Programming Ruby 3.3

Why Unit Test?

It’s important to be able to test individual units for many reasons, one of which is that being able to isolate code into testable units is useful for ongoing changes and maintenance. Code in one unit often relies on the correct operation of the code in other units. If one unit turns out to contain bugs, then all the code that depends on that unit is potentially affected. This is a big problem.

When you unit test this code as you write it, two things can happen. First, you’re more likely to find the bug while the code was still fresh in your mind. Second, because the unit test was only interacting with the code you just wrote, when a bug does appear, you only have to look through a handful of lines of code to find it, rather than ...