blame: respect .git-blame-ignore-revs automatically

[Ethan0456]

Introduction

Hi, I'm Abhijeet (Ethan0456), and this is my first contribution to the Git project. I currently work as an ML Engineer at an early-stage startup, and I’m excited to contribute to this open-source project.

Why the Change?

I came across this enhancement request on the bug tracker and found it beginner-friendly, making it a great opportunity for me to get familiar with the Git codebase. The ability for git blame to automatically respect the .git-blame-ignore-revs file is something that can streamline workflows for many users, and I felt it would be a valuable addition.

Feedback

While I’m confident in the changes made to builtin/blame.c and the new test case in t/t8015-blame-ignore-revs.sh, I welcome any feedback or suggestions to improve both my code and approach. I’m eager to learn from the community and improve where needed.

Community Need

There is precedent for this functionality in other projects:

• Chromium, which powers many popular browsers, uses .git-blame-ignore-revs to simplify the blame process by ignoring non-functional changes.
• Rob Allen's blog post discusses the need for ignoring revisions with git blame, and a commenter specifically suggests that it would be helpful if Git automatically respected .git-blame-ignore-revs.

I hope this change aligns with community needs and improves the git blame experience for users.

[gitgitgadget]

Welcome to GitGitGadget

Hi @Ethan0456, and welcome to GitGitGadget, the GitHub App to send patch series to the Git mailing list from GitHub Pull Requests.

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[nasamuffin]

/allow

[nasamuffin]

Please note the comments I made in Discord before you send this to the mailing list. Happy hacking:)

[gitgitgadget]

User Ethan0456 is now allowed to use GitGitGadget.

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[Ethan0456]

Thank you for your feedback! I really appreciate your suggestions and will make sure to incorporate them before sending it to the mailing list.