Analyze Test Coverage

Identify gaps in test coverage and suggest specs to write.

Arguments

• File path: Analyze coverage for specific file
• Directory: Analyze coverage for directory
• No argument: Analyze overall project coverage

Analysis Strategy

1. Check SimpleCov Setup

Look for SimpleCov in the project:

# spec/spec_helper.rb or spec/rails_helper.rb
require 'simplecov'
SimpleCov.start 'rails'

If not present, suggest adding it.

2. Run Coverage Report

COVERAGE=true bundle exec rspec
open coverage/index.html

3. Analyze Results

Parse coverage output to identify:

• Files with < 80% coverage
• Uncovered methods
• Uncovered branches
• Files with no specs at all

Coverage Analysis

For Specific File

1. Find corresponding spec file
2. Compare public methods in source vs described in spec
3. Identify missing test cases

For Directory

1. List all source files
2. Find missing spec files
3. Calculate coverage percentage

Project-Wide

1. List files without specs
2. Identify low-coverage areas
3. Prioritize by importance (models > services > helpers)

Output Format

Provide actionable report:

## Coverage Analysis

### Missing Specs (No spec file exists)
- app/services/notification_service.rb
- app/models/concerns/auditable.rb

### Low Coverage (< 80%)
- app/models/order.rb (65%)
  - Missing: #calculate_tax, #apply_discount
- app/services/payment_processor.rb (45%)
  - Missing: error handling paths

### Suggested Priority
1. OrderProcessor - critical business logic
2. PaymentProcessor - handles money
3. NotificationService - user-facing

Recommendations

When reporting coverage gaps:

• Prioritize critical business logic
• Suggest specific test cases
• Consider edge cases and error paths
• Note integration test opportunities

Examples

/rspec:coverage                      # Full project analysis
/rspec:coverage app/models/          # Models coverage
/rspec:coverage app/models/user.rb   # Single file coverage