unified-diff-generation

Generate patch-compatible unified diffs with a/ and b/ prefixes.

4|2|Updated Jan 11, 2026
One-click install
npx skills add https://github.com/nick-orton/vybz --skill unified-diff-generation
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: unified-diff-generation
Source: https://github.com/nick-orton/vybz/tree/main/src/vybz/library/skills/unified-diff-generation
Command: npx skills add https://github.com/nick-orton/vybz --skill unified-diff-generation

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This skill enables the precise generation of patch-compatible unified diffs (diff -u), ensuring proper headers, context, and formatting to keep patches portable and applyable with standard tools.

Core Features & Use Cases

  • Produce unified diffs with mandatory a/ and b/ prefixes
  • Enforce 3-line context per hunk
  • Handle new/deleted files with /dev/null representations
  • Validate headers, whitespace, and line counts for patch compatibility

Quick Start

Generate a patch by producing a unified diff (diff -u) with proper a/ and b/ prefixes, three-context hunks, and correct header counts, then validate it by applying with patch -p1.

Frequently Asked Questions about unified-diff-generation

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I generate a unified diff that applies cleanly with patch -p1?▼

To generate a unified diff compatible with patch -p1, you need mandatory a/ and b/ file path prefixes, exact 3-line context per hunk, and accurate header line counts. This ensures the patch remains portable and applyable across source trees.

What is the correct format for a unified diff when creating a patch?▼

A correct unified diff format requires a/ and b/ path prefixes, three lines of surrounding context for each hunk, and proper /dev/null representations for new or deleted files. It must also preserve original indentation and final newline semantics.

How do I handle new or deleted files in a unified diff?▼

When handling new or deleted files in a unified diff, the absent file side should be represented using /dev/null. This maintains patch compatibility and ensures the file creation or removal applies correctly to the source tree.

Why does my generated patch fail to apply due to context mismatch?▼

Patch application failures often occur when a unified diff lacks the exact 3-line context rule, contains inaccurate header line counts, or alters original indentation. Enforcing proper formatting and whitespace validation resolves these compatibility issues.

Can I generate a unified diff for both small and large code changes?▼

Yes, you can generate patch-compatible unified diffs for both small and large changes. The process enforces correct headers, file path prefixes, and context rules across the entire diff regardless of the change size.

Does a unified diff need to preserve final newline semantics?▼

Yes, preserving final newline semantics is required when generating a unified diff. Maintaining exact whitespace, indentation, and newline characters ensures the patch validates correctly and applies without conflicts.