'\" t .\" Title: git-interpret-trailers .\" Author: [FIXME: author] [see http://www.docbook.org/tdg5/en/html/author] .\" Generator: DocBook XSL Stylesheets vsnapshot .\" Date: 01/05/2024 .\" Manual: Git Manual .\" Source: Git 2.43.0.381.gb435a96ce8 .\" Language: English .\" .TH "GIT\-INTERPRET\-TRAILERS" "1" "01/05/2024" "Git 2\&.43\&.0\&.381\&.gb435a9" "Git Manual" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH "NAME" git-interpret-trailers \- Add or parse structured information in commit messages .SH "SYNOPSIS" .sp .nf \fIgit interpret\-trailers\fR [\-\-in\-place] [\-\-trim\-empty] [(\-\-trailer (|)[(=|:)])\&...] [\-\-parse] [\&...] .fi .sp .SH "DESCRIPTION" .sp Add or parse \fItrailer\fR lines that look similar to RFC 822 e\-mail headers, at the end of the otherwise free\-form part of a commit message\&. For example, in the following commit message .sp .if n \{\ .RS 4 .\} .nf subject Lorem ipsum dolor sit amet, consectetur adipiscing elit\&. Signed\-off\-by: Alice Signed\-off\-by: Bob .fi .if n \{\ .RE .\} .sp .sp the last two lines starting with "Signed\-off\-by" are trailers\&. .sp This command reads commit messages from either the arguments or the standard input if no is specified\&. If \fB\-\-parse\fR is specified, the output consists of the parsed trailers coming from the input, without influencing them with any command line options or configuration variables\&. .sp Otherwise, this command applies \fBtrailer\&.*\fR configuration variables (which could potentially add new trailers, as well as reposition them), as well as any command line arguments that can override configuration variables (such as \fB\-\-trailer=\&.\&.\&.\fR which could also add new trailers), to each input file\&. The result is emitted on the standard output\&. .sp This command can also operate on the output of \fBgit-format-patch\fR(1), which is more elaborate than a plain commit message\&. Namely, such output includes a commit message (as above), a "\-\-\-" divider line, and a patch part\&. For these inputs, the divider and patch parts are not modified by this command and are emitted as is on the output, unless \fB\-\-no\-divider\fR is specified\&. .sp Some configuration variables control the way the \fB\-\-trailer\fR arguments are applied to each input and the way any existing trailer in the input is changed\&. They also make it possible to automatically add some trailers\&. .sp By default, a \fI=\fR or \fI:\fR argument given using \fB\-\-trailer\fR will be appended after the existing trailers only if the last trailer has a different (, ) pair (or if there is no existing trailer)\&. The and parts will be trimmed to remove starting and trailing whitespace, and the resulting trimmed and will appear in the output like this: .sp .if n \{\ .RS 4 .\} .nf key: value .fi .if n \{\ .RE .\} .sp .sp This means that the trimmed and will be separated by \fB\*(Aq: \*(Aq\fR (one colon followed by one space)\&. .sp For convenience, a can be configured to make using \fB\-\-trailer\fR shorter to type on the command line\&. This can be configured using the \fItrailer\&.\&.key\fR configuration variable\&. The must be a prefix of the full string, although case sensitivity does not matter\&. For example, if you have .sp .if n \{\ .RS 4 .\} .nf trailer\&.sign\&.key "Signed\-off\-by: " .fi .if n \{\ .RE .\} .sp .sp in your configuration, you only need to specify \fB\-\-trailer="sign: foo"\fR on the command line instead of \fB\-\-trailer="Signed\-off\-by: foo"\fR\&. .sp By default the new trailer will appear at the end of all the existing trailers\&. If there is no existing trailer, the new trailer will appear at the end of the input\&. A blank line will be added before the new trailer if there isn\(cqt one already\&. .sp Existing trailers are extracted from the input by looking for a group of one or more lines that (i) is all trailers, or (ii) contains at least one Git\-generated or user\-configured trailer and consists of at least 25% trailers\&. The group must be preceded by one or more empty (or whitespace\-only) lines\&. The group must either be at the end of the input or be the last non\-whitespace lines before a line that starts with \fI\-\-\-\fR (followed by a space or the end of the line)\&. .sp When reading trailers, there can be no whitespace before or inside the , but any number of regular space and tab characters are allowed between the and the separator\&. There can be whitespaces before, inside or after the \&. The may be split over multiple lines with each subsequent line starting with at least one whitespace, like the "folding" in RFC 822\&. Example: .sp .if n \{\ .RS 4 .\} .nf key: This is a very long value, with spaces and newlines in it\&. .fi .if n \{\ .RE .\} .sp .sp Note that trailers do not follow (nor are they intended to follow) many of the rules for RFC 822 headers\&. For example they do not follow the encoding rule\&. .SH "OPTIONS" .PP \-\-in\-place .RS 4 Edit the files in place\&. .RE .PP \-\-trim\-empty .RS 4 If the part of any trailer contains only whitespace, the whole trailer will be removed from the output\&. This applies to existing trailers as well as new trailers\&. .RE .PP \-\-trailer [(=|:)] .RS 4 Specify a (, ) pair that should be applied as a trailer to the inputs\&. See the description of this command\&. .RE .PP \-\-where , \-\-no\-where .RS 4 Specify where all new trailers will be added\&. A setting provided with \fI\-\-where\fR overrides the \fBtrailer\&.where\fR and any applicable \fBtrailer\&.\&.where\fR configuration variables and applies to all \fI\-\-trailer\fR options until the next occurrence of \fI\-\-where\fR or \fI\-\-no\-where\fR\&. Upon encountering \fI\-\-no\-where\fR, clear the effect of any previous use of \fI\-\-where\fR, such that the relevant configuration variables are no longer overridden\&. Possible placements are \fBafter\fR, \fBbefore\fR, \fBend\fR or \fBstart\fR\&. .RE .PP \-\-if\-exists , \-\-no\-if\-exists .RS 4 Specify what action will be performed when there is already at least one trailer with the same in the input\&. A setting provided with \fI\-\-if\-exists\fR overrides the \fBtrailer\&.ifExists\fR and any applicable \fBtrailer\&.\&.ifExists\fR configuration variables and applies to all \fI\-\-trailer\fR options until the next occurrence of \fI\-\-if\-exists\fR or \fI\-\-no\-if\-exists\fR\&. Upon encountering \*(Aq\-\-no\-if\-exists, clear the effect of any previous use of \*(Aq\-\-if\-exists, such that the relevant configuration variables are no longer overridden\&. Possible actions are \fBaddIfDifferent\fR, \fBaddIfDifferentNeighbor\fR, \fBadd\fR, \fBreplace\fR and \fBdoNothing\fR\&. .RE .PP \-\-if\-missing , \-\-no\-if\-missing .RS 4 Specify what action will be performed when there is no other trailer with the same in the input\&. A setting provided with \fI\-\-if\-missing\fR overrides the \fBtrailer\&.ifMissing\fR and any applicable \fBtrailer\&.\&.ifMissing\fR configuration variables and applies to all \fI\-\-trailer\fR options until the next occurrence of \fI\-\-if\-missing\fR or \fI\-\-no\-if\-missing\fR\&. Upon encountering \*(Aq\-\-no\-if\-missing, clear the effect of any previous use of \*(Aq\-\-if\-missing, such that the relevant configuration variables are no longer overridden\&. Possible actions are \fBdoNothing\fR or \fBadd\fR\&. .RE .PP \-\-only\-trailers .RS 4 Output only the trailers, not any other parts of the input\&. .RE .PP \-\-only\-input .RS 4 Output only trailers that exist in the input; do not add any from the command\-line or by applying \fBtrailer\&.*\fR configuration variables\&. .RE .PP \-\-unfold .RS 4 If a trailer has a value that runs over multiple lines (aka "folded"), reformat the value into a single line\&. .RE .PP \-\-parse .RS 4 A convenience alias for \fB\-\-only\-trailers \-\-only\-input \-\-unfold\fR\&. This makes it easier to only see the trailers coming from the input without influencing them with any command line options or configuration variables, while also making the output machine\-friendly with \-\-unfold\&. .RE .PP \-\-no\-divider .RS 4 Do not treat \fB\-\-\-\fR as the end of the commit message\&. Use this when you know your input contains just the commit message itself (and not an email or the output of \fBgit format\-patch\fR)\&. .RE .SH "CONFIGURATION VARIABLES" .PP trailer\&.separators .RS 4 This option tells which characters are recognized as trailer separators\&. By default only \fI:\fR is recognized as a trailer separator, except that \fI=\fR is always accepted on the command line for compatibility with other git commands\&. .sp The first character given by this option will be the default character used when another separator is not specified in the config for this trailer\&. .sp For example, if the value for this option is "%=$", then only lines using the format \fI\fR with containing \fI%\fR, \fI=\fR or \fI$\fR and then spaces will be considered trailers\&. And \fI%\fR will be the default separator used, so by default trailers will appear like: \fI% \fR (one percent sign and one space will appear between the key and the value)\&. .RE .PP trailer\&.where .RS 4 This option tells where a new trailer will be added\&. .sp This can be \fBend\fR, which is the default, \fBstart\fR, \fBafter\fR or \fBbefore\fR\&. .sp If it is \fBend\fR, then each new trailer will appear at the end of the existing trailers\&. .sp If it is \fBstart\fR, then each new trailer will appear at the start, instead of the end, of the existing trailers\&. .sp If it is \fBafter\fR, then each new trailer will appear just after the last trailer with the same \&. .sp If it is \fBbefore\fR, then each new trailer will appear just before the first trailer with the same \&. .RE .PP trailer\&.ifexists .RS 4 This option makes it possible to choose what action will be performed when there is already at least one trailer with the same in the input\&. .sp The valid values for this option are: \fBaddIfDifferentNeighbor\fR (this is the default), \fBaddIfDifferent\fR, \fBadd\fR, \fBreplace\fR or \fBdoNothing\fR\&. .sp With \fBaddIfDifferentNeighbor\fR, a new trailer will be added only if no trailer with the same (, ) pair is above or below the line where the new trailer will be added\&. .sp With \fBaddIfDifferent\fR, a new trailer will be added only if no trailer with the same (, ) pair is already in the input\&. .sp With \fBadd\fR, a new trailer will be added, even if some trailers with the same (, ) pair are already in the input\&. .sp With \fBreplace\fR, an existing trailer with the same will be deleted and the new trailer will be added\&. The deleted trailer will be the closest one (with the same ) to the place where the new one will be added\&. .sp With \fBdoNothing\fR, nothing will be done; that is no new trailer will be added if there is already one with the same in the input\&. .RE .PP trailer\&.ifmissing .RS 4 This option makes it possible to choose what action will be performed when there is not yet any trailer with the same in the input\&. .sp The valid values for this option are: \fBadd\fR (this is the default) and \fBdoNothing\fR\&. .sp With \fBadd\fR, a new trailer will be added\&. .sp With \fBdoNothing\fR, nothing will be done\&. .RE .PP trailer\&.\&.key .RS 4 Defines a for the \&. The must be a prefix (case does not matter) of the \&. For example, in \fBgit config trailer\&.ack\&.key "Acked\-by"\fR the "Acked\-by" is the and the "ack" is the \&. This configuration allows the shorter \fB\-\-trailer "ack:\&.\&.\&."\fR invocation on the command line using the "ack" instead of the longer \fB\-\-trailer "Acked\-by:\&.\&.\&."\fR\&. .sp At the end of the , a separator can appear and then some space characters\&. By default the only valid separator is \fI:\fR, but this can be changed using the \fBtrailer\&.separators\fR config variable\&. .sp If there is a separator in the key, then it overrides the default separator when adding the trailer\&. .RE .PP trailer\&.\&.where .RS 4 This option takes the same values as the \fItrailer\&.where\fR configuration variable and it overrides what is specified by that option for trailers with the specified \&. .RE .PP trailer\&.\&.ifexists .RS 4 This option takes the same values as the \fItrailer\&.ifexists\fR configuration variable and it overrides what is specified by that option for trailers with the specified \&. .RE .PP trailer\&.\&.ifmissing .RS 4 This option takes the same values as the \fItrailer\&.ifmissing\fR configuration variable and it overrides what is specified by that option for trailers with the specified \&. .RE .PP trailer\&.\&.command .RS 4 Deprecated in favor of \fItrailer\&.\&.cmd\fR\&. This option behaves in the same way as \fItrailer\&.\&.cmd\fR, except that it doesn\(cqt pass anything as argument to the specified command\&. Instead the first occurrence of substring $ARG is replaced by the that would be passed as argument\&. .sp Note that $ARG in the user\(cqs command is only replaced once and that the original way of replacing $ARG is not safe\&. .sp When both \fItrailer\&.\&.cmd\fR and \fItrailer\&.\&.command\fR are given for the same , \fItrailer\&.\&.cmd\fR is used and \fItrailer\&.\&.command\fR is ignored\&. .RE .PP trailer\&.\&.cmd .RS 4 This option can be used to specify a shell command that will be called once to automatically add a trailer with the specified , and then called each time a \fI\-\-trailer =\fR argument is specified to modify the of the trailer that this option would produce\&. .sp When the specified command is first called to add a trailer with the specified , the behavior is as if a special \fI\-\-trailer =\fR argument was added at the beginning of the "git interpret\-trailers" command, where is taken to be the standard output of the command with any leading and trailing whitespace trimmed off\&. .sp If some \fI\-\-trailer =\fR arguments are also passed on the command line, the command is called again once for each of these arguments with the same \&. And the part of these arguments, if any, will be passed to the command as its first argument\&. This way the command can produce a computed from the passed in the \fI\-\-trailer =\fR argument\&. .RE .SH "EXAMPLES" .sp .RS 4 .ie n \{\ \h'-04'\(bu\h'+03'\c .\} .el \{\ .sp -1 .IP \(bu 2.3 .\} Configure a \fIsign\fR trailer with a \fISigned\-off\-by\fR key, and then add two of these trailers to a commit message file: .sp .if n \{\ .RS 4 .\} .nf $ git config trailer\&.sign\&.key "Signed\-off\-by" $ cat msg\&.txt subject body text $ git interpret\-trailers \-\-trailer \*(Aqsign: Alice \*(Aq \-\-trailer \*(Aqsign: Bob \*(Aq Signed\-off\-by: Bob .fi .if n \{\ .RE .\} .sp .RE .sp .RS 4 .ie n \{\ \h'-04'\(bu\h'+03'\c .\} .el \{\ .sp -1 .IP \(bu 2.3 .\} Use the \fB\-\-in\-place\fR option to edit a commit message file in place: .sp .if n \{\ .RS 4 .\} .nf $ cat msg\&.txt subject body text Signed\-off\-by: Bob $ git interpret\-trailers \-\-trailer \*(AqAcked\-by: Alice \*(Aq \-\-in\-place msg\&.txt $ cat msg\&.txt subject body text Signed\-off\-by: Bob Acked\-by: Alice .fi .if n \{\ .RE .\} .sp .RE .sp .RS 4 .ie n \{\ \h'-04'\(bu\h'+03'\c .\} .el \{\ .sp -1 .IP \(bu 2.3 .\} Extract the last commit as a patch, and add a \fICc\fR and a \fIReviewed\-by\fR trailer to it: .sp .if n \{\ .RS 4 .\} .nf $ git format\-patch \-1 0001\-foo\&.patch $ git interpret\-trailers \-\-trailer \*(AqCc: Alice \*(Aq \-\-trailer \*(AqReviewed\-by: Bob \*(Aq 0001\-foo\&.patch >0001\-bar\&.patch .fi .if n \{\ .RE .\} .sp .RE .sp .RS 4 .ie n \{\ \h'-04'\(bu\h'+03'\c .\} .el \{\ .sp -1 .IP \(bu 2.3 .\} Configure a \fIsign\fR trailer with a command to automatically add a \*(AqSigned\-off\-by: \*(Aq with the author information only if there is no \*(AqSigned\-off\-by: \*(Aq already, and show how it works: .sp .if n \{\ .RS 4 .\} .nf $ cat msg1\&.txt subject body text $ git config trailer\&.sign\&.key "Signed\-off\-by: " $ git config trailer\&.sign\&.ifmissing add $ git config trailer\&.sign\&.ifexists doNothing $ git config trailer\&.sign\&.cmd \*(Aqecho "$(git config user\&.name) <$(git config user\&.email)>"\*(Aq $ git interpret\-trailers \-\-trailer sign $ cat msg2\&.txt subject body text Signed\-off\-by: Alice $ git interpret\-trailers \-\-trailer sign .fi .if n \{\ .RE .\} .sp .RE .sp .RS 4 .ie n \{\ \h'-04'\(bu\h'+03'\c .\} .el \{\ .sp -1 .IP \(bu 2.3 .\} Configure a \fIfix\fR trailer with a key that contains a \fI#\fR and no space after this character, and show how it works: .sp .if n \{\ .RS 4 .\} .nf $ git config trailer\&.separators ":#" $ git config trailer\&.fix\&.key "Fix #" $ echo "subject" | git interpret\-trailers \-\-trailer fix=42 subject Fix #42 .fi .if n \{\ .RE .\} .sp .RE .sp .RS 4 .ie n \{\ \h'-04'\(bu\h'+03'\c .\} .el \{\ .sp -1 .IP \(bu 2.3 .\} Configure a \fIhelp\fR trailer with a cmd use a script \fBglog\-find\-author\fR which search specified author identity from git log in git repository and show how it works: .sp .if n \{\ .RS 4 .\} .nf $ cat ~/bin/glog\-find\-author #!/bin/sh test \-n "$1" && git log \-\-author="$1" \-\-pretty="%an <%ae>" \-1 || true $ cat msg\&.txt subject body text $ git config trailer\&.help\&.key "Helped\-by: " $ git config trailer\&.help\&.ifExists "addIfDifferentNeighbor" $ git config trailer\&.help\&.cmd "~/bin/glog\-find\-author" $ git interpret\-trailers \-\-trailer="help:Junio" \-\-trailer="help:Couder" Helped\-by: Christian Couder .fi .if n \{\ .RE .\} .sp .RE .sp .RS 4 .ie n \{\ \h'-04'\(bu\h'+03'\c .\} .el \{\ .sp -1 .IP \(bu 2.3 .\} Configure a \fIref\fR trailer with a cmd use a script \fBglog\-grep\fR to grep last relevant commit from git log in the git repository and show how it works: .sp .if n \{\ .RS 4 .\} .nf $ cat ~/bin/glog\-grep #!/bin/sh test \-n "$1" && git log \-\-grep "$1" \-\-pretty=reference \-1 || true $ cat msg\&.txt subject body text $ git config trailer\&.ref\&.key "Reference\-to: " $ git config trailer\&.ref\&.ifExists "replace" $ git config trailer\&.ref\&.cmd "~/bin/glog\-grep" $ git interpret\-trailers \-\-trailer="ref:Add copyright notices\&." commit_template\&.txt $ git config commit\&.template commit_template\&.txt $ cat \&.git/hooks/commit\-msg #!/bin/sh git interpret\-trailers \-\-trim\-empty \-\-trailer "git\-version: \e$(git describe)" "\e$1" > "\e$1\&.new" mv "\e$1\&.new" "\e$1" $ chmod +x \&.git/hooks/commit\-msg .fi .if n \{\ .RE .\} .sp .RE .SH "SEE ALSO" .sp \fBgit-commit\fR(1), \fBgit-format-patch\fR(1), \fBgit-config\fR(1) .SH "GIT" .sp Part of the \fBgit\fR(1) suite