rebase.md

Rebasing a Feature Branch (feature-branch-name) onto a Release Branch (release-branch-name)

This document outlines the process of rebasing a feature branch (feature-branch-name) onto a release branch (release-branch-name) when the release branch has received new merges. This is a common scenario in collaborative development, and rebasing helps maintain a clean project history.

Why Rebase?

When you branch off of another branch (like release-branch-name), you create a separate line of development. As other pull requests (PRs) are merged into release-branch-name, the history of your feature-branch-name branch diverges. Rebasing helps in the following ways:

• Diverged History: Your feature-branch-name branch's history becomes different from release-branch-name as others merge their work.
• Cleaner History: Rebasing creates a linear project history, making it appear as if you started your work after the latest changes were merged into release-branch-name.
• Avoiding Merge Commits: Without rebasing, merging your branch would create a merge commit. While not inherently bad, too many merge commits can make the project history harder to follow.
• Conflicts: Rebasing allows you to resolve potential merge conflicts in advance, before the actual merge.

What Rebasing Means

Rebasing feature-branch-name onto release-branch-name involves these steps:

1. Rewinding: Git temporarily "undoes" the commits you made on feature-branch-name.
2. Updating Base: It moves the base of your feature-branch-name branch to the latest commit on release-branch-name.
3. Replaying: It reapplies your commits on top of the updated release-branch-name.

How to Rebase and Merge

Here's a step-by-step guide:

1. Checkout feature-branch-name:

   git checkout feature-branch-name

2. Fetch the Latest Changes:

   git fetch origin release-branch-name

   This updates your local copy of release-branch-name with the latest changes from the remote repository.

3. Rebase onto release-branch-name:

   git rebase origin/release-branch-name

   This rebases your feature-branch-name branch onto the latest release-branch-name.

4. Resolve Conflicts (If Any):

   • If conflicts occur, Git will pause the rebase and indicate the conflicted files.

   • Resolve Manually:

     1. Open the conflicted files in your editor.

     2. Edit the files to resolve the conflicts.

     3. Stage the resolved files:

        git add <conflicted_file>

     4. Continue the rebase:

        git rebase --continue

   • Abort (If Needed): If you need to abort the rebase, use:

     git rebase --abort

5. Force Push (Since You Rebased):

   • Important: Rebasing rewrites history, so you'll need to force push.

   • Caution: Only do this if you're the only one working on feature-branch-name. If others are collaborating, force pushing will cause them problems.

   • Safer Force Push:

     git push origin feature-branch-name --force-with-lease

     --force-with-lease is safer than --force. It only force pushes if the remote branch is in the state you expect.

6. Create or Update Your PR:

   • If you haven't already, create a pull request to merge feature-branch-name into release-branch-name.
   • If a PR exists, the force push will update it with the rebased changes.

7. Merge the PR:

   • Once approved, merge the PR. Since you rebased, it should be a "fast-forward" merge, moving the release-branch-name pointer forward.

Important Considerations

• Communication: If working on a team, inform your team members before rebasing feature-branch-name to avoid confusion.

• Force Push: Use force pushing cautiously. It can cause issues if others are working on the same branch.

• Backup: Create a backup branch before rebasing if you're unsure:

  git branch feature-branch-name-backup feature-branch-name

• Pull before rebase: Before rebasing, it's a good practice to pull the latest changes from the release-branch-name branch to make sure you're rebasing onto the most up-to-date version.

  git checkout release-branch-name
  git pull origin release-branch-name
  git checkout feature-branch-name
  git rebase origin/release-branch-name

Summary

Rebasing is a valuable tool for maintaining a clean Git history. In this case, it's the recommended way to handle the divergence between your branch and release-branch-name. Remember to be careful with force pushing and to communicate with your team.