git merge --squash is a Git command used to merge multiple commits from one branch into a single commit on another branch. This command is particularly useful when merging a feature branch into the main branch, as it keeps the commit history of the main branch clean and manageable.
Specifically, when you run git merge --squash feature-branch, Git gathers all changes from the feature-branch and places them as a new set of uncommitted changes in the working directory. This allows you to review or further adjust the changes before committing.
Use Case Example
Suppose you develop a new feature on the feature-branch, which has multiple small incremental commits. These commits are useful during development as they help save progress and understand the development history. However, when preparing to merge this new feature into the main branch, you might not want to bring all these small commits into the main branch, as they could complicate the commit history and make it difficult to manage.
In this case, you can use git merge --squash to consolidate all changes from the feature-branch into a single commit, then merge this single commit into the main branch. This approach not only maintains the main branch as clean and manageable but also preserves the integrity of the feature and the context of related changes.
Command Steps
- Switch to the target branch you want to merge into:
bash
git checkout main - Perform the merge with squash:
bash
git merge --squash feature-branch - Review the merged changes, confirm they are correct, and commit:
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git commit -m "Add new feature with squash merge"
This process enables you to merge a set of changes into a single commit, helping to maintain a concise commit history.