public void MatchesSingleSelectionCost()
{
DistinctBookSelection selection = new DistinctBookSelection(1, 2, 3);
decimal expectedCost = selection.CalculateCost();
BookSelectionGroup group = new BookSelectionGroup(selection);
Assert.Equal(expectedCost, group.CalculateTotalCost());
}
public void TallySelectionCosts()
{
var selection = new[]
{
new DistinctBookSelection(1, 2),
new DistinctBookSelection(2, 3),
new DistinctBookSelection(3, 4)
};
decimal expectedCost = selection.Sum(selection => selection.CalculateCost());
BookSelectionGroup group = new BookSelectionGroup(selection);
Assert.Equal(expectedCost, group.CalculateTotalCost());
}
public void Returns0GivenNoSelections()
{
BookSelectionGroup group = new BookSelectionGroup();
Assert.Equal(0m, group.CalculateTotalCost());
}