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NAME

Git::DescribeVersion - Use git-describe to show a repo's version

VERSION

version 1.015

SYNOPSIS

  use Git::DescribeVersion ();
  print Git::DescribeVersion->new({opt => 'value'})->version();

DESCRIPTION

Use git describe to determine a git repo's version.

This is the main module, though it's probably more useful run from the shell:

  $ git describe-version

The included git-describe-version script wraps Git::DescribeVersion::App.

NOTE: This module requires git version 1.5.5 or greater.

The version is determined by counting the commits since the most recent tag (matching the "match_pattern") and using that count as the final part of the version.

So to create a typical three part version (v1.2.3) repo tags should be made of the first two parts (v1.2) and the number of commits counted by git-describe will become the third part (v1.2.35).

METHODS

new

The constructor accepts a hash or hashref of options:

  Git::DescribeVersion->new({opt => 'value'});
  Git::DescribeVersion->new(opt1 => 'v1', opt2 => 'v2');

See "OPTIONS" for an explanation of the available options.

format_version

Format the supplied version object according to the "format" attribute.

git

A method to wrap the git commands. Attempts to use Git::Repository or Git::Wrapper. Falls back to using backticks.

parse_version

A method to take the version parts found and return the end result.

Uses the version module to parse.

version

The version method is the main method of the class. It attempts to return the repository version.

It will first use "version_from_describe".

If that fails it will try to simulate the functionality with "version_from_count_objects" and will start the count from the "first_version" option.

version_from_describe

Use git-describe to count the number of commits since the last tag matching "match_pattern".

It effectively calls

  git describe --match "${match_pattern}" --tags --long

If no matching tags are found (or some other error occurs) it will return undef.

version_from_count_objects

Use git-count-objects to count the number of commit objects in the repository. It then appends this count to "first_version".

It effectively calls

  git count-objects -v

and sums up the counts for 'count' and 'in-pack'.

OPTIONS

These options can be passed to "new":

directory

Directory in which git should operate. Defaults to ".".

first_version

If the repository has no tags at all, this version is used as the first version for the distribution.

Then git objects will be counted and appended to create a version like v0.1.5.

If set to undef then "version" will return undef if "version_from_describe" cannot determine a value.

Defaults to v0.1.

format

Specify the output format for the version number.

I had trouble determining the most reasonable names for the formats so a few variations are possible. (Pick the one which makes the most sense to you.)

  • dotted, normal, v-string or v

    for values like v1.2.3.

  • no-v-string (or no-v or no_v)

    to discard the opening v for values like 1.2.3.

  • decimal

    for values like 1.002003.

Defaults to decimal for compatibility.

version_regexp

Regular expression that matches a tag containing a version. It must capture the version into $1.

Defaults to ([0-9._]+) which will simply capture the first dotted-decimal found. This matches tags like v0.1, rev-1.2 and even release-2.0-skippy.

match_pattern

A shell-glob-style pattern to match tags. This is passed to git-describe to help it find the right tag from which to count commits.

Defaults to v[0-9]*.

HISTORY / RATIONALE

This module started out as a line in a Makefile:

  VERSION = $(shell (cd $(srcdir); \
    git describe --match 'v[0-9].[0-9]' --tags --long | \
    grep -Eo 'v[0-9]+\.[0-9]+-[0-9]+' | tr - . | cut -c 2-))

As soon as I wanted it in another Makefile (in another repository) I knew I had a problem.

Then when I started learning Dist::Zilla I found Dist::Zilla::Plugin::Git::NextVersion but missed the functionality I was used to with git-describe.

I started by forking Dist::Zilla::Plugin::Git on github, but realized that if I wrote the logic into a Dist::Zilla plugin it wouldn't be available to my git repositories that weren't Perl distributions.

So I wanted to extract the functionality to a module, make a separate Dist::Zilla::Role::VersionProvider plugin, and include a quick version that could be run with a minimal command line statement (so that I could put that in my Makefiles).

TODO

  • Allow using git-log to count commits affecting a subdirectory

  • Allow for more complex regexps (multiple groups) if there is a need.

  • Options for raising errors versus swallowing them?

  • Consider a dynamic installation to test `git --version`.

SEE ALSO

SUPPORT

Perldoc

You can find documentation for this module with the perldoc command.

  perldoc Git::DescribeVersion

Websites

The following websites have more information about this module, and may be of help to you. As always, in addition to those websites please use your favorite search engine to discover more resources.

Bugs / Feature Requests

Please report any bugs or feature requests by email to bug-git-describeversion at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Git-DescribeVersion. You will be automatically notified of any progress on the request by the system.

Source Code

https://github.com/rwstauner/Git-DescribeVersion

  git clone https://github.com/rwstauner/Git-DescribeVersion.git

AUTHOR

Randy Stauner <rwstauner@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2010 by Randy Stauner.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.