alt Hacker NewsShow HN: OmniDiff – Opensource, super fast, content aware Git difftool, in Rust
I have been researching what the ultimate diff tool would look like, based on actual diffs in open source repositories.
OmniDiff can diff: code (25 languages), config, images, PDFs, archives, cursors, fonts...
It's fast. It can diff C++ files of tens of thousands of lines in under 100ms, on a 2023 ThinkPad T14s.
It's open source. AGPLv3.
It's based on real diffs. I looked at the 7400 repositories that are listed in Gentoo packages, sampled 2000 diffs and solved them manually to get a good understanding of what is needed, before putting together the diff pipelines for each content type. Incidentally, this also forms the basis of the CI pipeline, so the robustness of the codebase is quite high.
I'm still developing it. It's v0.3.0 at this time. But I have been using it daily as my git difftool for months now, and it works well.
AI Disclosure: Yes, I do use AI. No, I do not vibecode.
Comments
Really well done, I like this a lot. It produces much more minimal diffs than other tools I've tried.
One feature I miss from difftastic is showing diffs side-by-side on wide terminals, and unified when narrow.
Older submission: https://news.ycombinator.com/item?id=49891989
How does it compare with diffstatic?
You have a good core idea here. You're pretty much killing your project in infancy with the AGPL+donation license model. Meanwhile, some other projects will take the core idea of "language aware differ" and release BSD, and one of those will win, including perhaps making it into git/future version controls.
IMO, you should seek to make this a standard that wins, and hopefully other opportunities that come will be where you make commercial hay. My unsolicited 2c.
How is it better or worse compared to https://github.com/dandavison/delta ?
[flagged]
Something nobody asked for with licenses nobody wants to use. Project is dead before it started
Delta has a really nice way to show diffs with its diff-so-fancy mode, it's more similar to GitHub's UI where not only the line is colored up differently but there's a different shade of color to highlight the characters.
There's a screenshot and video of it here that I wrote a while back: https://nickjanetakis.com/blog/awesome-git-diffs-with-delta-...
In OmniDiff's readme and web version I didn't see a way to do that.
In a different comment you mentioned OmniDiff is much better than Delta and you mentioned "About a third of diffs are significantly better.". Can you provide some examples of these? I've never seen Delta fail a diff.
Also Delta has a package for Arch in its official repos. For folks who just want a "it works" experience, that's a pretty big win. With Delta the same package can be installed in the same way on Debian, Arch and macOS with Brew using standard package managers. With OmniDiff, there's 3 different ways to install it (manual deb package on Debian, manual package compile on Arch and brew install on a Mac). Just something to think about, as someone who has public dotfiles that work in those 3 environments, I'd skip OmniDiff based on this alone.