Splitting a repository in two (by directory)

[Philip Pemberton]

Hi,
   I've been working on a project for a while (about 3 months), which 
consists of two parts: the application itself (the "core"), and a small 
web-admin interface. At the moment, both of these are stuffed into the 
same repository, but are fully capable of working independently.

At the moment, the repository looks like this:

   /hg/myapp
     /admin
       /adm_libs
       config.inc.php
       index.php
     /lib
       /smarty
         ... loads of files in here ...
       security.inc.php
       tests.inc.php
     /templates
       mainpage.tpl
     index.php
     install.php

What I want are two repositories, "myapp-admin" and "myapp-core", with 
/hg/myapp/admin/* in "myapp-admin", and the rest in "myapp-core". So far 
I've come up with a few ways of doing this:

   (1): Move admin into another directory, "hg init" that directory, "hg 
addrem", "hg commit", then push that to my server. Then remove admin 
from core, "hg commit". This of course means my version history for part 
of the admin side's development is in the "core" repo (mixed up with the 
changes for "core"), while the rest of it is in the "admin" repo.

   (2): Create two new repos called 'admin' and 'core'. Check out every 
single change from the source repo (/hg/myapp) one-by-one, copy the 
files into the two new repos as appropriate (admin files go into admin, 
everything else goes into core), and check the changes in. This would 
preserve the change history and comments as I'd like, and obviously if 
there are no changes that affect e.g. "core", then "hg commit" will just 
exit -- the comments will only apply to the part that actually changed.

Ideally I'd like to do something along the lines of (2). This way the 
changes that apply to 'core' stay with 'core', and the changes that 
apply to 'admin' stay with 'admin'. The problem is, I don't feel like 
typing "hg checkout -r{N}; cp -R {files} {elsewhere}; (cd elsewhere; hg 
commit)" and retyping (or at least copy-pasting) the changelog entries 
for nearly 100 changesets.

So finally, on to the million-dollar question: is there a better way to 
do this?

(a Google search for "mercurial split repository" seems to think not)

Thanks,
-- 
Phil.
lists at philpem.me.uk
http://www.philpem.me.uk/