Jenkins: How to checkout only new files and modified files when creating new branch

Question

I am using Multibranch pipeline in Jenkins. I've some pretty large project - When creating a new branch, I'd like the git plugin to only checkout new files or changed files compared to a branch

Is there a way to do that? I know once the branch exist, as long as I don't clean the workspace, it will just checkout new files and updated one, but what about new branches?

Answer 1

Say you have two branches, 'old-branch' and 'new-branch', both of which are synced with the remote.

git checkout old-branch
# Create a local branch called "new-branch"
# WARNING! Could blow away commits if you added them to to an existing local branch called "new-branch"
git switch -C new-branch 
# Set the branch's HEAD without doing a checkout
git reset --soft origin/new-branch
# Un-stage staged changes
git reset

The repo's working copy of its files will be what they were before we started. Run git status to see differences.

• If a new file was added to new-branch it'll show up as deleted .
• If a file was removed in new-branch , it'll show up as untracked.
• If a file was modified, it'll show up as modified.

If you then run:

git checkout .

This will undo all the modifications, and restore all the "deleted" (according to git) files, but importantly will not remove the untracked files . This accomplishes what your original question states.