TestSetterAndGetterTrait: Impossible to set expected value if it evaluates to 'true'

[TiSiE]

Whenever you define an expected value via the 'expect(_*)' or 'setter_value(_*)' specifications which evaluates to true [1], it is ignored and the 'value(_*)' specification is used instead

---

[1]: such as a non-empty string, the boolean true, a non-zero number, a non-empty array and so on...