[RFC] git-cvs script

[Nick Woolley <nickwoolley@yahoo.co.uk>]

Hi,

I have script which wraps git-cvsimport and git-cvsexport, called "git-cvs".

The main aim of the script is to automate the steps for tracking a CVS
repository with the git-cvs* commands.

It's not currently as sophisticated as git-svn, it's undoubtably flawed and
isn't foolproof (e.g. exports to CVS of merged git histories can be
problematic), but I find it useful, because a lot of the nitty-gritty is done
for me.

I'd like to ask:

 - Is this at all useful to anyone else in it's current form?

 - Is there any prior art I should be aware of? (Presumably most people
   just roll their own scripts, like I have)

 - Bearing in mind that it's a work-in progress, are there any suggestions for
   improvement?


The script can be found in its current state here:

 http://github.com/wu-lee/git-cvs/


There's no installer, but the script is self-contained and just needs to be on
the execution $PATH (as well as git and cvs).

Given a CVS repository at $CVS_ROOT, tracking a module $CVS_MODULE can be done
like this:

 # Create a git repo
 git init

 # Initialise git-cvs's config file
 echo cvsroot=$CVS_ROOT      >.git-cvs
 echo cvsmodule=$CVS_MODULE >>.git-cvs

 # First pull gets cvs files using git-cvsimport
 # (optionally you can supply the option
 # --author-file <authormap> for pass-through
 # to git-cvsimport -A on subsequent invocations)
 git-cvs pull

 # hack hack...

 # Push the files back into CVS with git-cvsexportcommit
 # (This pushes the commits master..remotes/cvs/cvshead by default,
 # or cvsworking/NAME..remotes/cvs/NAME for each CVS branch NAME)
 git-cvs push

 # Pull the changes back into remote/cvs/cvshead and
 # (a messy part I've not found a way round yet) throw away our
 # locally merged commits
 git-cvs pull
 git reset --hard master

 # More hacking...

 # Repeat push/pull steps as needed


Some other points:

 - Changes in CVS get pulled back, including multiple branches.

 - An author-mapping file can be supplied as for cvs-import -A

 - The script creates local CVS working directories
   .git/git-cvs/cvscheckout/NAME, one for each CVS branch NAME.

 - Git's master branch tracks CVS's HEAD branch.

 - A git branch cvsworking/NAME is created to track each CVS branch NAME.

 - Edits in these branches get pushed back to the appropriate CVS branches.

 - Verbose subcommand output currently goes into .git/git-cvs/logs.

 - Invoking git-cvs with no parameters gets information about the options.

 - In an emergency, a list of commit ids can be supplied to git-cvs push.

 - Written in Perl, uses only core modules (tested with v5.8.8)

 - There is a small test suite in t/, run individually or with "prove/*.t"



Thanks,

Nick