at emacs-devel@gnu.org to obtain the relevant
	forms.


o	Getting the Source Code

	The latest version of Emacs can be downloaded using CVS or
	Arch from the Savannah web site.  It is important to write
	your patch based on this version; if you start from an older
	version, your patch may be outdated when you write it, and
	maintainers will have hard time applying it.

	After you have downloaded the CVS source, you should read the
	file INSTALL.CVS for build instructions (they differ to some
	extent from a normal build).

	Ref: http://savannah.gnu.org/projects/emacs


o	Submitting Patches

	Every patch must have several pieces of information before we
	can properly evaluate it.

	* For bug fixes, a description of the bug and how your patch
	  fixes this bug.

	* For new features, a description of the feature and your
	  implementation.

	* A ChangeLog entry as plaintext (separate from the patch);
	  see the various ChangeLog files for format and content. Note
	  that, unlike some other projects, we do require ChangeLogs
	  also for documentation, i.e. Texinfo files.

	  Ref: "Change Log Concepts" node of the GNU Coding Standards
	  Info Manual, for how to write good log entries.

	* The patch itself.  If you are accessing the CVS repository
	  use "cvs update; cvs diff -cp"; else, use "diff -cp OLD NEW".
	  If your version of diff does not support these options, then
	  get the latest version of GNU Diff. 

	* We accept the patches as plain text (preferred for the
	  compilers themselves), MIME attachments (preferred for the
	  web pages), or as uuencoded gzipped text.

	When you have all these pieces, bundle them up in a mail message
	and send it to emacs-pretest-bug@gnu.org or emacs-devel@gnu.org.
	All subsequent discussion should also be sent to the mailing
	list.


o	Please reread your patch before submitting it.


o	If you send several unrelated changes together, we will
	ask you to separate them so we can consider each of the changes
	by itself.


o	Supplemental information for Emacs Developers:

	Once you become a frequent contributor to Emacs, we can
	consider giving you write access to the CVS repository.

	Discussion about Emacs development takes place on
	emacs-devel@gnu.org.

	Think carefully about whether your change requires updating the
	documentation.  If it does, you can either do this yourself or
	add an item to the NEWS file.

	If you document your change in NEWS, please mark the NEWS
	entry with the documentation status of the change: if you
	submit the changes for the manuals, mark it with "+++"; if it
	doesn't need to be documented, mark it with "---"; if it needs
	to be documented, but you didn't submit documentation changes,
	leave the NEWS entry unmarked.  (These marks are checked by
	the Emacs maintainers to make sure every change was reflected
	in the manuals.)

	The best way to understand Emacs Internals is to read the code,
	but the nodes "Tips" and "GNU Emacs Internals" in the Appendix
	of the Emacs Lisp Reference Manual may also help.

	The file etc/DEBUG describes how to debug Emacs bugs.

	Avoid using `defadvice' or `eval-after-load' for Lisp
	code to be included in Emacs.