@Test
public void callingTheBinderYieldsPredicateResult() {
final Box<Boolean> result = Box.empty();
final Predicate<O> spy = Spies.spyRes(new Always<O>(), result);
final Proposition proposition = new PredicateBinder<O>(spy, O.ONE);
proposition.state();
Assert.assertEquals(Boolean.TRUE, result.getContent());
}