> Learn how to streamline your pull request analysis using advanced Git diff techniques. This guide covers basic and advanced methods to focus on relevant code changes and improve your review process. [Git Documentation](https://git-scm.com/doc) # Git Diff for Pull Request Analysis As a developer, reviewing pull requests is a crucial part of the software development process. While platforms like GitHub and GitLab offer user-friendly interfaces for this task, sometimes we need a more tailored approach. This guide will show you how to leverage the power of `git diff` to analyze pull requests effectively and efficiently. ## Understanding the Basics of Git Diff Before diving into advanced techniques, let's cover the fundamental `git diff` commands for pull request analysis: 1. Ensure you're on the target branch (usually main): ```bash git switch main ``` 1. Fetch the latest changes: ```bash git fetch origin ``` 1. View changes between the current branch and the pull request branch: ```bash git diff origin/main...origin/feature-branch ``` 1. e.g. `origin/release` is the target branch, and `story/DX-16597` is the pull request branch. ```bash git diff origin/release...origin/story/DX-16597 ``` 1. For a concise summary of changes: ```bash git diff --stat origin/main...origin/feature-branch ``` 1. To see only changed file names: ```bash git diff --name-status origin/main...origin/feature-branch ``` These commands provide a solid foundation for pull request analysis, but they often include more information than necessary. ## Advanced Git Diff Techniques for Focused Analysis To overcome the limitations of standard `git diff` output, which often includes irrelevant files like `CHANGELOG.md` or `package-lock.json`, we can use a more refined approach: ```bash git fetch origin git diff origin/main...origin/feature-branch \ --unified=0 \ ':!CHANGELOG.md' \ ':!package-lock.json' \ ':!yarn.lock' \ ':!*.lock' \ ':!*.md' \ > pr_changes.txt ``` This command: 1. Fetches the latest changes 2. Compares the main branch to the feature branch 3. Shows only changed lines without context 4. Excludes specific files and file types 5. Outputs the result to a file > Review note: path exclusions should be deliberate. Lockfiles, migrations, documentation, and generated metadata can be security- or behavior-relevant and should not be hidden by default. Unmatched exclude pathspecs do not require deleting the pattern in normal modern Git usage. ## Customizing Your Git Diff Approach Pathspecs make the command adaptable, but every exclusion narrows the review evidence. You can easily modify the exclusion patterns to suit your project's needs. For example, to exclude all JSON files, add `:!*.json` to the list. ## Implementing the Advanced Git Diff Technique After running the advanced command, you'll have a `pr_changes.txt` file containing a focused diff of your pull request. You can: 1. Review the changes directly in this file 2. Share the file with team members for collaborative review 3. Use the content with AI tools for automated analysis without context limit concerns For a quick overview, use: ```bash head -n 50 pr_changes.txt ``` This displays the first 50 lines of the diff, giving you a snapshot of the changes. ## Conclusion Compare from the merge base, keep review-relevant files visible, and use the hosting platform's PR diff as a second view before approval.

1
2
3
4
5
6
7
8
9

git fetch origin
git diff origin/main...origin/feature-branch \
  --unified=0 \
  ':!CHANGELOG.md' \
  ':!package-lock.json' \
  ':!yarn.lock' \
  ':!*.lock' \
  ':!*.md' \
  > pr_changes.txt

1

head -n 50 pr_changes.txt