How to Squash Commits in Git After Push

Introduction

This guide explains how to combine, or squash, multiple Git commits into a single commit after they have already been pushed to a remote repository.

Rebasing pushed commits changes the repository history. Do not use this on a shared branch if anyone else may have based work on its current history, because rewriting it can disrupt their work.

The short version

Squash the last four commits with:

git rebase -i HEAD~4

Here, ~4 selects the last four commits.

Then update the remote branch safely:

git push --force-with-lease origin <branch>

Steps

1. Start an interactive rebase

Open a terminal and run the rebase command. Replace N with the number of commits you want to review, such as 4 for the last four commits.

git rebase -i HEAD~N
# Or rebase commits after a specific upstream point
git rebase -i origin/master

2. Mark commits to squash

Your default text editor will open with a list of commits:

pick 1fc6c95 New feature A
squash 6b2481b Fix typo in A
squash dd1475d Fix bug in A

Keep the first commit as pick. Change the following commits that you want to combine from pick to squash, or s for short. Save and close the file.

3. Update the commit message

A new editor window will open so you can edit the commit message for the combined commit. Change it as needed, then save and close the file.

4. Force-push the changes

Since the history has been rewritten, a standard push may be rejected. Use --force-with-lease so the push fails if the remote branch has changed since you last fetched it:

git push --force-with-lease origin <branch>

Source: Stack Overflow.