Feature: disable line matching in split diffs

[barrettruth]

Prerequisites

• I have searched for duplicate or closed feature requests
• I have read the contributing guidelines

Proposal

Add an option to render split diffs without pairing deleted and added lines into the same row.

Proposed API:

splitLineMatching?: "paired" | "none"

Example patch:

@@ -1,2 +1,2 @@
 const value = getOldValue()
-return oldValue + 1
+return getNewValue(input) + 1

Current paired split layout:

old new │ old side               │ new side
2   2   │ - return oldValue + 1  │ + return getNewValue(input) + 1

With splitLineMatching: "none":

old new │ old side               │ new side
2       │ - return oldValue + 1  │
    2   │                        │ + return getNewValue(input) + 1

Motivation and context

I can't exactly recall where I've seen this diffing mode, but I like it/use it. The closest precedent is Gitea/Forgejo. Gitea describes this as "matching up added and deleted lines" in split diffs, and moved that matching from client-side JS into the renderer in go-gitea/gitea#16775..

Diff2Html exposes a similar concept directly as matching: 'lines' | 'words' | 'none'.

[amadeus]

Interesting, wouldn't unified essentially be a better way to run this flow if additions/deletions aren't side-by-side?

[barrettruth]

Yes - if by that you mean there's a bunch of empty column-space in the cases where there's a bunch of non side-by-side diffs.

It just provides some clarity in the cases where there are.

Thanks for the response, not sure how to help here 😅