void WithUninitializedIntegerData_ShouldNotBeValid()
{
var data = new IntegerData();
data.IsValid().Should().BeFalse();
}
void WithNullIntegerData_ShouldNotBeValid()
{
IntegerData data = (long?)null;
data.IsValid().Should().BeFalse();
}
void WithValidIntegerData_ShouldBeValid()
{
var data = new IntegerData(42);
data.IsValid().Should().BeTrue();
}