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1 | =for comment |
2 | Consistent formatting of this file is achieved with: |
3 | perl ./Porting/podtidy pod/perlrepository.pod |
4 | |
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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 |
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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. |
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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). |
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22 | |
23 | =head1 GETTING ACCESS TO THE REPOSITORY |
24 | |
25 | =head2 READ ACCESS VIA THE WEB |
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: |
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30 | |
31 | http://perl5.git.perl.org/perl.git |
32 | |
dc3c3040 |
33 | A mirror of the repository is found at: |
34 | |
35 | http://github.com/github/perl |
36 | |
d7dd28b6 |
37 | =head2 READ ACCESS VIA GIT |
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 | |
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42 | git clone git://perl5.git.perl.org/perl.git perl-git |
d7dd28b6 |
43 | |
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44 | This clones the repository and makes a local copy in the F<perl-git> |
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45 | directory. |
46 | |
47 | If your local network does not allow you to use port 9418, then you can |
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48 | fetch a copy of the repository over HTTP (this is slower): |
d7dd28b6 |
49 | |
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50 | git clone http://perl5.git.perl.org/perl.git perl-http |
d7dd28b6 |
51 | |
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52 | This clones the repository and makes a local copy in the F<perl-http> |
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53 | directory. |
54 | |
55 | =head2 WRITE ACCESS TO THE REPOSITORY |
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: |
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59 | |
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60 | git clone ssh://perl5.git.perl.org/gitroot/perl.git perl-ssh |
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61 | |
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62 | This clones the repository and makes a local copy in the F<perl-ssh> |
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63 | directory. |
64 | |
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65 | If you cloned using the git protocol, which is faster than ssh, then |
66 | you will need to modify your config in order to enable pushing. Edit |
67 | F<.git/config> where you will see something like: |
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68 | |
69 | [remote "origin"] |
70 | url = git://perl5.git.perl.org/perl.git |
71 | |
72 | change that to something like this: |
73 | |
74 | [remote "origin"] |
75 | url = ssh://perl5.git.perl.org/gitroot/perl.git |
76 | |
dc3c3040 |
77 | NOTE: there are symlinks set up so that the /gitroot is optional and |
78 | since SSH is the default protocol you can actually shorten the "url" to |
79 | C<perl5.git.perl.org:/perl.git>. |
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80 | |
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81 | You can also set up your user name and e-mail address. For example |
82 | |
83 | % git config user.name "Leon Brocard" |
84 | % git config user.email acme@astray.com |
85 | |
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86 | It is also possible to keep C<origin> as a git remote, and add a new |
87 | remote for ssh access: |
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88 | |
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89 | % git remote add camel perl5.git.perl.org:/perl.git |
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90 | |
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91 | This allows you to update your local repository by pulling from |
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92 | C<origin>, which is faster and doesn't require you to authenticate, and |
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93 | to push your changes back with the C<camel> remote: |
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94 | |
95 | % git fetch camel |
96 | % git push camel |
97 | |
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98 | The C<fetch> command just updates the C<camel> refs, as the objects |
99 | themselves should have been fetched when pulling from C<origin>. |
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100 | |
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101 | The committers have access to 2 servers that serve perl5.git.perl.org. |
102 | One is camel.booking.com, which is the 'master' repository. The |
103 | perl5.git.perl.org IP address also lives on this machine. The second |
104 | one is dromedary.booking.com, which can be used for general testing and |
105 | development. Dromedary syncs the git tree from camel every few minutes, |
106 | you should not push there. Both machines also have a full CPAN mirror. |
107 | To share files with the general public, dromedary serves your |
108 | ~/public_html/ as http://users.perl5.git.perl.org/~yourlogin/ |
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109 | |
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110 | =head1 OVERVIEW OF THE REPOSITORY |
111 | |
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112 | Once you have changed into the repository directory, you can inspect |
113 | it. |
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114 | |
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115 | After a clone the repository will contain a single local branch, which |
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116 | will be the current branch as well, as indicated by the asterisk. |
39219fd3 |
117 | |
118 | % git branch |
119 | * blead |
120 | |
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121 | Using the -a switch to C<branch> will also show the remote tracking |
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122 | branches in the repository: |
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123 | |
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124 | % git branch -a |
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125 | * blead |
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126 | origin/HEAD |
127 | origin/blead |
128 | ... |
129 | |
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130 | The branches that begin with "origin" correspond to the "git remote" |
131 | that you cloned from (which is named "origin"). Each branch on the |
132 | remote will be exactly tracked by theses branches. You should NEVER do |
133 | work on these remote tracking branches. You only ever do work in a |
134 | local branch. Local branches can be configured to automerge (on pull) |
135 | from a designated remote tracking branch. This is the case with the |
136 | default branch C<blead> which will be configured to merge from the |
137 | remote tracking branch C<origin/blead>. |
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138 | |
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139 | You can see recent commits: |
140 | |
c2cf2042 |
141 | % git log |
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142 | |
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143 | And pull new changes from the repository, and update your local |
144 | repository (must be clean first) |
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145 | |
146 | % git pull |
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147 | |
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148 | Assuming we are on the branch C<blead> immediately after a pull, this |
149 | command would be more or less equivalent to: |
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150 | |
151 | % git fetch |
152 | % git merge origin/blead |
153 | |
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154 | In fact if you want to update your local repository without touching |
155 | your working directory you do: |
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156 | |
157 | % git fetch |
158 | |
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159 | And if you want to update your remote-tracking branches for all defined |
160 | remotes simultaneously you can do |
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161 | |
162 | % git remote update |
163 | |
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164 | Neither of these last two commands will update your working directory, |
165 | however both will update the remote-tracking branches in your |
166 | repository. |
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167 | |
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168 | To switch to another branch: |
169 | |
170 | % git checkout origin/maint-5.8-dor |
171 | |
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172 | To make a local branch of a remote branch: |
173 | |
174 | % git checkout -b maint-5.10 origin/maint-5.10 |
175 | |
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176 | To switch back to blead: |
177 | |
178 | % git checkout blead |
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179 | |
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180 | =head2 FINDING OUT YOUR STATUS |
181 | |
182 | The most common git command you will use will probably be |
183 | |
184 | % git status |
185 | |
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186 | This command will produce as output a description of the current state |
187 | of the repository, including modified files and unignored untracked |
188 | files, and in addition it will show things like what files have been |
189 | staged for the next commit, and usually some useful information about |
190 | how to change things. For instance the following: |
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191 | |
192 | $ git status |
193 | # On branch blead |
194 | # Your branch is ahead of 'origin/blead' by 1 commit. |
195 | # |
196 | # Changes to be committed: |
197 | # (use "git reset HEAD <file>..." to unstage) |
198 | # |
199 | # modified: pod/perlrepository.pod |
200 | # |
201 | # Changed but not updated: |
202 | # (use "git add <file>..." to update what will be committed) |
203 | # |
204 | # modified: pod/perlrepository.pod |
205 | # |
206 | # Untracked files: |
207 | # (use "git add <file>..." to include in what will be committed) |
208 | # |
209 | # deliberate.untracked |
210 | |
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211 | This shows that there were changes to this document staged for commit, |
212 | and that there were further changes in the working directory not yet |
213 | staged. It also shows that there was an untracked file in the working |
214 | directory, and as you can see shows how to change all of this. It also |
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215 | shows that there is one commit on the working branch C<blead> which has |
216 | not been pushed to the C<origin> remote yet. B<NOTE>: that this output |
217 | is also what you see as a template if you do not provide a message to |
218 | C<git commit>. |
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219 | |
220 | Assuming we commit all the mentioned changes above: |
221 | |
222 | % git commit -a -m'explain git status and stuff about remotes' |
223 | Created commit daf8e63: explain git status and stuff about remotes |
224 | 1 files changed, 83 insertions(+), 3 deletions(-) |
225 | |
226 | We can re-run git status and see something like this: |
227 | |
228 | % git status |
229 | # On branch blead |
230 | # Your branch is ahead of 'origin/blead' by 2 commits. |
231 | # |
232 | # Untracked files: |
233 | # (use "git add <file>..." to include in what will be committed) |
234 | # |
235 | # deliberate.untracked |
236 | nothing added to commit but untracked files present (use "git add" to track) |
237 | |
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238 | |
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239 | When in doubt, before you do anything else, check your status and read |
240 | it carefully, many questions are answered directly by the git status |
241 | output. |
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242 | |
c2cf2042 |
243 | =head1 SUBMITTING A PATCH |
244 | |
245 | If you have a patch in mind for Perl, you should first get a copy of |
246 | the repository: |
247 | |
248 | % git clone git://perl5.git.perl.org/perl.git perl-git |
249 | |
250 | Then change into the directory: |
251 | |
252 | % cd perl-git |
253 | |
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254 | Alternatively, if you already have a Perl repository, you should ensure |
255 | that you're on the I<blead> branch, and your repository is up to date: |
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256 | |
257 | % git checkout blead |
258 | % git pull |
259 | |
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260 | It's preferable to patch against the latest blead version, since this |
261 | is where new development occurs for all changes other than critical bug |
262 | fixes. Critical bug fix patches should be made against the relevant |
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263 | maint branches, or should be submitted with a note indicating all the |
264 | branches where the fix should be applied. |
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265 | |
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266 | Now that we have everything up to date, we need to create a temporary |
267 | new branch for these changes and switch into it: |
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268 | |
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269 | % git checkout -b orange |
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270 | |
a9b05323 |
271 | which is the short form of |
272 | |
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273 | % git branch orange |
274 | % git checkout orange |
275 | |
c2cf2042 |
276 | Then make your changes. For example, if Leon Brocard changes his name |
277 | to Orange Brocard, we should change his name in the AUTHORS file: |
278 | |
279 | % perl -pi -e 's{Leon Brocard}{Orange Brocard}' AUTHORS |
280 | |
281 | You can see what files are changed: |
282 | |
283 | % git status |
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284 | # On branch orange |
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285 | # Changes to be committed: |
286 | # (use "git reset HEAD <file>..." to unstage) |
287 | # |
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288 | # modified: AUTHORS |
c2cf2042 |
289 | # |
290 | |
c2cf2042 |
291 | And you can see the changes: |
292 | |
293 | % git diff |
294 | diff --git a/AUTHORS b/AUTHORS |
295 | index 293dd70..722c93e 100644 |
296 | --- a/AUTHORS |
297 | +++ b/AUTHORS |
7df2e4bc |
298 | @@ -541,7 +541,7 @@ Lars Hecking <lhecking@nmrc.ucc.ie> |
c2cf2042 |
299 | Laszlo Molnar <laszlo.molnar@eth.ericsson.se> |
300 | Leif Huhn <leif@hale.dkstat.com> |
301 | Len Johnson <lenjay@ibm.net> |
302 | -Leon Brocard <acme@astray.com> |
303 | +Orange Brocard <acme@astray.com> |
304 | Les Peters <lpeters@aol.net> |
305 | Lesley Binks <lesley.binks@gmail.com> |
306 | Lincoln D. Stein <lstein@cshl.org> |
307 | |
308 | Now commit your change locally: |
309 | |
dc3c3040 |
310 | % git commit -a -m 'Rename Leon Brocard to Orange Brocard' |
c2cf2042 |
311 | Created commit 6196c1d: Rename Leon Brocard to Orange Brocard |
312 | 1 files changed, 1 insertions(+), 1 deletions(-) |
313 | |
dc3c3040 |
314 | You can examine your last commit with: |
315 | |
316 | % git show HEAD |
317 | |
318 | and if you are not happy with either the description or the patch |
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319 | itself you can fix it up by editing the files once more and then issue: |
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320 | |
321 | % git commit -a --amend |
322 | |
c2cf2042 |
323 | Now you should create a patch file for all your local changes: |
324 | |
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325 | % git format-patch origin |
c2cf2042 |
326 | 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch |
327 | |
328 | You should now send an email to perl5-porters@perl.org with a |
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329 | description of your changes, and include this patch file as an |
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330 | attachment. (See the next section for how to configure and use |
331 | git to send these emails for you.) |
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332 | |
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333 | If you want to delete your temporary branch, you may do so with: |
334 | |
335 | % git checkout blead |
336 | % git branch -d orange |
337 | error: The branch 'orange' is not an ancestor of your current HEAD. |
338 | If you are sure you want to delete it, run 'git branch -D orange'. |
339 | % git branch -D orange |
340 | Deleted branch orange. |
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341 | |
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342 | =head2 Using git to send patch emails |
343 | |
344 | In your ~/git/perl repository, set the destination email to the perl5-porters |
345 | mailing list. |
346 | |
347 | $ git config sendemail.to perl5-porters@perl.org |
348 | |
349 | Then you can use git directly to send your patch emails: |
350 | |
351 | $ git send-email 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch |
352 | |
353 | You may need to set some configuration variables for your particular email |
354 | service provider. For example, to set your global git config to send email via |
355 | a gmail account: |
356 | |
357 | $ git config --global sendemail.smtpserver smtp.gmail.com |
358 | $ git config --global sendemail.smtpssl 1 |
359 | $ git config --global sendemail.smtpuser YOURUSERNAME@gmail.com |
360 | |
361 | With this configuration, you will be prompted for your gmail password when you |
362 | run 'git send-email'. You can also configure C<sendemail.smtppass> with your |
363 | password if you don't care about having your password in the .gitconfig file. |
364 | |
a44f43ac |
365 | =head2 A note on derived files |
366 | |
367 | Be aware that many files in the distribution are derivative--avoid |
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368 | patching them, because git won't see the changes to them, and the build |
369 | process will overwrite them. Patch the originals instead. Most |
370 | utilities (like perldoc) are in this category, i.e. patch |
371 | utils/perldoc.PL rather than utils/perldoc. Similarly, don't create |
372 | patches for files under $src_root/ext from their copies found in |
373 | $install_root/lib. If you are unsure about the proper location of a |
374 | file that may have gotten copied while building the source |
375 | distribution, consult the C<MANIFEST>. |
a44f43ac |
376 | |
6e2cec71 |
377 | =for XXX |
a44f43ac |
378 | |
6e2cec71 |
379 | What should we recommend about binary files now? Do we need anything? |
a44f43ac |
380 | |
381 | =head2 Getting your patch accepted |
382 | |
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383 | The first thing you should include with your patch is a description of |
384 | the problem that the patch corrects. If it is a code patch (rather |
385 | than a documentation patch) you should also include a small test case |
386 | that illustrates the bug (a patch to an existing test file is |
387 | preferred). |
a44f43ac |
388 | |
389 | If you are submitting a code patch there are several other things that |
390 | you need to do. |
391 | |
392 | =over 4 |
393 | |
394 | =item Comments, Comments, Comments |
395 | |
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396 | Be sure to adequately comment your code. While commenting every line |
397 | is unnecessary, anything that takes advantage of side effects of |
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398 | operators, that creates changes that will be felt outside of the |
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399 | function being patched, or that others may find confusing should be |
400 | documented. If you are going to err, it is better to err on the side |
401 | of adding too many comments than too few. |
a44f43ac |
402 | |
403 | =item Style |
404 | |
0549aefb |
405 | In general, please follow the particular style of the code you are |
406 | patching. |
a44f43ac |
407 | |
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408 | In particular, follow these general guidelines for patching Perl |
409 | sources: |
a44f43ac |
410 | |
411 | 8-wide tabs (no exceptions!) |
412 | 4-wide indents for code, 2-wide indents for nested CPP #defines |
413 | try hard not to exceed 79-columns |
414 | ANSI C prototypes |
415 | uncuddled elses and "K&R" style for indenting control constructs |
416 | no C++ style (//) comments |
417 | mark places that need to be revisited with XXX (and revisit often!) |
418 | opening brace lines up with "if" when conditional spans multiple |
419 | lines; should be at end-of-line otherwise |
420 | in function definitions, name starts in column 0 (return value is on |
421 | previous line) |
422 | single space after keywords that are followed by parens, no space |
423 | between function name and following paren |
424 | avoid assignments in conditionals, but if they're unavoidable, use |
425 | extra paren, e.g. "if (a && (b = c)) ..." |
426 | "return foo;" rather than "return(foo);" |
427 | "if (!foo) ..." rather than "if (foo == FALSE) ..." etc. |
428 | |
429 | =item Testsuite |
430 | |
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431 | When submitting a patch you should make every effort to also include an |
2699d634 |
432 | addition to perl's regression tests to properly exercise your patch. |
0549aefb |
433 | Your testsuite additions should generally follow these guidelines |
434 | (courtesy of Gurusamy Sarathy <gsar@activestate.com>): |
a44f43ac |
435 | |
436 | Know what you're testing. Read the docs, and the source. |
437 | Tend to fail, not succeed. |
438 | Interpret results strictly. |
439 | Use unrelated features (this will flush out bizarre interactions). |
440 | Use non-standard idioms (otherwise you are not testing TIMTOWTDI). |
441 | Avoid using hardcoded test numbers whenever possible (the |
442 | EXPECTED/GOT found in t/op/tie.t is much more maintainable, |
443 | and gives better failure reports). |
444 | Give meaningful error messages when a test fails. |
445 | Avoid using qx// and system() unless you are testing for them. If you |
446 | do use them, make sure that you cover _all_ perl platforms. |
447 | Unlink any temporary files you create. |
448 | Promote unforeseen warnings to errors with $SIG{__WARN__}. |
449 | Be sure to use the libraries and modules shipped with the version |
450 | being tested, not those that were already installed. |
451 | Add comments to the code explaining what you are testing for. |
452 | Make updating the '1..42' string unnecessary. Or make sure that |
453 | you update it. |
454 | Test _all_ behaviors of a given operator, library, or function: |
455 | - All optional arguments |
456 | - Return values in various contexts (boolean, scalar, list, lvalue) |
457 | - Use both global and lexical variables |
458 | - Don't forget the exceptional, pathological cases. |
459 | |
460 | =back |
461 | |
7df2e4bc |
462 | =head1 ACCEPTING A PATCH |
463 | |
464 | If you have received a patch file generated using the above section, |
465 | you should try out the patch. |
466 | |
467 | First we need to create a temporary new branch for these changes and |
468 | switch into it: |
469 | |
a9b05323 |
470 | % git checkout -b experimental |
7df2e4bc |
471 | |
6acba58e |
472 | Patches that were formatted by C<git format-patch> are applied with |
473 | C<git am>: |
7df2e4bc |
474 | |
2af192ee |
475 | % git am 0001-Rename-Leon-Brocard-to-Orange-Brocard.patch |
7df2e4bc |
476 | Applying Rename Leon Brocard to Orange Brocard |
477 | |
6acba58e |
478 | If just a raw diff is provided, it is also possible use this two-step |
479 | process: |
09645c26 |
480 | |
481 | % git apply bugfix.diff |
dc3c3040 |
482 | % git commit -a -m "Some fixing" --author="That Guy <that.guy@internets.com>" |
09645c26 |
483 | |
7df2e4bc |
484 | Now we can inspect the change: |
485 | |
dc3c3040 |
486 | % git show HEAD |
7df2e4bc |
487 | commit b1b3dab48344cff6de4087efca3dbd63548ab5e2 |
488 | Author: Leon Brocard <acme@astray.com> |
489 | Date: Fri Dec 19 17:02:59 2008 +0000 |
490 | |
491 | Rename Leon Brocard to Orange Brocard |
7df2e4bc |
492 | |
7df2e4bc |
493 | diff --git a/AUTHORS b/AUTHORS |
494 | index 293dd70..722c93e 100644 |
495 | --- a/AUTHORS |
496 | +++ b/AUTHORS |
497 | @@ -541,7 +541,7 @@ Lars Hecking <lhecking@nmrc.ucc.ie> |
498 | Laszlo Molnar <laszlo.molnar@eth.ericsson.se> |
499 | Leif Huhn <leif@hale.dkstat.com> |
500 | Len Johnson <lenjay@ibm.net> |
501 | -Leon Brocard <acme@astray.com> |
502 | +Orange Brocard <acme@astray.com> |
503 | Les Peters <lpeters@aol.net> |
504 | Lesley Binks <lesley.binks@gmail.com> |
505 | Lincoln D. Stein <lstein@cshl.org> |
506 | |
507 | If you are a committer to Perl and you think the patch is good, you can |
75fb7651 |
508 | then merge it into blead then push it out to the main repository: |
7df2e4bc |
509 | |
510 | % git checkout blead |
d9847473 |
511 | % git merge experimental |
75fb7651 |
512 | % git push |
7df2e4bc |
513 | |
514 | If you want to delete your temporary branch, you may do so with: |
515 | |
516 | % git checkout blead |
517 | % git branch -d experimental |
518 | error: The branch 'experimental' is not an ancestor of your current HEAD. |
519 | If you are sure you want to delete it, run 'git branch -D experimental'. |
520 | % git branch -D experimental |
521 | Deleted branch experimental. |
b0d36535 |
522 | |
523 | =head1 CLEANING A WORKING DIRECTORY |
524 | |
6acba58e |
525 | The command C<git clean> can with varying arguments be used as a |
dc3c3040 |
526 | replacement for C<make clean>. |
b0d36535 |
527 | |
528 | To reset your working directory to a pristine condition you can do: |
529 | |
530 | git clean -dxf |
531 | |
532 | However, be aware this will delete ALL untracked content. You can use |
533 | |
534 | git clean -Xf |
535 | |
6acba58e |
536 | to remove all ignored untracked files, such as build and test |
537 | byproduct, but leave any manually created files alone. |
b0d36535 |
538 | |
0549aefb |
539 | If you only want to cancel some uncommitted edits, you can use C<git |
c26da522 |
540 | checkout> and give it a list of files to be reverted, or C<git checkout |
541 | -f> to revert them all. |
f755e97d |
542 | |
543 | If you want to cancel one or several commits, you can use C<git reset>. |
544 | |
d82a90c1 |
545 | =head1 BISECTING |
546 | |
6acba58e |
547 | C<git> provides a built-in way to determine, with a binary search in |
548 | the history, which commit should be blamed for introducing a given bug. |
d82a90c1 |
549 | |
6acba58e |
550 | Suppose that we have a script F<~/testcase.pl> that exits with C<0> |
551 | when some behaviour is correct, and with C<1> when it's faulty. We need |
552 | an helper script that automates building C<perl> and running the |
553 | testcase: |
d82a90c1 |
554 | |
555 | % cat ~/run |
556 | #!/bin/sh |
557 | git clean -dxf |
558 | # If you can use ccache, add -Dcc=ccache\ gcc -Dld=gcc to the Configure line |
c0d1ef72 |
559 | sh Configure -des -Dusedevel -Doptimize="-g" |
560 | test -f config.sh || exit 125 |
561 | # Correct makefile for newer GNU gcc |
562 | perl -ni -we 'print unless /<(?:built-in|command)/' makefile x2p/makefile |
563 | # if you just need miniperl, replace test_prep with miniperl |
564 | make -j4 test_prep |
68814ba4 |
565 | [ -x ./perl ] || exit 125 |
d82a90c1 |
566 | ./perl -Ilib ~/testcase.pl |
c0d1ef72 |
567 | ret=$? |
7930c68b |
568 | [ $ret -gt 127 ] && ret=127 |
c0d1ef72 |
569 | git clean -dxf |
570 | exit $ret |
d82a90c1 |
571 | |
6acba58e |
572 | This script may return C<125> to indicate that the corresponding commit |
573 | should be skipped. Otherwise, it returns the status of |
574 | F<~/testcase.pl>. |
d82a90c1 |
575 | |
576 | We first enter in bisect mode with: |
577 | |
578 | % git bisect start |
579 | |
6acba58e |
580 | For example, if the bug is present on C<HEAD> but wasn't in 5.10.0, |
581 | C<git> will learn about this when you enter: |
d82a90c1 |
582 | |
583 | % git bisect bad |
584 | % git bisect good perl-5.10.0 |
585 | Bisecting: 853 revisions left to test after this |
586 | |
6acba58e |
587 | This results in checking out the median commit between C<HEAD> and |
588 | C<perl-5.10.0>. We can then run the bisecting process with: |
d82a90c1 |
589 | |
590 | % git bisect run ~/run |
591 | |
592 | When the first bad commit is isolated, C<git bisect> will tell you so: |
593 | |
594 | ca4cfd28534303b82a216cfe83a1c80cbc3b9dc5 is first bad commit |
595 | commit ca4cfd28534303b82a216cfe83a1c80cbc3b9dc5 |
596 | Author: Dave Mitchell <davem@fdisolutions.com> |
597 | Date: Sat Feb 9 14:56:23 2008 +0000 |
598 | |
9469eb4a |
599 | [perl #49472] Attributes + Unknown Error |
d82a90c1 |
600 | ... |
601 | |
602 | bisect run success |
603 | |
6acba58e |
604 | You can peek into the bisecting process with C<git bisect log> and |
605 | C<git bisect visualize>. C<git bisect reset> will get you out of bisect |
606 | mode. |
d82a90c1 |
607 | |
6acba58e |
608 | Please note that the first C<good> state must be an ancestor of the |
609 | first C<bad> state. If you want to search for the commit that I<solved> |
610 | some bug, you have to negate your test case (i.e. exit with C<1> if OK |
611 | and C<0> if not) and still mark the lower bound as C<good> and the |
612 | upper as C<bad>. The "first bad commit" has then to be understood as |
613 | the "first commit where the bug is solved". |
d82a90c1 |
614 | |
6acba58e |
615 | C<git help bisect> has much more information on how you can tweak your |
616 | binary searches. |
9d68b7ed |
617 | |
03050721 |
618 | =head1 SUBMITTING A PATCH VIA GITHUB |
619 | |
620 | GitHub is a website that makes it easy to fork and publish projects |
621 | with Git. First you should set up a GitHub account and log in. |
622 | |
623 | Perl's git repository is mirrored on GitHub at this page: |
624 | |
625 | http://github.com/github/perl/tree/blead |
626 | |
627 | Visit the page and click the "fork" button. This clones the Perl git |
628 | repository for you and provides you with "Your Clone URL" from which |
629 | you should clone: |
630 | |
631 | % git clone git@github.com:USERNAME/perl.git perl-github |
632 | |
633 | We shall make the same patch as above, creating a new branch: |
634 | |
635 | % cd perl-github |
636 | % git remote add upstream git://github.com/github/perl.git |
637 | % git pull upstream blead |
638 | % git checkout -b orange |
639 | % perl -pi -e 's{Leon Brocard}{Orange Brocard}' AUTHORS |
dc3c3040 |
640 | % git commit -a -m 'Rename Leon Brocard to Orange Brocard' |
03050721 |
641 | % git push origin orange |
642 | |
643 | The orange branch has been pushed to GitHub, so you should now send an |
644 | email to perl5-porters@perl.org with a description of your changes and |
645 | the following information: |
646 | |
647 | http://github.com/USERNAME/perl/tree/orange |
648 | git@github.com:USERNAME/perl.git branch orange |
649 | |
c26da522 |
650 | =head1 MERGING FROM A BRANCH VIA GITHUB |
651 | |
652 | If someone has provided a branch via GitHub and you are a committer, |
5c9c28c6 |
653 | you should use the following in your perl-ssh directory: |
c26da522 |
654 | |
655 | % git remote add dandv git://github.com/dandv/perl.git |
656 | % git fetch |
657 | |
658 | Now you can see the differences between the branch and blead: |
659 | |
660 | % git diff dandv/blead |
661 | |
662 | And you can see the commits: |
663 | |
664 | % git log dandv/blead |
665 | |
666 | If you approve of a specific commit, you can cherry pick it: |
667 | |
2bab0636 |
668 | % git cherry-pick 3adac458cb1c1d41af47fc66e67b49c8dec2323f |
669 | |
670 | Or you could just merge the whole branch if you like it all: |
671 | |
672 | % git merge dandv/blead |
c26da522 |
673 | |
674 | And then push back to the repository: |
675 | |
676 | % git push |
677 | |
ce2a8773 |
678 | |
679 | =head1 TOPIC BRANCHES AND REWRITING HISTORY |
680 | |
681 | Individual committers should create topic branches under |
682 | B<yourname>/B<some_descriptive_name>. Other committers should check with |
683 | a topic branch's creator before making any change to it. |
684 | |
685 | If you are not the creator of B<yourname>/B<some_descriptive_name>, you |
686 | might sometimes find that the original author has edited the branch's |
687 | history. There are lots of good reasons for this. Sometimes, an author |
688 | might simply be rebasing the branch onto a newer source point. Sometimes, |
689 | an author might have found an error in an early commit which they wanted |
690 | to fix before merging the branch to blead. |
691 | |
692 | Currently the master repository is configured to forbid non-fast-forward |
693 | merges. This means that the branches within can not be rebased and |
694 | pushed as a single step. |
695 | |
2699d634 |
696 | The only way you will ever be allowed to rebase or modify the history of |
697 | a pushed branch is to delete it and push it as a new branch under the same |
698 | name. Please think carefully about doing this. It may be better to sequentially |
699 | rename your branches so that it is easier for others working with you to |
700 | cherry-pick their local changes onto the new version. (XXX: needs |
701 | explanation). |
ce2a8773 |
702 | |
703 | If you want to rebase a personal topic branch, you will have to delete |
2699d634 |
704 | your existing topic branch and push as a new version of it. You can do |
705 | this via the following formula (see the explanation about C<refspec>'s |
706 | in the git push documentation for details) after you have rebased your |
707 | branch: |
708 | |
709 | # first rebase |
710 | $ git checkout $user/$topic |
711 | $ git fetch |
712 | $ git rebase origin/blead |
713 | |
714 | # then "delete-and-push" |
715 | $ git push origin :$user/$topic |
716 | $ git push origin $user/$topic |
717 | |
718 | B<NOTE:> it is forbidden at the repository level to delete any of the |
719 | "primary" branches. That is any branch matching C<m!^(blead|maint|perl)!>. |
720 | Any attempt to do so will result in git producing an error like this: |
721 | |
722 | $ git push origin :blead |
723 | *** It is forbidden to delete blead/maint branches in this repository |
724 | error: hooks/update exited with error code 1 |
725 | error: hook declined to update refs/heads/blead |
726 | To ssh://camel.booking.com/perl |
727 | ! [remote rejected] blead (hook declined) |
728 | error: failed to push some refs to 'ssh://camel.booking.com/perl' |
729 | |
730 | As a matter of policy we do B<not> edit the history of the blead and maint-* |
731 | branches. If a typo (or worse) sneaks into a commit to blead or maint-*, we'll |
732 | fix it in another commit. The only types of updates allowed on these |
733 | branches are "fast-forward's", where all history is preserved. |
734 | |
735 | Annotated tags in the canonical perl.git repository will never be deleted |
736 | or modified. Think long and hard about whether you want to push a local |
737 | tag to perl.git before doing so. (Pushing unannotated tags is |
738 | not allowed.) |
ce2a8773 |
739 | |
9469eb4a |
740 | =head1 COMMITTING TO MAINTENANCE VERSIONS |
9d68b7ed |
741 | |
7f4ffa9d |
742 | Maintenance versions should only be altered to add critical bug fixes. |
743 | |
9d68b7ed |
744 | To commit to a maintenance version of perl, you need to create a local |
745 | tracking branch: |
746 | |
747 | % git checkout --track -b maint-5.005 origin/maint-5.005 |
748 | |
0549aefb |
749 | This creates a local branch named C<maint-5.005>, which tracks the |
750 | remote branch C<origin/maint-5.005>. Then you can pull, commit, merge |
751 | and push as before. |
b0d36535 |
752 | |
f755e97d |
753 | You can also cherry-pick commits from blead and another branch, by |
0549aefb |
754 | using the C<git cherry-pick> command. It is recommended to use the |
755 | B<-x> option to C<git cherry-pick> in order to record the SHA1 of the |
756 | original commit in the new commit message. |
f755e97d |
757 | |
e8589bfa |
758 | =head1 GRAFTS |
759 | |
760 | The perl history contains one mistake which was not caught in the |
761 | conversion -- a merge was recorded in the history between blead and |
762 | maint-5.10 where no merge actually occurred. Due to the nature of |
763 | git, this is now impossible to fix in the public repository. You can |
764 | remove this mis-merge locally by adding the following line to your |
765 | C<.git/info/grafts> file: |
766 | |
767 | 296f12bbbbaa06de9be9d09d3dcf8f4528898a49 434946e0cb7a32589ed92d18008aaa1d88515930 |
768 | |
769 | It is particularly important to have this graft line if any bisecting |
770 | is done in the area of the "merge" in question. |
771 | |
f755e97d |
772 | =head1 SEE ALSO |
773 | |
774 | The git documentation, accessible via C<git help command>. |
0549aefb |
775 | |