How to squash multiple commits into a single commit?

Squashing Multiple Commits into a Single Commit

Squashing multiple commits into a single commit is a common Git operation that allows you to combine a series of related commits into a single, more meaningful commit. This is particularly useful when you have a series of small, incremental commits that you want to condense into a single, more coherent commit before pushing your changes to a remote repository or merging them into another branch.

Why Squash Commits?

There are several reasons why you might want to squash multiple commits into a single commit:

1. Cleaner Git History: Squashing commits can help keep your Git history clean and easy to understand, especially when working on a project with multiple collaborators. By consolidating related changes into a single commit, you can make the commit history more concise and easier to navigate.

2. Easier Debugging and Rollbacks: When you have a series of small, incremental commits, it can be difficult to pinpoint the exact change that introduced a bug or issue. By squashing these commits into a single, more meaningful commit, you can make it easier to debug and roll back changes if necessary.

3. Preparing for Pull Requests or Merges: Before submitting a pull request or merging your changes into another branch, it's often a good idea to squash your commits to ensure that your contribution is presented in a clear and organized manner.

How to Squash Commits

To squash multiple commits into a single commit, you can use the git rebase command. Here's a step-by-step guide:

1. Open a Terminal: Ensure that you are in the correct Git repository and on the branch where you want to squash the commits.

2. Identify the Commits to Squash: Use the git log command to review the commit history and identify the range of commits you want to squash.

git log --oneline

This will display a concise list of your commit history, making it easier to identify the commits you want to squash.

3. Start the Interactive Rebase: Use the git rebase -i command to start the interactive rebase process. You'll need to specify the commit hash of the commit that comes before the first commit you want to squash.

git rebase -i HEAD~3

In this example, HEAD~3 means that you want to rebase the last 3 commits.

4. Edit the Commit Messages: The interactive rebase will open a text editor, where you can modify the commit messages and choose how to handle each commit. The default editor is usually vim, but you can change this by setting the $EDITOR environment variable.

In the text editor, you'll see a list of your commits, with the oldest commit at the top. To squash the commits, change the word pick to squash (or s for short) for the commits you want to combine.

pick 1a2b3c4 Commit 1
squash 5e6f7g8 Commit 2
squash 9h0i1j2 Commit 3

5. Save and Close the Editor: Once you've made your changes, save the file and close the text editor. Git will then combine the specified commits into a single commit, and you'll be prompted to edit the new commit message.

6. Edit the Commit Message: In the text editor, you can now edit the combined commit message to make it more meaningful and descriptive.

7. Complete the Rebase: Save the commit message and close the text editor. Git will now complete the rebase process, and you'll have a single commit that represents the changes from the previous multiple commits.

Here's a Mermaid diagram that illustrates the squashing process:

By squashing multiple commits into a single commit, you can maintain a clean and organized Git history, making it easier to understand and work with your project's codebase.