Fix hunk drag to respect selected lines

[godnight10061]

Fixes #2513.

• Dragging a hunk now uses the selected line range (when present) instead of always using the full hunk.

Testing:

• Local (Windows):
  • pnpm prettier
  • pnpm lint
  • pnpm check
  • pnpm test
  • cargo fmt --check --all
  • cargo check --workspace --all-targets
  • cargo check --workspace --all-targets --features windows

Before/After:

after.mp4

before.mp4

[vercel]

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[Byron]

Thanks a lot for tackling this, this seems like something we really want fixed as it's surprising if the selection isn't respected.

There I wonder if the visualisation should also be indicating that it's just the selected lines that are dragged, it still looks like it's the entire hunk.

Meanwhile, let's also put it back into draft while there are conflicts. Maybe @mtsgrd or @Caleb-T-Owens can chime in to see if this generally the way to go in the frontend.

In the backend, I don't think any of the changes should be needed.

[mtsgrd]

Indeed, thanks for putting together a fix for this. It was never implemented, by reasonably should. I see you've just recently pushed some more commits, and there's a lint issue there.. but let me check this branch out in a couple of hours, and we'll get it merged as soon as possible. 🙏

[godnight10061]

@Byron @mtsgrd Thanks! I simply added a "selected lines" section right after the dragging hunk header. Would appreciate any UI ideas to make it even clearer.
Video:

dummyRepo.GitButler.Dev.2026-01-22.09-30-04.mp4

[Byron]

Wow, I am loving it! Now it's not surprising anymore and the info-box one is dragging around has just the right size and information.

Something that my eye found less pleasing was the line break for 'lines'. Maybe removing the selected would already do it?

@PavelLaptev would probably have some notes as well now.

[PavelLaptev]

@godnight10061 thank you for he PR!

I noticed that we can select lines to drag if the change is assigned or unassigned.
However, hunks in committed changes can also be draggable (see video).
To maintain consistency, we should provide the same functionality in all places where we can drag hunks.

Screen.Recording.2026-01-22.at.13.15.11.mov

[Byron]

Thanks a lot @PavelLaptev! Is this something that can be generalised in code so it's applied generically?
If not, then it would probably still make sense to take these changes one 'location' at a time to keep this PR small.

[PavelLaptev]

Thanks a lot @PavelLaptev! Is this something that can be generalised in code so it's applied generically? If not, then it would probably still make sense to take these changes one 'location' at a time to keep this PR small.

I’m not sure if this can be generalized, but I believe it should be, or the behavior will be inconsistent.

[PavelLaptev]

@Byron, as we discussed this offline, we can merge this. However, let’s not forget to implement the ability to drag hunk lines in other places where it’s possible to do so.