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GIT\-DESCRIBE

Section: Git Manual (1)
Updated: 09/30/2007
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NAME

git-describe - Show the most recent tag that is reachable from a commit  

SYNOPSIS

git-describe [--all] [--tags] [--contains] [--abbrev=<n>] <committish>...  

DESCRIPTION

The command finds the most recent tag that is reachable from a commit, and if the commit itself is pointed at by the tag, shows the tag. Otherwise, it suffixes the tag name with the number of additional commits and the abbreviated object name of the commit.  

OPTIONS

<committish>

The object name of the committish.

--all

Instead of using only the annotated tags, use any ref found in .git/refs/.

--tags

Instead of using only the annotated tags, use any tag found in .git/refs/tags.

--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 8 hexadecimal digits as the abbreviated object name, use <n> digits.

--candidates=<n>

Instead of considering only the 10 most recent tags as candidates to describe the input committish consider up to <n> candidates. Increasing <n> above 10 will take slightly longer but may produce a more accurate result.

--debug

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

EXAMPLES

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 handful 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" + 7-char abbreviation for the tip commit of parent (which was 2414721b194453f058079d897d13c4e377f92dc6).

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 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
 

SEARCH STRATEGY

For each committish 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 committish's SHA1.

If multiple tags were found during the walk then the tag which has the fewest commits different from the input committish 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.  

AUTHOR

Written by Linus Torvalds <torvalds@osdl.org>, but somewhat butchered by Junio C Hamano <junkio@cox.net>. Later significantly updated by Shawn Pearce <spearce@spearce.org>.  

DOCUMENTATION

Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.  

GIT

Part of the git(7) suite


 

Index

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
EXAMPLES
SEARCH STRATEGY
AUTHOR
DOCUMENTATION
GIT




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