the Hg-Git mercurial plugin

This is the Hg-Git plugin for Mercurial, adding the ability to push to and pull from a Git server repository from Mercurial. This means you can collaborate on Git based projects from Mercurial, or use a Git server as a collaboration point for a team with developers using both Git and Mercurial.

The Big Idea

The Hg-Git plugin can convert commits/changesets losslessly from one system to another, so you can push via a Mercurial repository and another Mercurial client can pull it. In theory, the changeset IDs should not change, although this may not hold true for complex histories.

Commands

You can clone a Git repository from Mercurial by running hg clone [url]. It will create a directory with the same name as the last path component. For example, if you were to run hg clone git://github.com/schacon/munger.git it would clone the repository down into the directory 'munger.git', then convert it to a Mercurial repository for you.

hg clone git://github.com/schacon/munger.git

If you are starting from an existing Mercurial repository, you have to setup a Git repository somewhere that you have push access to, and then run hg push [path] from within your project. For example:

$ cd hg-git # (a Mercurial repository)
$ hg bookmark -r default master # make a bookmark of master for default, so a ref gets created
$ hg push git+ssh://git@github.com/schacon/hg-git.git
$ hg push

This will convert all our Mercurial data into Git objects and push them up to the Git server. You can also put that path in the [paths] section of .hg/hgrc and then push to it by name.

Now that you have a Mercurial repository that can push/pull to/from a Git repository, you can get updates with hg pull.

$ hg pull

That will pull down any commits that have been pushed to the server in the meantime and give you a new head that you can merge in.

Installing

Installing Hg-Git the easy way:

First, make sure that you have a working C compiler on your system. On Windows, one option is the free Microsoft Visual C++. (Be sure to install the 2008 version for compatibility reasons.) On Debian-style Linux, run apt-get install python-dev.

Secondly, run easy_install hg-git. If you don't have easy_install available, you can get it as part of Python's setuptools package.

Lastly, make sure the following is in your ~/.hgrc:

[extensions]
hgext.bookmarks =
hggit = 

...and that's it!

Installing Hg-Git manually

Use this method if you'd like to install a clone of the Hg-Git repository rather than a static package, or if you'd like to install Hg-Git in a location you choose yourself.

First, install version 0.8.0 or newer of Dulwich. You can do easy_install 'dulwich>=0.8.0' if you have setuptools installed. Next, clone the Hg-Git repository somewhere. Lastly, make the 'extensions' section in your '~/.hgrc' file look something like this:

[extensions]
hgext.bookmarks =
hggit = [path-to]/hg-git/hggit

That will enable the Hg-Git extension for you. The bookmarks section is only required prior to hg 1.7. Bookmarks will be translated to git heads when pushing.

Dependencies

Different versions of hg-git are known to work with different versions of Mercurial. For the most accurate info, go to the source on bitbucket, click the dropdown menu that says "default", click the "Tags" tab, select the version you've installed, and click on the file "Makefile". There's a line that starts with "all-version-tests" which lists the versions of Mercurial known to work.

It also needs Dulwich version 0.8.0 or later; Dulwich is a pure-Python implementation of the Git file formats and protocols. There are no Git binary dependencies: you do not need to have Git installed on your system.

Sources

Source available via hg (canonical repo) or git (mirror of hg). Patches preferred via email to the hg-git mailing list.

This plugin was originally developed by the folks at GitHub, and is currently maintained by Augie Fackler.