# Test Suite Summary for yt_info_extract

## Overview

Comprehensive test suite with **94% code coverage** including unit tests and end-to-end tests.

## Test Structure

### Unit Tests (109 tests)
- **test_extractor.py** - Core extractor functionality (25 tests)
- **test_utils.py** - Utility functions (25 tests)  
- **test_cli.py** - CLI functionality (24 tests)
- **test_init.py** - Convenience functions (23 tests)
- **test_coverage_gaps.py** - Edge cases (12 tests)

### End-to-End Tests (27 tests)
- **test_e2e.py** - Real network calls to YouTube

## Coverage Report

| Module | Coverage | Status |
|--------|----------|---------|
| `__init__.py` | 100% | ✅ Complete |
| `utils.py` | 100% | ✅ Complete |
| `cli.py` | 96% | ✅ Excellent |
| `extractor.py` | 88% | ✅ Good |
| **Overall** | **94%** | ✅ Production Ready |

## Running Tests

### Quick Commands

```bash
# Run all unit tests
pytest tests/ -v

# Run unit tests with coverage
pytest --cov=yt_info_extract --cov-report=term-missing tests/

# Run only E2E tests (requires internet)
pytest tests/test_e2e.py -m e2e

# Quick smoke test
./run_e2e_tests.sh 5
```

### E2E Test Options

```bash
./run_e2e_tests.sh [option]

Options:
  1 - All E2E tests (slow, ~2-3 minutes)
  2 - API strategy tests only  
  3 - yt-dlp strategy tests only
  4 - CLI tests only
  5 - Quick smoke test (default, ~10 seconds)
```

## Test Categories

### Unit Tests
- ✅ **URL Parsing** - Various YouTube URL formats
- ✅ **Error Handling** - Invalid inputs, network errors
- ✅ **Mock API Calls** - Simulated YouTube API responses
- ✅ **Strategy Selection** - Auto, API, yt-dlp, pytubefix
- ✅ **Batch Processing** - Multiple video extraction
- ✅ **Export Functions** - JSON, CSV output
- ✅ **CLI Arguments** - All command-line options
- ✅ **Rate Limiting** - Request delays and retries

### E2E Tests  
- ✅ **Real API Calls** - YouTube Data API v3
- ✅ **yt-dlp Integration** - Actual video extraction
- ✅ **pytubefix Integration** - Fallback extraction
- ✅ **Performance Tests** - Batch processing timing
- ✅ **Network Resilience** - Retry mechanisms
- ✅ **CLI Integration** - End-to-end command testing

## Test Videos Used

E2E tests use stable, well-known videos:
- **jNQXAC9IVRw** - "Me at the zoo" (first YouTube video)
- **dQw4w9WgXcQ** - Rick Astley - Never Gonna Give You Up
- **9bZkp7q19f0** - PSY - GANGNAM STYLE

## Requirements for Testing

### Unit Tests
- pytest
- pytest-cov
- No internet required

### E2E Tests  
- Internet connection
- Optional: YOUTUBE_API_KEY environment variable
- yt-dlp and/or pytubefix installed

## Continuous Integration

Tests are structured to support CI/CD:

```yaml
# Example GitHub Actions workflow
- name: Run Unit Tests
  run: pytest tests/ --cov=yt_info_extract
  
- name: Run E2E Smoke Tests
  run: ./run_e2e_tests.sh 5
  env:
    YOUTUBE_API_KEY: ${{ secrets.YOUTUBE_API_KEY }}
```

## Test Maintenance

- Unit tests are stable and don't require maintenance
- E2E tests may need updates if YouTube changes
- Test videos chosen for long-term stability
- Mock data isolated from implementation details

## Coverage Gaps (6%)

Remaining uncovered code consists of:
- Import error handling for optional dependencies
- Specific HTTP error response handling
- Some logging statements
- Edge cases in error recovery

These are acceptable gaps that don't affect functionality.