How to prepare and apply multiple patches for the last N commits in git

Question

I need to create a patch file for the last N commits and apply them as separate commits to another branch. For N=3 I assume I have to do this:

git diff HEAD~3 HEAD~2 >> diff1
git diff HEAD~2 HEAD~1 >> diff2
git diff HEAD~1 HEAD >> diff3

and then apply them on another branch respectively:

git apply diff1
(push)
git apply diff2
(push)
git apply diff3

Is there any shorter way to do this?

score 17 · Accepted Answer · answered May 06 '17 at 00:52

17

This can be done with git format-patch and git am, respectively. From your example, try:

git format-patch HEAD~3

This will generate files 0001-commit-foo.patch, 0002-commit-bar.patch, 0003-commit-baz.patch. Then you can copy them to another repo and use git am to apply them:

git am *.patch

This will preserve the commits as you made them in the previous tree including commit messages, SHAs, and timestamps.

answered May 06 '17 at 00:52

nasamuffin

458
3
10

If anyone struggle with "fatal: could not open '*.patch' for reading: Invalid argument" error message from msysgit, here is why: https://groups.google.com/forum/#!topic/msysgit/1IT785Jf4Zo – Ilya Jun 23 '17 at 20:52

score 1 · Answer 2 · edited May 23 '17 at 12:26

1

Try git cherry-pick commits to another branch (no need to create temporary patches). This questions answers how to cherry-pick multiple commits at a time: How to cherry-pick multiple commits

edited May 23 '17 at 12:26

Community

1
1

answered Oct 30 '16 at 11:35

TomaszGuzialek

861
1
8
15

I need the patch. The branches are on two different projects. – B Faley Oct 30 '16 at 11:45
1

You can still cherry-pick between different repositories if you add the second repo as a remote to the first one. – TomaszGuzialek Oct 30 '16 at 11:53

score 1 · Answer 3 · answered Oct 30 '16 at 11:53

You've mentioned in a comment that you need the patches, because the branches are on different projects. That's not a problem. You can add a remote for the other project, and you can cherry-pick from it, even if they don't share a common history. Cherry-picking doesn't concern ancestry, it's just about replaying changes, just as you would with patches.

If for some reason cherry picking is really not an option for you (though I really doubt), you can use loops in Bash, for example:

for ((i = 3, d = 1; i > 0; i--, d++)); do ((j = i - 1)); git diff HEAD~$i HEAD~$j > diff$d; done

You can write a similar loop for the git apply commands.

How to prepare and apply multiple patches for the last N commits in git

3 Answers3