What does cherry-picking a commit with git mean?

问题:

Recently, I have been asked to cherry pick a commit. But I have no idea what it means. So what does cherry picking a commit in git mean? How do you do it?

回答1:

Cherry picking in Git means to choose a commit from one branch and apply it onto another.

This is in contrast with other ways such as merge and rebase which normally apply many commits onto another branch.

1. Make sure you are on the branch you want to apply the commit to.

   git checkout master
   

2. Execute the following:

   git cherry-pick <commit-hash>
   

N.B.:

1. If you cherry-pick from a public branch, you should consider using

   git cherry-pick -x <commit-hash>
   

   This will generate a standardized commit message. This way, you (and your co-workers) can still keep track of the origin of the commit and may avoid merge conflicts in the future.

2. If you have notes attached to the commit they do not follow the cherry-pick. To bring them over as well, You have to use:

   git notes copy <from> <to>
   

Additional links:

• git official guide page

回答2:

This quote is taken from; Version Control with Git (Really great book, I encourage you to buy it if you are interested in git)

Edit: Since this answer is still getting impression, I would like to add very nice in action video tutorial about it:

Youtube: Introduction to Git cherry-pick

Using git cherry-pick The command git cherry-pick commit applies the changes introduced by the named commit on the current branch. It will introduce a new, distinct commit. Strictly speaking, using git cherry-pick doesn’t alter the existing history within a repository; instead, it adds to the history. As with other Git operations that introduce changes via the process of applying a diff, you may need to resolve conflicts to fully apply the changes from the given commit . The command git cherry-pick is typically used to introduce particular commits from one branch within a repository onto a different branch. A common use is to forward- or back-port commits from a maintenance branch to a development branch.

$ git checkout rel_2.3
$ git cherry-pick dev~2 # commit F, above

before:

after:

回答3:

Cherry picking in Git is designed to apply some commit from one branch into another branch. It can be done if you eg. made a mistake and committed a change into wrong branch, but do not want to merge the whole branch. You can just eg. revert the commit and cherry-pick it on another branch.

To use it, you just need git cherry-pick hash, where hash is a commit hash from other branch.

For full procedure see: http://technosophos.com/2009/12/04/git-cherry-picking-move-small-code-patches-across-branches.html

回答4:

cherry-pick is a Git feature. If someone wants to Commit specific commits in one branch to a target branch, then cherry-pick is used.
git cherry-pick steps are as below.

1. checkout (switch to) target branch.

2. git cherry-pick <commit id>
   

   Here commit id is activity id of another branch.Eg.

   git cherry-pick 9772dd546a3609b06f84b680340fb84c5463264f
   

3. push to target branch

Visit https://git-scm.com/docs/git-cherry-pick

回答5:

You can think if a cherry pick as similar to a rebase, or rather it\'s managed like a rebase. By this, I mean that it takes an existing commit and regenerates it taking, as the starting point, the head of the branch you\'re currently on.

A rebase takes a commit that had a parent X and regenerates the commit as if it actually had a parent Y, and this is precisely what a cherry-pick does.

Cherry pick is more about how you select the commits. With pull (rebase), git implicitly regenerates your local commits on top of what\'s pulled to your branch, but with cherry-pick you explicitly choose some commit(s), and implicitly regenerate it (them) on top of your current branch.

So the way you do it differs, but under the hood they are very similar operations - the regeneration of commits.

回答6:

It\'s kind of like Copy (from somewhere) and Paste (to somewhere), but for specific commits.

If you want to do a hot fix, for example, then you can use the cherry-pick feature.

Do your cherry-pick in a development branch, and merge that commit to a release branch. Likewise, do a cherry-pick from a release branch to master. Voila

回答7:

Short example of situation, when you need cherry pick

Consider following scenario. You have two branches.

a) release1 - This branch is going to your customer, but there are still some bugst to be fixed.

B) master - Classic master branch, where you can for example add functionality for release2.

NOW: You fix something in release1. Of course you need this fix also in master. And that is typical use-case for cherry picking. So cherry pick in this scenario means that you take commit from release1 and merges it also into master.