public void SelectsInverse()
{
var spec = new IntegerGreaterThanZero();
var negatedSpec = new Negation<int>(spec);
Assert.That(negatedSpec.IsSatisfiedBy(1), Is.False);
Assert.That(negatedSpec.IsSatisfiedBy(0), Is.True);
Assert.That(negatedSpec.IsSatisfiedBy(-1), Is.True);
}