GIT-REV-PARSE(1) Git Manual GIT-REV-PARSE(1)
NAME
git-rev-parse - Pick out and massage parameters
SYNOPSIS
git rev-parse [ option ] ...
DESCRIPTION
Many Git porcelainish commands take mixture of flags (i.e. parameters
that begin with a dash -) and parameters meant for the underlying git
rev-list command they use internally and flags and parameters for the
other commands they use downstream of git rev-list. This command is
used to distinguish between them.
OPTIONS
parseopt
Use git rev-parse in option parsing mode (see PARSEOPT section
below).
keep-dashdash
Only meaningful in parseopt mode. Tells the option parser to echo
out the first met instead of skipping it.
stop-at-non-option
Only meaningful in parseopt mode. Lets the option parser stop at
the first non-option argument. This can be used to parse
sub-commands that take options themselves.
sq-quote
Use git rev-parse in shell quoting mode (see SQ-QUOTE section
below). In contrast to the sq option below, this mode does only
quoting. Nothing else is done to command input.
revs-only
Do not output flags and parameters not meant for git rev-list
command.
no-revs
Do not output flags and parameters meant for git rev-list command.
flags
Do not output non-flag parameters.
no-flags
Do not output flag parameters.
default
If there is no parameter given by the user, use instead.
verify
Verify that exactly one parameter is provided, and that it can be
turned into a raw 20-byte SHA-1 that can be used to access the
object database. If so, emit it to the standard output; otherwise,
error out.
If you want to make sure that the output actually names an object
in your object database and/or can be used as a specific type of
object For example, git rev-parse "$VAR^{commit}" will make sure
$VAR names an existing object that is a commit-ish (i.e. a commit,
or an annotated tag that points at a commit). To make sure that
$VAR names an existing object of any type, git rev-parse
"$VAR^{object}" can be used.
-q, quiet
Only meaningful in verify mode. Do not output an error message if
the first argument is not a valid object name; instead exit with
non-zero status silently.
sq
Usually the output is made one line per flag and parameter. This
option makes output a single line, properly quoted for consumption
by shell. Useful when you expect your parameter to contain
whitespaces and newlines (e.g. when using pickaxe -S with git
diff-*). In contrast to the sq-quote option, the command input is
still interpreted as usual.
not
When showing object names, prefix them with ^ and strip ^ prefix
from the object names that already have one.
symbolic
Usually the object names are output in SHA-1 form (with possible ^
prefix); this option makes them output in a form as close to the
original input as possible.
symbolic-full-name
This is similar to symbolic, but it omits input that are not refs
(i.e. branch or tag names; or more explicitly disambiguating
"heads/master" form, when you want to name the "master" branch when
there is an unfortunately named tag "master"), and show them as
full refnames (e.g. "refs/heads/master").
abbrev-ref[=(strict|loose)]
A non-ambiguous short name of the objects name. The option
core.warnAmbiguousRefs is used to select the strict abbreviation
mode.
disambiguate=
Show every object whose name begins with the given prefix. The
must be at least 4 hexadecimal digits long to avoid
listing each and every object in the repository by mistake.
all
Show all refs found in refs/.
branches[=pattern], tags[=pattern], remotes[=pattern]
Show all branches, tags, or remote-tracking branches, respectively
(i.e., refs found in refs/heads, refs/tags, or refs/remotes,
respectively).
If a pattern is given, only refs matching the given shell glob are
shown. If the pattern does not contain a globbing character (?, *,
or [), it is turned into a prefix match by appending /*.
glob=pattern
Show all refs matching the shell glob pattern pattern. If the
pattern does not start with refs/, this is automatically prepended.
If the pattern does not contain a globbing character (?, *, or [),
it is turned into a prefix match by appending /*.
show-toplevel
Show the absolute path of the top-level directory.
show-prefix
When the command is invoked from a subdirectory, show the path of
the current directory relative to the top-level directory.
show-cdup
When the command is invoked from a subdirectory, show the path of
the top-level directory relative to the current directory
(typically a sequence of "../", or an empty string).
git-dir
Show $GITDIR if defined. Otherwise show the path to the .git
directory. The path shown, when relative, is relative to the
current working directory.
If $GITDIR is not defined and the current directory is not
detected to lie in a Git repository or work tree print a message to
stderr and exit with nonzero status.
is-inside-git-dir
When the current working directory is below the repository
directory print "true", otherwise "false".
is-inside-work-tree
When the current working directory is inside the work tree of the
repository print "true", otherwise "false".
is-bare-repository
When the repository is bare print "true", otherwise "false".
local-env-vars
List the GIT* environment variables that are local to the
repository (e.g. GITDIR or GITWORKTREE, but not GITEDITOR).
Only the names of the variables are listed, not their value, even
if they are set.
short, short=number
Instead of outputting the full SHA-1 values of object names try to
abbreviate them to a shorter unique name. When no length is
specified 7 is used. The minimum length is 4.
since=datestring, after=datestring
Parse the date string, and output the corresponding max-age=
parameter for git rev-list.
until=datestring, before=datestring
Parse the date string, and output the corresponding min-age=
parameter for git rev-list.
...
Flags and parameters to be parsed.
resolve-git-dir
Check if is a valid repository or a gitfile that points at a
valid repository, and print the location of the repository. If
is a gitfile then the resolved path to the real repository
is printed.
SPECIFYING REVISIONS
A revision parameter typically, but not necessarily, names a
commit object. It uses what is called an extended SHA-1 syntax. Here
are various ways to spell object names. The ones listed near the end of
this list name trees and blobs contained in a commit.
, e.g. dae86e1950b1277e545cee180551750029cfe735, dae86e
The full SHA-1 object name (40-byte hexadecimal string), or a
leading substring that is unique within the repository. E.g.
dae86e1950b1277e545cee180551750029cfe735 and dae86e both name the
same commit object if there is no other object in your repository
whose object name starts with dae86e.
, e.g. v1.7.4.2-679-g3bee7fb
Output from git describe; i.e. a closest tag, optionally followed
by a dash and a number of commits, followed by a dash, a g, and an
abbreviated object name.
, e.g. master, heads/master, refs/heads/master
A symbolic ref name. E.g. master typically means the commit object
referenced by refs/heads/master. If you happen to have both
heads/master and tags/master, you can explicitly say heads/master
to tell Git which one you mean. When ambiguous, a is
disambiguated by taking the first match in the following rules:
1. If $GITDIR/ exists, that is what you mean (this is
usually useful only for HEAD, FETCHHEAD, ORIGHEAD, MERGEHEAD
and CHERRYPICKHEAD);
2. otherwise, refs/ if it exists;
3. otherwise, refs/tags/ if it exists;
4. otherwise, refs/heads/ if it exists;
5. otherwise, refs/remotes/ if it exists;
6. otherwise, refs/remotes//HEAD if it exists.
HEAD names the commit on which you based the changes in the
working tree. FETCHHEAD records the branch which you fetched
from a remote repository with your last git fetch invocation.
ORIGHEAD is created by commands that move your HEAD in a
drastic way, to record the position of the HEAD before their
operation, so that you can easily change the tip of the branch
back to the state before you ran them. MERGEHEAD records the
commit(s) which you are merging into your branch when you run
git merge. CHERRYPICKHEAD records the commit which you are
cherry-picking when you run git cherry-pick.
Note that any of the refs/* cases above may come either from
the $GITDIR/refs directory or from the $GITDIR/packed-refs
file. While the ref name encoding is unspecified, UTF-8 is
preferred as some output processing may assume ref names in
UTF-8.
@{}, e.g. master@{yesterday}, HEAD@{5 minutes ago}
A ref followed by the suffix @ with a date specification enclosed
in a brace pair (e.g. {yesterday}, {1 month 2 weeks 3 days 1 hour
1 second ago} or {1979-02-26 18:30:00}) specifies the value of the
ref at a prior point in time. This suffix may only be used
immediately following a ref name and the ref must have an existing
log ($GITDIR/logs/[). Note that this looks up the state of
your local ref at a given time; e.g., what was in your local master
branch last week. If you want to look at commits made during
certain times, see since and until.
@{}, e.g. master@{1}
A ref followed by the suffix @ with an ordinal specification
] enclosed in a brace pair (e.g. {1}, {15}) specifies the n-th prior
value of that ref. For example master@{1} is the immediate prior
value of master while master@{5} is the 5th prior value of master.
This suffix may only be used immediately following a ref name and
the ref must have an existing log ($GITDIR/logs/).
@{}, e.g. @{1}
You can use the @ construct with an empty ref part to get at a
reflog entry of the current branch. For example, if you are on
branch blabla then @{1} means the same as blabla@{1}.
@{-}, e.g. @{-1}
The construct @{-} means the th branch checked out before the
current one.
@{upstream}, e.g. master@{upstream}, @{u}
The suffix @{upstream} to a branchname (short form
@{u}) refers to the branch that the branch specified by
branchname is set to build on top of. A missing branchname defaults
to the current one.
^, e.g. HEAD^, v1.5.1^0
A suffix ^ to a revision parameter means the first parent of that
commit object. ^ means the th parent (i.e. ^ is
equivalent to ^1). As a special rule, ^0 means the commit
itself and is used when is the object name of a tag object
that refers to a commit object.
~, e.g. master~3
A suffix ~ to a revision parameter means the commit object that
is the th generation ancestor of the named commit object,
following only the first parents. I.e. ~3 is equivalent to
^^^ which is equivalent to ^1^1^1. See below for an
illustration of the usage of this form.
^{}, e.g. v0.99.8^{commit}
A suffix ^ followed by an object type name enclosed in brace pair
means the object could be a tag, and dereference the tag
recursively until an object of that type is found or the object
cannot be dereferenced anymore (in which case, barf). ^0 is a
short-hand for ^{commit}.
rev^{object} can be used to make sure rev names an object that
exists, without requiring rev to be a tag, and without
dereferencing rev; because a tag is already an object, it does not
have to be dereferenced even once to get to an object.
^{}, e.g. v0.99.8^{}
A suffix ^ followed by an empty brace pair means the object could
be a tag, and dereference the tag recursively until a non-tag
object is found.
^{/}, e.g. HEAD^{/fix nasty bug}
A suffix ^ to a revision parameter, followed by a brace pair that
contains a text led by a slash, is the same as the :/fix nasty bug
syntax below except that it returns the youngest matching commit
which is reachable from the before ^.
:/, e.g. :/fix nasty bug
A colon, followed by a slash, followed by a text, names a commit
whose commit message matches the specified regular expression. This
name returns the youngest matching commit which is reachable from
any ref. If the commit message starts with a ! you have to repeat
that; the special sequence :/!, followed by something else than !,
is reserved for now. The regular expression can match any part of
the commit message. To match messages starting with a string, one
can use e.g. :/^foo.
:, e.g. HEAD:README, :README, master:./README
A suffix : followed by a path names the blob or tree at the given
path in the tree-ish object named by the part before the colon.
:path (with an empty part before the colon) is a special case of
the syntax described next: content recorded in the index at the
given path. A path starting with ./ or ../ is relative to the
current working directory. The given path will be converted to be
relative to the working tree’s root directory. This is most useful
to address a blob or tree from a commit or tree that has the same
tree structure as the working tree.
::, e.g. :0:README, :README
A colon, optionally followed by a stage number (0 to 3) and a
colon, followed by a path, names a blob object in the index at the
given path. A missing stage number (and the colon that follows it)
names a stage 0 entry. During a merge, stage 1 is the common
ancestor, stage 2 is the target branch’s version (typically the
current branch), and stage 3 is the version from the branch which
is being merged.
Here is an illustration, by Jon Loeliger. Both commit nodes B and C are
parents of commit node A. Parent commits are ordered left-to-right.
G H I J
\ / \ /
D E F
\ | / \
\ | / |
\|/ |
B C
\ /
\ /
A
A = = A^0
B = A^ = A^1 = A~1
C = A^2 = A^2
D = A^^ = A^1^1 = A~2
E = B^2 = A^^2
F = B^3 = A^^3
G = A^^^ = A^1^1^1 = A~3
H = D^2 = B^^2 = A^^^2 = A~2^2
I = F^ = B^3^ = A^^3^
J = F^2 = B^3^2 = A^^3^2
SPECIFYING RANGES
History traversing commands such as git log operate on a set of
commits, not just a single commit. To these commands, specifying a
single revision with the notation described in the previous section
means the set of commits reachable from that commit, following the
commit ancestry chain.
To exclude commits reachable from a commit, a prefix ^ notation is
used. E.g. ^r1 r2 means commits reachable from r2 but exclude the ones
reachable from r1.
This set operation appears so often that there is a shorthand for it.
When you have two commits r1 and r2 (named according to the syntax
explained in SPECIFYING REVISIONS above), you can ask for commits that
are reachable from r2 excluding those that are reachable from r1 by ^r1
r2 and it can be written as r1..r2.
A similar notation r1...r2 is called symmetric difference of r1 and r2
and is defined as r1 r2 not $(git merge-base all r1 r2). It is the
set of commits that are reachable from either one of r1 or r2 but not
from both.
In these two shorthands, you can omit one end and let it default to
HEAD. For example, origin.. is a shorthand for origin..HEAD and asks
"What did I do since I forked from the origin branch?" Similarly,
..origin is a shorthand for HEAD..origin and asks "What did the origin
do since I forked from them?" Note that .. would mean HEAD..HEAD which
is an empty range that is both reachable and unreachable from HEAD.
Two other shorthands for naming a set that is formed by a commit and
its parent commits exist. The r1^@ notation means all parents of r1.
r1^! includes commit r1 but excludes all of its parents.
To summarize:
Include commits that are reachable from (i.e. ancestors of) .
^
Exclude commits that are reachable from (i.e. ancestors of) .
..
Include commits that are reachable from but exclude those
that are reachable from . When either or is
omitted, it defaults to HEAD.
...
Include commits that are reachable from either or but
exclude those that are reachable from both. When either or
is omitted, it defaults to HEAD.
^@, e.g. HEAD^@
A suffix ^ followed by an at sign is the same as listing all
parents of (meaning, include anything reachable from its
parents, but not the commit itself).
^!, e.g. HEAD^!
A suffix ^ followed by an exclamation mark is the same as giving
commit and then all its parents prefixed with ^ to exclude
them (and their ancestors).
Here are a handful of examples:
D G H D
D F G H I J D F
^G D H D
^D B E I J F B
B..C C
B...C G H D E B C
^D B C E I J F B C
C I J F C
C^@ I J F
C^! C
F^! D G H D F
PARSEOPT
In parseopt mode, git rev-parse helps massaging options to bring to
shell scripts the same facilities C builtins have. It works as an
option normalizer (e.g. splits single switches aggregate values), a bit
like getopt(1) does.
It takes on the standard input the specification of the options to
parse and understand, and echoes on the standard output a string
suitable for sh(1) eval to replace the arguments with normalized ones.
In case of error, it outputs usage on the standard error stream, and
exits with code 129.
Note: Make sure you quote the result when passing it to eval. See below
for an example.
Input Format
git rev-parse parseopt input format is fully text based. It has two
parts, separated by a line that contains only . The lines before the
separator (should be more than one) are used for the usage. The lines
after the separator describe the options.
Each line of options has this format:
* SP+ help LF
its format is the short option character, then the long option name
separated by a comma. Both parts are not required, though at least
one is necessary. h,help, dry-run and f are all three correct
.
are of *, =, ? or !.
· Use = if the option takes an argument.
· Use ? to mean that the option is optional (though its use is
discouraged).
· Use * to mean that this option should not be listed in the
usage generated for the -h argument. It’s shown for help-all
as documented in gitcli(7).
· Use ! to not make the corresponding negated long option
available.
The remainder of the line, after stripping the spaces, is used as the
help associated to the option.
Blank lines are ignored, and lines that don’t match this specification
are used as option group headers (start the line with a space to create
such lines on purpose).
Example
OPTSSPEC="\
some-command [options] ...
some-command does foo and bar!
h,help show the help
foo some nifty option foo
bar= some cool option bar with an argument
An option group Header
C? option C with an optional argument"
eval "$(echo "$OPTSSPEC" | git rev-parse parseopt "$@" || echo exit $?)"
SQ-QUOTE
In sq-quote mode, git rev-parse echoes on the standard output a
single line suitable for sh(1) eval. This line is made by normalizing
the arguments following sq-quote. Nothing other than quoting the
arguments is done.
If you want command input to still be interpreted as usual by git
rev-parse before the output is shell quoted, see the sq option.
Example
$ cat >your-git-script.sh <<\EOF
#!/bin/sh
args=$(git rev-parse sq-quote "$@") # quote user-supplied arguments
command="git frotz -n24 $args" # and use it inside a handcrafted
# command line
eval "$command"
EOF
$ sh your-git-script.sh "a b'c"
EXAMPLES
· Print the object name of the current commit:
$ git rev-parse verify HEAD
· Print the commit object name from the revision in the $REV shell
variable:
$ git rev-parse verify $REV^{commit}
This will error out if $REV is empty or not a valid revision.
· Similar to above:
$ git rev-parse default master verify $REV
but if $REV is empty, the commit object name from master will be
printed.
GIT
Part of the git(1) suite
Git 1.8.3.1 11/02/2018 GIT-REV-PARSE(1)