GIT-DESCRIBE(1)GIT-DESCRIBE(1)NAMEgit-describe - Show the most recent tag that is reachable from a commit
SYNOPSIS
git describe [--all] [--tags] [--contains] [--abbrev=<n>] <committish>...
git describe [--all] [--tags] [--contains] [--abbrev=<n>] --dirty[=<mark>]
DESCRIPTION
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.
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).
OPTIONS
<committish>...
Committish object names to describe.
--dirty[=<mark>]
Describe the working tree. It means describe HEAD and appends
<mark> (-dirty by default) if the working tree is dirty.
--all Instead of using only the annotated tags, use any ref found in
.git/refs/. This option enables matching any known branch,
remote branch, or lightweight tag.
--tags Instead of using only the annotated tags, use any tag found in
.git/refs/tags. 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. Automati-
cally implies --tags.
--abbrev=<n>
Instead of using the default 7 hexadecimal digits as the abbre-
viated 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.
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GIT-DESCRIBE(1)GIT-DESCRIBE(1)
--candidates=<n>
Instead of considering only the 10 most recent tags as candi-
dates to describe the input committish consider up to <n> candi-
dates. 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 sup-
plied 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 hap-
pens 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 pattern (can be used to
avoid leaking private tags made from the repository).
--always
Show uniquely abbreviated commit object as fallback.
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 few commits on top of that, describe has added the num-
ber 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). The "g" prefix stands for
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GIT-DESCRIBE(1)GIT-DESCRIBE(1)
"git" and is used to allow describing the version of a software depend-
ing on the SCM the software is managed with. This is useful in an envi-
ronment 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 out-
put 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 suf-
ficient to disambiguate these commits.
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 pre-
ferred 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 com-
mits which would be shown by git log tag..input will be the smallest
number of commits possible.
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GIT-DESCRIBE(1)GIT-DESCRIBE(1)AUTHOR
Written by Linus Torvalds <torvalds@osdl.org: mailto:tor-
valds@osdl.org>, but somewhat butchered by Junio C Hamano <git-
ster@pobox.com: mailto:gitster@pobox.com>. Later significantly updated
by Shawn Pearce <spearce@spearce.org: mailto:spearce@spearce.org>.
DOCUMENTATION
Documentation by David Greaves, Junio C Hamano and the git-list
<git@vger.kernel.org: mailto:git@vger.kernel.org>.
GIT
Part of the git(1) suite
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