How do I make Vim diff ignore whitespace and use patience algorithm for clearer hunks?

Explanation

When whitespace-only churn and noisy line matching make diffs hard to review, tuning diffopt can dramatically improve signal. Adding iwhite tells Vim to ignore whitespace differences, while algorithm:patience improves hunk alignment for reordered or refactored code. This is especially helpful in large formatting commits where default diff output becomes fragmented.

How it works

:set diffopt+=iwhite,algorithm:patience

• :set diffopt+=... appends settings without removing your existing diffopt values
• iwhite ignores whitespace-only differences in diff mode
• algorithm:patience switches to a diff strategy that tends to produce more stable hunks on source code

Because this modifies an option, use :setlocal if you only want it in the current window, or put the setting in your vimrc for a persistent default.

Example

Imagine a file where indentation changed and a helper block moved:

-    if (ready) {
-        run_task();
-    }
+if (ready) {
+  run_task();
+}

... helper function moved lower in file ...

With default diff settings, Vim may show extra churn from indentation and split movement into less useful hunks. After enabling iwhite,algorithm:patience, the diff focuses more on semantic edits and often groups moved logic into clearer chunks.

Tips

• Check active values with :set diffopt?
• Revert quickly with :set diffopt-=iwhite diffopt-=algorithm:patience
• Combine with :diffupdate after changing options in an existing diff session