How to cherry-pick a range of commits and merge them into another branch?

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I have the following repository layout:

  • master branch (production)
  • integration
  • working

What I want to achieve is to cherry-pick a range of commits from the working branch and merge it into the integration branch. I'm pretty new to git and I can't figure out how to exactly do this (the cherry-picking of commit ranges in one operation, not the merging) without messing the repository up. Any pointers or thoughts on this? Thanks!

10 Answers

When it comes to a range of commits, cherry-picking is was not practical.

As mentioned below by Keith Kim, Git 1.7.2+ introduced the ability to cherry-pick a range of commits (but you still need to be aware of the consequence of cherry-picking for future merge)

git cherry-pick" learned to pick a range of commits
(e.g. "cherry-pick A..B" and "cherry-pick --stdin"), so did "git revert"; these do not support the nicer sequencing control "rebase [-i]" has, though.

damian comments and warns us:

In the "cherry-pick A..B" form, A should be older than B.
If they're the wrong order the command will silently fail.

If you want to pick the range B through D (including B) that would be B^..D (instead of B..D).
See "Git create branch from range of previous commits?" as an illustration.

As Jubobs mentions in the comments:

This assumes that B is not a root commit; you'll get an "unknown revision" error otherwise.

Note: as of Git 2.9.x/2.10 (Q3 2016), you can cherry-pick a range of commit directly on an orphan branch (empty head): see "How to make existing branch an orphan in git".


Original answer (January 2010)

A rebase --onto would be better, where you replay the given range of commit on top of your integration branch, as Charles Bailey described here.
(also, look for "Here is how you would transplant a topic branch based on one branch to another" in the git rebase man page, to see a practical example of git rebase --onto)

If your current branch is integration:

# Checkout a new temporary branch at the current location
git checkout -b tmp

# Move the integration branch to the head of the new patchset
git branch -f integration last_SHA-1_of_working_branch_range

# Rebase the patchset onto tmp, the old location of integration
git rebase --onto tmp first_SHA-1_of_working_branch_range~1 integration

That will replay everything between:

  • after the parent of first_SHA-1_of_working_branch_range (hence the ~1): the first commit you want to replay
  • up to "integration" (which points to the last commit you want to replay, from the working branch)

to "tmp" (which points to where integration was pointing before)

If there is any conflict when one of those commits is replayed:

  • either solve it and run "git rebase --continue".
  • or skip this patch, and instead run "git rebase --skip"
  • or cancel the all thing with a "git rebase --abort" (and put back the integration branch on the tmp branch)

After that rebase --onto, integration will be back at the last commit of the integration branch (that is "tmp" branch + all the replayed commits)

With cherry-picking or rebase --onto, do not forget it has consequences on subsequent merges, as described here.


A pure "cherry-pick" solution is discussed here, and would involve something like:

If you want to use a patch approach then "git format-patch|git am" and "git cherry" are your options.
Currently, git cherry-pick accepts only a single commit, but if you want to pick the range B through D that would be B^..D in git lingo, so

git rev-list --reverse --topo-order B^..D | while read rev 
do 
  git cherry-pick $rev || break 
done 

But anyway, when you need to "replay" a range of commits, the word "replay" should push you to use the "rebase" feature of Git.

Are you sure you don't want to actually merge the branches? If the working branch has some recent commits you don't want, you can just create a new branch with a HEAD at the point you want.

Now, if you really do want to cherry-pick a range of commits, for whatever reason, an elegant way to do this is to just pull of a patchset and apply it to your new integration branch:

git format-patch A..B
git checkout integration
git am *.patch

This is essentially what git-rebase is doing anyway, but without the need to play games. You can add --3way to git-am if you need to merge. Make sure there are no other *.patch files already in the directory where you do this, if you follow the instructions verbatim...

git cherry-pick start_commit_sha_id^..end_commit_sha_id

e.g. git cherry-pick 3a7322ac^..7d7c123c

Assuming you are on branchA where you want to pick commits (start & end commit SHA for the range is given and left commit SHA is older) from branchB. The entire range of commits (both inclusive) will be cherry picked in branchA.

The examples given in the official documentation are quite useful.

I have tested that some days ago, after reading the very clear explanation of Vonc.

My steps

Start

  • Branch dev : A B C D E F G H I J
  • Branch target: A B C D
  • I don't want E nor H

Steps to copy features without the step E and H in the branch dev_feature_wo_E_H

  • git checkout dev
  • git checkout -b dev_feature_wo_E_H
  • git rebase --interactive --rebase-merges --no-ff D where I put drop front of E and H in the rebase editor
  • resolve conflicts, continue and commit

Steps to copy the branch dev_feature_wo_E_H on target.

  • git checkout target
  • git merge --no-ff --no-commit dev_feature_wo_E_H
  • resolve conflicts, continue and commit

Some remarks

  • I've done that because of too much cherry-pick in the days before

  • git cherry-pick is powerful and simple but

    • it creates duplicates commits
    • and when I want to merge I have to resolve conflicts of the initial commits and duplicates commits, so for one or two cherry-pick, it's OK to "cherry-picking" but for more it's too verbose and the branch will become too complex
  • In my mind the steps I've done are more clear than git rebase --onto

git cherry-pick FIRST^..LAST works only for simple scenarios.

To achieve a decent "merge it into the integration branch" while having the usal comfort with things like auto-skipping of already integrated picks, transplanting diamond-merges, interactive control ...) better use a rebase. One answer here pointed to that, however the protocol included a dicey git branch -f and a juggling with a temp branch. Here a straight robust method:

git rebase -i FIRST LAST~0 --onto integration
git rebase @ integration

The -i allows for interactive control. The ~0 ensures a detached rebase (not moving the / another branch) in case LAST is a branch name. It can be omitted otherwise. The second rebase command just moves the integration branch ref in safe manner forward to the intermediate detached head - it doesn't introduce new commits. To rebase a complex structure with merge diamonds etc. consider --rebase-merges or --rebase-merges=rebase-cousins in the first rebase.

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