Operation: Analyze Commit Style

Purpose: Analyze recent commit history to learn the project's commit message style, conventions, and patterns.

Parameters

From $ARGUMENTS (after operation name):

• count:N - Number of commits to analyze (default: 50)
• branch:name - Branch to analyze (default: current branch)
• format:json|text - Output format (default: text)

Workflow

1. Validate Repository

# Check if in git repository
if ! git rev-parse --git-dir >/dev/null 2>&1; then
    echo "Error: Not in a git repository"
    exit 1
fi

# Check if has commits
if ! git log -1 >/dev/null 2>&1; then
    echo "Error: No commit history found"
    exit 1
fi

2. Execute Style Analysis Script

Invoke the style-analyzer.sh utility script:

./.scripts/style-analyzer.sh <count> <branch>

The script will:

• Fetch recent commits from git log
• Analyze commit message formats
• Calculate statistics (average length, type distribution, etc.)
• Detect conventional commits usage
• Identify common patterns

3. Process Analysis Results

The script returns JSON output with:

{
  "project_style": {
    "uses_conventional_commits": true,
    "conventional_commits_percentage": 87,
    "average_subject_length": 47,
    "subject_length_stddev": 8,
    "common_types": [
      {"type": "feat", "count": 45, "percentage": 35.4},
      {"type": "fix", "count": 38, "percentage": 29.9},
      {"type": "docs", "count": 20, "percentage": 15.7}
    ],
    "common_scopes": [
      {"scope": "auth", "count": 23, "percentage": 18.1},
      {"scope": "api", "count": 19, "percentage": 14.9},
      {"scope": "ui", "count": 15, "percentage": 11.8}
    ],
    "imperative_mood_percentage": 92,
    "has_body_percentage": 34,
    "references_issues_percentage": 67,
    "consistency_score": 85,
    "sample_commits": [
      "feat(auth): implement OAuth2 authentication",
      "fix(api): handle null pointer in user endpoint",
      "docs: update API documentation"
    ]
  }
}

4. Generate Recommendations

Based on analysis results, provide:

Style Recommendations:

• Conventional commits adherence level
• Recommended message format
• Typical subject line length
• Body usage patterns
• Issue reference patterns

Type Recommendations:

• Most commonly used types
• Type usage frequency
• Recommended types for new commits

Scope Recommendations:

• Commonly used scopes
• Scope naming patterns
• When to use which scope

Consistency Recommendations:

• Areas of good consistency
• Areas needing improvement
• Specific guidance for better consistency

5. Format Output

Text Format (default):

Git Commit Style Analysis
=========================

Commits Analyzed: 50
Branch: main
Conventional Commits: 87% (43/50)
Consistency Score: 85/100

Subject Lines:
  Average Length: 47 characters
  Recommended: Keep under 50 characters

Common Types:
  1. feat  - 35.4% (45 commits) - New features
  2. fix   - 29.9% (38 commits) - Bug fixes
  3. docs  - 15.7% (20 commits) - Documentation

Common Scopes:
  1. auth  - 18.1% (23 commits) - Authentication/authorization
  2. api   - 14.9% (19 commits) - API endpoints
  3. ui    - 11.8% (15 commits) - User interface

Patterns Detected:
  ✓ Uses imperative mood (92%)
  ✓ References issues frequently (67%)
  ○ Body usage moderate (34%)

Recommendations:
  • Continue using conventional commits format
  • Consider 'auth' scope for authentication changes
  • Keep subject lines under 50 characters
  • Use imperative mood (e.g., "add" not "added")
  • Reference issues when applicable (#123)

Sample Commits (project style):
  feat(auth): implement OAuth2 authentication
  fix(api): handle null pointer in user endpoint
  docs: update API documentation

JSON Format:

{
  "analysis_type": "commit_style",
  "commits_analyzed": 50,
  "branch": "main",
  "results": { ... },
  "recommendations": [ ... ],
  "confidence": "high"
}

Error Handling

No git repository:

• Error: "Not in a git repository. Run this command from within a git project."
• Exit code: 1

No commits:

• Error: "No commit history found. This appears to be a new repository."
• Exit code: 1

Branch doesn't exist:

• Error: "Branch 'branch-name' not found. Check branch name and try again."
• Exit code: 1

Insufficient commits:

• Warning: "Only X commits found. Analysis may be less accurate."
• Proceed with available commits

Git command fails:

• Error: "Git command failed: {error message}"
• Provide troubleshooting steps

Integration Usage

By commit-assistant agent:

User requests: "commit my changes"
  → Agent invokes: /history-analysis analyze-style
  → Learns: Project uses conventional commits, common scope: "auth"
  → Agent generates message matching project style

By message-generation skill:

Before generating message:
  → Invoke: /history-analysis analyze-style format:json
  → Extract: common_types, common_scopes, average_length
  → Use in: message generation to match project conventions

Output Examples

High Consistency Project (score: 95):

✓ Excellent consistency across commits
✓ Strong conventional commits adherence (98%)
✓ Clear scope usage patterns
→ Continue current practices

Medium Consistency Project (score: 65):

○ Moderate consistency
○ Mixed conventional commits usage (64%)
○ Inconsistent scope patterns
→ Recommend adopting conventional commits
→ Define standard scopes for the project

Low Consistency Project (score: 35):

✗ Low consistency across commits
✗ Minimal conventional commits usage (12%)
✗ No clear patterns
→ Consider establishing commit message guidelines
→ Define project-specific conventions
→ Use this tool to enforce standards

Success Criteria

Operation succeeds when:

• Git repository validated
• Commits successfully analyzed
• Statistics calculated accurately
• Patterns detected correctly
• Recommendations generated
• Output formatted properly
• Results match project reality

Performance

• Analysis Time: ~1-2 seconds for 50 commits
• Memory Usage: Minimal (processes line-by-line)
• Git Operations: Read-only, no modifications