GIT: Move folder between repositories with `git filter-branch`

script.sh

# Clone the source repository

git clone git@github.com:titenkov/api.git

# Clean up the git to have only the data and history related to the folder you need

git filter-branch -f --subdirectory-filter client/src/integrationtest -- -- all

# Move content to some folder matching the desired path in target repository (simpler to merge later)

mkdir -p ext/src/integrationtest
git mv java ext/src/integrationtest
git mv groovy ext/src/integrationtest

# Commit your changes, but don't push!

git commit -m 'integration tests'


# Move to the destination repository
# Add a remote repo using the local reference

git remote add api ../api/

# Fetch the remote and merge the branch
git fetch api
git branch api remotes/api/master
git merge api --allow-unrelated-histories

# Clean up

git remote rm api
git branch -D api

# DONE!