Software Architect's Handbook

Easy to set up and implement

Unit tests should be easy to set up and implement. If they are not, this is a code smell, which is a symptom in the system that may indicate a larger problem. The problem could be in the way that the unit being tested is designed or in the way that the test is being written.

Although we want a high amount of unit test coverage, we do not want developers to spend inordinate amounts of time writing a single unit test. Unit tests should be easy to write.