Description

Testing helps ensure that your app will work as expected for your end users.

Software projects with high test coverage are never perfect, but it's a good initial indicator of the quality of the software. Additionally, testable code is generally a sign of a good software architecture, which is why advanced developers take testing into account throughout the entire development lifecycle.

Types of tests:

1. Unit
2. Integration/Functional
3. End-to-end

Unit tests test the functionality of an individual unit of code isolated from its dependencies. They are the first line of defense against errors and inconsistencies in your codebase. Unit testing is a fundamental part of the Test-Driven Development (TDD) process.

Unit testing improves the maintainability of your code.

Maintainability refers to making bug fixes or enhancements to your code or to another developer needing to update your code at some point in the future.

Unit testing should be combined with a Continuous Integration (CI) process to ensure that your unit tests are constantly executing, ideally on each commit to your repository. A solid suite of unit tests can be critical to catching defects quickly and early in the development process before your end users come across them in production.

The testing-related articles and tutorials on TestDriven.io teach how to use pytest for unit and integration tests and Cypress for end-to-end tests. You'll learn best practices and techniques to follow when testing your Python applications as well.