Merging Branches
Once you have multiple branches, you often need to combine changes from one branch into another. This is called merging.
1. Merge a Branch into Current Branch
git merge <branch>
Description: Integrates changes from the specified branch into your current branch.
- Always commit or stash your changes before merging.
Example:
git checkout main
git merge feature-login
- If there are no conflicts, the branches are combined automatically.
2. Handling Merge Conflicts
Description: If Git cannot automatically merge changes, it will mark conflicts in files.
- You need to edit the files manually, then stage and commit the resolved changes.
Example:
# Edit conflicting files
git add <file>
git commit -m "Resolve merge conflicts"
3. Fast-Forward Merge
git merge <branch> --ff-only
Description: Only performs a merge if Git can do a fast-forward merge (no divergent changes).
- Prevents creating unnecessary merge commits.
Example:
git merge feature-login --ff-only
4. Merge with a Commit
git merge <branch> --no-ff
Description: Forces Git to create a merge commit even if a fast-forward merge is possible.
- Useful for keeping a clear branch history.
Example:
git merge feature-login --no-ff
5. Rebase a Branch
git rebase <branch>
Description: Moves your current branch commits on top of the specified branch.
- Keeps history linear, unlike merge which can create extra commits.
- Conflicts are resolved similarly to merge conflicts.
Example:
git checkout feature-login
git rebase main
- If conflicts occur:
# Resolve conflicts in files
git add <file>
git rebase --continue
- To cancel the rebase at any time:
git rebase --abort
Merge vs Rebase
Merge and Rebase are two ways to integrate changes from one branch into another.
-
Merge:
- Combines branches into one commit.
- Preserves full branch history.
- Can create a “merge commit” even if branches could fast-forward.
-
Rebase:
- Reapplies commits on top of another branch.
- Creates a linear history, making it cleaner.
- Changes the commit history, so avoid rebasing shared branches.
When to use:
- Use merge when you want to preserve the branch history.
- Use rebase when you want a clean, linear history before pushing or merging.
Summary of Merge Commands
| Command | Purpose |
|---|---|
git merge <branch> | Merge the specified branch into current branch |
git merge <branch> --ff-only | Merge only if a fast-forward is possible |
git merge <branch> --no-ff | Force a merge commit even if fast-forward possible |
git rebase <branch> | Reapply commits on top of another branch (linear history) |
| Conflict resolution | Edit files manually, stage, and commit |
Next, you’ll learn how to undo changes in the repository.