Python Testing with Pytest

ETPS Test Structure

• Tests live in backend/tests/test_*.py
• Use pytest with pytest-asyncio for async code
• Mock LLM: from services.llm.mock_llm import MockLLM
• Current test count: 700+ passing

Test Pattern

import pytest
from services.llm.mock_llm import MockLLM

@pytest.mark.asyncio
async def test_my_function():
    mock_llm = MockLLM()
    result = await some_async_function(llm=mock_llm)
    assert result == expected

Running Tests

cd backend
python -m pytest -v                    # All tests
python -m pytest tests/test_file.py -v # Specific file
python -m pytest --tb=long             # Full tracebacks
python -m pytest -k "keyword"          # Filter by name

Key Test Files

• test_pagination_allocation.py - Pagination service
• test_bullet_rewriter.py - Bullet operations
• test_critic.py - Quality evaluation
• test_skill_gap.py - Skill analysis
• test_text_output.py - Resume/cover letter text output
• test_security.py - Security tests

Mocking Patterns

# Mock LLM
from services.llm.mock_llm import MockLLM
mock_llm = MockLLM()

# Mock database session
from unittest.mock import MagicMock
mock_db = MagicMock()

Best Practices

1. All tests must pass before commits
2. Use fixtures for shared setup
3. Mock external services (LLM, vector store, APIs)
4. Test async code with @pytest.mark.asyncio
5. Use descriptive assertion messages
6. Test edge cases and error conditions