Writing a simple unit test

Now that we took a quick look at all the type of tests that Magento offers, let's take a step back and look at unit tests again. In practice, unit tests are probably the ones that we will be writing most of the time. With this in mind, let's grab the Foggyline_Unitly module from https://github.com/ajzele/B05032-Foggyline_Unitly and start writing unit tests for it.

If you do not already have the Foggyline_Unitly module in the code base that was a part of the previous chapters, then you need to place its content under app/code/Foggyline/Unitly and execute the following commands on the console from the root of the Magento directory:

php bin/magento module:enable Foggyline_Unitly
php bin/magento setup:upgrade

The tests that we will write reside in the module's Test/Unit directory. This makes the entire path of the test directory look like app/code/Foggyline/Unitly/Test/Unit/. Magento knows that it needs to look inside this folder simply because of the...