4 Consistent formatting of this file is achieved with:
5 perl ./Porting/podtidy pod/perlgit.pod
9 perlgit - Detailed information about git and the Perl repository
13 This document provides details on using git to develop Perl. If you are
14 just interested in working on a quick patch, see L<perlhack> first.
15 This document is intended for people who are regular contributors to
16 Perl, including those with write access to the git repository.
18 =head1 CLONING THE REPOSITORY
20 All of Perl's source code is kept centrally in a Git repository at
21 I<perl5.git.perl.org>.
23 You can make a read-only clone of the repository by running:
25 % git clone git://perl5.git.perl.org/perl.git perl
27 This uses the git protocol (port 9418).
29 If you cannot use the git protocol for firewall reasons, you can also
30 clone via http, though this is much slower:
32 % git clone http://perl5.git.perl.org/perl.git perl
34 =head1 WORKING WITH THE REPOSITORY
36 Once you have changed into the repository directory, you can inspect
37 it. After a clone the repository will contain a single local branch,
38 which will be the current branch as well, as indicated by the asterisk.
43 Using the -a switch to C<branch> will also show the remote tracking
44 branches in the repository:
52 The branches that begin with "origin" correspond to the "git remote"
53 that you cloned from (which is named "origin"). Each branch on the
54 remote will be exactly tracked by these branches. You should NEVER do
55 work on these remote tracking branches. You only ever do work in a
56 local branch. Local branches can be configured to automerge (on pull)
57 from a designated remote tracking branch. This is the case with the
58 default branch C<blead> which will be configured to merge from the
59 remote tracking branch C<origin/blead>.
61 You can see recent commits:
65 And pull new changes from the repository, and update your local
66 repository (must be clean first)
70 Assuming we are on the branch C<blead> immediately after a pull, this
71 command would be more or less equivalent to:
74 % git merge origin/blead
76 In fact if you want to update your local repository without touching
77 your working directory you do:
81 And if you want to update your remote-tracking branches for all defined
82 remotes simultaneously you can do
86 Neither of these last two commands will update your working directory,
87 however both will update the remote-tracking branches in your
90 To make a local branch of a remote branch:
92 % git checkout -b maint-5.10 origin/maint-5.10
94 To switch back to blead:
98 =head2 Finding out your status
100 The most common git command you will use will probably be
104 This command will produce as output a description of the current state
105 of the repository, including modified files and unignored untracked
106 files, and in addition it will show things like what files have been
107 staged for the next commit, and usually some useful information about
108 how to change things. For instance the following:
112 Your branch is ahead of 'origin/blead' by 1 commit.
114 Changes to be committed:
115 (use "git reset HEAD <file>..." to unstage)
117 modified: pod/perlgit.pod
119 Changes not staged for commit:
120 (use "git add <file>..." to update what will be committed)
121 (use "git checkout -- <file>..." to discard changes in working
124 modified: pod/perlgit.pod
127 (use "git add <file>..." to include in what will be committed)
131 This shows that there were changes to this document staged for commit,
132 and that there were further changes in the working directory not yet
133 staged. It also shows that there was an untracked file in the working
134 directory, and as you can see shows how to change all of this. It also
135 shows that there is one commit on the working branch C<blead> which has
136 not been pushed to the C<origin> remote yet. B<NOTE>: This output
137 is also what you see as a template if you do not provide a message to
140 =head2 Patch workflow
142 First, please read L<perlhack> for details on hacking the Perl core.
143 That document covers many details on how to create a good patch.
145 If you already have a Perl repository, you should ensure that you're on
146 the I<blead> branch, and your repository is up to date:
151 It's preferable to patch against the latest blead version, since this
152 is where new development occurs for all changes other than critical bug
153 fixes. Critical bug fix patches should be made against the relevant
154 maint branches, or should be submitted with a note indicating all the
155 branches where the fix should be applied.
157 Now that we have everything up to date, we need to create a temporary
158 new branch for these changes and switch into it:
160 % git checkout -b orange
162 which is the short form of
165 % git checkout orange
167 Creating a topic branch makes it easier for the maintainers to rebase
168 or merge back into the master blead for a more linear history. If you
169 don't work on a topic branch the maintainer has to manually cherry pick
170 your changes onto blead before they can be applied.
172 That'll get you scolded on perl5-porters, so don't do that. Be Awesome.
174 Then make your changes. For example, if Leon Brocard changes his name
175 to Orange Brocard, we should change his name in the AUTHORS file:
177 % perl -pi -e 's{Leon Brocard}{Orange Brocard}' AUTHORS
179 You can see what files are changed:
183 Changes to be committed:
184 (use "git reset HEAD <file>..." to unstage)
188 And you can see the changes:
191 diff --git a/AUTHORS b/AUTHORS
192 index 293dd70..722c93e 100644
195 @@ -541,7 +541,7 @@ Lars Hecking <lhecking@nmrc.ucc.ie>
196 Laszlo Molnar <laszlo.molnar@eth.ericsson.se>
197 Leif Huhn <leif@hale.dkstat.com>
198 Len Johnson <lenjay@ibm.net>
199 -Leon Brocard <acme@astray.com>
200 +Orange Brocard <acme@astray.com>
201 Les Peters <lpeters@aol.net>
202 Lesley Binks <lesley.binks@gmail.com>
203 Lincoln D. Stein <lstein@cshl.org>
205 Now commit your change locally:
207 % git commit -a -m 'Rename Leon Brocard to Orange Brocard'
208 Created commit 6196c1d: Rename Leon Brocard to Orange Brocard
209 1 files changed, 1 insertions(+), 1 deletions(-)
211 The C<-a> option is used to include all files that git tracks that you
212 have changed. If at this time, you only want to commit some of the
213 files you have worked on, you can omit the C<-a> and use the command
214 C<S<git add I<FILE ...>>> before doing the commit. C<S<git add
215 --interactive>> allows you to even just commit portions of files
216 instead of all the changes in them.
218 The C<-m> option is used to specify the commit message. If you omit it,
219 git will open a text editor for you to compose the message
220 interactively. This is useful when the changes are more complex than
221 the sample given here, and, depending on the editor, to know that the
222 first line of the commit message doesn't exceed the 50 character legal
225 Once you've finished writing your commit message and exited your
226 editor, git will write your change to disk and tell you something like
229 Created commit daf8e63: explain git status and stuff about remotes
230 1 files changed, 83 insertions(+), 3 deletions(-)
232 If you re-run C<git status>, you should see something like this:
237 (use "git add <file>..." to include in what will be committed)
241 nothing added to commit but untracked files present (use "git add" to
244 When in doubt, before you do anything else, check your status and read
245 it carefully, many questions are answered directly by the git status
248 You can examine your last commit with:
252 and if you are not happy with either the description or the patch
253 itself you can fix it up by editing the files once more and then issue:
255 % git commit -a --amend
257 Now you should create a patch file for all your local changes:
259 % git format-patch -M blead..
260 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch
262 Or for a lot of changes, e.g. from a topic branch:
264 % git format-patch --stdout -M blead.. > topic-branch-changes.patch
266 You should now send an email to
267 L<perlbug@perl.org|mailto:perlbug@perl.org> with a description of your
268 changes, and include this patch file as an attachment. In addition to
269 being tracked by RT, mail to perlbug will automatically be forwarded to
270 perl5-porters (with manual moderation, so please be patient). You
271 should only send patches to
272 L<perl5-porters@perl.org|mailto:perl5-porters@perl.org> directly if the
273 patch is not ready to be applied, but intended for discussion.
275 Please do not use git-send-email(1) to send your patch. See L<Sending
276 patch emails|/Sending patch emails> for more information.
278 If you want to delete your temporary branch, you may do so with:
281 % git branch -d orange
282 error: The branch 'orange' is not an ancestor of your current HEAD.
283 If you are sure you want to delete it, run 'git branch -D orange'.
284 % git branch -D orange
285 Deleted branch orange.
287 =head2 Committing your changes
289 Assuming that you'd like to commit all the changes you've made as a
290 single atomic unit, run this command:
294 (That C<-a> tells git to add every file you've changed to this commit.
295 New files aren't automatically added to your commit when you use
296 C<commit -a> If you want to add files or to commit some, but not all of
297 your changes, have a look at the documentation for C<git add>.)
299 Git will start up your favorite text editor, so that you can craft a
300 commit message for your change. See L<perlhack/Commit message> for more
301 information about what makes a good commit message.
303 Once you've finished writing your commit message and exited your
304 editor, git will write your change to disk and tell you something like
307 Created commit daf8e63: explain git status and stuff about remotes
308 1 files changed, 83 insertions(+), 3 deletions(-)
310 If you re-run C<git status>, you should see something like this:
314 Your branch is ahead of 'origin/blead' by 2 commits.
315 (use "git push" to publish your local commits)
317 (use "git add <file>..." to include in what will be committed)
321 nothing added to commit but untracked files present (use "git add" to
324 When in doubt, before you do anything else, check your status and read
325 it carefully, many questions are answered directly by the git status
328 =head2 Sending patch emails
330 After you've generated your patch you should send it
331 to L<perlbug@perl.org|mailto:perlbug@perl.org> (as discussed L<in the
332 previous section|/"Patch workflow">) with a normal mail client as an
333 attachment, along with a description of the patch.
335 You B<must not> use git-send-email(1) to send patches generated with
336 git-format-patch(1). The RT ticketing system living behind
337 L<perlbug@perl.org|mailto:perlbug@perl.org> does not respect the inline
338 contents of E-Mails, sending an inline patch to RT guarantees that your
339 patch will be destroyed.
341 Someone may download your patch from RT, which will result in the
342 subject (the first line of the commit message) being omitted. See
343 L<RT #74192|https://rt.perl.org/Ticket/Display.html?id=74192> and
344 L<commit a4583001|http://perl5.git.perl.org/perl.git/commitdiff/a4583001>
345 for an example. Alternatively someone may
346 apply your patch from RT after it arrived in their mailbox, by which
347 time RT will have modified the inline content of the message. See
348 L<RT #74532|https://rt.perl.org/Ticket/Display.html?id=74532> and
349 L<commit f9bcfeac|http://perl5.git.perl.org/perl.git/commitdiff/f9bcfeac>
350 for a bad example of this failure mode.
352 =head2 A note on derived files
354 Be aware that many files in the distribution are derivative--avoid
355 patching them, because git won't see the changes to them, and the build
356 process will overwrite them. Patch the originals instead. Most
357 utilities (like perldoc) are in this category, i.e. patch
358 F<utils/perldoc.PL> rather than F<utils/perldoc>. Similarly, don't
359 create patches for files under F<$src_root/ext> from their copies found
360 in F<$install_root/lib>. If you are unsure about the proper location of
361 a file that may have gotten copied while building the source
362 distribution, consult the F<MANIFEST>.
364 =head2 Cleaning a working directory
366 The command C<git clean> can with varying arguments be used as a
367 replacement for C<make clean>.
369 To reset your working directory to a pristine condition you can do:
373 However, be aware this will delete ALL untracked content. You can use
377 to remove all ignored untracked files, such as build and test
378 byproduct, but leave any manually created files alone.
380 If you only want to cancel some uncommitted edits, you can use C<git
381 checkout> and give it a list of files to be reverted, or C<git checkout
382 -f> to revert them all.
384 If you want to cancel one or several commits, you can use C<git reset>.
388 C<git> provides a built-in way to determine which commit should be blamed
389 for introducing a given bug. C<git bisect> performs a binary search of
390 history to locate the first failing commit. It is fast, powerful and
391 flexible, but requires some setup and to automate the process an auxiliary
392 shell script is needed.
394 The core provides a wrapper program, F<Porting/bisect.pl>, which attempts to
395 simplify as much as possible, making bisecting as simple as running a Perl
396 one-liner. For example, if you want to know when this became an error:
402 .../Porting/bisect.pl -e 'my $a := 2;'
404 Using F<Porting/bisect.pl>, with one command (and no other files) it's easy to
411 Which commit caused this example code to break?
415 Which commit caused this example code to start working?
419 Which commit added the first file to match this regex?
423 Which commit removed the last file to match this regex?
427 usually without needing to know which versions of perl to use as start and
428 end revisions, as F<Porting/bisect.pl> automatically searches to find the
429 earliest stable version for which the test case passes. Run
430 C<Porting/bisect.pl --help> for the full documentation, including how to
431 set the C<Configure> and build time options.
433 If you require more flexibility than F<Porting/bisect.pl> has to offer, you'll
434 need to run C<git bisect> yourself. It's most useful to use C<git bisect run>
435 to automate the building and testing of perl revisions. For this you'll need
436 a shell script for C<git> to call to test a particular revision. An example
437 script is F<Porting/bisect-example.sh>, which you should copy B<outside> of
438 the repository, as the bisect process will reset the state to a clean checkout
439 as it runs. The instructions below assume that you copied it as F<~/run> and
440 then edited it as appropriate.
442 You first enter in bisect mode with:
446 For example, if the bug is present on C<HEAD> but wasn't in 5.10.0,
447 C<git> will learn about this when you enter:
450 % git bisect good perl-5.10.0
451 Bisecting: 853 revisions left to test after this
453 This results in checking out the median commit between C<HEAD> and
454 C<perl-5.10.0>. You can then run the bisecting process with:
456 % git bisect run ~/run
458 When the first bad commit is isolated, C<git bisect> will tell you so:
460 ca4cfd28534303b82a216cfe83a1c80cbc3b9dc5 is first bad commit
461 commit ca4cfd28534303b82a216cfe83a1c80cbc3b9dc5
462 Author: Dave Mitchell <davem@fdisolutions.com>
463 Date: Sat Feb 9 14:56:23 2008 +0000
465 [perl #49472] Attributes + Unknown Error
470 You can peek into the bisecting process with C<git bisect log> and
471 C<git bisect visualize>. C<git bisect reset> will get you out of bisect
474 Please note that the first C<good> state must be an ancestor of the
475 first C<bad> state. If you want to search for the commit that I<solved>
476 some bug, you have to negate your test case (i.e. exit with C<1> if OK
477 and C<0> if not) and still mark the lower bound as C<good> and the
478 upper as C<bad>. The "first bad commit" has then to be understood as
479 the "first commit where the bug is solved".
481 C<git help bisect> has much more information on how you can tweak your
484 Following bisection you may wish to configure, build and test perl at
485 commits identified by the bisection process. Sometimes, particularly
486 with older perls, C<make> may fail during this process. In this case
487 you may be able to patch the source code at the older commit point. To
488 do so, please follow the suggestions provided in
489 L<perlhack/Building perl at older commits>.
491 =head2 Topic branches and rewriting history
493 Individual committers should create topic branches under
494 B<yourname>/B<some_descriptive_name>:
496 % branch="$yourname/$some_descriptive_name"
497 % git checkout -b $branch
498 ... do local edits, commits etc ...
499 % git push origin -u $branch
501 Should you be stuck with an ancient version of git (prior to 1.7), then
502 C<git push> will not have the C<-u> switch, and you have to replace the
503 last step with the following sequence:
505 % git push origin $branch:refs/heads/$branch
506 % git config branch.$branch.remote origin
507 % git config branch.$branch.merge refs/heads/$branch
509 If you want to make changes to someone else's topic branch, you should
510 check with its creator before making any change to it.
513 might sometimes find that the original author has edited the branch's
514 history. There are lots of good reasons for this. Sometimes, an author
515 might simply be rebasing the branch onto a newer source point.
516 Sometimes, an author might have found an error in an early commit which
517 they wanted to fix before merging the branch to blead.
519 Currently the master repository is configured to forbid
520 non-fast-forward merges. This means that the branches within can not be
521 rebased and pushed as a single step.
523 The only way you will ever be allowed to rebase or modify the history
524 of a pushed branch is to delete it and push it as a new branch under
525 the same name. Please think carefully about doing this. It may be
526 better to sequentially rename your branches so that it is easier for
527 others working with you to cherry-pick their local changes onto the new
528 version. (XXX: needs explanation).
530 If you want to rebase a personal topic branch, you will have to delete
531 your existing topic branch and push as a new version of it. You can do
532 this via the following formula (see the explanation about C<refspec>'s
533 in the git push documentation for details) after you have rebased your
537 % git checkout $user/$topic
539 % git rebase origin/blead
541 # then "delete-and-push"
542 % git push origin :$user/$topic
543 % git push origin $user/$topic
545 B<NOTE:> it is forbidden at the repository level to delete any of the
546 "primary" branches. That is any branch matching
547 C<m!^(blead|maint|perl)!>. Any attempt to do so will result in git
548 producing an error like this:
550 % git push origin :blead
551 *** It is forbidden to delete blead/maint branches in this repository
552 error: hooks/update exited with error code 1
553 error: hook declined to update refs/heads/blead
554 To ssh://perl5.git.perl.org/perl
555 ! [remote rejected] blead (hook declined)
556 error: failed to push some refs to 'ssh://perl5.git.perl.org/perl'
558 As a matter of policy we do B<not> edit the history of the blead and
559 maint-* branches. If a typo (or worse) sneaks into a commit to blead or
560 maint-*, we'll fix it in another commit. The only types of updates
561 allowed on these branches are "fast-forwards", where all history is
564 Annotated tags in the canonical perl.git repository will never be
565 deleted or modified. Think long and hard about whether you want to push
566 a local tag to perl.git before doing so. (Pushing simple tags is
571 The perl history contains one mistake which was not caught in the
572 conversion: a merge was recorded in the history between blead and
573 maint-5.10 where no merge actually occurred. Due to the nature of git,
574 this is now impossible to fix in the public repository. You can remove
575 this mis-merge locally by adding the following line to your
576 C<.git/info/grafts> file:
578 296f12bbbbaa06de9be9d09d3dcf8f4528898a49 434946e0cb7a32589ed92d18008aaa1d88515930
580 It is particularly important to have this graft line if any bisecting
581 is done in the area of the "merge" in question.
583 =head1 WRITE ACCESS TO THE GIT REPOSITORY
585 Once you have write access, you will need to modify the URL for the
586 origin remote to enable pushing. Edit F<.git/config> with the
587 git-config(1) command:
589 % git config remote.origin.url ssh://perl5.git.perl.org/perl.git
591 You can also set up your user name and e-mail address. Most people do
592 this once globally in their F<~/.gitconfig> by doing something like:
594 % git config --global user.name "Ævar Arnfjörð Bjarmason"
595 % git config --global user.email avarab@gmail.com
597 However, if you'd like to override that just for perl,
598 execute something like the following in F<perl>:
600 % git config user.email avar@cpan.org
602 It is also possible to keep C<origin> as a git remote, and add a new
603 remote for ssh access:
605 % git remote add camel perl5.git.perl.org:/perl.git
607 This allows you to update your local repository by pulling from
608 C<origin>, which is faster and doesn't require you to authenticate, and
609 to push your changes back with the C<camel> remote:
614 The C<fetch> command just updates the C<camel> refs, as the objects
615 themselves should have been fetched when pulling from C<origin>.
617 =head2 Accepting a patch
619 If you have received a patch file generated using the above section,
620 you should try out the patch.
622 First we need to create a temporary new branch for these changes and
625 % git checkout -b experimental
627 Patches that were formatted by C<git format-patch> are applied with
630 % git am 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch
631 Applying Rename Leon Brocard to Orange Brocard
633 Note that some UNIX mail systems can mess with text attachments containing
634 'From '. This will fix them up:
636 % perl -pi -e's/^>From /From /' \
637 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch
639 If just a raw diff is provided, it is also possible use this two-step
642 % git apply bugfix.diff
643 % git commit -a -m "Some fixing" \
644 --author="That Guy <that.guy@internets.com>"
646 Now we can inspect the change:
649 commit b1b3dab48344cff6de4087efca3dbd63548ab5e2
650 Author: Leon Brocard <acme@astray.com>
651 Date: Fri Dec 19 17:02:59 2008 +0000
653 Rename Leon Brocard to Orange Brocard
655 diff --git a/AUTHORS b/AUTHORS
656 index 293dd70..722c93e 100644
659 @@ -541,7 +541,7 @@ Lars Hecking <lhecking@nmrc.ucc.ie>
660 Laszlo Molnar <laszlo.molnar@eth.ericsson.se>
661 Leif Huhn <leif@hale.dkstat.com>
662 Len Johnson <lenjay@ibm.net>
663 -Leon Brocard <acme@astray.com>
664 +Orange Brocard <acme@astray.com>
665 Les Peters <lpeters@aol.net>
666 Lesley Binks <lesley.binks@gmail.com>
667 Lincoln D. Stein <lstein@cshl.org>
669 If you are a committer to Perl and you think the patch is good, you can
670 then merge it into blead then push it out to the main repository:
673 % git merge experimental
674 % git push origin blead
676 If you want to delete your temporary branch, you may do so with:
679 % git branch -d experimental
680 error: The branch 'experimental' is not an ancestor of your current
681 HEAD. If you are sure you want to delete it, run 'git branch -D
683 % git branch -D experimental
684 Deleted branch experimental.
686 =head2 Committing to blead
688 The 'blead' branch will become the next production release of Perl.
690 Before pushing I<any> local change to blead, it's incredibly important
691 that you do a few things, lest other committers come after you with
692 pitchforks and torches:
698 Make sure you have a good commit message. See L<perlhack/Commit
699 message> for details.
703 Run the test suite. You might not think that one typo fix would break a
704 test file. You'd be wrong. Here's an example of where not running the
705 suite caused problems. A patch was submitted that added a couple of
706 tests to an existing F<.t>. It couldn't possibly affect anything else, so
707 no need to test beyond the single affected F<.t>, right? But, the
708 submitter's email address had changed since the last of their
709 submissions, and this caused other tests to fail. Running the test
710 target given in the next item would have caught this problem.
714 If you don't run the full test suite, at least C<make test_porting>.
715 This will run basic sanity checks. To see which sanity checks, have a
716 look in F<t/porting>.
720 If you make any changes that affect miniperl or core routines that have
721 different code paths for miniperl, be sure to run C<make minitest>.
722 This will catch problems that even the full test suite will not catch
723 because it runs a subset of tests under miniperl rather than perl.
727 =head2 On merging and rebasing
729 Simple, one-off commits pushed to the 'blead' branch should be simple
730 commits that apply cleanly. In other words, you should make sure your
731 work is committed against the current position of blead, so that you can
732 push back to the master repository without merging.
734 Sometimes, blead will move while you're building or testing your
735 changes. When this happens, your push will be rejected with a message
738 To ssh://perl5.git.perl.org/perl.git
739 ! [rejected] blead -> blead (non-fast-forward)
740 error: failed to push some refs to 'ssh://perl5.git.perl.org/perl.git'
741 To prevent you from losing history, non-fast-forward updates were
742 rejected Merge the remote changes (e.g. 'git pull') before pushing
743 again. See the 'Note about fast-forwards' section of 'git push --help'
746 When this happens, you can just I<rebase> your work against the new
747 position of blead, like this (assuming your remote for the master
748 repository is "p5p"):
751 % git rebase p5p/blead
753 You will see your commits being re-applied, and you will then be able to
754 push safely. More information about rebasing can be found in the
755 documentation for the git-rebase(1) command.
757 For larger sets of commits that only make sense together, or that would
758 benefit from a summary of the set's purpose, you should use a merge
759 commit. You should perform your work on a L<topic branch|/Topic
760 branches and rewriting history>, which you should regularly rebase
761 against blead to ensure that your code is not broken by blead moving.
762 When you have finished your work, please perform a final rebase and
763 test. Linear history is something that gets lost with every
764 commit on blead, but a final rebase makes the history linear
765 again, making it easier for future maintainers to see what has
766 happened. Rebase as follows (assuming your work was on the
767 branch C<< committer/somework >>):
769 % git checkout committer/somework
772 Then you can merge it into master like this:
775 % git merge --no-ff --no-commit committer/somework
778 The switches above deserve explanation. C<--no-ff> indicates that even
779 if all your work can be applied linearly against blead, a merge commit
780 should still be prepared. This ensures that all your work will be shown
781 as a side branch, with all its commits merged into the mainstream blead
784 C<--no-commit> means that the merge commit will be I<prepared> but not
785 I<committed>. The commit is then actually performed when you run the
786 next command, which will bring up your editor to describe the commit.
787 Without C<--no-commit>, the commit would be made with nearly no useful
788 message, which would greatly diminish the value of the merge commit as a
789 placeholder for the work's description.
791 When describing the merge commit, explain the purpose of the branch, and
792 keep in mind that this description will probably be used by the
793 eventual release engineer when reviewing the next perldelta document.
795 =head2 Committing to maintenance versions
797 Maintenance versions should only be altered to add critical bug fixes,
800 To commit to a maintenance version of perl, you need to create a local
803 % git checkout --track -b maint-5.005 origin/maint-5.005
805 This creates a local branch named C<maint-5.005>, which tracks the
806 remote branch C<origin/maint-5.005>. Then you can pull, commit, merge
809 You can also cherry-pick commits from blead and another branch, by
810 using the C<git cherry-pick> command. It is recommended to use the
811 B<-x> option to C<git cherry-pick> in order to record the SHA1 of the
812 original commit in the new commit message.
814 Before pushing any change to a maint version, make sure you've
815 satisfied the steps in L</Committing to blead> above.
817 =head2 Merging from a branch via GitHub
819 While we don't encourage the submission of patches via GitHub, that
820 will still happen. Here is a guide to merging patches from a GitHub
823 % git remote add avar git://github.com/avar/perl.git
826 Now you can see the differences between the branch and blead:
828 % git diff avar/orange
830 And you can see the commits:
832 % git log avar/orange
834 If you approve of a specific commit, you can cherry pick it:
836 % git cherry-pick 0c24b290ae02b2ab3304f51d5e11e85eb3659eae
838 Or you could just merge the whole branch if you like it all:
840 % git merge avar/orange
842 And then push back to the repository:
844 % git push origin blead
846 =head2 Using a smoke-me branch to test changes
848 Sometimes a change affects code paths which you cannot test on the OSes
849 which are directly available to you and it would be wise to have users
850 on other OSes test the change before you commit it to blead.
852 Fortunately, there is a way to get your change smoke-tested on various
853 OSes: push it to a "smoke-me" branch and wait for certain automated
854 smoke-testers to report the results from their OSes.
855 A "smoke-me" branch is identified by the branch name: specifically, as
856 seen on perl5.git.perl.org it must be a local branch whose first name
857 component is precisely C<smoke-me>.
859 The procedure for doing this is roughly as follows (using the example of
860 of tonyc's smoke-me branch called win32stat):
862 First, make a local branch and switch to it:
864 % git checkout -b win32stat
866 Make some changes, build perl and test your changes, then commit them to
867 your local branch. Then push your local branch to a remote smoke-me
870 % git push origin win32stat:smoke-me/tonyc/win32stat
872 Now you can switch back to blead locally:
876 and continue working on other things while you wait a day or two,
877 keeping an eye on the results reported for your smoke-me branch at
878 L<http://perl.develop-help.com/?b=smoke-me/tonyc/win32state>.
880 If all is well then update your blead branch:
884 then checkout your smoke-me branch once more and rebase it on blead:
886 % git rebase blead win32stat
888 Now switch back to blead and merge your smoke-me branch into it:
891 % git merge win32stat
893 As described earlier, if there are many changes on your smoke-me branch
894 then you should prepare a merge commit in which to give an overview of
895 those changes by using the following command instead of the last
898 % git merge win32stat --no-ff --no-commit
900 You should now build perl and test your (merged) changes one last time
901 (ideally run the whole test suite, but failing that at least run the
902 F<t/porting/*.t> tests) before pushing your changes as usual:
904 % git push origin blead
906 Finally, you should then delete the remote smoke-me branch:
908 % git push origin :smoke-me/tonyc/win32stat
910 (which is likely to produce a warning like this, which can be ignored:
912 remote: fatal: ambiguous argument
913 'refs/heads/smoke-me/tonyc/win32stat':
914 unknown revision or path not in the working tree.
915 remote: Use '--' to separate paths from revisions
917 ) and then delete your local branch:
919 % git branch -d win32stat
921 =head2 A note on camel and dromedary
923 The committers have SSH access to the two servers that serve
924 C<perl5.git.perl.org>. One is C<perl5.git.perl.org> itself (I<camel>),
925 which is the 'master' repository. The second one is
926 C<users.perl5.git.perl.org> (I<dromedary>), which can be used for
927 general testing and development. Dromedary syncs the git tree from
928 camel every few minutes, you should not push there. Both machines also
929 have a full CPAN mirror in F</srv/CPAN>, please use this. To share files
930 with the general public, dromedary serves your F<~/public_html/> as
931 C<L<http://users.perl5.git.perl.org/~yourlogin/>>
933 These hosts have fairly strict firewalls to the outside. Outgoing, only
934 rsync, ssh and git are allowed. For http and ftp, you can use
935 L<http://webproxy:3128> as proxy. Incoming, the firewall tries to detect
936 attacks and blocks IP addresses with suspicious activity. This
937 sometimes (but very rarely) has false positives and you might get
938 blocked. The quickest way to get unblocked is to notify the admins.
940 These two boxes are owned, hosted, and operated by booking.com. You can
941 reach the sysadmins in #p5p on irc.perl.org or via mail to
942 L<perl5-porters@perl.org|mailto:perl5-porters@perl.org>.