How to migrate a directory from git repository to another one preserving git history. Bitbucket example

Assume we migrate:

• The folder2 from git@bitbucket.org:myproject/myrepo.git

  myrepo
  │   README.md
  └───folder1
  └───folder2

• to git@bitbucket.org:newrepo.git

How to do this:

1. To make it safe, clone myrepo.git into a new directory
   

   mkdir myrepo-folder2-migration
   cd myrepo-folder2-migration
   
   git clone 
   git@bitbucket.org:myproject/myrepo.git
   
   cd myrepo
   
   #prevent pushing into it
   git remote rm origin
   

2. Filter git history to keep only files in folder2
   

   git filter-branch --subdirectory-filter folder2 -- --all
   

3. Clean unwanted data
   

   git reset --hard
   git gc --aggressive 
   git prune
   git clean -fd
   

4. It should contain only the files from folder2 in the root git directory now

5. Go back and prepare to work for the newrepo
   

   cd ..
   
   pwd
   #make sure you're in myrepo-folder2-migration
   

6. Clone the empty repository
   

   git clone git@bitbucket.org:newrepo.git
   
   cd newrepo
   

7. Create a connection to local repository, we're going to pull from it
   

   git remote add old-repo ../myrepo
   

8. Pull files from the old repo
   

   git pull old-repo master --allow-unrelated-histories
   

9. Remove the connection with local
   

   git remote remove old-repo
   

10. Push the changes to the remote origin
    

    git push
    

The new remote repository should contain files from folder2 inside the root directory now.

I followed https://medium.com/@ayushya/move-directory-from-one-repository-to-another-preserving-git-history-d210fa049d4b with adjustments I found important and clear for understanding.