Basic Git Series: Understanding Git Rebase

Overview

Git rebase is an alternative to merging that rewrites commit history to create a cleaner, more linear project history. Instead of creating a merge commit, rebasing moves or combines a sequence of commits to a new base commit.

Steps

1. Update your local main branch:

git checkout main
git pull

2. Switch to your feature branch:

git checkout feature-branch

3. Rebase your branch onto the latest main:

git rebase main

4. If there are conflicts, resolve them:

   • Edit the conflicted files
   • Add the resolved files: git add <filename>
   • Continue the rebase: git rebase --continue
   • (To abort the process: git rebase --abort)

5. Push your changes (requires force push if the branch is already on remote):

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

Common Issues

• Conflicts during rebase: Similar to merge conflicts, you’ll need to resolve them manually
• Lost commits: Rewriting history can cause commits to be lost if not done carefully
• Force push dangers: Using --force can overwrite others’ changes; use --force-with-lease instead

Additional Notes

• Golden rule of rebasing: Never rebase branches that others are working on
• Use interactive rebasing to clean up your commits before sharing:

  git rebase -i HEAD~3  # Rebase the last 3 commits
  

• Interactive rebase options:
  • pick: Keep the commit as is
  • reword: Edit the commit message
  • squash: Combine with previous commit
  • fixup: Combine with previous commit, discard the message
  • drop: Remove the commit

When to Use Rebase vs. Merge

• Use rebase when:

  • You want a clean, linear history
  • You’re working on a feature branch that only you use
  • Before submitting a pull request, to incorporate latest changes

• Use merge when:

  • You want to preserve the complete history
  • You’re working on a shared branch
  • You want to clearly show where a feature branch was integrated