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VCI::VCS::Hg - Object-oriented interface to Mercurial (aka Hg)


 use VCI;
 my $repository = VCI->connect(type => 'Hg',
                               repo => '');


This is a "driver" for VCI for the Mercurial version-control system. You can find out more about Mercurial at

For information on how to use VCI::VCS::Hg, see VCI.

Currently VCI::VCS::Hg actually interacts with HgWeb, not directly with Hg repositories. The only supported connections are http:// or https://.

Local repositories are not yet supported.


For the repo argument to "connect" in VCI, choose the actual root of your hgweb installation.

For example, for, the repo would be


Mercurial has two revision identifiers on a commit: an integer and a hex string. VCI::VCS::Hg uses the hex string as the revision id for Commit, File, and Directory objects, and does not understand integer revision ids.


These are limitations of VCI::VCS::Hg compared to the general API specified in the VCI::Abstract modules.


You can only connect to hgweb installations. You cannot use ssh, static-http, or local repositories. In the future we plan to support local repositories, but ssh and static-http repositories will probably never be supported. (Mercurial cannot work with them without cloning them, at which point they are just a local repository.)


  • Directory objects without a revision specified (such as those that you get through get_path, get_directory, and "get_file" in VCI::Abstract::Project) will always have the revision "tip", even if this wasn't the revision they were modified most recently in.

    This also means that their time will be the time of the tip revision, not the time they were last modified.

  • File objects in a Directory's contents will always have their latest revision ID, instead of the correct revision ID for that revision of the Directory.

    Directory objects in contents will have the revision identifier of the parent directory.


When directories were added/removed is not tracked by Mercurial, so Directory objects never show up in a History.


  • Although Mercurial supports renames and copies of files, the hgweb interface doesn't track renames and copies. So renames just look like a file was deleted and then a file was added. Copies are simply added files.

  • Mercurial doesn't track when directories were added or removed, so Directory objects never show up in the contents of a Commit.

  • If a File is added but has no content (that is, it's an empty file), it will not show up as "added" in the Commit where it was added. (It will show up in some later commit as "modified" if somebody adds contents, though.)

    Similarly, empty files that are removed will not show up in "removed".


On remote repositories, many operations can be extremely slow. This is because VCI::VCS::Hg makes many calls to the web interface, and any delay between you an the remote server is magnified by the fact that it happens over and over.

Working with the History of a Project involves using the RSS version of the changelog from hgweb. The more items you allow hgweb to display in the RSS version of the changelog, the faster VCI::VCS::Hg will be when working with the history of a Project.

Getting the contents (or added/removed/modified) of a Commit can be slow, as it has to access the web interface.




Max Kanat-Alexander <>


Copyright 2007-2010 by Everything Solved, Inc.

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