gitrevisions - specifying revisions and ranges for Git




   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

       @ 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.

   <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

       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}

           $ git rev-parse --symbolic-full-name @{push}

       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.

   <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^{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

   <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^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
   Two 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.

   While <rev>^<n> was about specifying a single commit parent, these two
   notations consider all its parents. For example you can say HEAD^2^@,
   however you cannot say HEAD^@^2.


       Include commits that are reachable from <rev> (i.e. <rev> and its

       Exclude commits that are reachable from <rev> (i.e. <rev> and its

       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.

       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).

   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
       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




   Part of the git(1) suite


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