public void should_not_charge_given_reading_amount_not_changed()
{
var subject = new LifelineSite();
subject.AddReading(new Reading(10, new DateTime(1997, 1, 1)));
subject.AddReading(new Reading(10, new DateTime(1997, 2, 1)));
Assert.Equal(new Dollars(0), subject.Charge());
}
public void should_charge_4_91_given_reading_amount_increase_101()
{
var subject = new LifelineSite();
subject.AddReading(new Reading(1000, new DateTime(1997, 1, 1)));
subject.AddReading(new Reading(1101, new DateTime(1997, 2, 1)));
Assert.Equal(new Dollars(4.91), subject.Charge());
}
public void should_charge_given_reading_amount_max_increaseds()
{
var subject = new LifelineSite();
subject.AddReading(new Reading(0, new DateTime(1997, 1, 1)));
subject.AddReading(new Reading(int.MaxValue, new DateTime(1997, 2, 1)));
Assert.Equal(new Dollars(1.9730005337E8), subject.Charge());
}
public void should_charge_11_77_given_reading_amount_increase_201()
{
var subject = new LifelineSite();
subject.AddReading(new Reading(50, new DateTime(1997, 1, 1)));
subject.AddReading(new Reading(251, new DateTime(1997, 2, 1)));
Assert.Equal(new Dollars(11.77), subject.Charge());
}
public void should_throw_exception_given_no_reading()
{
var subject = new LifelineSite();
Assert.Throws<NullReferenceException>(() => subject.Charge());
}