Git patch workflow

Skill cxcscmu/SkillLearnBench/skills/b1-one-shot-claude-haiku-4-5/fix-security-bug/git-patch-workflow

[COLM'26] SkillLearnBench is the first benchmark for evaluating continual learning methods that automatically generate agent skills.

Install

npx -y skills add cxcscmu/SkillLearnBench --skill git-patch-workflow

Assembled from the repository path, not quoted from the project. Check it against their README if it does not work.

What its author says it does

Copied from the file, not written here

Creating, managing, and applying unified diff patches with Git for source code modifications.

SKILL.md

2.3 KB, as published. Nobody here has run it

Git Patch Workflow

Creating Patch Files

Method 1: From Unstaged Changes

cd /path/to/repo
git diff path/to/file.java > /path/to/patch/fix.patch

Method 2: From Staged Changes

git diff --cached > /path/to/patch/fix.patch

Method 3: From Commits

# Create patch from last N commits
git format-patch -N HEAD

# Create patch from specific commit
git show COMMIT_HASH > /path/to/patch/fix.patch

Patch File Structure

A unified diff patch looks like:

--- a/original/path/file.java
+++ b/modified/path/file.java
@@ -10,5 +10,6 @@ class MyClass {
     // context line
-    old code here
+    new code here
     // context line

Key components:

--- prefix: original file
+++ prefix: modified file
@@ markers: line numbers and context
- prefix: removed lines
+ prefix: added lines
No prefix: context lines

Applying Patches

Basic Application

cd /path/to/repo
patch -p1 < /path/to/patch/fix.patch

With Error Handling

# Dry-run to test application
patch -p1 --dry-run < /path/to/patch/fix.patch

# Apply with strict checking
patch -p1 < /path/to/patch/fix.patch

# Apply with less strict checking
patch -p0 < /path/to/patch/fix.patch

Best Practices

Use Git Format: Create patches via git diff or git format-patch for consistency
Include Context: Ensure adequate context lines (3+ lines around changes)
Test Patches: Always dry-run before applying to ensure compatibility
Modular Patches: Create separate patches for logically independent changes
Clear Names: Name patches descriptively (e.g., fix-javascript-security-bypass.patch)
Document Changes: Include explanation of what the patch fixes

Verifying Application

# Check if patch was applied
git status
git diff HEAD

# Verify specific file was patched
git show HEAD:path/to/file.java | grep "your fix"

Multiple Patches

For multiple related patches:

# Create patches in order
git diff HEAD~2 HEAD~1 > patch1.patch
git diff HEAD~1 HEAD > patch2.patch

# Apply in sequence
patch -p1 < patch1.patch
patch -p1 < patch2.patch