This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
pod/perldelta.pod: copied from Porting/perldelta_template.pod
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1=encoding utf8
2
3=for comment
4Consistent formatting of this file is achieved with:
5 perl ./Porting/podtidy pod/perlgit.pod
6
7=head1 NAME
8
9perlgit - Detailed information about git and the Perl repository
10
11=head1 DESCRIPTION
12
13This document provides details on using git to develop Perl. If you are
14just interested in working on a quick patch, see L<perlhack> first.
15This document is intended for people who are regular contributors to
16Perl, including those with write access to the git repository.
17
18=head1 CLONING THE REPOSITORY
19
20All of Perl's source code is kept centrally in a Git repository at
21I<perl5.git.perl.org>.
22
23You can make a read-only clone of the repository by running:
24
25 % git clone git://perl5.git.perl.org/perl.git perl
26
27This uses the git protocol (port 9418).
28
29If you cannot use the git protocol for firewall reasons, you can also
30clone via http, though this is much slower:
31
32 % git clone http://perl5.git.perl.org/perl.git perl
33
34=head1 WORKING WITH THE REPOSITORY
35
36Once you have changed into the repository directory, you can inspect
37it. After a clone the repository will contain a single local branch,
38which will be the current branch as well, as indicated by the asterisk.
39
40 % git branch
41 * blead
42
43Using the -a switch to C<branch> will also show the remote tracking
44branches in the repository:
45
46 % git branch -a
47 * blead
48 origin/HEAD
49 origin/blead
50 ...
51
52The branches that begin with "origin" correspond to the "git remote"
53that you cloned from (which is named "origin"). Each branch on the
54remote will be exactly tracked by theses branches. You should NEVER do
55work on these remote tracking branches. You only ever do work in a
56local branch. Local branches can be configured to automerge (on pull)
57from a designated remote tracking branch. This is the case with the
58default branch C<blead> which will be configured to merge from the
59remote tracking branch C<origin/blead>.
60
61You can see recent commits:
62
63 % git log
64
65And pull new changes from the repository, and update your local
66repository (must be clean first)
67
68 % git pull
69
70Assuming we are on the branch C<blead> immediately after a pull, this
71command would be more or less equivalent to:
72
73 % git fetch
74 % git merge origin/blead
75
76In fact if you want to update your local repository without touching
77your working directory you do:
78
79 % git fetch
80
81And if you want to update your remote-tracking branches for all defined
82remotes simultaneously you can do
83
84 % git remote update
85
86Neither of these last two commands will update your working directory,
87however both will update the remote-tracking branches in your
88repository.
89
90To make a local branch of a remote branch:
91
92 % git checkout -b maint-5.10 origin/maint-5.10
93
94To switch back to blead:
95
96 % git checkout blead
97
98=head2 Finding out your status
99
100The most common git command you will use will probably be
101
102 % git status
103
104This command will produce as output a description of the current state
105of the repository, including modified files and unignored untracked
106files, and in addition it will show things like what files have been
107staged for the next commit, and usually some useful information about
108how to change things. For instance the following:
109
110 $ git status
111 # On branch blead
112 # Your branch is ahead of 'origin/blead' by 1 commit.
113 #
114 # Changes to be committed:
115 # (use "git reset HEAD <file>..." to unstage)
116 #
117 # modified: pod/perlgit.pod
118 #
119 # Changed but not updated:
120 # (use "git add <file>..." to update what will be committed)
121 #
122 # modified: pod/perlgit.pod
123 #
124 # Untracked files:
125 # (use "git add <file>..." to include in what will be committed)
126 #
127 # deliberate.untracked
128
129This shows that there were changes to this document staged for commit,
130and that there were further changes in the working directory not yet
131staged. It also shows that there was an untracked file in the working
132directory, and as you can see shows how to change all of this. It also
133shows that there is one commit on the working branch C<blead> which has
134not been pushed to the C<origin> remote yet. B<NOTE>: that this output
135is also what you see as a template if you do not provide a message to
136C<git commit>.
137
138=head2 Patch workflow
139
140First, please read L<perlhack> for details on hacking the Perl core.
141That document covers many details on how to create a good patch.
142
143If you already have a Perl repository, you should ensure that you're on
144the I<blead> branch, and your repository is up to date:
145
146 % git checkout blead
147 % git pull
148
149It's preferable to patch against the latest blead version, since this
150is where new development occurs for all changes other than critical bug
151fixes. Critical bug fix patches should be made against the relevant
152maint branches, or should be submitted with a note indicating all the
153branches where the fix should be applied.
154
155Now that we have everything up to date, we need to create a temporary
156new branch for these changes and switch into it:
157
158 % git checkout -b orange
159
160which is the short form of
161
162 % git branch orange
163 % git checkout orange
164
165Creating a topic branch makes it easier for the maintainers to rebase
166or merge back into the master blead for a more linear history. If you
167don't work on a topic branch the maintainer has to manually cherry pick
168your changes onto blead before they can be applied.
169
170That'll get you scolded on perl5-porters, so don't do that. Be Awesome.
171
172Then make your changes. For example, if Leon Brocard changes his name
173to Orange Brocard, we should change his name in the AUTHORS file:
174
175 % perl -pi -e 's{Leon Brocard}{Orange Brocard}' AUTHORS
176
177You can see what files are changed:
178
179 % git status
180 # On branch orange
181 # Changes to be committed:
182 # (use "git reset HEAD <file>..." to unstage)
183 #
184 # modified: AUTHORS
185 #
186
187And you can see the changes:
188
189 % git diff
190 diff --git a/AUTHORS b/AUTHORS
191 index 293dd70..722c93e 100644
192 --- a/AUTHORS
193 +++ b/AUTHORS
194 @@ -541,7 +541,7 @@ Lars Hecking <lhecking@nmrc.ucc.ie>
195 Laszlo Molnar <laszlo.molnar@eth.ericsson.se>
196 Leif Huhn <leif@hale.dkstat.com>
197 Len Johnson <lenjay@ibm.net>
198 -Leon Brocard <acme@astray.com>
199 +Orange Brocard <acme@astray.com>
200 Les Peters <lpeters@aol.net>
201 Lesley Binks <lesley.binks@gmail.com>
202 Lincoln D. Stein <lstein@cshl.org>
203
204Now commit your change locally:
205
206 % git commit -a -m 'Rename Leon Brocard to Orange Brocard'
207 Created commit 6196c1d: Rename Leon Brocard to Orange Brocard
208 1 files changed, 1 insertions(+), 1 deletions(-)
209
210The C<-a> option is used to include all files that git tracks that you
211have changed. If at this time, you only want to commit some of the
212files you have worked on, you can omit the C<-a> and use the command
213C<S<git add I<FILE ...>>> before doing the commit. C<S<git add
214--interactive>> allows you to even just commit portions of files
215instead of all the changes in them.
216
217The C<-m> option is used to specify the commit message. If you omit it,
218git will open a text editor for you to compose the message
219interactively. This is useful when the changes are more complex than
220the sample given here, and, depending on the editor, to know that the
221first line of the commit message doesn't exceed the 50 character legal
222maximum.
223
224Once you've finished writing your commit message and exited your
225editor, git will write your change to disk and tell you something like
226this:
227
228 Created commit daf8e63: explain git status and stuff about remotes
229 1 files changed, 83 insertions(+), 3 deletions(-)
230
231If you re-run C<git status>, you should see something like this:
232
233 % git status
234 # On branch blead
235 # Your branch is ahead of 'origin/blead' by 2 commits.
236 #
237 # Untracked files:
238 # (use "git add <file>..." to include in what will be committed)
239 #
240 # deliberate.untracked
241 nothing added to commit but untracked files present (use "git add" to track)
242
243When in doubt, before you do anything else, check your status and read
244it carefully, many questions are answered directly by the git status
245output.
246
247You can examine your last commit with:
248
249 % git show HEAD
250
251and if you are not happy with either the description or the patch
252itself you can fix it up by editing the files once more and then issue:
253
254 % git commit -a --amend
255
256Now you should create a patch file for all your local changes:
257
258 % git format-patch -M origin..
259 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch
260
261You should now send an email to to
262L<perlbug@perl.org|mailto:perlbug@perl.org> with a description of your
263changes, and include this patch file as an attachment. In addition to
264being tracked by RT, mail to perlbug will automatically be forwarded to
265perl5-porters (with manual moderation, so please be patient). You
266should only send patches to
267L<perl5-porters@perl.org|mailto:perl5-porters@perl.org> directly if the
268patch is not ready to be applied, but intended for discussion.
269
270See the next section for how to configure and use git to send these
271emails for you.
272
273If you want to delete your temporary branch, you may do so with:
274
275 % git checkout blead
276 % git branch -d orange
277 error: The branch 'orange' is not an ancestor of your current HEAD.
278 If you are sure you want to delete it, run 'git branch -D orange'.
279 % git branch -D orange
280 Deleted branch orange.
281
282=head2 Committing your changes
283
284Assuming that you'd like to commit all the changes you've made as a
285single atomic unit, run this command:
286
287 % git commit -a
288
289(That C<-a> tells git to add every file you've changed to this commit.
290New files aren't automatically added to your commit when you use
291C<commit -a> If you want to add files or to commit some, but not all of
292your changes, have a look at the documentation for C<git add>.)
293
294Git will start up your favorite text editor, so that you can craft a
295commit message for your change. See L<perlhack/Commit message> for more
296information about what makes a good commit message.
297
298Once you've finished writing your commit message and exited your
299editor, git will write your change to disk and tell you something like
300this:
301
302 Created commit daf8e63: explain git status and stuff about remotes
303 1 files changed, 83 insertions(+), 3 deletions(-)
304
305If you re-run C<git status>, you should see something like this:
306
307 % git status
308 # On branch blead
309 # Your branch is ahead of 'origin/blead' by 2 commits.
310 #
311 # Untracked files:
312 # (use "git add <file>..." to include in what will be committed)
313 #
314 # deliberate.untracked
315 nothing added to commit but untracked files present (use "git add" to track)
316
317When in doubt, before you do anything else, check your status and read
318it carefully, many questions are answered directly by the git status
319output.
320
321=head2 Using git to send patch emails
322
323Please read L<perlhack> first in order to figure out where your patches
324should be sent.
325
326In your ~/git/perl repository, set the destination email to perl's bug
327tracker:
328
329 $ git config sendemail.to perlbug@perl.org
330
331Or maybe perl5-porters:
332
333 $ git config sendemail.to perl5-porters@perl.org
334
335Then you can use git directly to send your patch emails:
336
337 $ git send-email 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch
338
339You may need to set some configuration variables for your particular
340email service provider. For example, to set your global git config to
341send email via a gmail account:
342
343 $ git config --global sendemail.smtpserver smtp.gmail.com
344 $ git config --global sendemail.smtpssl 1
345 $ git config --global sendemail.smtpuser YOURUSERNAME@gmail.com
346
347With this configuration, you will be prompted for your gmail password
348when you run 'git send-email'. You can also configure
349C<sendemail.smtppass> with your password if you don't care about having
350your password in the .gitconfig file.
351
352=head2 A note on derived files
353
354Be aware that many files in the distribution are derivative--avoid
355patching them, because git won't see the changes to them, and the build
356process will overwrite them. Patch the originals instead. Most
357utilities (like perldoc) are in this category, i.e. patch
358F<utils/perldoc.PL> rather than F<utils/perldoc>. Similarly, don't
359create patches for files under $src_root/ext from their copies found in
360$install_root/lib. If you are unsure about the proper location of a
361file that may have gotten copied while building the source
362distribution, consult the C<MANIFEST>.
363
364=head2 Cleaning a working directory
365
366The command C<git clean> can with varying arguments be used as a
367replacement for C<make clean>.
368
369To reset your working directory to a pristine condition you can do:
370
371 % git clean -dxf
372
373However, be aware this will delete ALL untracked content. You can use
374
375 % git clean -Xf
376
377to remove all ignored untracked files, such as build and test
378byproduct, but leave any manually created files alone.
379
380If you only want to cancel some uncommitted edits, you can use C<git
381checkout> and give it a list of files to be reverted, or C<git checkout
382-f> to revert them all.
383
384If you want to cancel one or several commits, you can use C<git reset>.
385
386=head2 Bisecting
387
388C<git> provides a built-in way to determine, with a binary search in
389the history, which commit should be blamed for introducing a given bug.
390
391Suppose that we have a script F<~/testcase.pl> that exits with C<0>
392when some behaviour is correct, and with C<1> when it's faulty. You
393need an helper script that automates building C<perl> and running the
394testcase:
395
396 % cat ~/run
397 #!/bin/sh
398 git clean -dxf
399
400 # If you get './makedepend: 1: Syntax error: Unterminated quoted
401 # string' when bisecting versions of perl older than 5.9.5 this hack
402 # will work around the bug in makedepend.SH which was fixed in
403 # version 96a8704c. Make sure to comment out `git checkout makedepend.SH'
404 # below too.
405 git show blead:makedepend.SH > makedepend.SH
406
407 # If you can use ccache, add -Dcc=ccache\ gcc -Dld=gcc to the Configure line
408 # if Encode is not needed for the test, you can speed up the bisect by
409 # excluding it from the runs with -Dnoextensions=Encode
410 sh Configure -des -Dusedevel -Doptimize="-g"
411 test -f config.sh || exit 125
412 # Correct makefile for newer GNU gcc
413 perl -ni -we 'print unless /<(?:built-in|command)/' makefile x2p/makefile
414 # if you just need miniperl, replace test_prep with miniperl
415 make test_prep
416 [ -x ./perl ] || exit 125
417 ./perl -Ilib ~/testcase.pl
418 ret=$?
419 [ $ret -gt 127 ] && ret=127
420 # git checkout makedepend.SH
421 git clean -dxf
422 exit $ret
423
424This script may return C<125> to indicate that the corresponding commit
425should be skipped. Otherwise, it returns the status of
426F<~/testcase.pl>.
427
428You first enter in bisect mode with:
429
430 % git bisect start
431
432For example, if the bug is present on C<HEAD> but wasn't in 5.10.0,
433C<git> will learn about this when you enter:
434
435 % git bisect bad
436 % git bisect good perl-5.10.0
437 Bisecting: 853 revisions left to test after this
438
439This results in checking out the median commit between C<HEAD> and
440C<perl-5.10.0>. You can then run the bisecting process with:
441
442 % git bisect run ~/run
443
444When the first bad commit is isolated, C<git bisect> will tell you so:
445
446 ca4cfd28534303b82a216cfe83a1c80cbc3b9dc5 is first bad commit
447 commit ca4cfd28534303b82a216cfe83a1c80cbc3b9dc5
448 Author: Dave Mitchell <davem@fdisolutions.com>
449 Date: Sat Feb 9 14:56:23 2008 +0000
450
451 [perl #49472] Attributes + Unknown Error
452 ...
453
454 bisect run success
455
456You can peek into the bisecting process with C<git bisect log> and
457C<git bisect visualize>. C<git bisect reset> will get you out of bisect
458mode.
459
460Please note that the first C<good> state must be an ancestor of the
461first C<bad> state. If you want to search for the commit that I<solved>
462some bug, you have to negate your test case (i.e. exit with C<1> if OK
463and C<0> if not) and still mark the lower bound as C<good> and the
464upper as C<bad>. The "first bad commit" has then to be understood as
465the "first commit where the bug is solved".
466
467C<git help bisect> has much more information on how you can tweak your
468binary searches.
469=head1 Topic branches and rewriting history
470
471Individual committers should create topic branches under
472B<yourname>/B<some_descriptive_name>. Other committers should check
473with a topic branch's creator before making any change to it.
474
475The simplest way to create a remote topic branch that works on all
476versions of git is to push the current head as a new branch on the
477remote, then check it out locally:
478
479 $ branch="$yourname/$some_descriptive_name"
480 $ git push origin HEAD:$branch
481 $ git checkout -b $branch origin/$branch
482
483Users of git 1.7 or newer can do it in a more obvious manner:
484
485 $ branch="$yourname/$some_descriptive_name"
486 $ git checkout -b $branch
487 $ git push origin -u $branch
488
489If you are not the creator of B<yourname>/B<some_descriptive_name>, you
490might sometimes find that the original author has edited the branch's
491history. There are lots of good reasons for this. Sometimes, an author
492might simply be rebasing the branch onto a newer source point.
493Sometimes, an author might have found an error in an early commit which
494they wanted to fix before merging the branch to blead.
495
496Currently the master repository is configured to forbid
497non-fast-forward merges. This means that the branches within can not be
498rebased and pushed as a single step.
499
500The only way you will ever be allowed to rebase or modify the history
501of a pushed branch is to delete it and push it as a new branch under
502the same name. Please think carefully about doing this. It may be
503better to sequentially rename your branches so that it is easier for
504others working with you to cherry-pick their local changes onto the new
505version. (XXX: needs explanation).
506
507If you want to rebase a personal topic branch, you will have to delete
508your existing topic branch and push as a new version of it. You can do
509this via the following formula (see the explanation about C<refspec>'s
510in the git push documentation for details) after you have rebased your
511branch:
512
513 # first rebase
514 $ git checkout $user/$topic
515 $ git fetch
516 $ git rebase origin/blead
517
518 # then "delete-and-push"
519 $ git push origin :$user/$topic
520 $ git push origin $user/$topic
521
522B<NOTE:> it is forbidden at the repository level to delete any of the
523"primary" branches. That is any branch matching
524C<m!^(blead|maint|perl)!>. Any attempt to do so will result in git
525producing an error like this:
526
527 $ git push origin :blead
528 *** It is forbidden to delete blead/maint branches in this repository
529 error: hooks/update exited with error code 1
530 error: hook declined to update refs/heads/blead
531 To ssh://perl5.git.perl.org/perl
532 ! [remote rejected] blead (hook declined)
533 error: failed to push some refs to 'ssh://perl5.git.perl.org/perl'
534
535As a matter of policy we do B<not> edit the history of the blead and
536maint-* branches. If a typo (or worse) sneaks into a commit to blead or
537maint-*, we'll fix it in another commit. The only types of updates
538allowed on these branches are "fast-forward's", where all history is
539preserved.
540
541Annotated tags in the canonical perl.git repository will never be
542deleted or modified. Think long and hard about whether you want to push
543a local tag to perl.git before doing so. (Pushing unannotated tags is
544not allowed.)
545
546=head3 Grafts
547
548The perl history contains one mistake which was not caught in the
549conversion: a merge was recorded in the history between blead and
550maint-5.10 where no merge actually occurred. Due to the nature of git,
551this is now impossible to fix in the public repository. You can remove
552this mis-merge locally by adding the following line to your
553C<.git/info/grafts> file:
554
555 296f12bbbbaa06de9be9d09d3dcf8f4528898a49 434946e0cb7a32589ed92d18008aaa1d88515930
556
557It is particularly important to have this graft line if any bisecting
558is done in the area of the "merge" in question.
559
560=head2 Topic branches and rewriting history
561
562Individual committers should create topic branches under
563B<yourname>/B<some_descriptive_name>. Other committers should check
564with a topic branch's creator before making any change to it.
565
566The simplest way to create a remote topic branch that works on all
567versions of git is to push the current head as a new branch on the
568remote, then check it out locally:
569
570 $ branch="$yourname/$some_descriptive_name"
571 $ git push origin HEAD:$branch
572 $ git checkout -b $branch origin/$branch
573
574Users of git 1.7 or newer can do it in a more obvious manner:
575
576 $ branch="$yourname/$some_descriptive_name"
577 $ git checkout -b $branch
578 $ git push origin -u $branch
579
580If you are not the creator of B<yourname>/B<some_descriptive_name>, you
581might sometimes find that the original author has edited the branch's
582history. There are lots of good reasons for this. Sometimes, an author
583might simply be rebasing the branch onto a newer source point.
584Sometimes, an author might have found an error in an early commit which
585they wanted to fix before merging the branch to blead.
586
587Currently the master repository is configured to forbid
588non-fast-forward merges. This means that the branches within can not be
589rebased and pushed as a single step.
590
591The only way you will ever be allowed to rebase or modify the history
592of a pushed branch is to delete it and push it as a new branch under
593the same name. Please think carefully about doing this. It may be
594better to sequentially rename your branches so that it is easier for
595others working with you to cherry-pick their local changes onto the new
596version. (XXX: needs explanation).
597
598If you want to rebase a personal topic branch, you will have to delete
599your existing topic branch and push as a new version of it. You can do
600this via the following formula (see the explanation about C<refspec>'s
601in the git push documentation for details) after you have rebased your
602branch:
603
604 # first rebase
605 $ git checkout $user/$topic
606 $ git fetch
607 $ git rebase origin/blead
608
609 # then "delete-and-push"
610 $ git push origin :$user/$topic
611 $ git push origin $user/$topic
612
613B<NOTE:> it is forbidden at the repository level to delete any of the
614"primary" branches. That is any branch matching
615C<m!^(blead|maint|perl)!>. Any attempt to do so will result in git
616producing an error like this:
617
618 $ git push origin :blead
619 *** It is forbidden to delete blead/maint branches in this repository
620 error: hooks/update exited with error code 1
621 error: hook declined to update refs/heads/blead
622 To ssh://perl5.git.perl.org/perl
623 ! [remote rejected] blead (hook declined)
624 error: failed to push some refs to 'ssh://perl5.git.perl.org/perl'
625
626As a matter of policy we do B<not> edit the history of the blead and
627maint-* branches. If a typo (or worse) sneaks into a commit to blead or
628maint-*, we'll fix it in another commit. The only types of updates
629allowed on these branches are "fast-forward's", where all history is
630preserved.
631
632Annotated tags in the canonical perl.git repository will never be
633deleted or modified. Think long and hard about whether you want to push
634a local tag to perl.git before doing so. (Pushing unannotated tags is
635not allowed.)
636
637=head1 WRITE ACCESS TO THE GIT REPOSITORY
638
639Once you have write access, you will need to modify the URL for the
640origin remote to enable pushing. Edit F<.git/config> with the
641git-config(1) command:
642
643 % git config remote.origin.url ssh://perl5.git.perl.org/perl.git
644
645You can also set up your user name and e-mail address. Most people do
646this once globally in their F<~/.gitconfig> by doing something like:
647
648 % git config --global user.name "Ævar Arnfjörð Bjarmason"
649 % git config --global user.email avarab@gmail.com
650
651However if you'd like to override that just for perl then execute then
652execute something like the following in F<perl>:
653
654 % git config user.email avar@cpan.org
655
656It is also possible to keep C<origin> as a git remote, and add a new
657remote for ssh access:
658
659 % git remote add camel perl5.git.perl.org:/perl.git
660
661This allows you to update your local repository by pulling from
662C<origin>, which is faster and doesn't require you to authenticate, and
663to push your changes back with the C<camel> remote:
664
665 % git fetch camel
666 % git push camel
667
668The C<fetch> command just updates the C<camel> refs, as the objects
669themselves should have been fetched when pulling from C<origin>.
670=head1 Accepting a patch
671
672If you have received a patch file generated using the above section,
673you should try out the patch.
674
675First we need to create a temporary new branch for these changes and
676switch into it:
677
678 % git checkout -b experimental
679
680Patches that were formatted by C<git format-patch> are applied with
681C<git am>:
682
683 % git am 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch
684 Applying Rename Leon Brocard to Orange Brocard
685
686If just a raw diff is provided, it is also possible use this two-step
687process:
688
689 % git apply bugfix.diff
690 % git commit -a -m "Some fixing" --author="That Guy <that.guy@internets.com>"
691
692Now we can inspect the change:
693
694 % git show HEAD
695 commit b1b3dab48344cff6de4087efca3dbd63548ab5e2
696 Author: Leon Brocard <acme@astray.com>
697 Date: Fri Dec 19 17:02:59 2008 +0000
698
699 Rename Leon Brocard to Orange Brocard
700
701 diff --git a/AUTHORS b/AUTHORS
702 index 293dd70..722c93e 100644
703 --- a/AUTHORS
704 +++ b/AUTHORS
705 @@ -541,7 +541,7 @@ Lars Hecking <lhecking@nmrc.ucc.ie>
706 Laszlo Molnar <laszlo.molnar@eth.ericsson.se>
707 Leif Huhn <leif@hale.dkstat.com>
708 Len Johnson <lenjay@ibm.net>
709 -Leon Brocard <acme@astray.com>
710 +Orange Brocard <acme@astray.com>
711 Les Peters <lpeters@aol.net>
712 Lesley Binks <lesley.binks@gmail.com>
713 Lincoln D. Stein <lstein@cshl.org>
714
715If you are a committer to Perl and you think the patch is good, you can
716then merge it into blead then push it out to the main repository:
717
718 % git checkout blead
719 % git merge experimental
720 % git push
721
722If you want to delete your temporary branch, you may do so with:
723
724 % git checkout blead
725 % git branch -d experimental
726 error: The branch 'experimental' is not an ancestor of your current HEAD.
727 If you are sure you want to delete it, run 'git branch -D experimental'.
728 % git branch -D experimental
729 Deleted branch experimental.
730
731=head2 Committing to blead
732
733The 'blead' branch will become the next production release of Perl.
734
735Before pushing I<any> local change to blead, it's incredibly important
736that you do a few things, lest other committers come after you with
737pitchforks and torches:
738
739=over
740
741=item *
742
743Make sure you have a good commit message. See L<perlhack/Commit
744message> for details.
745
746=item *
747
748Run the test suite. You might not think that one typo fix would break a
749test file. You'd be wrong. Here's an example of where not running the
750suite caused problems. A patch was submitted that added a couple of
751tests to an existing .t. It couldn't possibly affect anything else, so
752no need to test beyond the single affected .t, right? But, the
753submitter's email address had changed since the last of their
754submissions, and this caused other tests to fail. Running the test
755target given in the next item would have caught this problem.
756
757=item *
758
759If you don't run the full test suite, at least C<make test_porting>.
760This will run basic sanity checks. To see which sanity checks, have a
761look in F<t/porting>.
762
763=back
764
765=head2 Committing to maintenance versions
766
767Maintenance versions should only be altered to add critical bug fixes,
768see L<perlpolicy>.
769
770To commit to a maintenance version of perl, you need to create a local
771tracking branch:
772
773 % git checkout --track -b maint-5.005 origin/maint-5.005
774
775This creates a local branch named C<maint-5.005>, which tracks the
776remote branch C<origin/maint-5.005>. Then you can pull, commit, merge
777and push as before.
778
779You can also cherry-pick commits from blead and another branch, by
780using the C<git cherry-pick> command. It is recommended to use the
781B<-x> option to C<git cherry-pick> in order to record the SHA1 of the
782original commit in the new commit message.
783
784Before pushing any change to a maint version, make sure you've
785satisfied the steps in L</Committing to blead> above.
786
787=head2 Grafts
788
789The perl history contains one mistake which was not caught in the
790conversion: a merge was recorded in the history between blead and
791maint-5.10 where no merge actually occurred. Due to the nature of git,
792this is now impossible to fix in the public repository. You can remove
793this mis-merge locally by adding the following line to your
794C<.git/info/grafts> file:
795
796 296f12bbbbaa06de9be9d09d3dcf8f4528898a49 434946e0cb7a32589ed92d18008aaa1d88515930
797
798It is particularly important to have this graft line if any bisecting
799is done in the area of the "merge" in question.
800
801=head2 Merging from a branch via GitHub
802
803While we don't encourage the submission of patches via GitHub, that
804will still happen. Here is a guide to merging patches from a GitHub
805repository.
806
807 % git remote add avar git://github.com/avar/perl.git
808 % git fetch avar
809
810Now you can see the differences between the branch and blead:
811
812 % git diff avar/orange
813
814And you can see the commits:
815
816 % git log avar/orange
817
818If you approve of a specific commit, you can cherry pick it:
819
820 % git cherry-pick 0c24b290ae02b2ab3304f51d5e11e85eb3659eae
821
822Or you could just merge the whole branch if you like it all:
823
824 % git merge avar/orange
825
826And then push back to the repository:
827
828 % git push
829
830=head2 A note on camel and dromedary
831
832The committers have SSH access to the two servers that serve
833C<perl5.git.perl.org>. One is C<perl5.git.perl.org> itself (I<camel>),
834which is the 'master' repository. The second one is
835C<users.perl5.git.perl.org> (I<dromedary>), which can be used for
836general testing and development. Dromedary syncs the git tree from
837camel every few minutes, you should not push there. Both machines also
838have a full CPAN mirror in /srv/CPAN, please use this. To share files
839with the general public, dromedary serves your ~/public_html/ as
840C<http://users.perl5.git.perl.org/~yourlogin/>
841
842These hosts have fairly strict firewalls to the outside. Outgoing, only
843rsync, ssh and git are allowed. For http and ftp, you can use
844http://webproxy:3128 as proxy. Incoming, the firewall tries to detect
845attacks and blocks IP addresses with suspicious activity. This
846sometimes (but very rarely) has false positives and you might get
847blocked. The quickest way to get unblocked is to notify the admins.
848
849These two boxes are owned, hosted, and operated by booking.com. You can
850reach the sysadmins in #p5p on irc.perl.org or via mail to
851C<perl5-porters@perl.org>.