“Is” returns more than a Boolean

The name of a method is a predicate suggesting a true/false value in return. However the return type is not Boolean but rather a more complex type thus allowing a wider range of values without documenting them.

Example: isValid with return type int.

Related smells: Not answered question

Reference

Venera Arnaoudova, Massimiliano Di Penta, Giuliano Antoniol. “Linguistic antipatterns: what they are and how developers perceive them". in Empirical Software Engineering (ESEM), 21(1), Feb 2016. 104-158. 10.1007/s10664-014-9350-8