Doc: add more detail for git-format-patch
[git/git.git] / Documentation / git-format-patch.txt
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1git-format-patch(1)
2===================
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3
4NAME
5----
7bd7f280 6git-format-patch - Prepare patches for e-mail submission
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7
8
9SYNOPSIS
10--------
353ce815 11[verse]
50710ce4 12'git format-patch' [-k] [(-o|--output-directory) <dir> | --stdout]
f693b7e9 13 [--no-thread | --thread[=<style>]]
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14 [(--attach|--inline)[=<boundary>] | --no-attach]
15 [-s | --signoff]
6622d9c7 16 [--signature=<signature> | --no-signature]
7022650f 17 [--signature-file=<file>]
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18 [-n | --numbered | -N | --no-numbered]
19 [--start-number <n>] [--numbered-files]
c1a6f21c 20 [--in-reply-to=<message id>] [--suffix=.<sfx>]
a5a27c79 21 [--ignore-if-in-upstream]
c1a6f21c 22 [--rfc] [--subject-prefix=<subject prefix>]
68e83a5b 23 [(--reroll-count|-v) <n>]
ae6c098f 24 [--to=<email>] [--cc=<email>]
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25 [--[no-]cover-letter] [--quiet]
26 [--no-notes | --notes[=<ref>]]
126facf8 27 [--interdiff=<previous>]
8631bf1c 28 [--range-diff=<previous> [--creation-factor=<percent>]]
738e88a2 29 [--progress]
50710ce4 30 [<common diff options>]
8a1d076e 31 [ <since> | <revision range> ]
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32
33DESCRIPTION
34-----------
2052d146 35
8a1d076e 36Prepare each commit with its patch in
2052d146 37one file per commit, formatted to resemble UNIX mailbox format.
2052d146 38The output of this command is convenient for e-mail submission or
0b444cdb 39for use with 'git am'.
35ef3a4c 40
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41There are two ways to specify which commits to operate on.
42
431. A single commit, <since>, specifies that the commits leading
44 to the tip of the current branch that are not in the history
45 that leads to the <since> to be output.
46
472. Generic <revision range> expression (see "SPECIFYING
9d83e382 48 REVISIONS" section in linkgit:gitrevisions[7]) means the
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49 commits in the specified range.
50
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51The first rule takes precedence in the case of a single <commit>. To
52apply the second rule, i.e., format everything since the beginning of
9e9f132f 53history up until <commit>, use the `--root` option: `git format-patch
6cf378f0 54--root <commit>`. If you want to format only <commit> itself, you
dce5ef14 55can do this with `git format-patch -1 <commit>`.
8a1d076e 56
e6ff0f42 57By default, each output file is numbered sequentially from 1, and uses the
2052d146 58first line of the commit message (massaged for pathname safety) as
dce5ef14 59the filename. With the `--numbered-files` option, the output file names
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60will only be numbers, without the first line of the commit appended.
61The names of the output files are printed to standard
dce5ef14 62output, unless the `--stdout` option is specified.
66f04f38 63
dce5ef14 64If `-o` is specified, output files are created in <dir>. Otherwise
bc6bf2d7 65they are created in the current working directory. The default path
ae9f6311 66can be set with the `format.outputDirectory` configuration option.
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67The `-o` option takes precedence over `format.outputDirectory`.
68To store patches in the current working directory even when
69`format.outputDirectory` points elsewhere, use `-o .`.
35ef3a4c 70
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71By default, the subject of a single patch is "[PATCH] " followed by
72the concatenation of lines from the commit message up to the first blank
73line (see the DISCUSSION section of linkgit:git-commit[1]).
74
75When multiple patches are output, the subject prefix will instead be
76"[PATCH n/m] ". To force 1/1 to be added for a single patch, use `-n`.
77To omit patch numbers from the subject, use `-N`.
35ef3a4c 78
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79If given `--thread`, `git-format-patch` will generate `In-Reply-To` and
80`References` headers to make the second and subsequent patch mails appear
81as replies to the first mail; this also generates a `Message-Id` header to
cc35de84 82reference.
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83
84OPTIONS
85-------
c1a95fa6 86:git-format-patch: 1
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87include::diff-options.txt[]
88
ed5f07a6 89-<n>::
2c642ed8 90 Prepare patches from the topmost <n> commits.
ed5f07a6 91
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92-o <dir>::
93--output-directory <dir>::
35ef3a4c 94 Use <dir> to store the resulting files, instead of the
efd02016 95 current working directory.
35ef3a4c 96
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97-n::
98--numbered::
a567fdcb 99 Name output in '[PATCH n/m]' format, even with a single patch.
35ef3a4c 100
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101-N::
102--no-numbered::
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103 Name output in '[PATCH]' format.
104
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105--start-number <n>::
106 Start numbering the patches at <n> instead of 1.
107
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108--numbered-files::
109 Output file names will be a simple number sequence
110 without the default first line of the commit appended.
e6ff0f42 111
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112-k::
113--keep-subject::
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114 Do not strip/add '[PATCH]' from the first line of the
115 commit log message.
116
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117-s::
118--signoff::
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119 Add `Signed-off-by:` line to the commit message, using
120 the committer identity of yourself.
b2c150d3 121 See the signoff option in linkgit:git-commit[1] for more information.
6f855371 122
54ba6013 123--stdout::
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124 Print all commits to the standard output in mbox format,
125 instead of creating a file for each one.
7fc9d69f 126
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127--attach[=<boundary>]::
128 Create multipart/mixed attachment, the first part of
129 which is the commit message and the patch itself in the
dce5ef14 130 second part, with `Content-Disposition: attachment`.
c112f689 131
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132--no-attach::
133 Disable the creation of an attachment, overriding the
134 configuration setting.
135
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136--inline[=<boundary>]::
137 Create multipart/mixed attachment, the first part of
138 which is the commit message and the patch itself in the
dce5ef14 139 second part, with `Content-Disposition: inline`.
a15a44ef 140
30984ed2 141--thread[=<style>]::
f693b7e9 142--no-thread::
dce5ef14 143 Controls addition of `In-Reply-To` and `References` headers to
f693b7e9 144 make the second and subsequent mails appear as replies to the
dce5ef14 145 first. Also controls generation of the `Message-Id` header to
f693b7e9 146 reference.
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147+
148The optional <style> argument can be either `shallow` or `deep`.
fd1ff306 149'shallow' threading makes every mail a reply to the head of the
30984ed2 150series, where the head is chosen from the cover letter, the
6cf378f0 151`--in-reply-to`, and the first patch mail, in this order. 'deep'
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152threading makes every mail a reply to the previous one.
153+
ae9f6311 154The default is `--no-thread`, unless the `format.thread` configuration
dce5ef14 155is set. If `--thread` is specified without a style, it defaults to the
ae9f6311 156style specified by `format.thread` if any, or else `shallow`.
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157+
158Beware that the default for 'git send-email' is to thread emails
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159itself. If you want `git format-patch` to take care of threading, you
160will want to ensure that threading is disabled for `git send-email`.
28ffb898 161
c1a6f21c 162--in-reply-to=<message id>::
dce5ef14 163 Make the first mail (or all the mails with `--no-thread`) appear as a
c1a6f21c 164 reply to the given <message id>, which avoids breaking threads to
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165 provide a new patch series.
166
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167--ignore-if-in-upstream::
168 Do not include a patch that matches a commit in
169 <until>..<since>. This will examine all patches reachable
170 from <since> but not from <until> and compare them with the
171 patches being generated, and any patch that matches is
172 ignored.
173
c1a6f21c 174--subject-prefix=<subject prefix>::
2d9e4a47 175 Instead of the standard '[PATCH]' prefix in the subject
c1a6f21c 176 line, instead use '[<subject prefix>]'. This
2d9e4a47 177 allows for useful naming of a patch series, and can be
dce5ef14 178 combined with the `--numbered` option.
2d9e4a47 179
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180--rfc::
181 Alias for `--subject-prefix="RFC PATCH"`. RFC means "Request For
182 Comments"; use this when sending an experimental patch for
183 discussion rather than application.
184
7952ea66 185-v <n>::
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186--reroll-count=<n>::
187 Mark the series as the <n>-th iteration of the topic. The
d614f075 188 output filenames have `v<n>` prepended to them, and the
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189 subject prefix ("PATCH" by default, but configurable via the
190 `--subject-prefix` option) has ` v<n>` appended to it. E.g.
191 `--reroll-count=4` may produce `v4-0001-add-makefile.patch`
192 file that has "Subject: [PATCH v4 1/20] Add makefile" in it.
193
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194--to=<email>::
195 Add a `To:` header to the email headers. This is in addition
196 to any configured headers, and may be used multiple times.
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197 The negated form `--no-to` discards all `To:` headers added so
198 far (from config or command line).
ae6c098f 199
736cc67d 200--cc=<email>::
dce5ef14 201 Add a `Cc:` header to the email headers. This is in addition
736cc67d 202 to any configured headers, and may be used multiple times.
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203 The negated form `--no-cc` discards all `Cc:` headers added so
204 far (from config or command line).
736cc67d 205
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206--from::
207--from=<ident>::
208 Use `ident` in the `From:` header of each commit email. If the
209 author ident of the commit is not textually identical to the
210 provided `ident`, place a `From:` header in the body of the
211 message with the original author. If no `ident` is given, use
212 the committer ident.
213+
214Note that this option is only useful if you are actually sending the
215emails and want to identify yourself as the sender, but retain the
216original author (and `git am` will correctly pick up the in-body
217header). Note also that `git send-email` already handles this
218transformation for you, and this option should not be used if you are
219feeding the result to `git send-email`.
220
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221--add-header=<header>::
222 Add an arbitrary header to the email headers. This is in addition
223 to any configured headers, and may be used multiple times.
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224 For example, `--add-header="Organization: git-foo"`.
225 The negated form `--no-add-header` discards *all* (`To:`,
226 `Cc:`, and custom) headers added so far from config or command
227 line.
d7d9c2d0 228
2a4c2607 229--[no-]cover-letter::
f4912391 230 In addition to the patches, generate a cover letter file
561d2b79 231 containing the branch description, shortlog and the overall diffstat. You can
f4912391 232 fill in a description in the file before sending it out.
a5a27c79 233
126facf8 234--interdiff=<previous>::
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235 As a reviewer aid, insert an interdiff into the cover letter,
236 or as commentary of the lone patch of a 1-patch series, showing
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237 the differences between the previous version of the patch series and
238 the series currently being formatted. `previous` is a single revision
239 naming the tip of the previous series which shares a common base with
240 the series being formatted (for example `git format-patch
241 --cover-letter --interdiff=feature/v1 -3 feature/v2`).
242
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243--range-diff=<previous>::
244 As a reviewer aid, insert a range-diff (see linkgit:git-range-diff[1])
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245 into the cover letter, or as commentary of the lone patch of a
246 1-patch series, showing the differences between the previous
31e2617a 247 version of the patch series and the series currently being formatted.
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248 `previous` can be a single revision naming the tip of the previous
249 series if it shares a common base with the series being formatted (for
31e2617a 250 example `git format-patch --cover-letter --range-diff=feature/v1 -3
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251 feature/v2`), or a revision range if the two versions of the series are
252 disjoint (for example `git format-patch --cover-letter
253 --range-diff=feature/v1~3..feature/v1 -3 feature/v2`).
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254+
255Note that diff options passed to the command affect how the primary
256product of `format-patch` is generated, and they are not passed to
257the underlying `range-diff` machinery used to generate the cover-letter
258material (this may change in the future).
31e2617a 259
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260--creation-factor=<percent>::
261 Used with `--range-diff`, tweak the heuristic which matches up commits
262 between the previous and current series of patches by adjusting the
263 creation/deletion cost fudge factor. See linkgit:git-range-diff[1])
264 for details.
265
e422c0cf 266--notes[=<ref>]::
83d9db78 267--no-notes::
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268 Append the notes (see linkgit:git-notes[1]) for the commit
269 after the three-dash line.
270+
271The expected use case of this is to write supporting explanation for
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272the commit that does not belong to the commit log message proper,
273and include it with the patch submission. While one can simply write
274these explanations after `format-patch` has run but before sending,
2de9b711 275keeping them as Git notes allows them to be maintained between versions
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276of the patch series (but see the discussion of the `notes.rewrite`
277configuration options in linkgit:git-notes[1] to use this workflow).
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278+
279The default is `--no-notes`, unless the `format.notes` configuration is
280set.
e422c0cf 281
2c7ee986 282--[no-]signature=<signature>::
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283 Add a signature to each message produced. Per RFC 3676 the signature
284 is separated from the body by a line with '-- ' on it. If the
2de9b711 285 signature option is omitted the signature defaults to the Git version
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286 number.
287
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288--signature-file=<file>::
289 Works just like --signature except the signature is read from a file.
290
03eeaeae 291--suffix=.<sfx>::
917a8f89 292 Instead of using `.patch` as the suffix for generated
02783075 293 filenames, use specified suffix. A common alternative is
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294 `--suffix=.txt`. Leaving this empty will remove the `.patch`
295 suffix.
03eeaeae 296+
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297Note that the leading character does not have to be a dot; for example,
298you can use `--suffix=-patch` to get `0001-description-of-my-change-patch`.
03eeaeae 299
b7df098c 300-q::
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301--quiet::
302 Do not print the names of the generated files to standard output.
303
37c22a4b 304--no-binary::
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305 Do not output contents of changes in binary files, instead
306 display a notice that those files changed. Patches generated
307 using this option cannot be applied properly, but they are
308 still useful for code review.
37c22a4b 309
3a30aa17 310--zero-commit::
311 Output an all-zero hash in each patch's From header instead
312 of the hash of the commit.
313
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314--base=<commit>::
315 Record the base tree information to identify the state the
316 patch series applies to. See the BASE TREE INFORMATION section
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317 below for details. If <commit> is "auto", a base commit is
318 automatically chosen.
fa2ab86d 319
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320--root::
321 Treat the revision argument as a <revision range>, even if it
322 is just a single commit (that would normally be treated as a
323 <since>). Note that root commits included in the specified
324 range are always formatted as creation patches, independently
325 of this flag.
326
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327--progress::
328 Show progress reports on stderr as patches are generated.
329
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330CONFIGURATION
331-------------
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332You can specify extra mail header lines to be added to each message,
333defaults for the subject prefix and file suffix, number patches when
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334outputting more than one patch, add "To:" or "Cc:" headers, configure
335attachments, change the patch output directory, and sign off patches
336with configuration variables.
96ce6d26 337
917a8f89 338------------
96ce6d26 339[format]
7f9d77f2 340 headers = "Organization: git-foo\n"
da0005b8 341 subjectPrefix = CHANGE
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342 suffix = .txt
343 numbered = auto
ae6c098f 344 to = <email>
fe8928e6 345 cc = <email>
0db5260b 346 attach [ = mime-boundary-string ]
da0005b8 347 signOff = true
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348 outputDirectory = <directory>
349 coverLetter = auto
917a8f89 350------------
03eeaeae 351
96ce6d26 352
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353DISCUSSION
354----------
355
356The patch produced by 'git format-patch' is in UNIX mailbox format,
357with a fixed "magic" time stamp to indicate that the file is output
358from format-patch rather than a real mailbox, like so:
359
360------------
361From 8f72bad1baf19a53459661343e21d6491c3908d3 Mon Sep 17 00:00:00 2001
362From: Tony Luck <tony.luck@intel.com>
363Date: Tue, 13 Jul 2010 11:42:54 -0700
364Subject: [PATCH] =?UTF-8?q?[IA64]=20Put=20ia64=20config=20files=20on=20the=20?=
365 =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig=20diet?=
366MIME-Version: 1.0
367Content-Type: text/plain; charset=UTF-8
368Content-Transfer-Encoding: 8bit
369
370arch/arm config files were slimmed down using a python script
371(See commit c2330e286f68f1c408b4aa6515ba49d57f05beae comment)
372
373Do the same for ia64 so we can have sleek & trim looking
374...
375------------
376
377Typically it will be placed in a MUA's drafts folder, edited to add
378timely commentary that should not go in the changelog after the three
379dashes, and then sent as a message whose body, in our example, starts
380with "arch/arm config files were...". On the receiving end, readers
381can save interesting patches in a UNIX mailbox and apply them with
382linkgit:git-am[1].
383
384When a patch is part of an ongoing discussion, the patch generated by
385'git format-patch' can be tweaked to take advantage of the 'git am
386--scissors' feature. After your response to the discussion comes a
387line that consists solely of "`-- >8 --`" (scissors and perforation),
388followed by the patch with unnecessary header fields removed:
389
390------------
391...
392> So we should do such-and-such.
393
394Makes sense to me. How about this patch?
395
396-- >8 --
397Subject: [IA64] Put ia64 config files on the Uwe Kleine-König diet
398
399arch/arm config files were slimmed down using a python script
400...
401------------
402
403When sending a patch this way, most often you are sending your own
404patch, so in addition to the "`From $SHA1 $magic_timestamp`" marker you
405should omit `From:` and `Date:` lines from the patch file. The patch
406title is likely to be different from the subject of the discussion the
407patch is in response to, so it is likely that you would want to keep
408the Subject: line, like the example above.
409
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410Checking for patch corruption
411~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
412Many mailers if not set up properly will corrupt whitespace. Here are
413two common types of corruption:
414
415* Empty context lines that do not have _any_ whitespace.
416
417* Non-empty context lines that have one extra whitespace at the
418 beginning.
419
420One way to test if your MUA is set up correctly is:
421
422* Send the patch to yourself, exactly the way you would, except
423 with To: and Cc: lines that do not contain the list and
424 maintainer address.
425
426* Save that patch to a file in UNIX mailbox format. Call it a.patch,
427 say.
428
429* Apply it:
430
431 $ git fetch <project> master:test-apply
328c6cb8 432 $ git switch test-apply
80f537f7 433 $ git restore --source=HEAD --staged --worktree :/
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434 $ git am a.patch
435
436If it does not apply correctly, there can be various reasons.
437
438* The patch itself does not apply cleanly. That is _bad_ but
439 does not have much to do with your MUA. You might want to rebase
440 the patch with linkgit:git-rebase[1] before regenerating it in
441 this case.
442
443* The MUA corrupted your patch; "am" would complain that
444 the patch does not apply. Look in the .git/rebase-apply/ subdirectory and
445 see what 'patch' file contains and check for the common
446 corruption patterns mentioned above.
447
448* While at it, check the 'info' and 'final-commit' files as well.
449 If what is in 'final-commit' is not exactly what you would want to
450 see in the commit log message, it is very likely that the
451 receiver would end up hand editing the log message when applying
452 your patch. Things like "Hi, this is my first patch.\n" in the
453 patch e-mail should come after the three-dash line that signals
454 the end of the commit message.
455
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456MUA-SPECIFIC HINTS
457------------------
458Here are some hints on how to successfully submit patches inline using
459various mailers.
460
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461GMail
462~~~~~
463GMail does not have any way to turn off line wrapping in the web
464interface, so it will mangle any emails that you send. You can however
465use "git send-email" and send your patches through the GMail SMTP server, or
466use any IMAP email client to connect to the google IMAP server and forward
467the emails through that.
468
469For hints on using 'git send-email' to send your patches through the
470GMail SMTP server, see the EXAMPLE section of linkgit:git-send-email[1].
471
472For hints on submission using the IMAP interface, see the EXAMPLE
473section of linkgit:git-imap-send[1].
474
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475Thunderbird
476~~~~~~~~~~~
477By default, Thunderbird will both wrap emails as well as flag
478them as being 'format=flowed', both of which will make the
2de9b711 479resulting email unusable by Git.
dc53151f 480
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481There are three different approaches: use an add-on to turn off line wraps,
482configure Thunderbird to not mangle patches, or use
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483an external editor to keep Thunderbird from mangling the patches.
484
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485Approach #1 (add-on)
486^^^^^^^^^^^^^^^^^^^^
487
488Install the Toggle Word Wrap add-on that is available from
489https://addons.mozilla.org/thunderbird/addon/toggle-word-wrap/
490It adds a menu entry "Enable Word Wrap" in the composer's "Options" menu
491that you can tick off. Now you can compose the message as you otherwise do
492(cut + paste, 'git format-patch' | 'git imap-send', etc), but you have to
493insert line breaks manually in any text that you type.
494
495Approach #2 (configuration)
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496^^^^^^^^^^^^^^^^^^^^^^^^^^^
497Three steps:
498
4991. Configure your mail server composition as plain text:
500 Edit...Account Settings...Composition & Addressing,
501 uncheck "Compose Messages in HTML".
502
5032. Configure your general composition window to not wrap.
504+
505In Thunderbird 2:
506Edit..Preferences..Composition, wrap plain text messages at 0
507+
508In Thunderbird 3:
509Edit..Preferences..Advanced..Config Editor. Search for
510"mail.wrap_long_lines".
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511Toggle it to make sure it is set to `false`. Also, search for
512"mailnews.wraplength" and set the value to 0.
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513
5143. Disable the use of format=flowed:
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515 Edit..Preferences..Advanced..Config Editor. Search for
516 "mailnews.send_plaintext_flowed".
517 Toggle it to make sure it is set to `false`.
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518
519After that is done, you should be able to compose email as you
520otherwise would (cut + paste, 'git format-patch' | 'git imap-send', etc),
521and the patches will not be mangled.
522
b8959605 523Approach #3 (external editor)
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524^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
525
526The following Thunderbird extensions are needed:
527AboutConfig from http://aboutconfig.mozdev.org/ and
528External Editor from http://globs.org/articles.php?lng=en&pg=8
529
5301. Prepare the patch as a text file using your method of choice.
531
5322. Before opening a compose window, use Edit->Account Settings to
533 uncheck the "Compose messages in HTML format" setting in the
534 "Composition & Addressing" panel of the account to be used to
535 send the patch.
536
5373. In the main Thunderbird window, 'before' you open the compose
538 window for the patch, use Tools->about:config to set the
539 following to the indicated values:
540+
541----------
542 mailnews.send_plaintext_flowed => false
543 mailnews.wraplength => 0
544----------
545
5464. Open a compose window and click the external editor icon.
547
5485. In the external editor window, read in the patch file and exit
549 the editor normally.
550
551Side note: it may be possible to do step 2 with
552about:config and the following settings but no one's tried yet.
553
554----------
555 mail.html_compose => false
556 mail.identity.default.compose_html => false
557 mail.identity.id?.compose_html => false
558----------
559
560There is a script in contrib/thunderbird-patch-inline which can help
561you include patches with Thunderbird in an easy way. To use it, do the
562steps above and then use the script as the external editor.
563
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564KMail
565~~~~~
566This should help you to submit patches inline using KMail.
567
5681. Prepare the patch as a text file.
569
5702. Click on New Mail.
571
5723. Go under "Options" in the Composer window and be sure that
573 "Word wrap" is not set.
574
5754. Use Message -> Insert file... and insert the patch.
576
5775. Back in the compose window: add whatever other text you wish to the
578 message, complete the addressing and subject fields, and press send.
579
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580BASE TREE INFORMATION
581---------------------
582
583The base tree information block is used for maintainers or third party
584testers to know the exact state the patch series applies to. It consists
585of the 'base commit', which is a well-known commit that is part of the
586stable part of the project history everybody else works off of, and zero
587or more 'prerequisite patches', which are well-known patches in flight
588that is not yet part of the 'base commit' that need to be applied on top
589of 'base commit' in topological order before the patches can be applied.
590
591The 'base commit' is shown as "base-commit: " followed by the 40-hex of
592the commit object name. A 'prerequisite patch' is shown as
593"prerequisite-patch-id: " followed by the 40-hex 'patch id', which can
594be obtained by passing the patch through the `git patch-id --stable`
595command.
596
597Imagine that on top of the public commit P, you applied well-known
598patches X, Y and Z from somebody else, and then built your three-patch
599series A, B, C, the history would be like:
600
601................................................
602---P---X---Y---Z---A---B---C
603................................................
604
605With `git format-patch --base=P -3 C` (or variants thereof, e.g. with
7ba1ceef 606`--cover-letter` or using `Z..C` instead of `-3 C` to specify the
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607range), the base tree information block is shown at the end of the
608first message the command outputs (either the first patch, or the
609cover letter), like this:
610
611------------
612base-commit: P
613prerequisite-patch-id: X
614prerequisite-patch-id: Y
615prerequisite-patch-id: Z
616------------
617
618For non-linear topology, such as
619
620................................................
621---P---X---A---M---C
622 \ /
623 Y---Z---B
624................................................
625
626You can also use `git format-patch --base=P -3 C` to generate patches
627for A, B and C, and the identifiers for P, X, Y, Z are appended at the
628end of the first message.
e0d48279 629
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630If set `--base=auto` in cmdline, it will track base commit automatically,
631the base commit will be the merge base of tip commit of the remote-tracking
632branch and revision-range specified in cmdline.
633For a local branch, you need to track a remote branch by `git branch
634--set-upstream-to` before using this option.
635
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636EXAMPLES
637--------
638
921177f5 639* Extract commits between revisions R1 and R2, and apply them on top of
ba170517 640 the current branch using 'git am' to cherry-pick them:
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641+
642------------
467c0197 643$ git format-patch -k --stdout R1..R2 | git am -3 -k
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644------------
645
646* Extract all commits which are in the current branch but not in the
ba170517 647 origin branch:
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648+
649------------
650$ git format-patch origin
651------------
652+
653For each commit a separate file is created in the current directory.
654
655* Extract all commits that lead to 'origin' since the inception of the
ba170517 656 project:
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657+
658------------
9c67c757 659$ git format-patch --root origin
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660------------
661
662* The same as the previous one:
663+
664------------
665$ git format-patch -M -B origin
666------------
667+
668Additionally, it detects and handles renames and complete rewrites
669intelligently to produce a renaming patch. A renaming patch reduces
50710ce4 670the amount of text output, and generally makes it easier to review.
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671Note that non-Git "patch" programs won't understand renaming patches, so
672use it only when you know the recipient uses Git to apply your patch.
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673
674* Extract three topmost commits from the current branch and format them
ba170517 675 as e-mailable patches:
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676+
677------------
678$ git format-patch -3
679------------
28ffb898 680
56ae8df5 681SEE ALSO
28ffb898 682--------
5162e697 683linkgit:git-am[1], linkgit:git-send-email[1]
28ffb898 684
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685GIT
686---
9e1f0a85 687Part of the linkgit:git[1] suite