Missing Default

This smell occurs when a switch statement does not contain a default case.

Reference

Tushar Sharma, Marios Fragkoulis, and Diomidis Spinellis. “House of Cards: Code Smells in Open-Source C# Repositories". in ACM/IEEE International Symposium on Empirical Software Engineering and Measurement (ESEM). 424-429. 10.1109/ESEM.2017.57.