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The git-splitter performs two operations: 

  - Split: Separates out all commits in a specific folder in a Git repository
  as a separate repository, removing the folder name, allowing the new 
  repository to be used as a submodule
  
  - Replant: Creates a new repository based on the commits in the source
  repository, prepending a folder name for all the files. This allows updates 
  in the submodule to be integrated in the original repository without 
  duplicating the commit history by rebasing new commits onto a branch in the 
  original repository
  
  The code also have the experimental functionality that tag each commit in 
  the repository with the original commit ID
 
Usage:

  splitter [split | replant] {options} {rev}
  
  rev is a commit or commit-range, by default master. Result of specifying 
  more than one rev is undefined 
  
Options:

  --prefix: Path to the folder that will be split off, or the path that will 
  be prepended on the filenames in the repository.
  
  --branch: Name of target branch
  
  --onto: Commit to put the converted commits on top of. Used if 
  
  --tag <name>: Experimental functionality: tag each split commit with 
  <name>-x-<from-commit>, and each replanted commit <name>-x--<commit> and 
  (if it exists) <name>-x-<from-commit>-<commit>. This allows mapping back 
  and forth between the original repository and the submodule.
  
  --repo <name>: Source git repo. Defaults to current directory. Use when 
  executing from a parent directory 
  
  --push <name>: Target git repo, path relative to work repo. The resulting 
  branch will be pushed to this repo.

Examples:

In "original" repo:

python ../git-splitter/splitter.py replant --branch my-master --prefix foldername --push ../my-module master

will take all files "foldername/path/example.ext" in the "foldername" directory
and remove the "foldername" prefix, and copy the files and their commit history
into the my-module repository as the branch "my-master"


In "my-module" repo

python ../git-splitter/splitter.py replant --branch mymodule-master --prefix foldername --push ../module-migrate my-master

will convert all all files path/example.ext to foldername/path/example.ext, 
with the same history, and will push it to the module-migrate repository as
the branch mymodule-master, which can then be fetched into the "original" code 
repository, and new commits can then be rebased (or merged) into the original
code base.