Testing

Case Study: Building Software in Python

Mark Pedigo

Principal Data Scientist

Roadmap

Roadmap showcasing what parts of the project we've finished and which we'll be starting.

Why automated testing?

Automatic, software-driven testing
No human intervention required
Simple checks to comprehensive assessments

A robot testing code

Benefits of automated testing

Improved code quality
Risk mitigation
Enhanced user experience

What Do Unit Tests Do?

Individual components or functions tested individually
Focus on the smallest parts of an application
Verify expected output given input

A magnifying glass examining blocks

What is the pytest library?

Popular testing framework for Python
Supports unit testing
Known for simplicity, flexibility, and features

Advantages of pytest

Simplicity and readability
Powerful fixtures
Integrates with other tools

Unit test - example

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

# test_math.py
import pytest
def test_add():
    assert add(2, 3) == 5
    assert add(-1, 1) == 0
    assert add(0, 0) == 0
    assert add(-5, -7) == -12

Run in the console:

pytest test_math.py

===== test session starts =====
collected 1 item
test_math_functions.py .                                                   [100%]
====== 1 passed in 0.03s ======

Let's practice!

Case Study: Building Software in Python