Copyright (C) 2006-2014 Free Software Foundation, Inc. See end for license conditions. 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 Emacs (to understand how to implement your desired change), refer to: - the Emacs Manual http://www.gnu.org/software/emacs/manual/emacs.html (info "(Emacs)Top") - the Emacs Lisp Reference Manual http://www.gnu.org/software/emacs/manual/elisp.html (info "(elisp)Top") - http://www.gnu.org/software/emacs - http://www.emacswiki.org/ There are many ways to contribute to Emacs: - implement a new feature, and submit a patch (see "Submitting Patches" below). - answer questions on the Emacs user mailing list https://lists.gnu.org/mailman/listinfo/help-gnu-emacs - write documentation, either on the wiki, or in the Emacs source repository (see "Submitting Patches" below) - find and report bugs; use M-x report-emacs-bug - check if existing bug reports are fixed in newer versions of Emacs http://debbugs.gnu.org/cgi/pkgreport.cgi?which=pkg&data=emacs - develop a package that works with Emacs, and publish it on your own or in Gnu ELPA (see admin/notes/elpa). Here are some style and legal conventions for contributors to Emacs: * Coding Standards Contributed code should follow the GNU Coding Standards (http://www.gnu.org/prep/standards/ - may also be available in info on your system). If it doesn't, we'll need to find someone to fix the code before we can use it. Emacs has additional style and coding conventions: - the "Tips" Appendix in the Emacs Lisp Reference http://www.gnu.org/software/emacs/manual/html_node/elisp/Tips.html (info "(elisp)Tips"). - Avoid using `defadvice' or `eval-after-load' for Lisp code to be included in Emacs. - Remove all trailing whitespace in all source and text files. - Emacs has no convention on whether to use tabs in source code; please don't change whitespace in the files you edit. - Use ?\s instead of ? in Lisp code for a space character. * Copyright Assignment The FSF (Free Software Foundation) is the copyright holder for GNU Emacs. The FSF is a nonprofit with a worldwide mission to promote computer user freedom and to defend the rights of all free software users. For general information, see the website http://www.fsf.org/ . Generally speaking, for non-trivial contributions to GNU Emacs we require that the copyright be assigned to the FSF. For the reasons behind this, see: http://www.gnu.org/licenses/why-assign.html . Copyright assignment is a simple process. Residents of some countries can do it entirely electronically. We can help you get started, and answer any questions you may have (or point you to the people with the answers), at the emacs-devel@gnu.org mailing list. (Please note: general discussion about why some GNU projects ask for a copyright assignment is off-topic for emacs-devel. See gnu-misc-discuss instead.) A copyright disclaimer is also a possibility, but we prefer an assignment. Note that the disclaimer, like an assignment, involves you sending signed paperwork to the FSF (simply saying "this is in the public domain" is not enough). Also, a disclaimer cannot be applied to future work, it has to be repeated each time you want to send something new. We can accept small changes (roughly, fewer than 15 lines) without an assignment. This is a cumulative limit (e.g. three separate 5 line patches) over all your contributions. * Getting the Source Code The current working version of the Emacs source code is stored in a git repository on the Savannah web site (http://savannah.gnu.org/projects/emacs). It is important to write your patch based on the current working version. If you start from an older version, your patch may be outdated (so that maintainers will have a hard time applying it), or changes in Emacs may have made your patch unnecessary. After you have downloaded the repository source, you should read the file INSTALL.REPO for build instructions (they differ to some extent from a normal build). * Submitting Patches Every patch must have several pieces of information before we can properly evaluate it. When you have all these pieces, bundle them up in a mail message and send it to the developers. Sending it to bug-gnu-emacs@gnu.org (which is the bug/feature list) is recommended, because that list is coupled to a tracking system that makes it easier to locate patches. If your patch is not complete and you think it needs more discussion, you might want to send it to emacs-devel@gnu.org instead. If you revise your patch, send it as a followup to the initial topic. ** Description For bug fixes, a description of the bug and how your patch fixes it. For new features, a description of the feature and your implementation. ** ChangeLog A ChangeLog entry as plaintext (separate from the patch). See the existing ChangeLog files for format and content. Note that, unlike some other projects, we do require ChangeLogs 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. http://www.gnu.org/prep/standards/html_node/Change-Log-Concepts.html When using git, commit messages should use ChangeLog format, with a single short line explaining the change, then an empty line, then unindented ChangeLog entries. (Essentially, a commit message should be a duplicate of what the patch adds to the ChangeLog files. We are planning to automate this better, to avoid the duplication.) You can use the Emacs functions log-edit-add-to-changelog or log-edit-insert-changelog to ease this process. ** The patch itself. If you are accessing the Emacs repository, make sure your copy is up-to-date (e.g. with 'git pull'). You can commit your changes to a private branch and generate a patch from the master version by using git format-patch master Or you can leave your changes uncommitted and use git diff With no repository, you can use diff -u OLD NEW ** Mail format. We prefer to get the patches as plain text, either inline (be careful your mail client does not change line breaks) or as MIME attachments. ** Please reread your patch before submitting it. ** Do not mix changes. If you send several unrelated changes together, we will ask you to separate them so we can consider each of the changes by itself. ** Do not make formatting changes. Making cosmetic formatting changes (indentation, etc) makes it harder to see what you have really changed. * Supplemental information for Emacs Developers. An "Emacs Developer" is someone who contributes a lot of code or documentation to the Emacs repository. ** Write access to the Emacs repository. Once you become a frequent contributor to Emacs, we can consider giving you write access to the version-control repository. Request access on the emacs-devel@gnu.org mailing list. ** Using the Emacs repository Emacs uses git for the source code repository. See http://www.emacswiki.org/emacs/GitQuickStartForEmacsDevs to get started, and http://www.emacswiki.org/emacs/GitForEmacsDevs for more advanced information. Alternately, see admin/notes/git-workflow. If committing changes written by someone else, make the ChangeLog entry in their name, not yours. git distinguishes between the author and the committer; use the --author option on the commit command to specify the actual author; the committer defaults to you. ** Changelog notes - Emacs generally follows the GNU coding standards when it comes to ChangeLogs: http://www.gnu.org/prep/standards/html_node/Change-Logs.html . One exception is that we still sometimes quote `like-this' (as the standards used to recommend) rather than 'like-this' (as they do now), because `...' is so widely used elsewhere in Emacs. - There are multiple ChangeLogs in the emacs source; roughly one per high-level directory. The ChangeLog entry for a commit belongs in the lowest ChangeLog that is higher than or at the same level as any file changed by the commit. - Preferred form for several entries with the same content: * help.el (view-lossage): * kmacro.el (kmacro-edit-lossage): * edmacro.el (edit-kbd-macro): Fix docstring, lossage is now 300 keys. (Rather than anything involving "ditto" and suchlike.) - In ChangeLog files, there is no standard or recommended way to identify revisions. One way to identify revisions is by quoting their summary line. Another is with an action stamp - an RFC3339 date followed by ! followed by the committer's email - for example, "2014-01-16T05:43:35Z!esr@thyrsus.com". Often, "my previous commit" will suffice. - There is no need to make separate change log entries for files such as NEWS, MAINTAINERS, and FOR-RELEASE, or to indicate regeneration of files such as 'configure'. "There is no need" means you don't have to, but you can if you want to. ** branches Development normally takes places on the trunk. Sometimes specialized features are developed on separate branches before possibly being merged to the trunk. Development is discussed on the emacs-devel mailing list. Sometime before the release of a new major version of Emacs a "feature freeze" is imposed on the trunk, to prepare for creating a release branch. No new features may be added to the trunk after this point, until the release branch is created. This freeze is announced on the emacs-devel mailing list, and not anywhere else. The trunk branch is named "master" in git; release branches are named "emacs-nn" where "nn" is the major version. You must follow emacs-devel to know exactly what kinds of changes are allowed on what branch at any time. Announcements about the freeze (and other important events) will contain "ANNOUNCE" in the subject. If you are fixing a bug that exists in the current release, be sure to commit it to the release branch; it will be merged to the master branch later. However, if you know that the change will be difficult to merge to the trunk (eg because the trunk code has changed a lot), you can apply the change to both trunk and branch yourself. Indicate in the release branch commit log that there is no need to merge the commit to the trunk; start the commit message with "Backport:". gitmerge.el will then exclude that commit from the merge to trunk. ** Other process information See all the files in admin/notes/* . In particular, see admin/notes/newfile, see admin/notes/repo. ** Emacs Mailing lists. Discussion about Emacs development takes place on emacs-devel@gnu.org. Bug reports and fixes, feature requests and implementations should be sent to bug-gnu-emacs@gnu.org, the bug/feature list. This is coupled to the tracker at http://debbugs.gnu.org . You can subscribe to the mailing lists, or see the list archives, by following links from http://savannah.gnu.org/mail/?group=emacs . ** Document your changes. Any change that matters to end-users should have an entry in etc/NEWS. Think about whether your change requires updating the documentation (both manuals and doc-strings). If you know it does not, mark the NEWS entry with "---". If you know that *all* the necessary documentation updates have been made, mark the entry with "+++". Otherwise do not mark it. ** Understanding Emacs Internals. 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. This file is part of GNU Emacs. GNU Emacs is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. GNU Emacs is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Emacs. If not, see . Local variables: mode: outline paragraph-separate: "[ ]*$" end: