private void TestMove(OrderMovement orderMovement)
{
//Setup
var isContiguous = new List <IIsOrdered>();
for (int i = 0; i < 5; i++)
{
isContiguous.Add(new TestSubject {
Id = i, Order = i
});
}
var subject = isContiguous[2];
//Exercise
IsOrderedHelper.MoveWithinList(isContiguous, subject, orderMovement);
//Test and assert
Assert.IsTrue(IsOrderedHelper.IsContiguous(isContiguous));
if (orderMovement == OrderMovement.Up)
{
Assert.IsTrue(subject.Order == 1);
}
else
{
Assert.IsTrue(subject.Order == 3);
}
}
public static void MoveWithinList <T>(IEnumerable <T> list, T mover, OrderMovement orderMovement) where T : class, IIsOrdered
{
//Firm up enumeration problems
list = list.ToList();
//Ensure contiguousnes
MakeContiguous(list);
if (mover.Order == 0 && orderMovement == OrderMovement.Down)
{
return;//Nothing to do because this is already the first in the list
}
if (mover.Order == list.Count() && orderMovement == OrderMovement.Up)
{
return;//Nothing to do because this is already the last in the list
}
int delta;
switch (orderMovement)
{
case OrderMovement.Up:
delta = -1;
break;
case OrderMovement.Down:
delta = 1;
break;
default:
throw new System.NotImplementedException();
}
foreach (var iIsOrdered in list.OrderBy(i => i.Order))
{
if (iIsOrdered.Order == mover.Order + delta)
{
iIsOrdered.Order += -1 * delta;
mover.Order += delta;
break; //There is no need to continue
}
}
}
