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How to split a git branch into two branches?

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git

branch

split

People also ask

Can you be in two git branches at once?

You can have many branches in your repository, but only one of these will be "checked out" as the working-tree so that you can work on it and make changes. git worktree adds the concept of additional working trees. This means you can have two (or more) branches checked-out at once.


For a more general answer that will help us understand things a bit better than just "run this command", we need a larger example. So, let's pretend you're actually in this situation:

---A---B---C <= Master
            \
             E---F---F---H <= Foo
                          \
                           J---K---L---M <= Bar
                                        \
                                         N---O---P---Q <= Baz

And here is what we'd like to have…

---A---B---C <= Master
           |\
           | E---F---F---H <= Foo
           |\
           | J---K---L---M <= Bar
            \
             N---O---P---Q <= Baz

Thankfully, Git has a solution for us in the options to the rebase command!

git rebase --onto [newParent] [oldParent] [branchToMove]

What this means can be broken down into parts:

  1. rebase - Change the parents of something
  2. --onto - This is the flag that tells git to use this alternate rebase syntax
  3. newParent - This is the branch that the branch you are rebasing will have as it's parent
  4. oldParent - This is the branch that the branch you are rebasing currently has as it's parent
  5. branchToMove - This is the branch that you are moving (rebasing)

The bit about "old parent branch" can be a little confusing, but what it's really doing is it's saying "ignore the changes from my old parent when doing the rebase". The oldParent is how you define where the branch you are moving (ie. branchToMove) starts.

So, what are the commands to execute in our situation?

git rebase --onto Master Bar Baz
git rebase --onto Master Foo Bar

Note that the order of these commands matter because we need to pull each branch off of the end of the "branch chain".


It looks to me like you could:

git checkout J
git rebase master

Edit:

I tried what I suggested and it doesn't work. knittl's suggestion doesn't work (on my box). Here's what did work for me:

git rebase --onto master foo bar

You can rebase your Bar branch onto master:

git rebase --onto C H M

If some patches conflict, you have to resolve them manually (but you also have to do that when cherry picking). Word of caution: don't rebase when the history has been published already.