# gitrevisions

## 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** , **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
    


## 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 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



           Part of the git(1) suite
    


* * *