Introduction to unit testing

With unit testing, you break up code into small pieces, called units, that can be tested independently from each other. These units can consist of classes, methods, or single lines of code. The smaller the better works best here. This will give you a better view of how your code is performing and allows tests to be run fast.

In most cases, unit tests are written by the developer that writes the code. There are two different ways of writing unit tests: before you write the actual production code, or after. Most programmers write it afterwards, which is the traditional way of doing things, but if you are using test-driven development (TDD), you will typically write them beforehand. Unit testing will also make code documentation easier. It encourages better coding practices and you can leave code pieces to describe the code's functionality behind. Here, you will focus more on updating a system of checks.

In the next section, we are going to cover...