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diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches
index 72741ebda1..e8ad978824 100644
--- a/Documentation/SubmittingPatches
+++ b/Documentation/SubmittingPatches
@@ -1,57 +1,5 @@
-Checklist (and a short version for the impatient):
-
- Commits:
-
- - make commits of logical units
- - check for unnecessary whitespace with "git diff --check"
- before committing
- - do not check in commented out code or unneeded files
- - the first line of the commit message should be a short
- description (50 characters is the soft limit, see DISCUSSION
- in git-commit(1)), and should skip the full stop
- - the body should provide a meaningful commit message, which:
- - uses the imperative, present tense: "change",
- not "changed" or "changes".
- - includes motivation for the change, and contrasts
- its implementation with previous behaviour
- - add a "Signed-off-by: Your Name <you@example.com>" line to the
- commit message (or just use the option "-s" when committing)
- to confirm that you agree to the Developer's Certificate of Origin
- - make sure that you have tests for the bug you are fixing
- - make sure that the test suite passes after your commit
-
- Patch:
-
- - use "git format-patch -M" to create the patch
- - do not PGP sign your patch
- - do not attach your patch, but read in the mail
- body, unless you cannot teach your mailer to
- leave the formatting of the patch alone.
- - be careful doing cut & paste into your mailer, not to
- corrupt whitespaces.
- - provide additional information (which is unsuitable for
- the commit message) between the "---" and the diffstat
- - if you change, add, or remove a command line option or
- make some other user interface change, the associated
- documentation should be updated as well.
- - if your name is not writable in ASCII, make sure that
- you send off a message in the correct encoding.
- - send the patch to the list (git@vger.kernel.org) and the
- maintainer (gitster@pobox.com) if (and only if) the patch
- is ready for inclusion. If you use git-send-email(1),
- please test it first by sending email to yourself.
- - see below for instructions specific to your mailer
-
-Long version:
-
-I started reading over the SubmittingPatches document for Linux
-kernel, primarily because I wanted to have a document similar to
-it for the core GIT to make sure people understand what they are
-doing when they write "Signed-off-by" line.
-
-But the patch submission requirements are a lot more relaxed
-here on the technical/contents front, because the core GIT is
-thousand times smaller ;-). So here is only the relevant bits.
+Here are some guidelines for people who want to contribute their code
+to this software.
(0) Decide what to base your work on.
@@ -78,6 +26,10 @@ change is relevant to.
wait until some of the dependent topics graduate to 'master', and
rebase your work.
+ - Some parts of the system have dedicated maintainers with their own
+ repositories (see the section "Subsystems" below). Changes to
+ these parts should be based on their trees.
+
To find the tip of a topic branch, run "git log --first-parent
master..pu" and look for the merge commit. The second parent of this
commit is the tip of the topic branch.
@@ -90,7 +42,10 @@ your commit head. Instead, always make a commit with complete
commit message and generate a series of patches from your
repository. It is a good discipline.
-Describe the technical detail of the change(s).
+Give an explanation for the change(s) that is detailed enough so
+that people can judge if it is good thing to do, without reading
+the actual patch text to determine how well the code does what
+the explanation promises to do.
If your description starts to get too long, that's a sign that you
probably need to split up your commit to finer grained pieces.
@@ -99,54 +54,115 @@ help reviewers check the patch, and future maintainers understand
the code, are the most beautiful patches. Descriptions that summarise
the point in the subject well, and describe the motivation for the
change, the approach taken by the change, and if relevant how this
-differs substantially from the prior version, can be found on Usenet
-archives back into the late 80's. Consider it like good Netiquette,
-but for code.
-
-Oh, another thing. I am picky about whitespaces. Make sure your
+differs substantially from the prior version, are all good things
+to have.
+
+Make sure that you have tests for the bug you are fixing. See
+t/README for guidance.
+
+When adding a new feature, make sure that you have new tests to show
+the feature triggers the new behavior when it should, and to show the
+feature does not trigger when it shouldn't. After any code change, make
+sure that the entire test suite passes.
+
+If you have an account at GitHub (and you can get one for free to work
+on open source projects), you can use their Travis CI integration to
+test your changes on Linux, Mac (and hopefully soon Windows). See
+GitHub-Travis CI hints section for details.
+
+Do not forget to update the documentation to describe the updated
+behavior and make sure that the resulting documentation set formats
+well. It is currently a liberal mixture of US and UK English norms for
+spelling and grammar, which is somewhat unfortunate. A huge patch that
+touches the files all over the place only to correct the inconsistency
+is not welcome, though. Potential clashes with other changes that can
+result from such a patch are not worth it. We prefer to gradually
+reconcile the inconsistencies in favor of US English, with small and
+easily digestible patches, as a side effect of doing some other real
+work in the vicinity (e.g. rewriting a paragraph for clarity, while
+turning en_UK spelling to en_US). Obvious typographical fixes are much
+more welcomed ("teh -> "the"), preferably submitted as independent
+patches separate from other documentation changes.
+
+Oh, another thing. We are picky about whitespaces. Make sure your
changes do not trigger errors with the sample pre-commit hook shipped
in templates/hooks--pre-commit. To help ensure this does not happen,
run git diff --check on your changes before you commit.
-(1a) Try to be nice to older C compilers
+(2) Describe your changes well.
+
+The first line of the commit message should be a short description (50
+characters is the soft limit, see DISCUSSION in git-commit(1)), and
+should skip the full stop. It is also conventional in most cases to
+prefix the first line with "area: " where the area is a filename or
+identifier for the general area of the code being modified, e.g.
+
+ . archive: ustar header checksum is computed unsigned
+ . git-cherry-pick.txt: clarify the use of revision range notation
+
+If in doubt which identifier to use, run "git log --no-merges" on the
+files you are modifying to see the current conventions.
-We try to support a wide range of C compilers to compile
-git with. That means that you should not use C99 initializers, even
-if a lot of compilers grok it.
+The body should provide a meaningful commit message, which:
-Also, variables have to be declared at the beginning of the block
-(you can check this with gcc, using the -Wdeclaration-after-statement
-option).
+ . explains the problem the change tries to solve, iow, what is wrong
+ with the current code without the change.
-Another thing: NULL pointers shall be written as NULL, not as 0.
+ . justifies the way the change solves the problem, iow, why the
+ result with the change is better.
+ . alternate solutions considered but discarded, if any.
-(2) Generate your patch using git tools out of your commits.
+Describe your changes in imperative mood, e.g. "make xyzzy do frotz"
+instead of "[This patch] makes xyzzy do frotz" or "[I] changed xyzzy
+to do frotz", as if you are giving orders to the codebase to change
+its behaviour. Try to make sure your explanation can be understood
+without external resources. Instead of giving a URL to a mailing list
+archive, summarize the relevant points of the discussion.
-git based diff tools (git, Cogito, and StGIT included) generate
-unidiff which is the preferred format.
+
+(3) Generate your patch using Git tools out of your commits.
+
+Git based diff tools generate unidiff which is the preferred format.
You do not have to be afraid to use -M option to "git diff" or
"git format-patch", if your patch involves file renames. The
receiving end can handle them just fine.
-Please make sure your patch does not include any extra files
-which do not belong in a patch submission. Make sure to review
+Please make sure your patch does not add commented out debugging code,
+or include any extra files which do not relate to what your patch
+is trying to achieve. Make sure to review
your patch after generating it, to ensure accuracy. Before
sending out, please make sure it cleanly applies to the "master"
branch head. If you are preparing a work based on "next" branch,
that is fine, but please mark it as such.
-(3) Sending your patches.
+(4) Sending your patches.
+
+Learn to use format-patch and send-email if possible. These commands
+are optimized for the workflow of sending patches, avoiding many ways
+your existing e-mail client that is optimized for "multipart/*" mime
+type e-mails to corrupt and render your patches unusable.
-People on the git mailing list need to be able to read and
+People on the Git mailing list need to be able to read and
comment on the changes you are submitting. It is important for
a developer to be able to "quote" your changes, using standard
e-mail tools, so that they may comment on specific portions of
-your code. For this reason, all patches should be submitted
-"inline". WARNING: Be wary of your MUAs word-wrap
+your code. For this reason, each patch should be submitted
+"inline" in a separate message.
+
+Multiple related patches should be grouped into their own e-mail
+thread to help readers find all parts of the series. To that end,
+send them as replies to either an additional "cover letter" message
+(see below), the first patch, or the respective preceding patch.
+
+If your log message (including your name on the
+Signed-off-by line) is not writable in ASCII, make sure that
+you send off a message in the correct encoding.
+
+WARNING: Be wary of your MUAs word-wrap
corrupting your patch. Do not cut-n-paste your patch; you can
lose tabs that way if you are not careful.
@@ -170,7 +186,11 @@ message starts, you can put a "From: " line to name that person.
You often want to add additional explanation about the patch,
other than the commit message itself. Place such "cover letter"
-material between the three dash lines and the diffstat.
+material between the three-dash line and the diffstat. For
+patches requiring multiple iterations of review and discussion,
+an explanation of changes between each iteration can be kept in
+Git-notes and inserted automatically following the three-dash
+line via `git format-patch --notes`.
Do not attach the patch as a MIME attachment, compressed or not.
Do not let your e-mail client send quoted-printable. Do not let
@@ -198,23 +218,29 @@ patch, format it as "multipart/signed", not a text/plain message
that starts with '-----BEGIN PGP SIGNED MESSAGE-----'. That is
not a text/plain, it's something else.
-Unless your patch is a very trivial and an obviously correct one,
-first send it with "To:" set to the mailing list, with "cc:" listing
+Send your patch with "To:" set to the mailing list, with "cc:" listing
people who are involved in the area you are touching (the output from
"git blame $path" and "git shortlog --no-merges $path" would help to
-identify them), to solicit comments and reviews. After the list
-reached a consensus that it is a good idea to apply the patch, re-send
-it with "To:" set to the maintainer and optionally "cc:" the list for
-inclusion. Do not forget to add trailers such as "Acked-by:",
-"Reviewed-by:" and "Tested-by:" after your "Signed-off-by:" line as
-necessary.
+identify them), to solicit comments and reviews.
+
+After the list reached a consensus that it is a good idea to apply the
+patch, re-send it with "To:" set to the maintainer [*1*] and "cc:" the
+list [*2*] for inclusion.
+
+Do not forget to add trailers such as "Acked-by:", "Reviewed-by:" and
+"Tested-by:" lines as necessary to credit people who helped your
+patch.
+ [Addresses]
+ *1* The current maintainer: gitster@pobox.com
+ *2* The mailing list: git@vger.kernel.org
-(4) Sign your work
+
+(5) Sign your work
To improve tracking of who did what, we've borrowed the
"sign-off" procedure from the Linux kernel project on patches
-that are being emailed around. Although core GIT is a lot
+that are being emailed around. Although core Git is a lot
smaller project it is a good discipline to follow it.
The sign-off is a simple line at the end of the explanation for
@@ -242,17 +268,17 @@ pretty simple: if you can certify the below:
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.
+ (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.
then you just add a line saying
- Signed-off-by: Random J Developer <random@developer.example.org>
+ Signed-off-by: Random J Developer <random@developer.example.org>
-This line can be automatically added by git if you run the git-commit
+This line can be automatically added by Git if you run the git-commit
command with the -s option.
Notice that you can place your own Signed-off-by: line when
@@ -266,7 +292,7 @@ don't hide your real name.
If you like, you can put extra tags at the end:
-1. "Reported-by:" is used to to credit someone who found the bug that
+1. "Reported-by:" is used to credit someone who found the bug that
the patch attempts to fix.
2. "Acked-by:" says that the person who is more familiar with the area
the patch attempts to modify liked the patch.
@@ -281,6 +307,26 @@ You can also create your own tag or use one that's in common usage
such as "Thanks-to:", "Based-on-patch-by:", or "Mentored-by:".
------------------------------------------------
+Subsystems with dedicated maintainers
+
+Some parts of the system have dedicated maintainers with their own
+repositories.
+
+ - git-gui/ comes from git-gui project, maintained by Pat Thoyts:
+
+ git://repo.or.cz/git-gui.git
+
+ - gitk-git/ comes from Paul Mackerras's gitk project:
+
+ git://ozlabs.org/~paulus/gitk
+
+ - po/ comes from the localization coordinator, Jiang Xin:
+
+ https://github.com/git-l10n/git-po/
+
+Patches to these parts should be based on their trees.
+
+------------------------------------------------
An ideal patch flow
Here is an ideal patch flow for this project the current maintainer
@@ -305,7 +351,7 @@ suggests to the contributors:
spend their time to improve your patch. Go back to step (2).
(4) The list forms consensus that the last round of your patch is
- good. Send it to the list and cc the maintainer.
+ good. Send it to the maintainer and cc the list.
(5) A topic branch is created with the patch and is merged to 'next',
and cooked further and eventually graduates to 'master'.
@@ -325,59 +371,70 @@ Know the status of your patch after submission
tell you if your patch is merged in pu if you rebase on top of
master).
-* Read the git mailing list, the maintainer regularly posts messages
+* Read the Git mailing list, the maintainer regularly posts messages
entitled "What's cooking in git.git" and "What's in git.git" giving
the status of various proposed changes.
-------------------------------------------------
-MUA specific hints
+--------------------------------------------------
+GitHub-Travis CI hints
-Some of patches I receive or pick up from the list share common
-patterns of breakage. Please make sure your MUA is set up
-properly not to corrupt whitespaces. Here are two common ones
-I have seen:
+With an account at GitHub (you can get one for free to work on open
+source projects), you can use Travis CI to test your changes on Linux,
+Mac (and hopefully soon Windows). You can find a successful example
+test build here: https://travis-ci.org/git/git/builds/120473209
+
+Follow these steps for the initial setup:
+
+ (1) Fork https://github.com/git/git to your GitHub account.
+ You can find detailed instructions how to fork here:
+ https://help.github.com/articles/fork-a-repo/
-* Empty context lines that do not have _any_ whitespace.
+ (2) Open the Travis CI website: https://travis-ci.org
-* Non empty context lines that have one extra whitespace at the
- beginning.
+ (3) Press the "Sign in with GitHub" button.
-One test you could do yourself if your MUA is set up correctly is:
+ (4) Grant Travis CI permissions to access your GitHub account.
+ You can find more information about the required permissions here:
+ https://docs.travis-ci.com/user/github-oauth-scopes
-* Send the patch to yourself, exactly the way you would, except
- To: and Cc: lines, which would not contain the list and
- maintainer address.
+ (5) Open your Travis CI profile page: https://travis-ci.org/profile
-* Save that patch to a file in UNIX mailbox format. Call it say
- a.patch.
+ (6) Enable Travis CI builds for your Git fork.
-* Try to apply to the tip of the "master" branch from the
- git.git public repository:
+After the initial setup, Travis CI will run whenever you push new changes
+to your fork of Git on GitHub. You can monitor the test state of all your
+branches here: https://travis-ci.org/<Your GitHub handle>/git/branches
- $ git fetch http://kernel.org/pub/scm/git/git.git master:test-apply
- $ git checkout test-apply
- $ git reset --hard
- $ git am a.patch
+If a branch did not pass all test cases then it is marked with a red
+cross. In that case you can click on the failing Travis CI job and
+scroll all the way down in the log. Find the line "<-- Click here to see
+detailed test output!" and click on the triangle next to the log line
+number to expand the detailed test output. Here is such a failing
+example: https://travis-ci.org/git/git/jobs/122676187
-If it does not apply correctly, there can be various reasons.
+Fix the problem and push your fix to your Git fork. This will trigger
+a new Travis CI build to ensure all tests pass.
-* Your patch itself does not apply cleanly. That is _bad_ but
- does not have much to do with your MUA. Please rebase the
- patch appropriately.
-* Your MUA corrupted your patch; "am" would complain that
- the patch does not apply. Look at .git/rebase-apply/ subdirectory and
- see what 'patch' file contains and check for the common
- corruption patterns mentioned above.
+------------------------------------------------
+MUA specific hints
+
+Some of patches I receive or pick up from the list share common
+patterns of breakage. Please make sure your MUA is set up
+properly not to corrupt whitespaces.
-* While you are at it, check what are in 'info' and
- 'final-commit' files as well. If what is in 'final-commit' is
- not exactly what you would want to see in the commit log
- message, it is very likely that your maintainer would end up
- hand editing the log message when he applies your patch.
- Things like "Hi, this is my first patch.\n", if you really
- want to put in the patch e-mail, should come after the
- three-dash line that signals the end of the commit message.
+See the DISCUSSION section of git-format-patch(1) for hints on
+checking your patch by mailing it to yourself and applying with
+git-am(1).
+
+While you are at it, check the resulting commit log message from
+a trial run of applying the patch. If what is in the resulting
+commit is not exactly what you would want to see, it is very
+likely that your maintainer would end up hand editing the log
+message when he applies your patch. Things like "Hi, this is my
+first patch.\n", if you really want to put in the patch e-mail,
+should come after the three-dash line that signals the end of the
+commit message.
Pine
@@ -433,89 +490,10 @@ that or Gentoo did it.) So you need to set the
it.
-Thunderbird
------------
-
-(A Large Angry SCM)
-
-By default, Thunderbird will both wrap emails as well as flag them as
-being 'format=flowed', both of which will make the resulting email unusable
-by git.
-
-Here are some hints on how to successfully submit patches inline using
-Thunderbird.
-
-There are two different approaches. One approach is to configure
-Thunderbird to not mangle patches. The second approach is to use
-an external editor to keep Thunderbird from mangling the patches.
+Thunderbird, KMail, GMail
+-------------------------
-Approach #1 (configuration):
-
-This recipe is current as of Thunderbird 2.0.0.19. Three steps:
- 1. Configure your mail server composition as plain text
- Edit...Account Settings...Composition & Addressing,
- uncheck 'Compose Messages in HTML'.
- 2. Configure your general composition window to not wrap
- Edit..Preferences..Composition, wrap plain text messages at 0
- 3. Disable the use of format=flowed
- Edit..Preferences..Advanced..Config Editor. Search for:
- mailnews.send_plaintext_flowed
- toggle it to make sure it is set to 'false'.
-
-After that is done, you should be able to compose email as you
-otherwise would (cut + paste, git-format-patch | git-imap-send, etc),
-and the patches should not be mangled.
-
-Approach #2 (external editor):
-
-This recipe appears to work with the current [*1*] Thunderbird from Suse.
-
-The following Thunderbird extensions are needed:
- AboutConfig 0.5
- http://aboutconfig.mozdev.org/
- External Editor 0.7.2
- http://globs.org/articles.php?lng=en&pg=8
-
-1) Prepare the patch as a text file using your method of choice.
-
-2) Before opening a compose window, use Edit->Account Settings to
-uncheck the "Compose messages in HTML format" setting in the
-"Composition & Addressing" panel of the account to be used to send the
-patch. [*2*]
-
-3) In the main Thunderbird window, _before_ you open the compose window
-for the patch, use Tools->about:config to set the following to the
-indicated values:
- mailnews.send_plaintext_flowed => false
- mailnews.wraplength => 0
-
-4) Open a compose window and click the external editor icon.
-
-5) In the external editor window, read in the patch file and exit the
-editor normally.
-
-6) Back in the compose window: Add whatever other text you wish to the
-message, complete the addressing and subject fields, and press send.
-
-7) Optionally, undo the about:config/account settings changes made in
-steps 2 & 3.
-
-
-[Footnotes]
-*1* Version 1.0 (20041207) from the MozillaThunderbird-1.0-5 rpm of Suse
-9.3 professional updates.
-
-*2* It may be possible to do this with about:config and the following
-settings but I haven't tried, yet.
- mail.html_compose => false
- mail.identity.default.compose_html => false
- mail.identity.id?.compose_html => false
-
-(Lukas Sandström)
-
-There is a script in contrib/thunderbird-patch-inline which can help
-you include patches with Thunderbird in an easy way. To use it, do the
-steps above and then use the script as the external editor.
+See the MUA-SPECIFIC HINTS section of git-format-patch(1).
Gnus
----
@@ -530,72 +508,3 @@ characters (most notably in people's names), and also
whitespaces (fatal in patches). Running 'C-u g' to display the
message in raw form before using '|' to run the pipe can work
this problem around.
-
-
-KMail
------
-
-This should help you to submit patches inline using KMail.
-
-1) Prepare the patch as a text file.
-
-2) Click on New Mail.
-
-3) Go under "Options" in the Composer window and be sure that
-"Word wrap" is not set.
-
-4) Use Message -> Insert file... and insert the patch.
-
-5) Back in the compose window: add whatever other text you wish to the
-message, complete the addressing and subject fields, and press send.
-
-
-Gmail
------
-
-GMail does not appear to have any way to turn off line wrapping in the web
-interface, so this will mangle any emails that you send. You can however
-use "git send-email" and send your patches through the GMail SMTP server, or
-use any IMAP email client to connect to the google IMAP server and forward
-the emails through that.
-
-To use "git send-email" and send your patches through the GMail SMTP server,
-edit ~/.gitconfig to specify your account settings:
-
-[sendemail]
- smtpencryption = tls
- smtpserver = smtp.gmail.com
- smtpuser = user@gmail.com
- smtppass = p4ssw0rd
- smtpserverport = 587
-
-Once your commits are ready to be sent to the mailing list, run the
-following commands:
-
- $ git format-patch --cover-letter -M origin/master -o outgoing/
- $ edit outgoing/0000-*
- $ git send-email outgoing/*
-
-To submit using the IMAP interface, first, edit your ~/.gitconfig to specify your
-account settings:
-
-[imap]
- folder = "[Gmail]/Drafts"
- host = imaps://imap.gmail.com
- user = user@gmail.com
- pass = p4ssw0rd
- port = 993
- sslverify = false
-
-You might need to instead use: folder = "[Google Mail]/Drafts" if you get an error
-that the "Folder doesn't exist".
-
-Once your commits are ready to be sent to the mailing list, run the
-following commands:
-
- $ git format-patch --cover-letter -M --stdout origin/master | git imap-send
-
-Just make sure to disable line wrapping in the email client (GMail web
-interface will line wrap no matter what, so you need to use a real
-IMAP client).
-