jiangcang_vj/.cursor/skills/git-commit-analysis/reference.md

Git Commit Analysis Reference

Git Commands Reference

Basic Commit Inspection

# View commit summary
git show <hash> --stat

# View full diff
git show <hash>

# View commit message
git log -1 <hash> --pretty=format:"%s%n%n%b"

# View specific file in commit
git show <hash>:path/to/file

# View file before commit
git show <hash>^:path/to/file

# Compare with parent commit
git diff <hash>^..<hash>

Advanced Inspection

# View commit with context
git show <hash> -U10  # 10 lines of context

# View only specific file changes
git show <hash> -- path/to/file

# View commit tree
git show <hash> --name-status

# View commit with word diff
git show <hash> --word-diff

Analysis Depth Levels

Level 1: Surface Analysis

• Read commit message
• List changed files
• Summarize changes

Level 2: Code Analysis

• Read changed code sections
• Understand what changed
• Identify patterns

Level 3: Deep Analysis (This Skill)

• Read surrounding context
• Understand why changes were made
• Analyze design decisions
• Assess impact

Code Reading Strategies

Strategy 1: Top-Down

1. Read function/class definition
2. Read callers
3. Read implementation details

Strategy 2: Bottom-Up

1. Read changed code
2. Read related functions
3. Understand overall pattern

Strategy 3: Context-First

1. Read 50-100 lines before change
2. Read changed section
3. Read 50-100 lines after change
4. Understand full context

Common Change Patterns

Pattern: Variable Rename

• Usually simple but check all usages
• May indicate semantic change

Pattern: Function Extraction

• Check if extracted function is reused
• Understand abstraction level

Pattern: Condition Addition

• What edge case is being handled?
• Why wasn't it handled before?

Pattern: Data Structure Change

• Performance implications?
• API compatibility?

Analysis Questions Checklist

For each change, ask:

What Changed?

• What code was modified?
• What files were affected?
• What functions/classes changed?

Why Changed?

• What problem does this solve?
• What requirement drives this?
• What bug was fixed?

How Changed?

• What approach was used?
• Why this approach vs alternatives?
• What trade-offs were made?

Impact?

• Does this break existing code?
• Are tests updated?
• Is documentation needed?
• Performance implications?

Code Context Guidelines

Minimum Context

• Function changes: Include entire function
• Class changes: Include class definition
• File-level: Include imports and related functions

Recommended Context

• 50-100 lines before change
• 50-100 lines after change
• Related functions in same file
• Callers of changed functions

Extended Context (when needed)

• Related files that interact
• Similar patterns in codebase
• Historical context (previous commits)

Output Quality Standards

Code Snippets

• ✅ Include line numbers
• ✅ Show sufficient context (50-100 lines)
• ✅ Highlight key changes
• ✅ Include both before/after

Analysis Depth

• ✅ Explain "why" not just "what"
• ✅ Cover business and technical aspects
• ✅ Identify potential issues
• ✅ Suggest improvements if relevant

Structure

• ✅ Clear sections and subsections
• ✅ Use emojis for visual organization
• ✅ Code blocks properly formatted
• ✅ Links to related code when helpful