Chapter 10. Test-Driven Development

Test-Driven Development (TDD) is a simple technique to produce high quality software. It is widely used in the Python community, but it is also very popular in other communities.

Testing is especially important in Python due to its dynamic nature. It lacks static typing so many, even minute, errors won't be noticed until the code is run and each of its line is executed. But the problem is not only how types in Python work. Remember that most bugs are not related to bad syntax usage, but rather to logical errors and subtle misunderstandings that can lead to major failures.

This chapter is split into two parts:

• I don't test, which advocates TDD and quickly describes how to do it with the standard library

• I do test, which is intended for developers who practice tests and wish to get more out of them