Code smell is a technical debt or symptom that indicates a deeper problem. Smells are not bugs, or they don't fail tests. Instead, they indicate a problem in design or code such that a rigid code cannot be enhanced or can create a maintenance issue. This section covers the test smells that should be refactored for maintenance and readability. The following topics are covered:
Test code duplication
Conditions in test code
Test logic in the production code
Over engineering
Code duplication is the simplest code smell. It creates maintainability problems. The same code is written in many places; if any bug is found, then you need to modify all other places. This subsection elaborates on the duplicate code in test cases.
Suppose you are designing a hospital management system and writing a test for checking a patient in. The following objects are needed for the patient check-in process: a person, a guarantor, reason for hospitalization, the attending physician...