I have two branches in Git, A and B. I want to be in branch B and ”checkout” the complete ”state” (not history) of A but still be in B, and then commit that as one single change of B.

So files that are present in B but not A are deleted in that commit, files are present in A but not B are created in the commit, and files that differ between A and B are modified in B. So the history of B is kept but the ”states” of A and B are identical.

How do I do that?

CodePudding user response：

The old way of doing that would be (assuming you are on B already):

git checkout A -- .
git commit -m "single change to get to A's content"

The new way is:

git restore --worktree --staged --source=A -- .
git commit -m "single commit to get to A's content"

The longer but possible way would be:

git checkout --detach A
git reset --soft B # set the branch pointer (well, HEAD, actually) to where B points to
git commit -m "single commit to get to A's content"
# now you have this single revision after B that has the same content of A
# set B over here and checkout
git branch -f B
git checkout B

That would also work.