How do I tune Vim diff mode for more readable side-by-side hunks?

Explanation

Default diff behavior can look noisy on refactors where blocks move or indentation shifts. This diffopt combination improves readability by forcing vertical layout and choosing a diff strategy that better preserves meaningful structure. For large reviews, that often means fewer distracting hunks and clearer intent.

How it works

• vertical opens diff windows side-by-side instead of stacked, which is easier for line-by-line scanning
• algorithm:patience uses the patience algorithm, which tends to produce cleaner hunks when lines are reordered
• indent-heuristic biases matching toward indentation-aware boundaries so code blocks line up more naturally

You can apply this on demand before :diffthis, or set it once in your Vim config for a better default review experience.

Example

Given two versions of a function where inner blocks were moved and reindented, default diff may split the change into many small hunks.

Run:

:set diffopt+=vertical,algorithm:patience,indent-heuristic

Then start diff mode; the same change usually appears as fewer, more coherent hunks that are faster to review.

Tips

• You can inspect current settings with :set diffopt?.
• If you need maximum compatibility, append options incrementally and compare output on a real file pair.