Python Crash Course

11TESTING YOUR CODE

When you write a function or a class, you can also write tests for that code. Testing proves that your code works as it’s supposed to in response to all the input types it’s designed to receive. When you write tests, you can be confident that your code will work correctly as more people begin to use your programs. You’ll also be able to test new code as you add it to make sure your changes don’t break your program’s existing behavior. Every programmer makes mistakes, so every programmer must test their code often, catching problems before users encounter them.

In this chapter you’ll learn to test your code using tools in Python’s ...