Squashing Commits Together in Git

How can you squash multiple previous commits together into a single commit in a Git repository?

You can squash multiple previous commits into a single commit using git reset and git merge --squash. Here’s how to do it:

1. Stash Uncommitted Changes (optional but recommended): git stash
2. Reset to the Desired Commit:
   Reset your branch to the commit before the ones you want to squash. Replace 3 with the number of commits to squash: git reset --hard HEAD~3
3. Squash the Commits:
   Use git merge --squash to squash the commits. The HEAD@{1} argument refers to the commit you were at just before the git reset command: git merge --squash HEAD@{1}
4. Create a New Commit:
   Create a new commit with the combined changes: git commit This will open your configured commit message editor with a commit message containing details of the squashed commits. You can edit this message to summarize the changes.
5. Push the Squashed Commit:
   Push the squashed commit to the remote repository. If the commits you squashed have already been pushed to the remote, you will need to force push to rewrite the history: git push --force
6. Apply Stashed Changes (if you stashed changes in step 1):
   git stash pop

Detailed Steps and Commands

1. Stash Uncommitted Changes: git stash This command saves your uncommitted changes and cleans your working directory.
2. Reset to the Desired Commit: git reset --hard HEAD~3 This moves your branch pointer back by 3 commits. Adjust the number based on how many commits you want to squash.
3. Squash Commits: git merge --squash HEAD@{1} This stages all changes from the last 3 commits as a single change.
4. Create a New Commit: git commit This opens your commit editor (usually Vim or vi) with a pre-filled message detailing the squashed commits. Edit this message to summarize the combined changes. If using Vim, press i to enter Insert Mode, edit the message, press Esc to exit Insert Mode, and type :wq to save and quit.
5. Force Push to Remote: git push --force This command updates the remote repository, rewriting the history with your squashed commit.
6. Apply Stashed Changes:
   git stash pop
   This restores your stashed changes to your working directory.

Summary

By following these steps, you can effectively squash multiple commits into a single commit and update your remote repository, ensuring a cleaner and more concise commit history.