Merge branch 'maint'
[git/git.git] / Documentation / SubmittingPatches
1 Checklist (and a short version for the impatient):
2
3 Commits:
4
5 - make commits of logical units
6 - check for unnecessary whitespace with "git diff --check"
7 before committing
8 - do not check in commented out code or unneeded files
9 - provide a meaningful commit message
10 - the first line of the commit message should be a short
11 description and should skip the full stop
12 - if you want your work included in git.git, add a
13 "Signed-off-by: Your Name <your@email.com>" line to the
14 commit message (or just use the option "-s" when
15 committing) to confirm that you agree to the Developer's
16 Certificate of Origin
17 - make sure that you have tests for the bug you are fixing
18 - make sure that the test suite passes after your commit
19
20 Patch:
21
22 - use "git format-patch -M" to create the patch
23 - send your patch to <git@vger.kernel.org>. If you use
24 git-send-email(1), please test it first by sending
25 email to yourself.
26 - do not PGP sign your patch
27 - do not attach your patch, but read in the mail
28 body, unless you cannot teach your mailer to
29 leave the formatting of the patch alone.
30 - be careful doing cut & paste into your mailer, not to
31 corrupt whitespaces.
32 - provide additional information (which is unsuitable for
33 the commit message) between the "---" and the diffstat
34 - send the patch to the list _and_ the maintainer
35 - if you change, add, or remove a command line option or
36 make some other user interface change, the associated
37 documentation should be updated as well.
38 - if your name is not writable in ASCII, make sure that
39 you send off a message in the correct encoding.
40
41 Long version:
42
43 I started reading over the SubmittingPatches document for Linux
44 kernel, primarily because I wanted to have a document similar to
45 it for the core GIT to make sure people understand what they are
46 doing when they write "Signed-off-by" line.
47
48 But the patch submission requirements are a lot more relaxed
49 here on the technical/contents front, because the core GIT is
50 thousand times smaller ;-). So here is only the relevant bits.
51
52
53 (1) Make separate commits for logically separate changes.
54
55 Unless your patch is really trivial, you should not be sending
56 out a patch that was generated between your working tree and
57 your commit head. Instead, always make a commit with complete
58 commit message and generate a series of patches from your
59 repository. It is a good discipline.
60
61 Describe the technical detail of the change(s).
62
63 If your description starts to get too long, that's a sign that you
64 probably need to split up your commit to finer grained pieces.
65
66 Oh, another thing. I am picky about whitespaces. Make sure your
67 changes do not trigger errors with the sample pre-commit hook shipped
68 in templates/hooks--pre-commit. To help ensure this does not happen,
69 run git diff --check on your changes before you commit.
70
71
72 (1a) Try to be nice to older C compilers
73
74 We try to support wide range of C compilers to compile
75 git with. That means that you should not use C99 initializers, even
76 if a lot of compilers grok it.
77
78 Also, variables have to be declared at the beginning of the block
79 (you can check this with gcc, using the -Wdeclaration-after-statement
80 option).
81
82 Another thing: NULL pointers shall be written as NULL, not as 0.
83
84
85 (2) Generate your patch using git tools out of your commits.
86
87 git based diff tools (git, Cogito, and StGIT included) generate
88 unidiff which is the preferred format.
89
90 You do not have to be afraid to use -M option to "git diff" or
91 "git format-patch", if your patch involves file renames. The
92 receiving end can handle them just fine.
93
94 Please make sure your patch does not include any extra files
95 which do not belong in a patch submission. Make sure to review
96 your patch after generating it, to ensure accuracy. Before
97 sending out, please make sure it cleanly applies to the "master"
98 branch head. If you are preparing a work based on "next" branch,
99 that is fine, but please mark it as such.
100
101
102 (3) Sending your patches.
103
104 People on the git mailing list need to be able to read and
105 comment on the changes you are submitting. It is important for
106 a developer to be able to "quote" your changes, using standard
107 e-mail tools, so that they may comment on specific portions of
108 your code. For this reason, all patches should be submitted
109 "inline". WARNING: Be wary of your MUAs word-wrap
110 corrupting your patch. Do not cut-n-paste your patch; you can
111 lose tabs that way if you are not careful.
112
113 It is a common convention to prefix your subject line with
114 [PATCH]. This lets people easily distinguish patches from other
115 e-mail discussions.
116
117 "git format-patch" command follows the best current practice to
118 format the body of an e-mail message. At the beginning of the
119 patch should come your commit message, ending with the
120 Signed-off-by: lines, and a line that consists of three dashes,
121 followed by the diffstat information and the patch itself. If
122 you are forwarding a patch from somebody else, optionally, at
123 the beginning of the e-mail message just before the commit
124 message starts, you can put a "From: " line to name that person.
125
126 You often want to add additional explanation about the patch,
127 other than the commit message itself. Place such "cover letter"
128 material between the three dash lines and the diffstat.
129
130 Do not attach the patch as a MIME attachment, compressed or not.
131 Do not let your e-mail client send quoted-printable. Do not let
132 your e-mail client send format=flowed which would destroy
133 whitespaces in your patches. Many
134 popular e-mail applications will not always transmit a MIME
135 attachment as plain text, making it impossible to comment on
136 your code. A MIME attachment also takes a bit more time to
137 process. This does not decrease the likelihood of your
138 MIME-attached change being accepted, but it makes it more likely
139 that it will be postponed.
140
141 Exception: If your mailer is mangling patches then someone may ask
142 you to re-send them using MIME, that is OK.
143
144 Do not PGP sign your patch, at least for now. Most likely, your
145 maintainer or other people on the list would not have your PGP
146 key and would not bother obtaining it anyway. Your patch is not
147 judged by who you are; a good patch from an unknown origin has a
148 far better chance of being accepted than a patch from a known,
149 respected origin that is done poorly or does incorrect things.
150
151 If you really really really really want to do a PGP signed
152 patch, format it as "multipart/signed", not a text/plain message
153 that starts with '-----BEGIN PGP SIGNED MESSAGE-----'. That is
154 not a text/plain, it's something else.
155
156 Note that your maintainer does not necessarily read everything
157 on the git mailing list. If your patch is for discussion first,
158 send it "To:" the mailing list, and optionally "cc:" him. If it
159 is trivially correct or after the list reached a consensus, send
160 it "To:" the maintainer and optionally "cc:" the list.
161
162 Also note that your maintainer does not actively involve himself in
163 maintaining what are in contrib/ hierarchy. When you send fixes and
164 enhancements to them, do not forget to "cc: " the person who primarily
165 worked on that hierarchy in contrib/.
166
167
168 (4) Sign your work
169
170 To improve tracking of who did what, we've borrowed the
171 "sign-off" procedure from the Linux kernel project on patches
172 that are being emailed around. Although core GIT is a lot
173 smaller project it is a good discipline to follow it.
174
175 The sign-off is a simple line at the end of the explanation for
176 the patch, which certifies that you wrote it or otherwise have
177 the right to pass it on as a open-source patch. The rules are
178 pretty simple: if you can certify the below:
179
180 Developer's Certificate of Origin 1.1
181
182 By making a contribution to this project, I certify that:
183
184 (a) The contribution was created in whole or in part by me and I
185 have the right to submit it under the open source license
186 indicated in the file; or
187
188 (b) The contribution is based upon previous work that, to the best
189 of my knowledge, is covered under an appropriate open source
190 license and I have the right under that license to submit that
191 work with modifications, whether created in whole or in part
192 by me, under the same open source license (unless I am
193 permitted to submit under a different license), as indicated
194 in the file; or
195
196 (c) The contribution was provided directly to me by some other
197 person who certified (a), (b) or (c) and I have not modified
198 it.
199
200 (d) I understand and agree that this project and the contribution
201 are public and that a record of the contribution (including all
202 personal information I submit with it, including my sign-off) is
203 maintained indefinitely and may be redistributed consistent with
204 this project or the open source license(s) involved.
205
206 then you just add a line saying
207
208 Signed-off-by: Random J Developer <random@developer.example.org>
209
210 This line can be automatically added by git if you run the git-commit
211 command with the -s option.
212
213 Some people also put extra tags at the end. They'll just be ignored for
214 now, but you can do this to mark internal company procedures or just
215 point out some special detail about the sign-off.
216
217
218 ------------------------------------------------
219 MUA specific hints
220
221 Some of patches I receive or pick up from the list share common
222 patterns of breakage. Please make sure your MUA is set up
223 properly not to corrupt whitespaces. Here are two common ones
224 I have seen:
225
226 * Empty context lines that do not have _any_ whitespace.
227
228 * Non empty context lines that have one extra whitespace at the
229 beginning.
230
231 One test you could do yourself if your MUA is set up correctly is:
232
233 * Send the patch to yourself, exactly the way you would, except
234 To: and Cc: lines, which would not contain the list and
235 maintainer address.
236
237 * Save that patch to a file in UNIX mailbox format. Call it say
238 a.patch.
239
240 * Try to apply to the tip of the "master" branch from the
241 git.git public repository:
242
243 $ git fetch http://kernel.org/pub/scm/git/git.git master:test-apply
244 $ git checkout test-apply
245 $ git reset --hard
246 $ git am a.patch
247
248 If it does not apply correctly, there can be various reasons.
249
250 * Your patch itself does not apply cleanly. That is _bad_ but
251 does not have much to do with your MUA. Please rebase the
252 patch appropriately.
253
254 * Your MUA corrupted your patch; "am" would complain that
255 the patch does not apply. Look at .dotest/ subdirectory and
256 see what 'patch' file contains and check for the common
257 corruption patterns mentioned above.
258
259 * While you are at it, check what are in 'info' and
260 'final-commit' files as well. If what is in 'final-commit' is
261 not exactly what you would want to see in the commit log
262 message, it is very likely that your maintainer would end up
263 hand editing the log message when he applies your patch.
264 Things like "Hi, this is my first patch.\n", if you really
265 want to put in the patch e-mail, should come after the
266 three-dash line that signals the end of the commit message.
267
268
269 Pine
270 ----
271
272 (Johannes Schindelin)
273
274 I don't know how many people still use pine, but for those poor
275 souls it may be good to mention that the quell-flowed-text is
276 needed for recent versions.
277
278 ... the "no-strip-whitespace-before-send" option, too. AFAIK it
279 was introduced in 4.60.
280
281 (Linus Torvalds)
282
283 And 4.58 needs at least this.
284
285 ---
286 diff-tree 8326dd8350be64ac7fc805f6563a1d61ad10d32c (from e886a61f76edf5410573e92e38ce22974f9c40f1)
287 Author: Linus Torvalds <torvalds@g5.osdl.org>
288 Date: Mon Aug 15 17:23:51 2005 -0700
289
290 Fix pine whitespace-corruption bug
291
292 There's no excuse for unconditionally removing whitespace from
293 the pico buffers on close.
294
295 diff --git a/pico/pico.c b/pico/pico.c
296 --- a/pico/pico.c
297 +++ b/pico/pico.c
298 @@ -219,7 +219,9 @@ PICO *pm;
299 switch(pico_all_done){ /* prepare for/handle final events */
300 case COMP_EXIT : /* already confirmed */
301 packheader();
302 +#if 0
303 stripwhitespace();
304 +#endif
305 c |= COMP_EXIT;
306 break;
307
308
309 (Daniel Barkalow)
310
311 > A patch to SubmittingPatches, MUA specific help section for
312 > users of Pine 4.63 would be very much appreciated.
313
314 Ah, it looks like a recent version changed the default behavior to do the
315 right thing, and inverted the sense of the configuration option. (Either
316 that or Gentoo did it.) So you need to set the
317 "no-strip-whitespace-before-send" option, unless the option you have is
318 "strip-whitespace-before-send", in which case you should avoid checking
319 it.
320
321
322 Thunderbird
323 -----------
324
325 (A Large Angry SCM)
326
327 Here are some hints on how to successfully submit patches inline using
328 Thunderbird.
329
330 This recipe appears to work with the current [*1*] Thunderbird from Suse.
331
332 The following Thunderbird extensions are needed:
333 AboutConfig 0.5
334 http://aboutconfig.mozdev.org/
335 External Editor 0.7.2
336 http://globs.org/articles.php?lng=en&pg=8
337
338 1) Prepare the patch as a text file using your method of choice.
339
340 2) Before opening a compose window, use Edit->Account Settings to
341 uncheck the "Compose messages in HTML format" setting in the
342 "Composition & Addressing" panel of the account to be used to send the
343 patch. [*2*]
344
345 3) In the main Thunderbird window, _before_ you open the compose window
346 for the patch, use Tools->about:config to set the following to the
347 indicated values:
348 mailnews.send_plaintext_flowed => false
349 mailnews.wraplength => 0
350
351 4) Open a compose window and click the external editor icon.
352
353 5) In the external editor window, read in the patch file and exit the
354 editor normally.
355
356 6) Back in the compose window: Add whatever other text you wish to the
357 message, complete the addressing and subject fields, and press send.
358
359 7) Optionally, undo the about:config/account settings changes made in
360 steps 2 & 3.
361
362
363 [Footnotes]
364 *1* Version 1.0 (20041207) from the MozillaThunderbird-1.0-5 rpm of Suse
365 9.3 professional updates.
366
367 *2* It may be possible to do this with about:config and the following
368 settings but I haven't tried, yet.
369 mail.html_compose => false
370 mail.identity.default.compose_html => false
371 mail.identity.id?.compose_html => false
372
373
374 Gnus
375 ----
376
377 '|' in the *Summary* buffer can be used to pipe the current
378 message to an external program, and this is a handy way to drive
379 "git am". However, if the message is MIME encoded, what is
380 piped into the program is the representation you see in your
381 *Article* buffer after unwrapping MIME. This is often not what
382 you would want for two reasons. It tends to screw up non ASCII
383 characters (most notably in people's names), and also
384 whitespaces (fatal in patches). Running 'C-u g' to display the
385 message in raw form before using '|' to run the pipe can work
386 this problem around.
387
388
389 KMail
390 -----
391
392 This should help you to submit patches inline using KMail.
393
394 1) Prepare the patch as a text file.
395
396 2) Click on New Mail.
397
398 3) Go under "Options" in the Composer window and be sure that
399 "Word wrap" is not set.
400
401 4) Use Message -> Insert file... and insert the patch.
402
403 5) Back in the compose window: add whatever other text you wish to the
404 message, complete the addressing and subject fields, and press send.