I've added support for diffing multiple files at once to Diffest. While this example is not of a huge code base, the code-aware diff correctly tracks code that was moved between files. &diffest

I'm now grouping and highlighting related changes with surrounding context if possible. &diffest

You might be wondering why I picked Python for the first few test cases. The answer is this optional comma featured in test cases 04 and 05. &diffest

If someone is trying to sneak a change into the middle of a big reformatting, a code-aware diff can tell you exactly what's going on.
(In this jam, I'm exploring what a code-aware diff tool could do for you. Past updates and more info at https://handmade.network/p/366/diffest/, &diffest)

And with that the fourth box, "Code-Aware Diff", is filled. What's that, it doesn't look very spectacular? Well, there haven't been any spectacular changes here, have there? &diffest

I haven't quite filled that fourth box yet but I've made a lot of progress. I'm parsing both files into a syntax tree which I'll then use to calculate a diff between those files. This syntax tree is a combined abstract and concrete syntax tree: The black nodes form the AST and the gray nodes come from the CST and fill in the gaps between the nodes of the AST. The content in quotes comes directly from the source code while anything else is tree-types and structure. The grey nodes are actually two different types: necessary punctuation and optional whitespace; they are not differentiated in this visualization. Because of its structure and because it's neither an AST nor a CST I'm calling it an "expandable syntax tree" or EST (which then brings us to "diffEST" 😛 ). Up next: Fill that fourth box. &diffest

I spent the morning finalizing ThePlan™ and creating the first dozen test cases. Then I built a way to visualize the diffs I'm about to produce and hooked up a regular text diff (as available in Darke) for comparison. Up next: Fill that fourth box.
(In this jam, I'm exploring what a code-aware diff tool could do for you. Past updates and more info at https://handmade.network/p/366/diffest/, &diffest)

I'm in.
Despite our best efforts, the vast majority of source code is still in plain text. Lots of tools operating on source code only work with that plain text. Advanced tools however, like the Language Server in your favorite IDE, use this plain text as a starting point to build up rich, complex, and ultimately incredibly useful data structures in which your code lives. These tools understand your code, in many cases better than you do yourself. (And way-too-often they need to be restarted because they manage to run themselves into some infinite loop or whatever but I digress.)
A tool that is at least slightly aware of the code you have written could compare two states of the same code base and:
1️⃣ Look past changes in formatting to focus on what's actually relevant.
2️⃣ Group related changes so renaming a constant is one change instead of several dozen.
3️⃣ Examine the entire code base instead of handling every file individually.
4️⃣ Track where code came from and where it was moved to.
5️⃣ Present the entirety of the changes in a sensible and ordered way.
6️⃣ And finally, figure out what changes weren't even made.
And that's what I'll be exploring during the Visibility Jam.
diff, differ, &diffest

(originally posted on 2023-03-04 in #jam)