Git & GitHub - Squashing Commits

How to squash commits in Git

Squashing commits in Git involves combining multiple commits into a single commit. This can simplify the commit history and make it easier to manage. This guide covers how to squash commits effectively using interactive rebase and other techniques.

Squashing Commits Using Interactive Rebase

Step 1: Start an Interactive Rebase

Use the git rebase -i command followed by the commit hash or HEAD~n to specify the range of commits you want to squash:

# Example: Start an interactive rebase for the last 3 commits
$ git rebase -i HEAD~3
                

Step 2: Edit the Rebase Todo List

In the interactive rebase editor, replace pick with squash (or s) for the commits you want to squash into the previous commit. The first commit should remain as pick:

pick abc123 First commit
squash def456 Second commit
squash ghi789 Third commit
                

Step 3: Save and Exit the Editor

After editing the rebase todo list, save and exit the editor. Git will proceed with squashing the commits.

Step 4: Edit the Commit Message

Git will open a new editor window to combine the commit messages. Edit the combined commit message as needed, save, and exit the editor:

# Example combined commit message
First commit

Additional details from second commit
Additional details from third commit
                

Step 5: Complete the Rebase

Git will complete the rebase and apply the squashed commit to your branch. Verify the changes using git log:

# Verify the commit history
$ git log
                

Squashing Commits During a Merge

You can also squash commits during a merge by using the --squash option:

# Example: Squash and merge a feature branch into main
$ git checkout main
$ git merge --squash feature-branch

# Commit the squashed changes
$ git commit -m "Merged feature-branch with squashed commits"
                

Best Practices

Follow these best practices when squashing commits:

• Squash Before Pushing: Squash commits before pushing to a shared repository to avoid conflicts.
• Write Clear Commit Messages: Write clear and concise commit messages that describe the combined changes.
• Use Interactive Rebase for Editing History: Use interactive rebase to squash, edit, or reorder commits as needed.

Summary

This guide covered how to squash commits in Git, including using interactive rebase, squashing during a merge, and best practices. Squashing commits helps to maintain a clean and readable commit history, making it easier to manage and review changes.