git-format-patch

Name

git-format-patch - Prepare patches for e-mail submission

Synopsis

git format-patch [-k] [(-o|--output-directory) <dir> | --stdout]
                   [--no-thread | --thread[=<style>]]
                   [(--attach|--inline)[=<boundary>] | --no-attach]
                   [-s | --signoff]
                   [--signature=<signature> | --no-signature]
                   [--signature-file=<file>]
                   [-n | --numbered | -N | --no-numbered]
                   [--start-number <n>] [--numbered-files]
                   [--in-reply-to=<message id>] [--suffix=.<sfx>]
                   [--ignore-if-in-upstream]
                   [--cover-from-description=<mode>]
                   [--rfc] [--subject-prefix=<subject prefix>]
                   [(--reroll-count|-v) <n>]
                   [--to=<email>] [--cc=<email>]
                   [--[no-]cover-letter] [--quiet]
                   [--[no-]encode-email-headers]
                   [--no-notes | --notes[=<ref>]]
                   [--interdiff=<previous>]
                   [--range-diff=<previous> [--creation-factor=<percent>]]
                   [--filename-max-length=<n>]
                   [--progress]
                   [<common diff options>]
                   [ <since> | <revision range> ]

Description

Prepare each non-merge commit with its "patch" in one "message" per commit, formatted to resemble a UNIX mailbox. The output of this command is convenient for e-mail submission or for use with git am.

A "message" generated by the command consists of three parts:

A brief metadata header that begins with From <commit> with a fixed Mon Sep 17 00:00:00 2001 datestamp to help programs like "file(1)" to recognize that the file is an output from this command, fields that record the author identity, the author date, and the title of the change (taken from the first paragraph of the commit log message).
The second and subsequent paragraphs of the commit log message.
The "patch", which is the "diff -p --stat" output (see git-diff[1]) between the commit and its parent.

The log message and the patch is separated by a line with a three-dash line.

There are two ways to specify which commits to operate on.

A single commit, , specifies that the commits leading to the tip of the current branch that are not in the history that leads to the to be output.
Generic expression (see "SPECIFYING REVISIONS" section in gitrevisions[7]) means the commits in the specified range.

The first rule takes precedence in the case of a single . To apply the second rule, i.e., format everything since the beginning of history up until , use the --root option: git format-patch --root <commit>. If you want to format only itself, you can do this with git format-patch -1 <commit>.

By default, each output file is numbered sequentially from 1, and uses the first line of the commit message (massaged for pathname safety) as the filename. With the --numbered-files option, the output file names will only be numbers, without the first line of the commit appended. The names of the output files are printed to standard output, unless the --stdout option is specified.

If -o is specified, output files are created in

. Otherwise they are created in the current working directory. The default path can be set with the format.outputDirectory configuration option. The -o option takes precedence over format.outputDirectory. To store patches in the current working directory even when format.outputDirectory points elsewhere, use -o .. All directory components will be created. By default, the subject of a single patch is "[PATCH] " followed by the concatenation of lines from the commit message up to the first blank line (see the DISCUSSION section of git-commit[1]).

When multiple patches are output, the subject prefix will instead be "[PATCH n/m] ". To force 1/1 to be added for a single patch, use -n. To omit patch numbers from the subject, use -N.

If given --thread, git-format-patch will generate In-Reply-To and References headers to make the second and subsequent patch mails appear as replies to the first mail; this also generates a Message-Id header to reference.

Options

-p --no-stat

Generate plain patches without any diffstats.

-U --unified=

Generate diffs with lines of context instead of the usual three.

--output=

Output to a specific file instead of stdout.

--output-indicator-new= --output-indicator-old= --output-indicator-context=

Specify the character used to indicate new, old or context lines in the generated patch. Normally they are +, - and ' ' respectively.

--indent-heuristic

Enable the heuristic that shifts diff hunk boundaries to make patches easier to read. This is the default.

--no-indent-heuristic

Disable the indent heuristic.

--minimal

Spend extra time to make sure the smallest possible diff is produced.

--patience

Generate a diff using the "patience diff" algorithm.

--histogram

Generate a diff using the "histogram diff" algorithm.

--anchored=

Generate a diff using the "anchored diff" algorithm.

This option may be specified more than once.

If a line exists in both the source and destination, exists only once, and starts with this text, this algorithm attempts to prevent it from appearing as a deletion or addition in the output. It uses the "patience diff" algorithm internally.

--diff-algorithm={patience|minimal|histogram|myers}

Choose a diff algorithm. The variants are as follows:

default, myers: The basic greedy diff algorithm. Currently, this is the default.
minimal: Spend extra time to make sure the smallest possible diff is produced.
patience: Use "patience diff" algorithm when generating patches.
histogram: This algorithm extends the patience algorithm to "support low-occurrence common elements".

For instance, if you configured the diff.algorithm variable to a non-default value and want to use the default one, then you have to use --diff-algorithm=default option.

--stat[=[,[,]]]

Generate a diffstat. By default, as much space as necessary will be used for the filename part, and the rest for the graph part. Maximum width defaults to terminal width, or 80 columns if not connected to a terminal, and can be overridden by <width>. The width of the filename part can be limited by giving another width <name-width> after a comma. The width of the graph part can be limited by using --stat-graph-width=<width> (affects all commands generating a stat graph) or by setting diff.statGraphWidth=<width> (does not affect git format-patch). By giving a third parameter <count>, you can limit the output to the first <count> lines, followed by ... if there are more.

These parameters can also be set individually with --stat-width=<width>, --stat-name-width=<name-width> and --stat-count=<count>.

--compact-summary

Output a condensed summary of extended header information such as file creations or deletions ("new" or "gone", optionally "+l" if it’s a symlink) and mode changes ("+x" or "-x" for adding or removing executable bit respectively) in diffstat. The information is put between the filename part and the graph part. Implies --stat.

--numstat

Similar to --stat, but shows number of added and deleted lines in decimal notation and pathname without abbreviation, to make it more machine friendly. For binary files, outputs two - instead of saying 0 0.

--shortstat

Output only the last line of the --stat format containing total number of modified files, as well as number of added and deleted lines.

-X[] --dirstat[=]

Output the distribution of relative amount of changes for each sub-directory. The behavior of --dirstat can be customized by passing it a comma separated list of parameters. The defaults are controlled by the diff.dirstat configuration variable (see git-config[1]). The following parameters are available:

changes: Compute the dirstat numbers by counting the lines that have been removed from the source, or added to the destination. This ignores the amount of pure code movements within a file. In other words, rearranging lines in a file is not counted as much as other changes. This is the default behavior when no parameter is given.
lines: Compute the dirstat numbers by doing the regular line-based diff analysis, and summing the removed/added line counts. (For binary files, count 64-byte chunks instead, since binary files have no natural concept of lines). This is a more expensive --dirstat behavior than the changes behavior, but it does count rearranged lines within a file as much as other changes. The resulting output is consistent with what you get from the other --*stat options.
files: Compute the dirstat numbers by counting the number of files changed. Each changed file counts equally in the dirstat analysis. This is the computationally cheapest --dirstat behavior, since it does not have to look at the file contents at all.
cumulative: Count changes in a child directory for the parent directory as well. Note that when using cumulative, the sum of the percentages reported may exceed 100%. The default (non-cumulative) behavior can be specified with the noncumulative parameter.
: An integer parameter specifies a cut-off percent (3% by default). Directories contributing less than this percentage of the changes are not shown in the output.

Example: The following will count changed files, while ignoring directories with less than 10% of the total amount of changed files, and accumulating child directory counts in the parent directories: --dirstat=files,10,cumulative.

--cumulative

Synonym for --dirstat=cumulative

--dirstat-by-file[=…]

Synonym for --dirstat=files,param1,param2…

--summary

Output a condensed summary of extended header information such as creations, renames and mode changes.

--no-renames

Turn off rename detection, even when the configuration file gives the default to do so.

--[no-]rename-empty

Whether to use empty blobs as rename source.

--full-index

Instead of the first handful of characters, show the full pre- and post-image blob object names on the "index" line when generating patch format output.

--binary

In addition to --full-index, output a binary diff that can be applied with git-apply.

--abbrev[=]

Instead of showing the full 40-byte hexadecimal object name in diff-raw format output and diff-tree header lines, show the shortest prefix that is at least <n> hexdigits long that uniquely refers the object. In diff-patch output format, --full-index takes higher precedence, i.e. if --full-index is specified, full blob names will be shown regardless of --abbrev. Non default number of digits can be specified with --abbrev=<n>.

-B[][/] --break-rewrites[=[][/]]

Break complete rewrite changes into pairs of delete and create. This serves two purposes:

It affects the way a change that amounts to a total rewrite of a file not as a series of deletion and insertion mixed together with a very few lines that happen to match textually as the context, but as a single deletion of everything old followed by a single insertion of everything new, and the number m controls this aspect of the -B option (defaults to 60%). -B/70% specifies that less than 30% of the original should remain in the result for Git to consider it a total rewrite (i.e. otherwise the resulting patch will be a series of deletion and insertion mixed together with context lines).

When used with -M, a totally-rewritten file is also considered as the source of a rename (usually -M only considers a file that disappeared as the source of a rename), and the number n controls this aspect of the -B option (defaults to 50%). -B20% specifies that a change with addition and deletion compared to 20% or more of the file’s size are eligible for being picked up as a possible source of a rename to another file.

-M[] --find-renames[=]

Detect renames. If n is specified, it is a threshold on the similarity index (i.e. amount of addition/deletions compared to the file’s size). For example, -M90% means Git should consider a delete/add pair to be a rename if more than 90% of the file hasn’t changed. Without a % sign, the number is to be read as a fraction, with a decimal point before it. I.e., -M5 becomes 0.5, and is thus the same as -M50%. Similarly, -M05 is the same as -M5%. To limit detection to exact renames, use -M100%. The default similarity index is 50%.

-C[] --find-copies[=]

Detect copies as well as renames. See also --find-copies-harder. If n is specified, it has the same meaning as for -M<n>.

--find-copies-harder

For performance reasons, by default, -C option finds copies only if the original file of the copy was modified in the same changeset. This flag makes the command inspect unmodified files as candidates for the source of copy. This is a very expensive operation for large projects, so use it with caution. Giving more than one -C option has the same effect.

-D --irreversible-delete

Omit the preimage for deletes, i.e. print only the header but not the diff between the preimage and /dev/null. The resulting patch is not meant to be applied with patch or git apply; this is solely for people who want to just concentrate on reviewing the text after the change. In addition, the output obviously lacks enough information to apply such a patch in reverse, even manually, hence the name of the option.

When used together with -B, omit also the preimage in the deletion part of a delete/create pair.

-l

The -M and -C options involve some preliminary steps that can detect subsets of renames/copies cheaply, followed by an exhaustive fallback portion that compares all remaining unpaired destinations to all relevant sources. (For renames, only remaining unpaired sources are relevant; for copies, all original sources are relevant.) For N sources and destinations, this exhaustive check is O(N^2). This option prevents the exhaustive portion of rename/copy detection from running if the number of source/destination files involved exceeds the specified number. Defaults to diff.renameLimit. Note that a value of 0 is treated as unlimited.

-O

Control the order in which files appear in the output. This overrides the diff.orderFile configuration variable (see git-config[1]). To cancel diff.orderFile, use -O/dev/null.

The output order is determined by the order of glob patterns in . All files with pathnames that match the first pattern are output first, all files with pathnames that match the second pattern (but not the first) are output next, and so on. All files with pathnames that do not match any pattern are output last, as if there was an implicit match-all pattern at the end of the file. If multiple pathnames have the same rank (they match the same pattern but no earlier patterns), their output order relative to each other is the normal order.

is parsed as follows:

Blank lines are ignored, so they can be used as separators for readability.
Lines starting with a hash ("#") are ignored, so they can be used for comments. Add a backslash ("\") to the beginning of the pattern if it starts with a hash.
Each other line contains a single pattern.

Patterns have the same syntax and semantics as patterns used for fnmatch(3) without the FNM_PATHNAME flag, except a pathname also matches a pattern if removing any number of the final pathname components matches the pattern. For example, the pattern "foo*bar" matches "fooasdfbar" and "foo/bar/baz/asdf" but not "foobarx".

--skip-to= --rotate-to=

Discard the files before the named from the output (i.e. skip to), or move them to the end of the output (i.e. rotate to). These were invented primarily for use of the git difftool command, and may not be very useful otherwise.

--relative[=] --no-relative

When run from a subdirectory of the project, it can be told to exclude changes outside the directory and show pathnames relative to it with this option. When you are not in a subdirectory (e.g. in a bare repository), you can name which subdirectory to make the output relative to by giving a as an argument. --no-relative can be used to countermand both diff.relative config option and previous --relative.

-a --text

Treat all files as text.

--ignore-cr-at-eol

Ignore carriage-return at the end of line when doing a comparison.

--ignore-space-at-eol

Ignore changes in whitespace at EOL.

-b --ignore-space-change

Ignore changes in amount of whitespace. This ignores whitespace at line end, and considers all other sequences of one or more whitespace characters to be equivalent.

-w --ignore-all-space

Ignore whitespace when comparing lines. This ignores differences even if one line has whitespace where the other line has none.

--ignore-blank-lines

Ignore changes whose lines are all blank.

-I --ignore-matching-lines=

Ignore changes whose all lines match . This option may be specified more than once.

--inter-hunk-context=

Show the context between diff hunks, up to the specified number of lines, thereby fusing hunks that are close to each other. Defaults to diff.interHunkContext or 0 if the config option is unset.

-W --function-context

Show whole function as context lines for each change. The function names are determined in the same way as git diff works out patch hunk headers (see Defining a custom hunk-header in gitattributes[5]).

--ext-diff

Allow an external diff helper to be executed. If you set an external diff driver with gitattributes[5], you need to use this option with git-log[1] and friends.

--no-ext-diff

Disallow external diff drivers.

--textconv --no-textconv

Allow (or disallow) external text conversion filters to be run when comparing binary files. See gitattributes[5] for details. Because textconv filters are typically a one-way conversion, the resulting diff is suitable for human consumption, but cannot be applied. For this reason, textconv filters are enabled by default only for git-diff[1] and git-log[1], but not for git-format-patch[1] or diff plumbing commands.

--ignore-submodules[=]

Ignore changes to submodules in the diff generation. can be either "none", "untracked", "dirty" or "all", which is the default. Using "none" will consider the submodule modified when it either contains untracked or modified files or its HEAD differs from the commit recorded in the superproject and can be used to override any settings of the ignore option in git-config[1] or gitmodules[5]. When "untracked" is used submodules are not considered dirty when they only contain untracked content (but they are still scanned for modified content). Using "dirty" ignores all changes to the work tree of submodules, only changes to the commits stored in the superproject are shown (this was the behavior until 1.7.0). Using "all" hides all changes to submodules.

--src-prefix=

Show the given source prefix instead of "a/".

--dst-prefix=

Show the given destination prefix instead of "b/".

--no-prefix

Do not show any source or destination prefix.

--line-prefix=

Prepend an additional prefix to every line of output.

--ita-invisible-in-index

By default entries added by "git add -N" appear as an existing empty file in "git diff" and a new file in "git diff --cached". This option makes the entry appear as a new file in "git diff" and non-existent in "git diff --cached". This option could be reverted with --ita-visible-in-index. Both options are experimental and could be removed in future.

For more detailed explanation on these common options, see also gitdiffcore[7].

- Prepare patches from the topmost commits.

-o --output-directory Use

to store the resulting files, instead of the current working directory. -n --numbered Name output in [PATCH n/m] format, even with a single patch.

-N --no-numbered Name output in [PATCH] format.

--start-number Start numbering the patches at instead of 1.

--numbered-files Output file names will be a simple number sequence without the default first line of the commit appended.

-k --keep-subject Do not strip/add [PATCH] from the first line of the commit log message.

-s --signoff Add a Signed-off-by trailer to the commit message, using the committer identity of yourself. See the signoff option in git-commit[1] for more information.

--stdout Print all commits to the standard output in mbox format, instead of creating a file for each one.

--attach[=] Create multipart/mixed attachment, the first part of which is the commit message and the patch itself in the second part, with Content-Disposition: attachment.

--no-attach Disable the creation of an attachment, overriding the configuration setting.

--inline[=] Create multipart/mixed attachment, the first part of which is the commit message and the patch itself in the second part, with Content-Disposition: inline.

--thread[=