Learn Python Testing & Best Practices: unittest, pytest, PEP8, Git, and Virtual Environments - Textnotes

Learn Python Testing & Best Practices: unittest, pytest, PEP8, Git, and Virtual Environments

Write reliable, maintainable Python code by learning unit testing, code formatting, version control with Git, and using virtual environments like venv and pipenv.

Objective:

Write high-quality Python code that is tested, consistent, version-controlled, and easy to maintain using testing frameworks, formatting standards, Git, and virtual environments.

Topics and Examples:

1. Unit Testing: unittest, pytest

Unit testing ensures your code works as expected.

Example (unittest):


import unittest

def add(a, b):
return a + b

class TestMath(unittest.TestCase):
def test_add(self):
self.assertEqual(add(2, 3), 5)
self.assertEqual(add(-1, 1), 0)

if __name__ == "__main__":
unittest.main()

Example (pytest):


# test_math.py
def add(a, b):
return a + b

def test_add():
assert add(2, 3) == 5
assert add(-1, 1) == 0

# Run: pytest test_math.py

2. Code Formatting: PEP8, Black

  1. PEP8: Python style guide for readable code
  2. Black: Automatic code formatter

Example (Black formatting):


# Original
def add( a,b ):
return a+b

# After Black
def add(a, b):
return a + b

3. Version Control with Git/GitHub

Version control helps track changes and collaborate on projects.

Basic Git Commands:


git init # Initialize repository
git add . # Stage changes
git commit -m "Message" # Commit changes
git branch # List branches
git checkout -b new_branch # Create and switch branch
git push origin main # Push changes to GitHub

4. Virtual Environments: venv, pipenv

Virtual environments isolate project dependencies to avoid conflicts.

Using venv:


# Create virtual environment
python -m venv myenv

# Activate environment (Windows)
myenv\Scripts\activate

# Activate environment (Linux/Mac)
source myenv/bin/activate

# Install packages
pip install requests

Using pipenv:


pip install pipenv
pipenv install requests # Install package in pipenv environment
pipenv shell # Activate pipenv shell

This section covers essential Python best practices, including unit testing with unittest/pytest, code formatting with PEP8 and Black, version control with Git/GitHub, and managing project dependencies using virtual environments like venv and pipenv.