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NAME | SYNOPSIS | DESCRIPTION | SPECIFYING REVISIONS | SPECIFYING RANGES | REVISION RANGE SUMMARY | SEE ALSO | GIT | COLOPHON |
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GITREVISIONS(7) Git Manual GITREVISIONS(7)
gitrevisions - Specifying revisions and ranges for Git
gitrevisions
Many Git commands take revision parameters as arguments.
Depending on the command, they denote a specific commit or, for
commands which walk the revision graph (such as git-log(1)), all
commits which are reachable from that commit. For commands that
walk the revision graph one can also specify a range of revisions
explicitly.
In addition, some Git commands (such as git-show(1) and
git-push(1)) can also take revision parameters which denote other
objects than commits, e.g. blobs ("files") or trees ("directories
of files").
A revision parameter <rev> 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.
Note
This document shows the "raw" syntax as seen by git. The
shell and other UIs might require additional quoting to
protect special characters and to avoid word splitting.
<sha1>, 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.
<describeOutput>, 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.
<refname>, 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 <refname> is disambiguated by taking the first match in the
following rules:
1. If $GIT_DIR/<refname> exists, that is what you mean (this
is usually useful only for HEAD, FETCH_HEAD, ORIG_HEAD,
MERGE_HEAD, REBASE_HEAD, REVERT_HEAD, CHERRY_PICK_HEAD,
BISECT_HEAD and AUTO_MERGE);
2. otherwise, refs/<refname> if it exists;
3. otherwise, refs/tags/<refname> if it exists;
4. otherwise, refs/heads/<refname> if it exists;
5. otherwise, refs/remotes/<refname> if it exists;
6. otherwise, refs/remotes/<refname>/HEAD if it exists.
HEAD
names the commit on which you based the changes in the
working tree.
FETCH_HEAD
records the branch which you fetched from a remote
repository with your last git fetch invocation.
ORIG_HEAD
is created by commands that move your HEAD in a drastic
way (git am, git merge, git rebase, git reset), 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.
MERGE_HEAD
records the commit(s) which you are merging into your
branch when you run git merge.
REBASE_HEAD
during a rebase, records the commit at which the
operation is currently stopped, either because of
conflicts or an edit command in an interactive rebase.
REVERT_HEAD
records the commit which you are reverting when you run
git revert.
CHERRY_PICK_HEAD
records the commit which you are cherry-picking when you
run git cherry-pick.
BISECT_HEAD
records the current commit to be tested when you run git
bisect --no-checkout.
AUTO_MERGE
records a tree object corresponding to the state the ort
merge strategy wrote to the working tree when a merge
operation resulted in conflicts.
Note that any of the refs/* cases above may come either from
the $GIT_DIR/refs directory or from the $GIT_DIR/packed-refs
file. While the ref name encoding is unspecified, UTF-8 is
preferred as some output processing may assume ref names in
UTF-8.
@
@ alone is a shortcut for HEAD.
[<refname>]@{<date>}, e.g. master@{yesterday}, HEAD@{5 minutes
ago}
A ref followed by the suffix @ with a date specification
enclosed in a brace pair (e.g. {yesterday}, {1 month 2 weeks
3 days 1 hour 1 second ago} or {1979-02-26 18:30:00})
specifies the value of the ref at a prior point in time. This
suffix may only be used immediately following a ref name and
the ref must have an existing log ($GIT_DIR/logs/<ref>). 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.
<refname>@{<n>}, 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 ($GIT_DIR/logs/<refname>).
@{<n>}, 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}.
@{-<n>}, e.g. @{-1}
The construct @{-<n>} means the <n>th branch/commit checked
out before the current one.
[<branchname>]@{upstream}, e.g. master@{upstream}, @{u}
A branch B may be set up to build on top of a branch X
(configured with branch.<name>.merge) at a remote R
(configured with the branch X taken from remote R, typically
found at refs/remotes/R/X.
[<branchname>]@{push}, e.g. master@{push}, @{push}
The suffix @{push} reports the branch "where we would push
to" if git push were run while branchname was checked out (or
the current HEAD if no branchname is specified). Like for
@{upstream}, we report the remote-tracking branch that
corresponds to that branch at the remote.
Here’s an example to make it more clear:
$ git config push.default current
$ git config remote.pushdefault myfork
$ git switch -c mybranch origin/master
$ git rev-parse --symbolic-full-name @{upstream}
refs/remotes/origin/master
$ git rev-parse --symbolic-full-name @{push}
refs/remotes/myfork/mybranch
Note in the example that we set up a triangular workflow,
where we pull from one location and push to another. In a
non-triangular workflow, @{push} is the same as @{upstream},
and there is no need for it.
This suffix is also accepted when spelled in uppercase, and
means the same thing no matter the case.
<rev>^[<n>], e.g. HEAD^, v1.5.1^0
A suffix ^ to a revision parameter means the first parent of
that commit object. ^<n> means the <n>th parent (i.e.
<rev>^ is equivalent to <rev>^1). As a special rule, <rev>^0
means the commit itself and is used when <rev> is the object
name of a tag object that refers to a commit object.
<rev>~[<n>], e.g. HEAD~, master~3
A suffix ~ to a revision parameter means the first parent of
that commit object. A suffix ~<n> to a revision parameter
means the commit object that is the <n>th generation ancestor
of the named commit object, following only the first parents.
I.e. <rev>~3 is equivalent to <rev>^^^ which is equivalent
to <rev>^1^1^1. See below for an illustration of the usage of
this form.
<rev>^{<type>}, e.g. v0.99.8^{commit}
A suffix ^ followed by an object type name enclosed in brace
pair means dereference the object at <rev> recursively until
an object of type <type> is found or the object cannot be
dereferenced anymore (in which case, barf). For example, if
<rev> is a commit-ish, <rev>^{commit} describes the
corresponding commit object. Similarly, if <rev> is a
tree-ish, <rev>^{tree} describes the corresponding tree
object. <rev>^0 is a short-hand for <rev>^{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.
<rev>^{tag} can be used to ensure that <rev> identifies an
existing tag object.
<rev>^{}, 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.
<rev>^{/<text>}, 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 <rev> before ^.
:/<text>, 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, including HEAD. The regular
expression can match any part of the commit message. To match
messages starting with a string, one can use e.g. :/^foo.
The special sequence :/! is reserved for modifiers to what
is matched. :/!-foo performs a negative match, while :/!!foo
matches a literal ! character, followed by foo. Any other
sequence beginning with :/! is reserved for now. Depending
on the given text, the shell’s word splitting rules might
require additional quoting.
<rev>:<path>, e.g. HEAD: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. 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.
:[<n>:]<path>, 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
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
History traversing commands such as git log operate on a set of
commits, not just a single commit.
For these commands, specifying a single revision, using the
notation described in the previous section, means the set of
commits reachable from the given commit.
Specifying several revisions means the set of commits reachable
from any of the given commits.
A commit’s reachable set is the commit itself and the commits in
its ancestry chain.
There are several notations to specify a set of connected commits
(called a "revision range"), illustrated below.
Commit Exclusions
^<rev> (caret) Notation
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 (i.e. r1 and its
ancestors).
Dotted Range Notations
The .. (two-dot) Range Notation
The ^r1 r2 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.
The ... (three-dot) Symmetric Difference Notation
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 (left side) or r2 (right side) but not
from both.
In these two shorthand notations, 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.
Commands that are specifically designed to take two distinct
ranges (e.g. "git range-diff R1 R2" to compare two ranges) do
exist, but they are exceptions. Unless otherwise noted, all "git"
commands that operate on a set of commits work on a single
revision range. In other words, writing two "two-dot range
notation" next to each other, e.g.
$ git log A..B C..D
does not specify two revision ranges for most commands. Instead
it will name a single connected set of commits, i.e. those that
are reachable from either B or D but are reachable from neither A
or C. In a linear history like this:
---A---B---o---o---C---D
because A and B are reachable from C, the revision range
specified by these two dotted ranges is a single commit D.
Other <rev>^ Parent Shorthand Notations
Three other shorthands exist, particularly useful for merge
commits, for naming a set that is formed by a commit and its
parent commits.
The r1^@ notation means all parents of r1.
The r1^! notation includes commit r1 but excludes all of its
parents. By itself, this notation denotes the single commit r1.
The <rev>^-[<n>] notation includes <rev> but excludes the <n>th
parent (i.e. a shorthand for <rev>^<n>..<rev>), with <n> = 1 if
not given. This is typically useful for merge commits where you
can just pass <commit>^- to get all the commits in the branch
that was merged in merge commit <commit> (including <commit>
itself).
While <rev>^<n> was about specifying a single commit parent,
these three notations also consider its parents. For example you
can say HEAD^2^@, however you cannot say HEAD^@^2.
<rev>
Include commits that are reachable from <rev> (i.e. <rev> and
its ancestors).
^<rev>
Exclude commits that are reachable from <rev> (i.e. <rev> and
its ancestors).
<rev1>..<rev2>
Include commits that are reachable from <rev2> but exclude
those that are reachable from <rev1>. When either <rev1> or
<rev2> is omitted, it defaults to HEAD.
<rev1>...<rev2>
Include commits that are reachable from either <rev1> or
<rev2> but exclude those that are reachable from both. When
either <rev1> or <rev2> is omitted, it defaults to HEAD.
<rev>^@, e.g. HEAD^@
A suffix ^ followed by an at sign is the same as listing all
parents of <rev> (meaning, include anything reachable from
its parents, but not the commit itself).
<rev>^!, e.g. HEAD^!
A suffix ^ followed by an exclamation mark is the same as
giving commit <rev> and all its parents prefixed with ^ to
exclude them (and their ancestors).
<rev>^-<n>, e.g. HEAD^-, HEAD^-2
Equivalent to <rev>^<n>..<rev>, with <n> = 1 if not given.
Here are a handful of examples using the Loeliger illustration
above, with each step in the notation’s expansion and selection
carefully spelt out:
Args Expanded arguments Selected commits
D G H D
D F G H I J D F
^G D H D
^D B E I J F B
^D B C E I J F B C
C I J F C
B..C = ^B C C
B...C = B ^F C G H D E B C
B^- = B^..B
= ^B^1 B E I J F B
C^@ = C^1
= F I J F
B^@ = B^1 B^2 B^3
= D E F D G H E F I J
C^! = C ^C^@
= C ^C^1
= C ^F C
B^! = B ^B^@
= B ^B^1 ^B^2 ^B^3
= B ^D ^E ^F B
F^! D = F ^I ^J D G H D F
git-rev-parse(1)
Part of the git(1) suite
This page is part of the git (Git distributed version control
system) project. Information about the project can be found at
⟨http://git-scm.com/⟩. If you have a bug report for this manual
page, see ⟨http://git-scm.com/community⟩. This page was obtained
from the project's upstream Git repository
⟨https://github.com/git/git.git⟩ on 2024-06-14. (At that time,
the date of the most recent commit that was found in the
repository was 2024-06-12.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
man-pages@man7.org
Git 2.45.2.492.gd63586 2024-06-12 GITREVISIONS(7)
Pages that refer to this page: git(1), git-cat-file(1), git-check-ref-format(1), git-cherry-pick(1), git-config(1), git-diff(1), git-fast-import(1), git-format-patch(1), gitk(1), git-log(1), git-push(1), git-range-diff(1), git-rebase(1), git-reflog(1), git-revert(1), git-shortlog(1), git-show(1), git-show-branch(1), stg(1), gitcore-tutorial(7), gitglossary(7)
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HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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