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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)) 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.
<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 and CHERRY_PICK_HEAD);
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, 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. CHERRY_PICK_HEAD 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 $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}
The suffix @{upstream} to a branchname (short form
<branchname>@{u}) refers to the branch that the branch specified
by branchname is set to build on top of (configured with
branch.<name>.remote and branch.<name>.merge). A missing
branchname defaults to the current one. These suffixes are also
accepted when spelled in uppercase, and they mean the same thing
no matter the case.
<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). Since our push
destination is in a remote repository, of course, we report the
local tracking branch that corresponds to that branch (i.e.,
something in refs/remotes/).
Here’s an example to make it more clear:
$ git config push.default current
$ git config remote.pushdefault myfork
$ git checkout -b 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>^, 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. master~3
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. 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.
<rev>:<path>, 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.
:<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 = 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.
A commit’s reachable set is the commit itself and the commits in its
ancestry chain.
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.
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 then 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
2018-02-02. (At that time, the date of the most recent commit that
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(which is not part of the original manual page), send a mail to
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Git 2.16.1.2.g59c276cf 01/23/2018 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-reflog(1), git-revert(1), git-shortlog(1), git-show(1), git-show-branch(1), gitcore-tutorial(7), gitglossary(7)
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