Git : Applying Diff from Pull Request to New Branch with a Single Commit

Efficient code collaboration is crucial for software development teams, and Git provides powerful tools to streamline this process. When working with pull requests, it's often helpful to review changes and apply them to a different branch while maintaining a clean commit history. In this blog post, we'll explore the steps to diff a Git pull request and apply those changes to a new branch with a single commit, promoting a more organized and concise development workflow.

When a pull request is created, it generates a diff that represents the changes made in the branch being merged. This diff includes additions, deletions, and modifications made to the codebase. Understanding the diff is crucial to selectively apply these changes to a new branch.

Here are steps to get diff from PR and to apply into new branch effectively:

Step 1: Fetch the Pull Request:

1. Start by cloning the repository or ensuring you have the latest changes by running git fetch origin.
2. Checkout the branch on which the pull request is based, using the command git checkout <pull_request_branch>. Replace <pull_request_branch> with the actual branch name.

Step 2: (Either  a OR b)
a - Generate a Diff:

1. To view the changes introduced in the pull request, use the command git diff origin/master...<pull_request_branch>.
2. Review the diff output to understand the modifications made in the pull request and the impact on the codebase.

b- Retrieving the Pull Request Diff:

1. Locate the pull request associated with the desired changes. Most code hosting platforms provide a web interface to view the diff. 
2. Retrieve the diff either by downloading it as a file or by copying the contents to your clipboard.

Step 3: Create a New Branch:

1. Create a new branch to apply the changes using the command git checkout -b <new_branch>. Replace <new_branch> with a descriptive name for the new branch.

Step 4: Apply the Diff:

1. Apply the changes from the pull request to the new branch using the command git apply -3 --stat <path_to_diff_file>. Replace <path_to_diff_file> with the path to the diff file generated in Step 2.
2. Verify that the changes have been applied correctly by running tests or reviewing the modified files.

Step 5: Stage and Commit the Changes:

1. Add the modified files to the staging area using git add .
2. Commit the changes with a meaningful commit message using git commit -m "Apply changes from pull request <pull_request_number>". Replace <pull_request_number> with the actual number of the pull request being applied.

Step 6: Push the New Branch:

1. Push the new branch to the remote repository using git push origin <new_branch>. This will make the changes available to others and facilitate further collaboration.

In conclusion, by following these steps, you can effectively diff a Git pull request, extract the changes, and apply them to a new branch with a single commit. This approach helps maintain a clean commit history, making it easier to track changes, review code, and collaborate with team members. Incorporating these practices into your workflow will enhance code collaboration, improve code quality, and streamline the development process..