Git: How to create patches for a merge?

by

There does not seem to be a solution producing individual commits à la git format-patch, but FWIW, you can format a patch containing the effective merge commit, suitable/compatible with git am:

Apparently, the Git Reference guide provides the first hint:

git log -p show patch introduced at each commit

[…] That means for any commit you can get the patch that commit introduced to the project. You can either do this by running git show [SHA] with a specific commit SHA, or you can run git log -p, which tells Git to put the patch after each commit. […]

Now, the manual page of git-log gives the second hint:

git log -p -m --first-parent

… Shows the history including change diffs, but only from the “main branch” perspective, skipping commits that come from merged branches, and showing full diffs of changes introduced by the merges. This makes sense only when following a strict policy of merging all topic branches when staying on a single integration branch.

Which in turn means in concrete steps:

# Perform the merge:
git checkout master
git merge feature
... resolve conflicts or whatever ...
git commit

# Format a patch:
git log -p --reverse --binary --pretty=email --stat -m --first-parent origin/master..HEAD > feature.patch

And this can be applied as intended:

git am feature.patch

Again, this won’t contain the individual commits, but it produces a git am compatible patch out of a merge commit.

Of course, if you don’t need a git am compatible patch in the first place, then it’s way simpler:

git diff origin/master > feature.patch

But I guess you already figured as much, and if you landed on this page here, you are actually searching for the workaround/solution I’ve described above. 😉

More Related Contents:

  1. Evil merges in git?
  2. What is the difference between merge –squash and rebase?
  3. What effect does the `–no-ff` flag have for `git merge`?
  4. When would you use the different git merge strategies?
  5. What’s the difference between ‘git merge’ and ‘git rebase’?
  6. Git – how to force merge conflict and manual merge on selected file
  7. What’s the best visual merge tool for Git? [closed]
  8. Git: ignore some files during a merge (keep some files restricted to one branch)
  9. Git merge reports “Already up-to-date” though there is a difference
  10. Can I make fast forwarding be off by default in git?
  11. Prevent commits in master branch
  12. How do I merge changes to a single file, rather than merging commits?
  13. How does ‘git merge’ work in details?
  14. Merge changes from remote github repository to your local repository
  15. git merge: Removing files I want to keep!
  16. How do I use `git rebase -i` after `git merge` without messing things up?
  17. Making Git retain different section content between branches
  18. Git: Merge to master while automatically choosing to overwrite master files with branch
  19. How to identify conflicting commits by hash during git rebase?
  20. What Git branching models work for you?
  21. How to “git show” the diffs for a merge commit?
  22. Git: How can I find a commit that most closely matches a directory?
  23. How to rebase one Git repository onto another one?
  24. What to do with branch after merge
  25. Tell git not to merge binary files but to choose
  26. What is the difference between git am and git apply?
  27. How can I visualize per-character differences in a unified diff file?
  28. How to apply `git diff` patch without Git installed?
  29. How to apply a Git patch to a file with a different name and path?
  30. git merging branches in a bare repository

Leave a Comment