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1 | =for comment |
2 | Consistent formatting of this file is achieved with: |
3 | perl ./Porting/podtidy pod/perlrepository.pod |
4 | |
d7dd28b6 |
5 | =head1 NAME |
6 | |
7 | perlrepository - Using the Perl source repository |
8 | |
9 | =head1 SYNOPSIS |
10 | |
dc3c3040 |
11 | All of Perl's source code is kept centrally in a Git repository at |
c26da522 |
12 | I<perl5.git.perl.org>. The repository contains many Perl revisions from |
13 | Perl 1 onwards and all the revisions from Perforce, the version control |
14 | system we were using previously. This repository is accessible in |
15 | different ways. |
d7dd28b6 |
16 | |
17 | The full repository takes up about 80MB of disk space. A check out of |
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18 | the blead branch (that is, the main development branch, which contains |
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19 | bleadperl, the development version of perl 5) takes up about 160MB of |
20 | disk space (including the repository). A build of bleadperl takes up |
21 | about 200MB (including the repository and the check out). |
d7dd28b6 |
22 | |
ba336be1 |
23 | =head1 Getting access to the repository |
d7dd28b6 |
24 | |
ba336be1 |
25 | =head2 Read access via the web |
d7dd28b6 |
26 | |
dc3c3040 |
27 | You may access the repository over the web. This allows you to browse |
28 | the tree, see recent commits, subscribe to RSS feeds for the changes, |
29 | search for particular commits and more. You may access it at: |
d7dd28b6 |
30 | |
31 | http://perl5.git.perl.org/perl.git |
32 | |
dc3c3040 |
33 | A mirror of the repository is found at: |
34 | |
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35 | http://github.com/mirrors/perl |
dc3c3040 |
36 | |
ba336be1 |
37 | =head2 Read access via Git |
d7dd28b6 |
38 | |
39 | You will need a copy of Git for your computer. You can fetch a copy of |
40 | the repository using the Git protocol (which uses port 9418): |
41 | |
e0b2b458 |
42 | % git clone git://perl5.git.perl.org/perl.git perl-git |
d7dd28b6 |
43 | |
f755e97d |
44 | This clones the repository and makes a local copy in the F<perl-git> |
d7dd28b6 |
45 | directory. |
46 | |
47 | If your local network does not allow you to use port 9418, then you can |
cf5e7595 |
48 | fetch a copy of the repository over HTTP (this is at least 4x slower): |
d7dd28b6 |
49 | |
e0b2b458 |
50 | % git clone http://perl5.git.perl.org/perl.git perl-http |
d7dd28b6 |
51 | |
f755e97d |
52 | This clones the repository and makes a local copy in the F<perl-http> |
d7dd28b6 |
53 | directory. |
54 | |
ba336be1 |
55 | =head2 Write access to the repository |
d7dd28b6 |
56 | |
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57 | If you are a committer, then you can fetch a copy of the repository |
58 | that you can push back on with: |
d7dd28b6 |
59 | |
e0b2b458 |
60 | % git clone ssh://perl5.git.perl.org/perl.git perl-ssh |
d7dd28b6 |
61 | |
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62 | This clones the repository and makes a local copy in the F<perl-ssh> |
d7dd28b6 |
63 | directory. |
64 | |
c26da522 |
65 | If you cloned using the git protocol, which is faster than ssh, then |
11ed6e28 |
66 | you will need to modify the URL for the origin remote to enable |
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67 | pushing. To do that edit F<.git/config> with git-config(1) like |
11ed6e28 |
68 | this: |
1a0f15d5 |
69 | |
e0b2b458 |
70 | % git config remote.origin.url ssh://perl5.git.perl.org/perl.git |
d7dd28b6 |
71 | |
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72 | You can also set up your user name and e-mail address. Most people do |
73 | this once globally in their F<~/.gitconfig> by doing something like: |
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74 | |
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75 | % git config --global user.name "Ævar Arnfjörð Bjarmason" |
76 | % git config --global user.email avarab@gmail.com |
77 | |
78 | However if you'd like to override that just for perl then execute then |
79 | execute something like the following in F<perl-git>: |
80 | |
81 | % git config user.email avar@cpan.org |
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82 | |
6acba58e |
83 | It is also possible to keep C<origin> as a git remote, and add a new |
84 | remote for ssh access: |
f6c12373 |
85 | |
dc3c3040 |
86 | % git remote add camel perl5.git.perl.org:/perl.git |
f6c12373 |
87 | |
6acba58e |
88 | This allows you to update your local repository by pulling from |
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89 | C<origin>, which is faster and doesn't require you to authenticate, and |
6acba58e |
90 | to push your changes back with the C<camel> remote: |
f6c12373 |
91 | |
92 | % git fetch camel |
93 | % git push camel |
94 | |
6acba58e |
95 | The C<fetch> command just updates the C<camel> refs, as the objects |
96 | themselves should have been fetched when pulling from C<origin>. |
f6c12373 |
97 | |
ba336be1 |
98 | =head2 A note on camel and dromedary |
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99 | |
100 | The committers have SSH access to the two servers that serve |
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101 | C<perl5.git.perl.org>. One is C<perl5.git.perl.org> itself (I<camel>), |
102 | which is the 'master' repository. The second one is |
103 | C<users.perl5.git.perl.org> (I<dromedary>), which can be used for |
104 | general testing and development. Dromedary syncs the git tree from |
105 | camel every few minutes, you should not push there. Both machines also |
3482f01a |
106 | have a full CPAN mirror in /srv/CPAN, please use this. To share files |
107 | with the general public, dromedary serves your ~/public_html/ as |
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108 | C<http://users.perl5.git.perl.org/~yourlogin/> |
b47aa495 |
109 | |
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110 | These hosts have fairly strict firewalls to the outside. Outgoing, only |
111 | rsync, ssh and git are allowed. For http and ftp, you can use |
112 | http://webproxy:3128 as proxy. Incoming, the firewall tries to detect |
113 | attacks and blocks IP addresses with suspicious activity. This |
114 | sometimes (but very rarely) has false positives and you might get |
115 | blocked. The quickest way to get unblocked is to notify the admins. |
116 | |
117 | These two boxes are owned, hosted, and operated by booking.com. You can |
118 | reach the sysadmins in #p5p on irc.perl.org or via mail to |
119 | C<perl5-porters@perl.org> |
120 | |
ba336be1 |
121 | =head1 Overview of the repository |
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122 | |
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123 | Once you have changed into the repository directory, you can inspect |
124 | it. |
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125 | |
39219fd3 |
126 | After a clone the repository will contain a single local branch, which |
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127 | will be the current branch as well, as indicated by the asterisk. |
39219fd3 |
128 | |
129 | % git branch |
130 | * blead |
131 | |
f755e97d |
132 | Using the -a switch to C<branch> will also show the remote tracking |
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133 | branches in the repository: |
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134 | |
d9847473 |
135 | % git branch -a |
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136 | * blead |
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137 | origin/HEAD |
138 | origin/blead |
139 | ... |
140 | |
6acba58e |
141 | The branches that begin with "origin" correspond to the "git remote" |
142 | that you cloned from (which is named "origin"). Each branch on the |
143 | remote will be exactly tracked by theses branches. You should NEVER do |
144 | work on these remote tracking branches. You only ever do work in a |
145 | local branch. Local branches can be configured to automerge (on pull) |
146 | from a designated remote tracking branch. This is the case with the |
147 | default branch C<blead> which will be configured to merge from the |
148 | remote tracking branch C<origin/blead>. |
39219fd3 |
149 | |
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150 | You can see recent commits: |
151 | |
c2cf2042 |
152 | % git log |
d7dd28b6 |
153 | |
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154 | And pull new changes from the repository, and update your local |
155 | repository (must be clean first) |
d7dd28b6 |
156 | |
157 | % git pull |
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158 | |
6acba58e |
159 | Assuming we are on the branch C<blead> immediately after a pull, this |
160 | command would be more or less equivalent to: |
39219fd3 |
161 | |
162 | % git fetch |
163 | % git merge origin/blead |
164 | |
6acba58e |
165 | In fact if you want to update your local repository without touching |
166 | your working directory you do: |
39219fd3 |
167 | |
168 | % git fetch |
169 | |
6acba58e |
170 | And if you want to update your remote-tracking branches for all defined |
171 | remotes simultaneously you can do |
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172 | |
173 | % git remote update |
174 | |
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175 | Neither of these last two commands will update your working directory, |
176 | however both will update the remote-tracking branches in your |
177 | repository. |
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178 | |
6051489b |
179 | To make a local branch of a remote branch: |
180 | |
181 | % git checkout -b maint-5.10 origin/maint-5.10 |
182 | |
09081495 |
183 | To switch back to blead: |
184 | |
185 | % git checkout blead |
c2cf2042 |
186 | |
ba336be1 |
187 | =head2 Finding out your status |
39219fd3 |
188 | |
189 | The most common git command you will use will probably be |
190 | |
191 | % git status |
192 | |
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193 | This command will produce as output a description of the current state |
194 | of the repository, including modified files and unignored untracked |
195 | files, and in addition it will show things like what files have been |
196 | staged for the next commit, and usually some useful information about |
197 | how to change things. For instance the following: |
39219fd3 |
198 | |
199 | $ git status |
200 | # On branch blead |
201 | # Your branch is ahead of 'origin/blead' by 1 commit. |
202 | # |
203 | # Changes to be committed: |
204 | # (use "git reset HEAD <file>..." to unstage) |
205 | # |
206 | # modified: pod/perlrepository.pod |
207 | # |
208 | # Changed but not updated: |
209 | # (use "git add <file>..." to update what will be committed) |
210 | # |
211 | # modified: pod/perlrepository.pod |
212 | # |
213 | # Untracked files: |
214 | # (use "git add <file>..." to include in what will be committed) |
215 | # |
216 | # deliberate.untracked |
217 | |
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218 | This shows that there were changes to this document staged for commit, |
219 | and that there were further changes in the working directory not yet |
220 | staged. It also shows that there was an untracked file in the working |
221 | directory, and as you can see shows how to change all of this. It also |
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222 | shows that there is one commit on the working branch C<blead> which has |
223 | not been pushed to the C<origin> remote yet. B<NOTE>: that this output |
224 | is also what you see as a template if you do not provide a message to |
225 | C<git commit>. |
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226 | |
bdaf0bc6 |
227 | Assuming that you'd like to commit all the changes you've just made as a |
228 | a single atomic unit, run this command: |
229 | |
230 | % git commit -a |
231 | |
232 | (That C<-a> tells git to add every file you've changed to this commit. |
ea9c0d74 |
233 | New files aren't automatically added to your commit when you use C<commit |
234 | -a> If you want to add files or to commit some, but not all of your |
235 | changes, have a look at the documentation for C<git add>.) |
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236 | |
e9360695 |
237 | Git will start up your favorite text editor, so that you can craft a |
bdaf0bc6 |
238 | commit message for your change. See L</Commit message> below for more |
239 | information about what makes a good commit message. |
240 | |
241 | Once you've finished writing your commit message and exited your editor, |
242 | git will write your change to disk and tell you something like this: |
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243 | |
7f6effc7 |
244 | Created commit daf8e63: explain git status and stuff about remotes |
245 | 1 files changed, 83 insertions(+), 3 deletions(-) |
246 | |
bdaf0bc6 |
247 | |
248 | If you re-run C<git status>, you should see something like this: |
7f6effc7 |
249 | |
250 | % git status |
251 | # On branch blead |
252 | # Your branch is ahead of 'origin/blead' by 2 commits. |
253 | # |
254 | # Untracked files: |
255 | # (use "git add <file>..." to include in what will be committed) |
256 | # |
257 | # deliberate.untracked |
258 | nothing added to commit but untracked files present (use "git add" to track) |
259 | |
39219fd3 |
260 | |
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261 | When in doubt, before you do anything else, check your status and read |
262 | it carefully, many questions are answered directly by the git status |
263 | output. |
39219fd3 |
264 | |
ba336be1 |
265 | =head1 Submitting a patch |
c2cf2042 |
266 | |
267 | If you have a patch in mind for Perl, you should first get a copy of |
268 | the repository: |
269 | |
270 | % git clone git://perl5.git.perl.org/perl.git perl-git |
271 | |
272 | Then change into the directory: |
273 | |
274 | % cd perl-git |
275 | |
6acba58e |
276 | Alternatively, if you already have a Perl repository, you should ensure |
277 | that you're on the I<blead> branch, and your repository is up to date: |
12322d22 |
278 | |
279 | % git checkout blead |
280 | % git pull |
281 | |
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282 | It's preferable to patch against the latest blead version, since this |
283 | is where new development occurs for all changes other than critical bug |
284 | fixes. Critical bug fix patches should be made against the relevant |
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285 | maint branches, or should be submitted with a note indicating all the |
286 | branches where the fix should be applied. |
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287 | |
6acba58e |
288 | Now that we have everything up to date, we need to create a temporary |
289 | new branch for these changes and switch into it: |
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290 | |
a9b05323 |
291 | % git checkout -b orange |
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292 | |
a9b05323 |
293 | which is the short form of |
294 | |
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295 | % git branch orange |
296 | % git checkout orange |
297 | |
0c24b290 |
298 | Creating a topic branch makes it easier for the maintainers to rebase |
299 | or merge back into the master blead for a more linear history. If you |
300 | don't work on a topic branch the maintainer has to manually cherry |
301 | pick your changes onto blead before they can be applied. |
302 | |
303 | That'll get you scolded on perl5-porters, so don't do that. Be |
304 | Awesome. |
305 | |
c2cf2042 |
306 | Then make your changes. For example, if Leon Brocard changes his name |
307 | to Orange Brocard, we should change his name in the AUTHORS file: |
308 | |
309 | % perl -pi -e 's{Leon Brocard}{Orange Brocard}' AUTHORS |
310 | |
311 | You can see what files are changed: |
312 | |
313 | % git status |
f755e97d |
314 | # On branch orange |
c2cf2042 |
315 | # Changes to be committed: |
316 | # (use "git reset HEAD <file>..." to unstage) |
317 | # |
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318 | # modified: AUTHORS |
c2cf2042 |
319 | # |
320 | |
c2cf2042 |
321 | And you can see the changes: |
322 | |
323 | % git diff |
324 | diff --git a/AUTHORS b/AUTHORS |
325 | index 293dd70..722c93e 100644 |
326 | --- a/AUTHORS |
327 | +++ b/AUTHORS |
7df2e4bc |
328 | @@ -541,7 +541,7 @@ Lars Hecking <lhecking@nmrc.ucc.ie> |
c2cf2042 |
329 | Laszlo Molnar <laszlo.molnar@eth.ericsson.se> |
330 | Leif Huhn <leif@hale.dkstat.com> |
331 | Len Johnson <lenjay@ibm.net> |
332 | -Leon Brocard <acme@astray.com> |
333 | +Orange Brocard <acme@astray.com> |
334 | Les Peters <lpeters@aol.net> |
335 | Lesley Binks <lesley.binks@gmail.com> |
336 | Lincoln D. Stein <lstein@cshl.org> |
337 | |
338 | Now commit your change locally: |
339 | |
dc3c3040 |
340 | % git commit -a -m 'Rename Leon Brocard to Orange Brocard' |
c2cf2042 |
341 | Created commit 6196c1d: Rename Leon Brocard to Orange Brocard |
342 | 1 files changed, 1 insertions(+), 1 deletions(-) |
343 | |
dc3c3040 |
344 | You can examine your last commit with: |
345 | |
346 | % git show HEAD |
347 | |
348 | and if you are not happy with either the description or the patch |
c26da522 |
349 | itself you can fix it up by editing the files once more and then issue: |
dc3c3040 |
350 | |
351 | % git commit -a --amend |
352 | |
c2cf2042 |
353 | Now you should create a patch file for all your local changes: |
354 | |
f15b1f22 |
355 | % git format-patch -M origin.. |
c2cf2042 |
356 | 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch |
357 | |
64a8e22b |
358 | You should now send an email to either perlbug@perl.org or |
359 | perl5-porters@perl.org with a description of your changes, and include |
360 | this patch file as an attachment. The perlbug address is preferred, |
361 | but use perl5-porters for patches intended for discussion. |
362 | |
363 | See the next section for how to configure and use git to send these |
364 | emails for you. |
c2cf2042 |
365 | |
b1fccde5 |
366 | If you want to delete your temporary branch, you may do so with: |
367 | |
368 | % git checkout blead |
369 | % git branch -d orange |
370 | error: The branch 'orange' is not an ancestor of your current HEAD. |
371 | If you are sure you want to delete it, run 'git branch -D orange'. |
372 | % git branch -D orange |
373 | Deleted branch orange. |
7df2e4bc |
374 | |
2d5f1d01 |
375 | =head2 Using git to send patch emails |
376 | |
64a8e22b |
377 | In your ~/git/perl repository, set the destination email to perl's bug |
378 | tracker: |
379 | |
380 | $ git config sendemail.to perlbug@perl.org |
381 | |
382 | Or maybe perl5-porters (discussed above): |
2d5f1d01 |
383 | |
384 | $ git config sendemail.to perl5-porters@perl.org |
385 | |
386 | Then you can use git directly to send your patch emails: |
387 | |
388 | $ git send-email 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch |
389 | |
333f8875 |
390 | You may need to set some configuration variables for your particular |
391 | email service provider. For example, to set your global git config to |
392 | send email via a gmail account: |
2d5f1d01 |
393 | |
394 | $ git config --global sendemail.smtpserver smtp.gmail.com |
395 | $ git config --global sendemail.smtpssl 1 |
396 | $ git config --global sendemail.smtpuser YOURUSERNAME@gmail.com |
397 | |
333f8875 |
398 | With this configuration, you will be prompted for your gmail password |
399 | when you run 'git send-email'. You can also configure |
400 | C<sendemail.smtppass> with your password if you don't care about having |
401 | your password in the .gitconfig file. |
2d5f1d01 |
402 | |
a44f43ac |
403 | =head2 A note on derived files |
404 | |
405 | Be aware that many files in the distribution are derivative--avoid |
0549aefb |
406 | patching them, because git won't see the changes to them, and the build |
407 | process will overwrite them. Patch the originals instead. Most |
408 | utilities (like perldoc) are in this category, i.e. patch |
0be741b5 |
409 | F<utils/perldoc.PL> rather than F<utils/perldoc>. Similarly, don't create |
0549aefb |
410 | patches for files under $src_root/ext from their copies found in |
411 | $install_root/lib. If you are unsure about the proper location of a |
412 | file that may have gotten copied while building the source |
413 | distribution, consult the C<MANIFEST>. |
a44f43ac |
414 | |
ac1cbfb0 |
415 | As a special case, several files are regenerated by 'make regen' if |
416 | your patch alters C<embed.fnc>. These are needed for compilation, but |
417 | are included in the distribution so that you can build perl without |
418 | needing another perl to generate the files. You must test with these |
419 | regenerated files, but it is preferred that you instead note that |
420 | 'make regen is needed' in both the email and the commit message, and |
421 | submit your patch without them. If you're submitting a series of |
422 | patches, it might be best to submit the regenerated changes |
423 | immediately after the source-changes that caused them, so as to have |
424 | as little effect as possible on the bisectability of your patchset. |
425 | |
6e2cec71 |
426 | =for XXX |
a44f43ac |
427 | |
6e2cec71 |
428 | What should we recommend about binary files now? Do we need anything? |
a44f43ac |
429 | |
430 | =head2 Getting your patch accepted |
431 | |
bdaf0bc6 |
432 | If you are submitting a code patch there are several things that |
a44f43ac |
433 | you need to do. |
434 | |
435 | =over 4 |
436 | |
bdaf0bc6 |
437 | =item Commit message |
438 | |
439 | As you craft each patch you intend to submit to the Perl core, it's |
440 | important to write a good commit message. |
441 | |
1a5f98ea |
442 | The first line of the commit message should be a short description and |
443 | should skip the full stop. It should be no longer than the subject |
444 | line of an E-Mail, 50 characters being a good rule of thumb. |
445 | |
446 | A lot of Git tools (Gitweb, GitHub, git log --pretty=oneline, ..) will |
447 | only display the first line (cut off at 50 characters) when presenting |
448 | commit summaries. |
449 | |
450 | The commit message should include description of the problem that the |
451 | patch corrects or new functionality that the patch adds. |
bdaf0bc6 |
452 | |
bdaf0bc6 |
453 | As a general rule of thumb, your commit message should let a programmer |
454 | with a reasonable familiarity with the Perl core quickly understand what |
455 | you were trying to do, how you were trying to do it and why the change |
456 | matters to Perl. |
457 | |
458 | =over 4 |
459 | |
460 | =item What |
461 | |
ac1cbfb0 |
462 | Your commit message should describe what part of the Perl core you're |
463 | changing and what you expect your patch to do. |
bdaf0bc6 |
464 | |
465 | =item Why |
466 | |
467 | Perhaps most importantly, your commit message should describe why the |
468 | change you are making is important. When someone looks at your change |
469 | in six months or six years, your intent should be clear. If you're |
470 | deprecating a feature with the intent of later simplifying another bit |
471 | of code, say so. If you're fixing a performance problem or adding a new |
472 | feature to support some other bit of the core, mention that. |
473 | |
474 | =item How |
475 | |
476 | While it's not necessary for documentation changes, new tests or |
477 | trivial patches, it's often worth explaining how your change works. |
478 | Even if it's clear to you today, it may not be clear to a porter next |
479 | month or next year. |
480 | |
481 | =back |
482 | |
ea9c0d74 |
483 | A commit message isn't intended to take the place of comments in your |
484 | code. Commit messages should describe the change you made, while code |
80a0006a |
485 | comments should describe the current state of the code. If you've just |
486 | implemented a new feature, complete with doc, tests and well-commented |
487 | code, a brief commit message will often suffice. If, however, you've |
488 | just changed a single character deep in the parser or lexer, you might |
ea9c0d74 |
489 | need to write a small novel to ensure that future readers understand |
490 | what you did and why you did it. |
491 | |
a44f43ac |
492 | =item Comments, Comments, Comments |
493 | |
0549aefb |
494 | Be sure to adequately comment your code. While commenting every line |
495 | is unnecessary, anything that takes advantage of side effects of |
a44f43ac |
496 | operators, that creates changes that will be felt outside of the |
0549aefb |
497 | function being patched, or that others may find confusing should be |
498 | documented. If you are going to err, it is better to err on the side |
499 | of adding too many comments than too few. |
a44f43ac |
500 | |
501 | =item Style |
502 | |
0549aefb |
503 | In general, please follow the particular style of the code you are |
504 | patching. |
a44f43ac |
505 | |
0549aefb |
506 | In particular, follow these general guidelines for patching Perl |
507 | sources: |
a44f43ac |
508 | |
509 | 8-wide tabs (no exceptions!) |
510 | 4-wide indents for code, 2-wide indents for nested CPP #defines |
511 | try hard not to exceed 79-columns |
512 | ANSI C prototypes |
513 | uncuddled elses and "K&R" style for indenting control constructs |
514 | no C++ style (//) comments |
515 | mark places that need to be revisited with XXX (and revisit often!) |
516 | opening brace lines up with "if" when conditional spans multiple |
517 | lines; should be at end-of-line otherwise |
518 | in function definitions, name starts in column 0 (return value is on |
519 | previous line) |
520 | single space after keywords that are followed by parens, no space |
521 | between function name and following paren |
522 | avoid assignments in conditionals, but if they're unavoidable, use |
523 | extra paren, e.g. "if (a && (b = c)) ..." |
524 | "return foo;" rather than "return(foo);" |
525 | "if (!foo) ..." rather than "if (foo == FALSE) ..." etc. |
526 | |
527 | =item Testsuite |
528 | |
bdaf0bc6 |
529 | If your patch changes code (rather than just changing documentation) you |
530 | should also include one or more test cases which illustrate the bug you're |
531 | fixing or validate the new functionality you're adding. In general, |
532 | you should update an existing test file rather than create a new one. |
533 | |
0549aefb |
534 | Your testsuite additions should generally follow these guidelines |
535 | (courtesy of Gurusamy Sarathy <gsar@activestate.com>): |
a44f43ac |
536 | |
537 | Know what you're testing. Read the docs, and the source. |
538 | Tend to fail, not succeed. |
539 | Interpret results strictly. |
540 | Use unrelated features (this will flush out bizarre interactions). |
541 | Use non-standard idioms (otherwise you are not testing TIMTOWTDI). |
542 | Avoid using hardcoded test numbers whenever possible (the |
543 | EXPECTED/GOT found in t/op/tie.t is much more maintainable, |
544 | and gives better failure reports). |
545 | Give meaningful error messages when a test fails. |
546 | Avoid using qx// and system() unless you are testing for them. If you |
547 | do use them, make sure that you cover _all_ perl platforms. |
548 | Unlink any temporary files you create. |
549 | Promote unforeseen warnings to errors with $SIG{__WARN__}. |
550 | Be sure to use the libraries and modules shipped with the version |
551 | being tested, not those that were already installed. |
552 | Add comments to the code explaining what you are testing for. |
553 | Make updating the '1..42' string unnecessary. Or make sure that |
554 | you update it. |
555 | Test _all_ behaviors of a given operator, library, or function: |
556 | - All optional arguments |
557 | - Return values in various contexts (boolean, scalar, list, lvalue) |
558 | - Use both global and lexical variables |
559 | - Don't forget the exceptional, pathological cases. |
560 | |
561 | =back |
562 | |
ba336be1 |
563 | =head1 Accepting a patch |
7df2e4bc |
564 | |
565 | If you have received a patch file generated using the above section, |
566 | you should try out the patch. |
567 | |
568 | First we need to create a temporary new branch for these changes and |
569 | switch into it: |
570 | |
a9b05323 |
571 | % git checkout -b experimental |
7df2e4bc |
572 | |
6acba58e |
573 | Patches that were formatted by C<git format-patch> are applied with |
574 | C<git am>: |
7df2e4bc |
575 | |
2af192ee |
576 | % git am 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch |
7df2e4bc |
577 | Applying Rename Leon Brocard to Orange Brocard |
578 | |
6acba58e |
579 | If just a raw diff is provided, it is also possible use this two-step |
580 | process: |
09645c26 |
581 | |
582 | % git apply bugfix.diff |
dc3c3040 |
583 | % git commit -a -m "Some fixing" --author="That Guy <that.guy@internets.com>" |
09645c26 |
584 | |
7df2e4bc |
585 | Now we can inspect the change: |
586 | |
dc3c3040 |
587 | % git show HEAD |
7df2e4bc |
588 | commit b1b3dab48344cff6de4087efca3dbd63548ab5e2 |
589 | Author: Leon Brocard <acme@astray.com> |
590 | Date: Fri Dec 19 17:02:59 2008 +0000 |
591 | |
592 | Rename Leon Brocard to Orange Brocard |
7df2e4bc |
593 | |
7df2e4bc |
594 | diff --git a/AUTHORS b/AUTHORS |
595 | index 293dd70..722c93e 100644 |
596 | --- a/AUTHORS |
597 | +++ b/AUTHORS |
598 | @@ -541,7 +541,7 @@ Lars Hecking <lhecking@nmrc.ucc.ie> |
599 | Laszlo Molnar <laszlo.molnar@eth.ericsson.se> |
600 | Leif Huhn <leif@hale.dkstat.com> |
601 | Len Johnson <lenjay@ibm.net> |
602 | -Leon Brocard <acme@astray.com> |
603 | +Orange Brocard <acme@astray.com> |
604 | Les Peters <lpeters@aol.net> |
605 | Lesley Binks <lesley.binks@gmail.com> |
606 | Lincoln D. Stein <lstein@cshl.org> |
607 | |
608 | If you are a committer to Perl and you think the patch is good, you can |
75fb7651 |
609 | then merge it into blead then push it out to the main repository: |
7df2e4bc |
610 | |
611 | % git checkout blead |
d9847473 |
612 | % git merge experimental |
75fb7651 |
613 | % git push |
7df2e4bc |
614 | |
615 | If you want to delete your temporary branch, you may do so with: |
616 | |
617 | % git checkout blead |
618 | % git branch -d experimental |
619 | error: The branch 'experimental' is not an ancestor of your current HEAD. |
620 | If you are sure you want to delete it, run 'git branch -D experimental'. |
621 | % git branch -D experimental |
622 | Deleted branch experimental. |
b0d36535 |
623 | |
ba336be1 |
624 | =head1 Cleaning a working directory |
b0d36535 |
625 | |
6acba58e |
626 | The command C<git clean> can with varying arguments be used as a |
dc3c3040 |
627 | replacement for C<make clean>. |
b0d36535 |
628 | |
629 | To reset your working directory to a pristine condition you can do: |
630 | |
e0b2b458 |
631 | % git clean -dxf |
b0d36535 |
632 | |
633 | However, be aware this will delete ALL untracked content. You can use |
634 | |
e0b2b458 |
635 | % git clean -Xf |
b0d36535 |
636 | |
6acba58e |
637 | to remove all ignored untracked files, such as build and test |
638 | byproduct, but leave any manually created files alone. |
b0d36535 |
639 | |
0549aefb |
640 | If you only want to cancel some uncommitted edits, you can use C<git |
c26da522 |
641 | checkout> and give it a list of files to be reverted, or C<git checkout |
642 | -f> to revert them all. |
f755e97d |
643 | |
644 | If you want to cancel one or several commits, you can use C<git reset>. |
645 | |
ba336be1 |
646 | =head1 Bisecting |
d82a90c1 |
647 | |
6acba58e |
648 | C<git> provides a built-in way to determine, with a binary search in |
649 | the history, which commit should be blamed for introducing a given bug. |
d82a90c1 |
650 | |
6acba58e |
651 | Suppose that we have a script F<~/testcase.pl> that exits with C<0> |
bdaf0bc6 |
652 | when some behaviour is correct, and with C<1> when it's faulty. You need |
6acba58e |
653 | an helper script that automates building C<perl> and running the |
654 | testcase: |
d82a90c1 |
655 | |
656 | % cat ~/run |
657 | #!/bin/sh |
658 | git clean -dxf |
a4583001 |
659 | |
660 | # If you get './makedepend: 1: Syntax error: Unterminated quoted |
661 | # string' when bisecting versions of perl older than 5.9.5 this hack |
662 | # will work around the bug in makedepend.SH which was fixed in |
cfe91bfa |
663 | # version 96a8704c. Make sure to comment out `git checkout makedepend.SH' |
a4583001 |
664 | # below too. |
665 | git show blead:makedepend.SH > makedepend.SH |
666 | |
d82a90c1 |
667 | # If you can use ccache, add -Dcc=ccache\ gcc -Dld=gcc to the Configure line |
1d5fe431 |
668 | # if Encode is not needed for the test, you can speed up the bisect by |
669 | # excluding it from the runs with -Dnoextensions=Encode |
c0d1ef72 |
670 | sh Configure -des -Dusedevel -Doptimize="-g" |
671 | test -f config.sh || exit 125 |
672 | # Correct makefile for newer GNU gcc |
673 | perl -ni -we 'print unless /<(?:built-in|command)/' makefile x2p/makefile |
674 | # if you just need miniperl, replace test_prep with miniperl |
d7923bfe |
675 | make test_prep |
68814ba4 |
676 | [ -x ./perl ] || exit 125 |
d82a90c1 |
677 | ./perl -Ilib ~/testcase.pl |
c0d1ef72 |
678 | ret=$? |
7930c68b |
679 | [ $ret -gt 127 ] && ret=127 |
cfe91bfa |
680 | # git checkout makedepend.SH |
c0d1ef72 |
681 | git clean -dxf |
682 | exit $ret |
d82a90c1 |
683 | |
6acba58e |
684 | This script may return C<125> to indicate that the corresponding commit |
685 | should be skipped. Otherwise, it returns the status of |
686 | F<~/testcase.pl>. |
d82a90c1 |
687 | |
bdaf0bc6 |
688 | You first enter in bisect mode with: |
d82a90c1 |
689 | |
690 | % git bisect start |
691 | |
6acba58e |
692 | For example, if the bug is present on C<HEAD> but wasn't in 5.10.0, |
693 | C<git> will learn about this when you enter: |
d82a90c1 |
694 | |
695 | % git bisect bad |
696 | % git bisect good perl-5.10.0 |
697 | Bisecting: 853 revisions left to test after this |
698 | |
6acba58e |
699 | This results in checking out the median commit between C<HEAD> and |
bdaf0bc6 |
700 | C<perl-5.10.0>. You can then run the bisecting process with: |
d82a90c1 |
701 | |
702 | % git bisect run ~/run |
703 | |
704 | When the first bad commit is isolated, C<git bisect> will tell you so: |
705 | |
706 | ca4cfd28534303b82a216cfe83a1c80cbc3b9dc5 is first bad commit |
707 | commit ca4cfd28534303b82a216cfe83a1c80cbc3b9dc5 |
708 | Author: Dave Mitchell <davem@fdisolutions.com> |
709 | Date: Sat Feb 9 14:56:23 2008 +0000 |
710 | |
9469eb4a |
711 | [perl #49472] Attributes + Unknown Error |
d82a90c1 |
712 | ... |
713 | |
714 | bisect run success |
715 | |
6acba58e |
716 | You can peek into the bisecting process with C<git bisect log> and |
717 | C<git bisect visualize>. C<git bisect reset> will get you out of bisect |
718 | mode. |
d82a90c1 |
719 | |
6acba58e |
720 | Please note that the first C<good> state must be an ancestor of the |
721 | first C<bad> state. If you want to search for the commit that I<solved> |
722 | some bug, you have to negate your test case (i.e. exit with C<1> if OK |
723 | and C<0> if not) and still mark the lower bound as C<good> and the |
724 | upper as C<bad>. The "first bad commit" has then to be understood as |
725 | the "first commit where the bug is solved". |
d82a90c1 |
726 | |
6acba58e |
727 | C<git help bisect> has much more information on how you can tweak your |
728 | binary searches. |
9d68b7ed |
729 | |
ba336be1 |
730 | =head1 Submitting a patch via GitHub |
03050721 |
731 | |
732 | GitHub is a website that makes it easy to fork and publish projects |
733 | with Git. First you should set up a GitHub account and log in. |
734 | |
735 | Perl's git repository is mirrored on GitHub at this page: |
736 | |
45b194c5 |
737 | http://github.com/mirrors/perl/tree/blead |
03050721 |
738 | |
739 | Visit the page and click the "fork" button. This clones the Perl git |
740 | repository for you and provides you with "Your Clone URL" from which |
741 | you should clone: |
742 | |
743 | % git clone git@github.com:USERNAME/perl.git perl-github |
744 | |
bdaf0bc6 |
745 | The same patch as above, using github might look like this: |
03050721 |
746 | |
747 | % cd perl-github |
edb9e29e |
748 | % git remote add upstream git://perl5.git.perl.org/perl.git |
03050721 |
749 | % git pull upstream blead |
750 | % git checkout -b orange |
751 | % perl -pi -e 's{Leon Brocard}{Orange Brocard}' AUTHORS |
dc3c3040 |
752 | % git commit -a -m 'Rename Leon Brocard to Orange Brocard' |
03050721 |
753 | % git push origin orange |
754 | |
755 | The orange branch has been pushed to GitHub, so you should now send an |
705c800c |
756 | email (see L</Submitting a patch>) with a description of your changes |
64a8e22b |
757 | and the following information: |
03050721 |
758 | |
759 | http://github.com/USERNAME/perl/tree/orange |
fb60e745 |
760 | git://github.com/USERNAME/perl.git branch orange |
03050721 |
761 | |
ba336be1 |
762 | =head1 Merging from a branch via GitHub |
c26da522 |
763 | |
764 | If someone has provided a branch via GitHub and you are a committer, |
5c9c28c6 |
765 | you should use the following in your perl-ssh directory: |
c26da522 |
766 | |
e98adcab |
767 | % git remote add avar git://github.com/avar/perl.git |
768 | % git fetch avar |
c26da522 |
769 | |
770 | Now you can see the differences between the branch and blead: |
771 | |
e98adcab |
772 | % git diff avar/orange |
c26da522 |
773 | |
774 | And you can see the commits: |
775 | |
e98adcab |
776 | % git log avar/orange |
c26da522 |
777 | |
778 | If you approve of a specific commit, you can cherry pick it: |
779 | |
e98adcab |
780 | % git cherry-pick 0c24b290ae02b2ab3304f51d5e11e85eb3659eae |
2bab0636 |
781 | |
782 | Or you could just merge the whole branch if you like it all: |
783 | |
e98adcab |
784 | % git merge avar/orange |
c26da522 |
785 | |
786 | And then push back to the repository: |
787 | |
788 | % git push |
789 | |
ce2a8773 |
790 | |
ba336be1 |
791 | =head1 Topic branches and rewriting history |
ce2a8773 |
792 | |
793 | Individual committers should create topic branches under |
333f8875 |
794 | B<yourname>/B<some_descriptive_name>. Other committers should check |
795 | with a topic branch's creator before making any change to it. |
ce2a8773 |
796 | |
b16add97 |
797 | The simplest way to create a remote topic branch that works on all |
798 | versions of git is to push the current head as a new branch on the |
799 | remote, then check it out locally: |
800 | |
801 | $ branch="$yourname/$some_descriptive_name" |
802 | $ git push origin HEAD:$branch |
803 | $ git checkout -b $branch origin/$branch |
804 | |
805 | Users of git 1.7 or newer can do it in a more obvious manner: |
806 | |
807 | $ branch="$yourname/$some_descriptive_name" |
808 | $ git checkout -b $branch |
809 | $ git push origin -u $branch |
33e5002f |
810 | |
ce2a8773 |
811 | If you are not the creator of B<yourname>/B<some_descriptive_name>, you |
812 | might sometimes find that the original author has edited the branch's |
813 | history. There are lots of good reasons for this. Sometimes, an author |
333f8875 |
814 | might simply be rebasing the branch onto a newer source point. |
815 | Sometimes, an author might have found an error in an early commit which |
816 | they wanted to fix before merging the branch to blead. |
ce2a8773 |
817 | |
333f8875 |
818 | Currently the master repository is configured to forbid |
819 | non-fast-forward merges. This means that the branches within can not |
820 | be rebased and pushed as a single step. |
ce2a8773 |
821 | |
333f8875 |
822 | The only way you will ever be allowed to rebase or modify the history |
823 | of a pushed branch is to delete it and push it as a new branch under |
824 | the same name. Please think carefully about doing this. It may be |
825 | better to sequentially rename your branches so that it is easier for |
826 | others working with you to cherry-pick their local changes onto the new |
827 | version. (XXX: needs explanation). |
ce2a8773 |
828 | |
829 | If you want to rebase a personal topic branch, you will have to delete |
2699d634 |
830 | your existing topic branch and push as a new version of it. You can do |
831 | this via the following formula (see the explanation about C<refspec>'s |
832 | in the git push documentation for details) after you have rebased your |
833 | branch: |
834 | |
835 | # first rebase |
836 | $ git checkout $user/$topic |
837 | $ git fetch |
838 | $ git rebase origin/blead |
839 | |
840 | # then "delete-and-push" |
841 | $ git push origin :$user/$topic |
842 | $ git push origin $user/$topic |
843 | |
844 | B<NOTE:> it is forbidden at the repository level to delete any of the |
333f8875 |
845 | "primary" branches. That is any branch matching |
846 | C<m!^(blead|maint|perl)!>. Any attempt to do so will result in git |
847 | producing an error like this: |
2699d634 |
848 | |
849 | $ git push origin :blead |
850 | *** It is forbidden to delete blead/maint branches in this repository |
851 | error: hooks/update exited with error code 1 |
852 | error: hook declined to update refs/heads/blead |
333f8875 |
853 | To ssh://perl5.git.perl.org/perl |
2699d634 |
854 | ! [remote rejected] blead (hook declined) |
333f8875 |
855 | error: failed to push some refs to 'ssh://perl5.git.perl.org/perl' |
2699d634 |
856 | |
333f8875 |
857 | As a matter of policy we do B<not> edit the history of the blead and |
858 | maint-* branches. If a typo (or worse) sneaks into a commit to blead or |
859 | maint-*, we'll fix it in another commit. The only types of updates |
860 | allowed on these branches are "fast-forward's", where all history is |
861 | preserved. |
2699d634 |
862 | |
333f8875 |
863 | Annotated tags in the canonical perl.git repository will never be |
864 | deleted or modified. Think long and hard about whether you want to push |
865 | a local tag to perl.git before doing so. (Pushing unannotated tags is |
2699d634 |
866 | not allowed.) |
ce2a8773 |
867 | |
ba336be1 |
868 | =head1 Committing to maintenance versions |
9d68b7ed |
869 | |
041325d6 |
870 | Maintenance versions should only be altered to add critical bug |
871 | fixes, see L<perlpolicy>. |
7f4ffa9d |
872 | |
9d68b7ed |
873 | To commit to a maintenance version of perl, you need to create a local |
874 | tracking branch: |
875 | |
876 | % git checkout --track -b maint-5.005 origin/maint-5.005 |
877 | |
0549aefb |
878 | This creates a local branch named C<maint-5.005>, which tracks the |
879 | remote branch C<origin/maint-5.005>. Then you can pull, commit, merge |
880 | and push as before. |
b0d36535 |
881 | |
f755e97d |
882 | You can also cherry-pick commits from blead and another branch, by |
0549aefb |
883 | using the C<git cherry-pick> command. It is recommended to use the |
884 | B<-x> option to C<git cherry-pick> in order to record the SHA1 of the |
885 | original commit in the new commit message. |
f755e97d |
886 | |
ba336be1 |
887 | =head1 Grafts |
e8589bfa |
888 | |
889 | The perl history contains one mistake which was not caught in the |
ac036724 |
890 | conversion: a merge was recorded in the history between blead and |
333f8875 |
891 | maint-5.10 where no merge actually occurred. Due to the nature of git, |
892 | this is now impossible to fix in the public repository. You can remove |
893 | this mis-merge locally by adding the following line to your |
e8589bfa |
894 | C<.git/info/grafts> file: |
895 | |
896 | 296f12bbbbaa06de9be9d09d3dcf8f4528898a49 434946e0cb7a32589ed92d18008aaa1d88515930 |
897 | |
898 | It is particularly important to have this graft line if any bisecting |
899 | is done in the area of the "merge" in question. |
900 | |
041325d6 |
901 | =head1 SEE ALSO |
bdaf0bc6 |
902 | |
041325d6 |
903 | =over |
bdaf0bc6 |
904 | |
705c800c |
905 | =item * |
041325d6 |
906 | |
705c800c |
907 | The git documentation, accessible via the C<git help> command |
908 | |
909 | =item * |
910 | |
911 | L<perlpolicy> - Perl core development policy |
041325d6 |
912 | |
913 | =back |
f755e97d |
914 | |
041325d6 |
915 | =cut |