cleanDiff

Compact git diff as structured JSON

Go Development GitHub

Git diff output as structured JSON with only changed lines. No context padding by default. Use for token-efficient diff review in AI workflows.

Features

Structured JSON output with changed lines grouped by file
Zero context lines by default (configurable)
Stat-only mode for file-level overview
Filter by specific files
Support for staged changes and commit ranges

Install

go install github.com/hegner123/cleanDiff@latest

The Problem: git diff is verbose and unstructured

$ git diff HEAD~1
diff --git a/main.go b/main.go
index abc1234..def5678 100644
--- a/main.go
+++ b/main.go
@@ -10,7 +10,7 @@ func main() {
     ctx := context.Background()
     cfg := loadConfig()
     db := connectDB(cfg)
-    srv := newServer(db)
+    srv := newServer(db, cfg.Logger)
     srv.Start(ctx)
 }

# 7 lines of context for 1 changed line.
# Multiply by 20 files = massive token waste.

Solution

$ cleanDiff --cli --ref HEAD~1

Output

{"summary":{"files_changed":1,"insertions":1,"deletions":1},"files":[{"path":"main.go","status":"modified","hunks":[{"old_start":13,"new_start":13,"lines":["-    srv := newServer(db)","+    srv := newServer(db, cfg.Logger)"]}]}]}

Comparison

Metric	Value
Context reduction	Zero padding by default (git diff uses 3 lines)
Output format	Structured JSON vs raw unified diff
Filtering	By file path, staged only, commit range