JAI: Diff Editor (lite-diff)
100% AI Code · Human Reviewed
Working with AI assistants like Claude or ChatGPT? Tired of manually applying code patches?
This extension brings unified diff format to your IDE workflow. Apply AI-generated patches with preview, automatic backups, and drift detection.
- Before: Copy patches from AI chat → Manually find and edit each location → Hope nothing breaks
- After: Paste lite-diff patch → Preview changes in VS Code diff viewer → Apply with one click
Features
- In-file edits — Replace, delete, insert with familiar unified diff syntax
- Insert at file start/end — Use
@@ BOF and @@ EOF for file start/end
- Boundary blocks — Delete ranges between two marker lines using
...
- Global options — Ignore whitespace, blank lines, apply to all matches
- Preview mode — See exact changes in VS Code diff viewer before applying
- Multi-file support — Process multiple files in a single patch
- Automatic backups — Every change creates a backup in
.ldiff/ directory
Quick Start
- Open Command Palette (
Ctrl/Cmd+Shift+P)
- Run
JAI: Diff Editor (lite-diff)
- Paste your lite-diff patch
- Review changes in diff viewer, then apply
Syntax Guide
Basic Edit
--- file.txt
+++ file.txt
@@
context line (unchanged)
-old line
+new line
Insert at File Start
--- file.txt
+++ file.txt
@@ BOF
+first line
+second line
Insert at File End
--- file.txt
+++ file.txt
@@ EOF
+last line
Note: After @@ BOF and @@ EOF only + lines are allowed. Context ( ) or deletion (-) lines will cause error E411.
Delete Range (Boundary Block)
--- file.txt
+++ file.txt
@@
-start boundary
...
-end boundary
+replacement
Deletes everything from "start boundary" to "end boundary" inclusive, then inserts replacement.
Rules for boundary blocks:
... cannot appear at the start or end of the block- Two
... in a row without - line between them are forbidden
- Each boundary must have
- lines on both sides
Global Options
Add at the beginning of your patch, before any diff block:
--ignore-space-at-eol
--ignore-blank-lines
--- file.txt
+++ file.txt
@@
context line
-old line
+new line
| Option |
Description |
--ignore-space-at-eol |
Ignore trailing whitespace at end of lines |
--ignore-space-change |
Ignore changes in whitespace quantity (but not presence) |
--ignore-blank-lines |
Ignore blank lines when matching context |
--ignore-all-space |
Ignore all whitespace differences |
--apply-all-matches |
Apply hunk to all occurrences (single hunk only) |
Important Rules
- All structural elements must begin at the first position (no indentation):
---, +++, @@, -, +, (context), ..., #, --
- No blank lines allowed inside hunk body (from
@@ to the next @@ or end of diff block)
- Comments start with
# at the first position on a separate line
- Preview creates directories
.ldiff/<TIMESTAMP>/original/ and .ldiff/<TIMESTAMP>/preview/
Common Errors
| Error |
Cause |
Solution |
| E410 "No match found" |
Context doesn't match file |
Verify exact line match or use --ignore-* options |
| E401 "Invalid prefix" |
Indentation before -/+/ |
Remove leading spaces/tabs |
| E402 "Blank line inside hunk" |
Empty line in hunk body |
Remove or use prefix for empty context |
| E411 "Invalid content after BOF/EOF" |
Non-+ line after @@ BOF/EOF |
Use only + lines after BOF/EOF |
| E304 "Multiple hunks with --apply-all-matches" |
--apply-all-matches with >1 hunk |
Split into separate diff blocks |
| E724 "Drift detected" |
File changed after preview |
Re-run preview before applying |
Configuration
| Setting |
Default |
Description |
diffEditor.verboseLogging |
false |
Enable verbose logging for debugging |
diffEditor.backupLimit |
5 |
Max backup packages to keep (0 = only active) |
Contributing
Found a bug or have a feature request? Please open an issue on GitHub.
License
This extension is proprietary software. You may use and distribute it freely in its unmodified form, but modifications are not permitted. See LICENSE file for details.
🚀 Created by Claude Opus 4.5, ChatGPT 5 Pro
