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GITREVISIONS(7)			  Git Manual		       GITREVISIONS(7)



NAME
       gitrevisions - Specifying revisions and ranges for Git

SYNOPSIS
       gitrevisions

DESCRIPTION
       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").

SPECIFYING REVISIONS
       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
	       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}
	   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

SPECIFYING RANGES
       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.

REVISION RANGE SUMMARY
       <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

SEE ALSO
       git-rev-parse(1)

GIT
       Part of the git(1) suite



Git 2.38.4			  02/20/2023		       GITREVISIONS(7)