z-diff-cleaner

Remove formatting-only changes from git diffs before sending them to LLMs for code review.

Features

• Detect and remove whitespace-only changes
• Detect comment-only changes
• Detect quote style changes (safe cases only)
• Detect trailing comma changes (non-JSON)
• Detect optional semicolon changes with ASI safety checks
• Detect import reordering when the import set is unchanged
• Detect line-wrapping-only changes when tokens are unchanged

Install

npm i z-diff-cleaner

Usage

import { DiffCleaner } from 'z-diff-cleaner';

const cleaner = new DiffCleaner();

const diffText = `diff --git a/app.ts b/app.ts
@@ -1,2 +1,2 @@
-const a = 1;
+const a  =  1;`;

const result = cleaner.clean(diffText, {
  ignoreWhitespace: true,
  ignoreCommentChanges: true,
  ignoreQuoteChanges: true,
  ignoreTrailingCommas: true,
  ignoreOptionalSemicolons: true,
  ignoreImportReordering: true,
  ignoreLineWrappingChanges: true,
});

const cleanedDiff = cleaner.reconstruct(result.cleaned);
console.log(cleanedDiff);

Configuration

• ignoreWhitespace: Remove whitespace-only changes
• ignoreCommentChanges: Remove comment-only changes
• ignoreImportReordering: Remove import reordering when the set is unchanged
• ignoreLineBreaks: Remove line break changes
• ignoreLineWrappingChanges: Remove line-wrapping-only changes when tokens are unchanged
• ignoreQuoteChanges: Remove quote style changes when safe
• ignoreTrailingCommas: Remove trailing comma changes in non-JSON
• ignoreOptionalSemicolons: Remove optional semicolons when safe
• language: Language hint for future optimizations

Output

The clean API returns:

• original: Parsed diff files
• cleaned: Filtered diff files
• formatChanges: Detected formatting changes
• statistics: Summary of files and lines removed

Development

npm test
npm run lint
npm run typecheck

License

MIT License © Huali