This document explains how to move a subtree rooted at a given directory in one repository to a new path in another repository and ...
- maintain all the history,
- not require
--followfor the history to work, - not include any baggage, i.e. without superfluous commits that do not directly impinge upon the directory in question.
The following instructions assume that we want to move the contents of ./the/source/dir in some source repository to ./new/dir in some target repository.
Note: These two paths and the source repository URL<source-repo-url>are the only variables that you will need to adapt in the instructions below.
From the source branch in the source repository, create a new branch that contains only the data to be moved:
git subtree split -P the/source/dir -b temp-branch
This will cause data previously at ./the/source/dir/ in the source branch to be in ./ in the newly created branch temp-branch.
Since we want the data to end up in new/dir eventually, we rewrite the new branch’s history to move it there:
git checkout temp-branch
git filter-branch --prune-empty -f --tree-filter '
git ls-tree --name-only -r $GIT_COMMIT | egrep -v "^new/dir/" | xargs -L1 dirname | xargs -I thedir mkdir -pv new/dir/thedir
git ls-tree --name-only -r $GIT_COMMIT | egrep -v "^new/dir/" | xargs -I thepath mv -v thepath new/dir/thepath
'
Note that there are four occurrences of new/dir in the above snippet. The Python script moveToSubDir.py serves to assist in the adaptation of the command and prints an adapted version for you.
Add a remote for the source repository and merge the temporary branch we created.
git remote add –f source-repo <source-repo-url>
git merge source-repo/temp-branch --allow-unrelated-histories
Voila, you will have source-repo’s ./the/source/dir at ./new/dir in the target repository.