Checking out multiple branches at the same time in git and moving files between them

Imagine that you're working on some branch that is out of sync with master and you have already made a lot of changes. All of the sudden you realise that you want to move some of the files to a new branch that will be sourced from master (i.e. changes are needed by other members of the team).

Git Worktrees

To do that, you first need to create a git worktree:

git worktree add <folder> master

This will basically create a folder with a repository and checkout master branch. It also creates a link between the new and the "original" repository folder.

You can use git worktree list to list worktrees and git worktree remove to remove them. For more information about git worktree please refer to the official documentation.

Moving files

As mentioned earlier, git worktree creates a link between local folders. That means that your stashes are the same between them. So you can just stash interactively necessary hunks with:

git stash -p

or you can git add unwanted changes, and git stash -k to stash the unstaged files.

Now you need to switch to the new worktree with master and create a new branch:

cd <folder>
git checkout -b new_branch

and do git stash apply. It's better to use apply most of the time and not pop since if you have some conflicts you can always abort without losing stashed changes.