Documentation / git-describe.txton commit Merge branch 'sh/rebase-i-p' (7ff866e)
   1git-describe(1)
   2===============
   3
   4NAME
   5----
   6git-describe - Show the most recent tag that is reachable from a commit
   7
   8
   9SYNOPSIS
  10--------
  11'git describe' [--all] [--tags] [--contains] [--abbrev=<n>] <committish>...
  12
  13DESCRIPTION
  14-----------
  15The command finds the most recent tag that is reachable from a
  16commit.  If the tag points to the commit, then only the tag is
  17shown.  Otherwise, it suffixes the tag name with the number of
  18additional commits on top of the tagged object and the
  19abbreviated object name of the most recent commit.
  20
  21By default (without --all or --tags) `git describe` only shows
  22annotated tags.  For more information about creating annotated tags
  23see the -a and -s options to linkgit:git-tag[1].
  24
  25OPTIONS
  26-------
  27<committish>...::
  28        Committish object names to describe.
  29
  30--all::
  31        Instead of using only the annotated tags, use any ref
  32        found in `.git/refs/`.  This option enables matching
  33        any known branch, remote branch, or lightweight tag.
  34
  35--tags::
  36        Instead of using only the annotated tags, use any tag
  37        found in `.git/refs/tags`.  This option enables matching
  38        a lightweight (non-annotated) tag.
  39
  40--contains::
  41        Instead of finding the tag that predates the commit, find
  42        the tag that comes after the commit, and thus contains it.
  43        Automatically implies --tags.
  44
  45--abbrev=<n>::
  46        Instead of using the default 8 hexadecimal digits as the
  47        abbreviated object name, use <n> digits.
  48
  49--candidates=<n>::
  50        Instead of considering only the 10 most recent tags as
  51        candidates to describe the input committish consider
  52        up to <n> candidates.  Increasing <n> above 10 will take
  53        slightly longer but may produce a more accurate result.
  54        An <n> of 0 will cause only exact matches to be output.
  55
  56--exact-match::
  57        Only output exact matches (a tag directly references the
  58        supplied commit).  This is a synonym for --candidates=0.
  59
  60--debug::
  61        Verbosely display information about the searching strategy
  62        being employed to standard error.  The tag name will still
  63        be printed to standard out.
  64
  65--long::
  66        Always output the long format (the tag, the number of commits
  67        and the abbreviated commit name) even when it matches a tag.
  68        This is useful when you want to see parts of the commit object name
  69        in "describe" output, even when the commit in question happens to be
  70        a tagged version.  Instead of just emitting the tag name, it will
  71        describe such a commit as v1.2-0-deadbeef (0th commit since tag v1.2
  72        that points at object deadbeef....).
  73
  74--match <pattern>::
  75        Only consider tags matching the given pattern (can be used to avoid
  76        leaking private tags made from the repository).
  77
  78--always::
  79        Show uniquely abbreviated commit object as fallback.
  80
  81EXAMPLES
  82--------
  83
  84With something like git.git current tree, I get:
  85
  86        [torvalds@g5 git]$ git describe parent
  87        v1.0.4-14-g2414721
  88
  89i.e. the current head of my "parent" branch is based on v1.0.4,
  90but since it has a handful commits on top of that,
  91describe has added the number of additional commits ("14") and
  92an abbreviated object name for the commit itself ("2414721")
  93at the end.
  94
  95The number of additional commits is the number
  96of commits which would be displayed by "git log v1.0.4..parent".
  97The hash suffix is "-g" + 7-char abbreviation for the tip commit
  98of parent (which was `2414721b194453f058079d897d13c4e377f92dc6`).
  99
 100Doing a 'git-describe' on a tag-name will just show the tag name:
 101
 102        [torvalds@g5 git]$ git describe v1.0.4
 103        v1.0.4
 104
 105With --all, the command can use branch heads as references, so
 106the output shows the reference path as well:
 107
 108        [torvalds@g5 git]$ git describe --all --abbrev=4 v1.0.5^2
 109        tags/v1.0.0-21-g975b
 110
 111        [torvalds@g5 git]$ git describe --all HEAD^
 112        heads/lt/describe-7-g975b
 113
 114With --abbrev set to 0, the command can be used to find the
 115closest tagname without any suffix:
 116
 117        [torvalds@g5 git]$ git describe --abbrev=0 v1.0.5^2
 118        tags/v1.0.0
 119
 120SEARCH STRATEGY
 121---------------
 122
 123For each committish supplied, 'git-describe' will first look for
 124a tag which tags exactly that commit.  Annotated tags will always
 125be preferred over lightweight tags, and tags with newer dates will
 126always be preferred over tags with older dates.  If an exact match
 127is found, its name will be output and searching will stop.
 128
 129If an exact match was not found, 'git-describe' will walk back
 130through the commit history to locate an ancestor commit which
 131has been tagged.  The ancestor's tag will be output along with an
 132abbreviation of the input committish's SHA1.
 133
 134If multiple tags were found during the walk then the tag which
 135has the fewest commits different from the input committish will be
 136selected and output.  Here fewest commits different is defined as
 137the number of commits which would be shown by `git log tag..input`
 138will be the smallest number of commits possible.
 139
 140
 141Author
 142------
 143Written by Linus Torvalds <torvalds@osdl.org>, but somewhat
 144butchered by Junio C Hamano <gitster@pobox.com>.  Later significantly
 145updated by Shawn Pearce <spearce@spearce.org>.
 146
 147Documentation
 148--------------
 149Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
 150
 151GIT
 152---
 153Part of the linkgit:git[1] suite