git-describe(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | SEARCH STRATEGY | BUGS | GIT | COLOPHON

GIT-DESCRIBE(1)                Git Manual                GIT-DESCRIBE(1)

NAME         top

       git-describe - Give an object a human readable name based on an
       available ref

SYNOPSIS         top

       git describe [--all] [--tags] [--contains] [--abbrev=<n>] [<commit-ish>...]
       git describe [--all] [--tags] [--contains] [--abbrev=<n>] --dirty[=<mark>]
       git describe <blob>

DESCRIPTION         top

       The command finds the most recent tag that is reachable from a
       commit. If the tag points to the commit, then only the tag is
       shown. Otherwise, it suffixes the tag name with the number of
       additional commits on top of the tagged object and the
       abbreviated object name of the most recent commit. The result is
       a "human-readable" object name which can also be used to identify
       the commit to other git commands.

       By default (without --all or --tags) git describe only shows
       annotated tags. For more information about creating annotated
       tags see the -a and -s options to git-tag(1).

       If the given object refers to a blob, it will be described as
       <commit-ish>:<path>, such that the blob can be found at <path> in
       the <commit-ish>, which itself describes the first commit in
       which this blob occurs in a reverse revision walk from HEAD.

OPTIONS         top

       <commit-ish>...
           Commit-ish object names to describe. Defaults to HEAD if
           omitted.

       --dirty[=<mark>], --broken[=<mark>]
           Describe the state of the working tree. When the working tree
           matches HEAD, the output is the same as "git describe HEAD".
           If the working tree has local modification "-dirty" is
           appended to it. If a repository is corrupt and Git cannot
           determine if there is local modification, Git will error out,
           unless ‘--broken’ is given, which appends the suffix
           "-broken" instead.

       --all
           Instead of using only the annotated tags, use any ref found
           in refs/ namespace. This option enables matching any known
           branch, remote-tracking branch, or lightweight tag.

       --tags
           Instead of using only the annotated tags, use any tag found
           in refs/tags namespace. This option enables matching a
           lightweight (non-annotated) tag.

       --contains
           Instead of finding the tag that predates the commit, find the
           tag that comes after the commit, and thus contains it.
           Automatically implies --tags.

       --abbrev=<n>
           Instead of using the default number of hexadecimal digits
           (which will vary according to the number of objects in the
           repository with a default of 7) of the abbreviated object
           name, use <n> digits, or as many digits as needed to form a
           unique object name. An <n> of 0 will suppress long format,
           only showing the closest tag.

       --candidates=<n>
           Instead of considering only the 10 most recent tags as
           candidates to describe the input commit-ish consider up to
           <n> candidates. Increasing <n> above 10 will take slightly
           longer but may produce a more accurate result. An <n> of 0
           will cause only exact matches to be output.

       --exact-match
           Only output exact matches (a tag directly references the
           supplied commit). This is a synonym for --candidates=0.

       --debug
           Verbosely display information about the searching strategy
           being employed to standard error. The tag name will still be
           printed to standard out.

       --long
           Always output the long format (the tag, the number of commits
           and the abbreviated commit name) even when it matches a tag.
           This is useful when you want to see parts of the commit
           object name in "describe" output, even when the commit in
           question happens to be a tagged version. Instead of just
           emitting the tag name, it will describe such a commit as
           v1.2-0-gdeadbee (0th commit since tag v1.2 that points at
           object deadbee....).

       --match <pattern>
           Only consider tags matching the given glob(7) pattern,
           excluding the "refs/tags/" prefix. If used with --all, it
           also considers local branches and remote-tracking references
           matching the pattern, excluding respectively "refs/heads/"
           and "refs/remotes/" prefix; references of other types are
           never considered. If given multiple times, a list of patterns
           will be accumulated, and tags matching any of the patterns
           will be considered. Use --no-match to clear and reset the
           list of patterns.

       --exclude <pattern>
           Do not consider tags matching the given glob(7) pattern,
           excluding the "refs/tags/" prefix. If used with --all, it
           also does not consider local branches and remote-tracking
           references matching the pattern, excluding respectively
           "refs/heads/" and "refs/remotes/" prefix; references of other
           types are never considered. If given multiple times, a list
           of patterns will be accumulated and tags matching any of the
           patterns will be excluded. When combined with --match a tag
           will be considered when it matches at least one --match
           pattern and does not match any of the --exclude patterns. Use
           --no-exclude to clear and reset the list of patterns.

       --always
           Show uniquely abbreviated commit object as fallback.

       --first-parent
           Follow only the first parent commit upon seeing a merge
           commit. This is useful when you wish to not match tags on
           branches merged in the history of the target commit.

EXAMPLES         top

       With something like git.git current tree, I get:

           [torvalds@g5 git]$ git describe parent
           v1.0.4-14-g2414721

       i.e. the current head of my "parent" branch is based on v1.0.4,
       but since it has a few commits on top of that, describe has added
       the number of additional commits ("14") and an abbreviated object
       name for the commit itself ("2414721") at the end.

       The number of additional commits is the number of commits which
       would be displayed by "git log v1.0.4..parent". The hash suffix
       is "-g" + an unambigous abbreviation for the tip commit of parent
       (which was 2414721b194453f058079d897d13c4e377f92dc6). The length
       of the abbreviation scales as the repository grows, using the
       approximate number of objects in the repository and a bit of math
       around the birthday paradox, and defaults to a minimum of 7. The
       "g" prefix stands for "git" and is used to allow describing the
       version of a software depending on the SCM the software is
       managed with. This is useful in an environment where people may
       use different SCMs.

       Doing a git describe on a tag-name will just show the tag name:

           [torvalds@g5 git]$ git describe v1.0.4
           v1.0.4

       With --all, the command can use branch heads as references, so
       the output shows the reference path as well:

           [torvalds@g5 git]$ git describe --all --abbrev=4 v1.0.5^2
           tags/v1.0.0-21-g975b

           [torvalds@g5 git]$ git describe --all --abbrev=4 HEAD^
           heads/lt/describe-7-g975b

       With --abbrev set to 0, the command can be used to find the
       closest tagname without any suffix:

           [torvalds@g5 git]$ git describe --abbrev=0 v1.0.5^2
           tags/v1.0.0

       Note that the suffix you get if you type these commands today may
       be longer than what Linus saw above when he ran these commands,
       as your Git repository may have new commits whose object names
       begin with 975b that did not exist back then, and "-g975b" suffix
       alone may not be sufficient to disambiguate these commits.

SEARCH STRATEGY         top

       For each commit-ish supplied, git describe will first look for a
       tag which tags exactly that commit. Annotated tags will always be
       preferred over lightweight tags, and tags with newer dates will
       always be preferred over tags with older dates. If an exact match
       is found, its name will be output and searching will stop.

       If an exact match was not found, git describe will walk back
       through the commit history to locate an ancestor commit which has
       been tagged. The ancestor’s tag will be output along with an
       abbreviation of the input commit-ish’s SHA-1. If --first-parent
       was specified then the walk will only consider the first parent
       of each commit.

       If multiple tags were found during the walk then the tag which
       has the fewest commits different from the input commit-ish will
       be selected and output. Here fewest commits different is defined
       as the number of commits which would be shown by git log
       tag..input will be the smallest number of commits possible.

BUGS         top

       Tree objects as well as tag objects not pointing at commits,
       cannot be described. When describing blobs, the lightweight tags
       pointing at blobs are ignored, but the blob is still described as
       <committ-ish>:<path> despite the lightweight tag being favorable.

GIT         top

       Part of the git(1) suite

COLOPHON         top

       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 2021-08-27.  (At that time,
       the date of the most recent commit that was found in the
       repository was 2021-08-24.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

Git 2.33.0.69.gc420321         08/27/2021                GIT-DESCRIBE(1)

Pages that refer to this page: git(1)git-diff-tree(1)git-log(1)git-rev-list(1)git-show(1)