Python testing best practices using pytest including fixtures, parametrization, mocking, coverage analysis, async testing, and test organization. Use when writing or improving Python tests.
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What the file says
# Python Testing
> This skill provides comprehensive Python testing patterns using pytest as the primary testing framework.
## Testing Framework
Use **pytest** as the testing framework for its powerful features and clean syntax.
### Basic Test Structure
```python
def test_user_creation():
"""Test that a user can be created with valid data"""
user = User(name="Alice", email="alice@example.com")
assert user.name == "Alice"
assert user.email == "alice@example.com"
assert user.is_active is True
```
### Test Discovery
pytest automatically discovers tests following these conventions:
- Files: `test_*.py` or `*_test.py`
- Functions: `test_*`
- Classes: `Test*` (without `__init__`)
- Methods: `test_*`
## Fixtures
Fixtures provide reusable test setup and teardown:
```python
import pytest
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
@pytest.fixture
def db_session():
"""Provide a database session for tests"""
engine = create_engine("sqlite:///:memory:")
Session = sessionmaker(bind=engine)
session = Session()
# Setup
Base.metadata.create_all(engine)
yield session
# Teardown
session.close()
…
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Source
GitHub
affaan-m/ecc · 299,696 stars · license MIT · pushed 2026-11-06 · branch main
API
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