perlrepository
(1)
Name
perlrepository - Using the Perl source repository
Synopsis
All of Perl's source code is kept centrally in a Git
repository at perl5.git.perl.org. The repository contains
many Perl revisions from Perl 1 onwards and all the
revisions from Perforce, the version control system we were
using previously. This repository is accessible in different
ways.
The full repository takes up about 80MB of disk space. A
check out of the blead branch (that is, the main development
branch, which contains bleadperl, the development version of
perl 5) takes up about 160MB of disk space (including the
repository). A build of bleadperl takes up about 200MB
(including the repository and the check out).
Description
Perl Programmers Reference Guide PERLREPOSITORY(1)
NAME
perlrepository - Using the Perl source repository
SYNOPSIS
All of Perl's source code is kept centrally in a Git
repository at perl5.git.perl.org. The repository contains
many Perl revisions from Perl 1 onwards and all the
revisions from Perforce, the version control system we were
using previously. This repository is accessible in different
ways.
The full repository takes up about 80MB of disk space. A
check out of the blead branch (that is, the main development
branch, which contains bleadperl, the development version of
perl 5) takes up about 160MB of disk space (including the
repository). A build of bleadperl takes up about 200MB
(including the repository and the check out).
Getting access to the repository
Read access via the web
You may access the repository over the web. This allows you
to browse the tree, see recent commits, subscribe to RSS
feeds for the changes, search for particular commits and
more. You may access it at:
http://perl5.git.perl.org/perl.git
A mirror of the repository is found at:
http://github.com/mirrors/perl
Read access via Git
You will need a copy of Git for your computer. You can fetch
a copy of the repository using the Git protocol (which uses
port 9418):
% git clone git://perl5.git.perl.org/perl.git perl-git
This clones the repository and makes a local copy in the
perl-git directory.
If your local network does not allow you to use port 9418,
then you can fetch a copy of the repository over HTTP (this
is at least 4x slower):
% git clone http://perl5.git.perl.org/perl.git perl-http
This clones the repository and makes a local copy in the
perl-http directory.
Write access to the repository
If you are a committer, then you can fetch a copy of the
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repository that you can push back on with:
% git clone ssh://perl5.git.perl.org/perl.git perl-ssh
This clones the repository and makes a local copy in the
perl-ssh directory.
If you cloned using the git protocol, which is faster than
ssh, then you will need to modify the URL for the origin
remote to enable pushing. To do that edit .git/config with
git-config(1) like this:
% git config remote.origin.url ssh://perl5.git.perl.org/perl.git
You can also set up your user name and e-mail address. Most
people do this once globally in their ~/.gitconfig by doing
something like:
% git config --global user.name "A~Xvar ArnfjA~XrA~X Bjarmason"
% git config --global user.email [email protected]
However if you'd like to override that just for perl then
execute then execute something like the following in perl-
git:
% git config user.email [email protected]
It is also possible to keep "origin" as a git remote, and
add a new remote for ssh access:
% git remote add camel perl5.git.perl.org:/perl.git
This allows you to update your local repository by pulling
from "origin", which is faster and doesn't require you to
authenticate, and to push your changes back with the "camel"
remote:
% git fetch camel
% git push camel
The "fetch" command just updates the "camel" refs, as the
objects themselves should have been fetched when pulling
from "origin".
A note on camel and dromedary
The committers have SSH access to the two servers that serve
"perl5.git.perl.org". One is "perl5.git.perl.org" itself
(camel), which is the 'master' repository. The second one is
"users.perl5.git.perl.org" (dromedary), which can be used
for general testing and development. Dromedary syncs the git
tree from camel every few minutes, you should not push
there. Both machines also have a full CPAN mirror in
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/srv/CPAN, please use this. To share files with the general
public, dromedary serves your ~/public_html/ as
"http://users.perl5.git.perl.org/~yourlogin/"
These hosts have fairly strict firewalls to the outside.
Outgoing, only rsync, ssh and git are allowed. For http and
ftp, you can use http://webproxy:3128 as proxy. Incoming,
the firewall tries to detect attacks and blocks IP addresses
with suspicious activity. This sometimes (but very rarely)
has false positives and you might get blocked. The quickest
way to get unblocked is to notify the admins.
These two boxes are owned, hosted, and operated by
booking.com. You can reach the sysadmins in #p5p on
irc.perl.org or via mail to "[email protected]"
Overview of the repository
Once you have changed into the repository directory, you can
inspect it.
After a clone the repository will contain a single local
branch, which will be the current branch as well, as
indicated by the asterisk.
% git branch
* blead
Using the -a switch to "branch" will also show the remote
tracking branches in the repository:
% git branch -a
* blead
origin/HEAD
origin/blead
...
The branches that begin with "origin" correspond to the "git
remote" that you cloned from (which is named "origin"). Each
branch on the remote will be exactly tracked by theses
branches. You should NEVER do work on these remote tracking
branches. You only ever do work in a local branch. Local
branches can be configured to automerge (on pull) from a
designated remote tracking branch. This is the case with the
default branch "blead" which will be configured to merge
from the remote tracking branch "origin/blead".
You can see recent commits:
% git log
And pull new changes from the repository, and update your
local repository (must be clean first)
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% git pull
Assuming we are on the branch "blead" immediately after a
pull, this command would be more or less equivalent to:
% git fetch
% git merge origin/blead
In fact if you want to update your local repository without
touching your working directory you do:
% git fetch
And if you want to update your remote-tracking branches for
all defined remotes simultaneously you can do
% git remote update
Neither of these last two commands will update your working
directory, however both will update the remote-tracking
branches in your repository.
To make a local branch of a remote branch:
% git checkout -b maint-5.10 origin/maint-5.10
To switch back to blead:
% git checkout blead
Finding out your status
The most common git command you will use will probably be
% git status
This command will produce as output a description of the
current state of the repository, including modified files
and unignored untracked files, and in addition it will show
things like what files have been staged for the next commit,
and usually some useful information about how to change
things. For instance the following:
$ git status
# On branch blead
# Your branch is ahead of 'origin/blead' by 1 commit.
#
# Changes to be committed:
# (use "git reset HEAD <file>..." to unstage)
#
# modified: pod/perlrepository.pod
#
# Changed but not updated:
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# (use "git add <file>..." to update what will be committed)
#
# modified: pod/perlrepository.pod
#
# Untracked files:
# (use "git add <file>..." to include in what will be committed)
#
# deliberate.untracked
This shows that there were changes to this document staged
for commit, and that there were further changes in the
working directory not yet staged. It also shows that there
was an untracked file in the working directory, and as you
can see shows how to change all of this. It also shows that
there is one commit on the working branch "blead" which has
not been pushed to the "origin" remote yet. NOTE: that this
output is also what you see as a template if you do not
provide a message to "git commit".
Assuming that you'd like to commit all the changes you've
just made as a a single atomic unit, run this command:
% git commit -a
(That "-a" tells git to add every file you've changed to
this commit. New files aren't automatically added to your
commit when you use "commit -a" If you want to add files or
to commit some, but not all of your changes, have a look at
the documentation for "git add".)
Git will start up your favorite text editor, so that you can
craft a commit message for your change. See "Commit message"
below for more information about what makes a good commit
message.
Once you've finished writing your commit message and exited
your editor, git will write your change to disk and tell you
something like this:
Created commit daf8e63: explain git status and stuff about remotes
1 files changed, 83 insertions(+), 3 deletions(-)
If you re-run "git status", you should see something like
this:
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% git status
# On branch blead
# Your branch is ahead of 'origin/blead' by 2 commits.
#
# Untracked files:
# (use "git add <file>..." to include in what will be committed)
#
# deliberate.untracked
nothing added to commit but untracked files present (use "git add" to track)
When in doubt, before you do anything else, check your
status and read it carefully, many questions are answered
directly by the git status output.
Submitting a patch
If you have a patch in mind for Perl, you should first get a
copy of the repository:
% git clone git://perl5.git.perl.org/perl.git perl-git
Then change into the directory:
% cd perl-git
Alternatively, if you already have a Perl repository, you
should ensure that you're on the blead branch, and your
repository is up to date:
% git checkout blead
% git pull
It's preferable to patch against the latest blead version,
since this is where new development occurs for all changes
other than critical bug fixes. Critical bug fix patches
should be made against the relevant maint branches, or
should be submitted with a note indicating all the branches
where the fix should be applied.
Now that we have everything up to date, we need to create a
temporary new branch for these changes and switch into it:
% git checkout -b orange
which is the short form of
% git branch orange
% git checkout orange
Creating a topic branch makes it easier for the maintainers
to rebase or merge back into the master blead for a more
linear history. If you don't work on a topic branch the
maintainer has to manually cherry pick your changes onto
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blead before they can be applied.
That'll get you scolded on perl5-porters, so don't do that.
Be Awesome.
Then make your changes. For example, if Leon Brocard changes
his name to Orange Brocard, we should change his name in the
AUTHORS file:
% perl -pi -e 's{Leon Brocard}{Orange Brocard}' AUTHORS
You can see what files are changed:
% git status
# On branch orange
# Changes to be committed:
# (use "git reset HEAD <file>..." to unstage)
#
# modified: AUTHORS
#
And you can see the changes:
% git diff
diff --git a/AUTHORS b/AUTHORS
index 293dd70..722c93e 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -541,7 +541,7 @@ Lars Hecking <[email protected]>
Laszlo Molnar <[email protected]>
Leif Huhn <[email protected]>
Len Johnson <[email protected]>
-Leon Brocard <[email protected]>
+Orange Brocard <[email protected]>
Les Peters <[email protected]>
Lesley Binks <[email protected]>
Lincoln D. Stein <[email protected]>
Now commit your change locally:
% git commit -a -m 'Rename Leon Brocard to Orange Brocard'
Created commit 6196c1d: Rename Leon Brocard to Orange Brocard
1 files changed, 1 insertions(+), 1 deletions(-)
You can examine your last commit with:
% git show HEAD
and if you are not happy with either the description or the
patch itself you can fix it up by editing the files once
more and then issue:
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% git commit -a --amend
Now you should create a patch file for all your local
changes:
% git format-patch -M origin..
0001-Rename-Leon-Brocard-to-Orange-Brocard.patch
You should now send an email to to [email protected]
<mailto:[email protected]> with a description of your
changes, and include this patch file as an attachment. In
addition to being tracked by RT, mail to perlbug will
automatically be forwarded to perl5-porters. You should only
send patches to [email protected]
<mailto:[email protected]> directly if the patch is not
ready to be applied, but intended for discussion.
See the next section for how to configure and use git to
send these emails for you.
If you want to delete your temporary branch, you may do so
with:
% git checkout blead
% git branch -d orange
error: The branch 'orange' is not an ancestor of your current HEAD.
If you are sure you want to delete it, run 'git branch -D orange'.
% git branch -D orange
Deleted branch orange.
Using git to send patch emails
In your ~/git/perl repository, set the destination email to
perl's bug tracker:
$ git config sendemail.to [email protected]
Or maybe perl5-porters (discussed above):
$ git config sendemail.to [email protected]
Then you can use git directly to send your patch emails:
$ git send-email 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch
You may need to set some configuration variables for your
particular email service provider. For example, to set your
global git config to send email via a gmail account:
$ git config --global sendemail.smtpserver smtp.gmail.com
$ git config --global sendemail.smtpssl 1
$ git config --global sendemail.smtpuser [email protected]
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With this configuration, you will be prompted for your gmail
password when you run 'git send-email'. You can also
configure "sendemail.smtppass" with your password if you
don't care about having your password in the .gitconfig
file.
A note on derived files
Be aware that many files in the distribution are
derivative--avoid patching them, because git won't see the
changes to them, and the build process will overwrite them.
Patch the originals instead. Most utilities (like perldoc)
are in this category, i.e. patch utils/perldoc.PL rather
than utils/perldoc. Similarly, don't create patches for
files under $src_root/ext from their copies found in
$install_root/lib. If you are unsure about the proper
location of a file that may have gotten copied while
building the source distribution, consult the "MANIFEST".
As a special case, several files are regenerated by 'make
regen' if your patch alters "embed.fnc". These are needed
for compilation, but are included in the distribution so
that you can build perl without needing another perl to
generate the files. You must test with these regenerated
files, but it is preferred that you instead note that 'make
regen is needed' in both the email and the commit message,
and submit your patch without them. If you're submitting a
series of patches, it might be best to submit the
regenerated changes immediately after the source-changes
that caused them, so as to have as little effect as possible
on the bisectability of your patchset.
Getting your patch accepted
If you are submitting a code patch there are several things
that you need to do.
Commit message
As you craft each patch you intend to submit to the Perl
core, it's important to write a good commit message.
The first line of the commit message should be a short
description and should skip the full stop. It should be
no longer than the subject line of an E-Mail, 50
characters being a good rule of thumb.
A lot of Git tools (Gitweb, GitHub, git log
--pretty=oneline, ..) will only display the first line
(cut off at 50 characters) when presenting commit
summaries.
The commit message should include description of the
problem that the patch corrects or new functionality
that the patch adds.
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As a general rule of thumb, your commit message should
let a programmer with a reasonable familiarity with the
Perl core quickly understand what you were trying to do,
how you were trying to do it and why the change matters
to Perl.
What
Your commit message should describe what part of the
Perl core you're changing and what you expect your
patch to do.
Why Perhaps most importantly, your commit message should
describe why the change you are making is important.
When someone looks at your change in six months or
six years, your intent should be clear. If you're
deprecating a feature with the intent of later
simplifying another bit of code, say so. If you're
fixing a performance problem or adding a new feature
to support some other bit of the core, mention that.
How While it's not necessary for documentation changes,
new tests or trivial patches, it's often worth
explaining how your change works. Even if it's
clear to you today, it may not be clear to a porter
next month or next year.
A commit message isn't intended to take the place of
comments in your code. Commit messages should describe
the change you made, while code comments should describe
the current state of the code. If you've just
implemented a new feature, complete with doc, tests and
well-commented code, a brief commit message will often
suffice. If, however, you've just changed a single
character deep in the parser or lexer, you might need to
write a small novel to ensure that future readers
understand what you did and why you did it.
Comments, Comments, Comments
Be sure to adequately comment your code. While
commenting every line is unnecessary, anything that
takes advantage of side effects of operators, that
creates changes that will be felt outside of the
function being patched, or that others may find
confusing should be documented. If you are going to
err, it is better to err on the side of adding too many
comments than too few.
Style
In general, please follow the particular style of the
code you are patching.
In particular, follow these general guidelines for
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patching Perl sources:
8-wide tabs (no exceptions!)
4-wide indents for code, 2-wide indents for nested CPP #defines
try hard not to exceed 79-columns
ANSI C prototypes
uncuddled elses and "K&R" style for indenting control constructs
no C++ style (//) comments
mark places that need to be revisited with XXX (and revisit often!)
opening brace lines up with "if" when conditional spans multiple
lines; should be at end-of-line otherwise
in function definitions, name starts in column 0 (return value is on
previous line)
single space after keywords that are followed by parens, no space
between function name and following paren
avoid assignments in conditionals, but if they're unavoidable, use
extra paren, e.g. "if (a && (b = c)) ..."
"return foo;" rather than "return(foo);"
"if (!foo) ..." rather than "if (foo == FALSE) ..." etc.
Testsuite
If your patch changes code (rather than just changing
documentation) you should also include one or more test
cases which illustrate the bug you're fixing or validate
the new functionality you're adding. In general, you
should update an existing test file rather than create a
new one.
Your testsuite additions should generally follow these
guidelines (courtesy of Gurusamy Sarathy
<[email protected]>):
Know what you're testing. Read the docs, and the source.
Tend to fail, not succeed.
Interpret results strictly.
Use unrelated features (this will flush out bizarre interactions).
Use non-standard idioms (otherwise you are not testing TIMTOWTDI).
Avoid using hardcoded test numbers whenever possible (the
EXPECTED/GOT found in t/op/tie.t is much more maintainable,
and gives better failure reports).
Give meaningful error messages when a test fails.
Avoid using qx// and system() unless you are testing for them. If you
do use them, make sure that you cover _all_ perl platforms.
Unlink any temporary files you create.
Promote unforeseen warnings to errors with $SIG{__WARN__}.
Be sure to use the libraries and modules shipped with the version
being tested, not those that were already installed.
Add comments to the code explaining what you are testing for.
Make updating the '1..42' string unnecessary. Or make sure that
you update it.
Test _all_ behaviors of a given operator, library, or function:
- All optional arguments
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- Return values in various contexts (boolean, scalar, list, lvalue)
- Use both global and lexical variables
- Don't forget the exceptional, pathological cases.
Accepting a patch
If you have received a patch file generated using the above
section, you should try out the patch.
First we need to create a temporary new branch for these
changes and switch into it:
% git checkout -b experimental
Patches that were formatted by "git format-patch" are
applied with "git am":
% git am 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch
Applying Rename Leon Brocard to Orange Brocard
If just a raw diff is provided, it is also possible use this
two-step process:
% git apply bugfix.diff
% git commit -a -m "Some fixing" --author="That Guy <[email protected]>"
Now we can inspect the change:
% git show HEAD
commit b1b3dab48344cff6de4087efca3dbd63548ab5e2
Author: Leon Brocard <[email protected]>
Date: Fri Dec 19 17:02:59 2008 +0000
Rename Leon Brocard to Orange Brocard
diff --git a/AUTHORS b/AUTHORS
index 293dd70..722c93e 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -541,7 +541,7 @@ Lars Hecking <[email protected]>
Laszlo Molnar <[email protected]>
Leif Huhn <[email protected]>
Len Johnson <[email protected]>
-Leon Brocard <[email protected]>
+Orange Brocard <[email protected]>
Les Peters <[email protected]>
Lesley Binks <[email protected]>
Lincoln D. Stein <[email protected]>
If you are a committer to Perl and you think the patch is
good, you can then merge it into blead then push it out to
the main repository:
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% git checkout blead
% git merge experimental
% git push
If you want to delete your temporary branch, you may do so
with:
% git checkout blead
% git branch -d experimental
error: The branch 'experimental' is not an ancestor of your current HEAD.
If you are sure you want to delete it, run 'git branch -D experimental'.
% git branch -D experimental
Deleted branch experimental.
Cleaning a working directory
The command "git clean" can with varying arguments be used
as a replacement for "make clean".
To reset your working directory to a pristine condition you
can do:
% git clean -dxf
However, be aware this will delete ALL untracked content.
You can use
% git clean -Xf
to remove all ignored untracked files, such as build and
test byproduct, but leave any manually created files alone.
If you only want to cancel some uncommitted edits, you can
use "git checkout" and give it a list of files to be
reverted, or "git checkout -f" to revert them all.
If you want to cancel one or several commits, you can use
"git reset".
Bisecting
"git" provides a built-in way to determine, with a binary
search in the history, which commit should be blamed for
introducing a given bug.
Suppose that we have a script ~/testcase.pl that exits with
0 when some behaviour is correct, and with 1 when it's
faulty. You need an helper script that automates building
"perl" and running the testcase:
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% cat ~/run
#!/bin/sh
git clean -dxf
# If you can use ccache, add -Dcc=ccache\ gcc -Dld=gcc to the Configure line
# if Encode is not needed for the test, you can speed up the bisect by
# excluding it from the runs with -Dnoextensions=Encode
sh Configure -des -Dusedevel -Doptimize="-g"
test -f config.sh || exit 125
# Correct makefile for newer GNU gcc
perl -ni -we 'print unless /<(?:built-in|command)/' makefile x2p/makefile
# if you just need miniperl, replace test_prep with miniperl
make -j4 test_prep
[ -x ./perl ] || exit 125
./perl -Ilib ~/testcase.pl
ret=$?
[ $ret -gt 127 ] && ret=127
git clean -dxf
exit $ret
This script may return 125 to indicate that the
corresponding commit should be skipped. Otherwise, it
returns the status of ~/testcase.pl.
You first enter in bisect mode with:
% git bisect start
For example, if the bug is present on "HEAD" but wasn't in
5.10.0, "git" will learn about this when you enter:
% git bisect bad
% git bisect good perl-5.10.0
Bisecting: 853 revisions left to test after this
This results in checking out the median commit between
"HEAD" and "perl-5.10.0". You can then run the bisecting
process with:
% git bisect run ~/run
When the first bad commit is isolated, "git bisect" will
tell you so:
ca4cfd28534303b82a216cfe83a1c80cbc3b9dc5 is first bad commit
commit ca4cfd28534303b82a216cfe83a1c80cbc3b9dc5
Author: Dave Mitchell <[email protected]>
Date: Sat Feb 9 14:56:23 2008 +0000
[perl #49472] Attributes + Unknown Error
...
bisect run success
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You can peek into the bisecting process with "git bisect
log" and "git bisect visualize". "git bisect reset" will get
you out of bisect mode.
Please note that the first "good" state must be an ancestor
of the first "bad" state. If you want to search for the
commit that solved some bug, you have to negate your test
case (i.e. exit with 1 if OK and 0 if not) and still mark
the lower bound as "good" and the upper as "bad". The "first
bad commit" has then to be understood as the "first commit
where the bug is solved".
"git help bisect" has much more information on how you can
tweak your binary searches.
Submitting a patch via GitHub
GitHub is a website that makes it easy to fork and publish
projects with Git. First you should set up a GitHub account
and log in.
Perl's git repository is mirrored on GitHub at this page:
http://github.com/mirrors/perl/tree/blead
Visit the page and click the "fork" button. This clones the
Perl git repository for you and provides you with "Your
Clone URL" from which you should clone:
% git clone [email protected]:USERNAME/perl.git perl-github
The same patch as above, using github might look like this:
% cd perl-github
% git remote add upstream git://perl5.git.perl.org/perl.git
% git pull upstream blead
% git checkout -b orange
% perl -pi -e 's{Leon Brocard}{Orange Brocard}' AUTHORS
% git commit -a -m 'Rename Leon Brocard to Orange Brocard'
% git push origin orange
The orange branch has been pushed to GitHub, so you should
now send an email (see "Submitting a patch") with a
description of your changes and the following information:
http://github.com/USERNAME/perl/tree/orange
[email protected]:USERNAME/perl.git branch orange
Merging from a branch via GitHub
If someone has provided a branch via GitHub and you are a
committer, you should use the following in your perl-ssh
directory:
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% git remote add dandv git://github.com/dandv/perl.git
% git fetch dandv
Now you can see the differences between the branch and
blead:
% git diff dandv/blead
And you can see the commits:
% git log dandv/blead
If you approve of a specific commit, you can cherry pick it:
% git cherry-pick 3adac458cb1c1d41af47fc66e67b49c8dec2323f
Or you could just merge the whole branch if you like it all:
% git merge dandv/blead
And then push back to the repository:
% git push
Topic branches and rewriting history
Individual committers should create topic branches under
yourname/some_descriptive_name. Other committers should
check with a topic branch's creator before making any change
to it.
The simplest way to create a remote topic branch that works
on all versions of git is to push the current head as a new
branch on the remote, then check it out locally:
$ branch="$yourname/$some_descriptive_name"
$ git push origin HEAD:$branch
$ git checkout -b $branch origin/$branch
Users of git 1.7 or newer can do it in a more obvious
manner:
$ branch="$yourname/$some_descriptive_name"
$ git checkout -b $branch
$ git push origin -u $branch
If you are not the creator of
yourname/some_descriptive_name, you might sometimes find
that the original author has edited the branch's history.
There are lots of good reasons for this. Sometimes, an
author might simply be rebasing the branch onto a newer
source point. Sometimes, an author might have found an
error in an early commit which they wanted to fix before
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merging the branch to blead.
Currently the master repository is configured to forbid non-
fast-forward merges. This means that the branches within
can not be rebased and pushed as a single step.
The only way you will ever be allowed to rebase or modify
the history of a pushed branch is to delete it and push it
as a new branch under the same name. Please think carefully
about doing this. It may be better to sequentially rename
your branches so that it is easier for others working with
you to cherry-pick their local changes onto the new version.
(XXX: needs explanation).
If you want to rebase a personal topic branch, you will have
to delete your existing topic branch and push as a new
version of it. You can do this via the following formula
(see the explanation about "refspec"'s in the git push
documentation for details) after you have rebased your
branch:
# first rebase
$ git checkout $user/$topic
$ git fetch
$ git rebase origin/blead
# then "delete-and-push"
$ git push origin :$user/$topic
$ git push origin $user/$topic
NOTE: it is forbidden at the repository level to delete any
of the "primary" branches. That is any branch matching
"m!^(blead|maint|perl)!". Any attempt to do so will result
in git producing an error like this:
$ git push origin :blead
*** It is forbidden to delete blead/maint branches in this repository
error: hooks/update exited with error code 1
error: hook declined to update refs/heads/blead
To ssh://perl5.git.perl.org/perl
! [remote rejected] blead (hook declined)
error: failed to push some refs to 'ssh://perl5.git.perl.org/perl'
As a matter of policy we do not edit the history of the
blead and maint-* branches. If a typo (or worse) sneaks into
a commit to blead or maint-*, we'll fix it in another
commit. The only types of updates allowed on these branches
are "fast-forward's", where all history is preserved.
Annotated tags in the canonical perl.git repository will
never be deleted or modified. Think long and hard about
whether you want to push a local tag to perl.git before
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doing so. (Pushing unannotated tags is not allowed.)
Committing to maintenance versions
Maintenance versions should only be altered to add critical
bug fixes, see perlpolicy.
To commit to a maintenance version of perl, you need to
create a local tracking branch:
% git checkout --track -b maint-5.005 origin/maint-5.005
This creates a local branch named "maint-5.005", which
tracks the remote branch "origin/maint-5.005". Then you can
pull, commit, merge and push as before.
You can also cherry-pick commits from blead and another
branch, by using the "git cherry-pick" command. It is
recommended to use the -x option to "git cherry-pick" in
order to record the SHA1 of the original commit in the new
commit message.
Grafts
The perl history contains one mistake which was not caught
in the conversion: a merge was recorded in the history
between blead and maint-5.10 where no merge actually
occurred. Due to the nature of git, this is now impossible
to fix in the public repository. You can remove this mis-
merge locally by adding the following line to your
".git/info/grafts" file:
296f12bbbbaa06de9be9d09d3dcf8f4528898a49 434946e0cb7a32589ed92d18008aaa1d88515930
It is particularly important to have this graft line if any
bisecting is done in the area of the "merge" in question.
ATTRIBUTES
See attributes(5) for descriptions of the following
attributes:
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | runtime/perl-512 |
+---------------+------------------+
|Stability | Uncommitted |
+---------------+------------------+
SEE ALSO
o The git documentation, accessible via the "git help"
command
o perlpolicy - Perl core development policy
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NOTES
This software was built from source available at
https://java.net/projects/solaris-userland. The original
community source was downloaded from
http://www.cpan.org/src/5.0/perl-5.12.5.tar.bz2
Further information about this software can be found on the
open source community website at http://www.perl.org/.
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