A code smell is a symptom in the code that possibly indicates a deeper problem. It's where we look and think that there must be a better way of doing this. Tests also smell but they smell when they are run. There are different kinds of test smells and I will use the following method on these smells:
After reading this chapter, you will be able to identify test smells at an early stage and fight them in order to keep a good and healthy test suite.
One very common test smell when dealing with unit tests is that your tests break when you refactor, even though the functionality stays the same. These kinds of tests are called brittle tests.