/// <summary>
/// </summary>
public static Tuple Calculate(IPythonType startingType, Tuple bases, bool forceNewStyle)
{
if (bases.ContainsValue(startingType)) {
throw Ops.TypeError("a __bases__ item causes an inheritance cycle");
}
List<IPythonType> mro = new List<IPythonType>();
mro.Add(startingType);
if (bases.Count != 0) {
List<List<IPythonType>> mroList = new List<List<IPythonType>>();
// build up the list - it contains the MRO of all our
// bases as well as the bases themselves in the order in
// which they appear.
int oldSytleCount = 0;
foreach (IPythonType type in bases) {
if (!(type is DynamicType))
oldSytleCount++;
}
foreach (IPythonType type in bases) {
DynamicType dt = type as DynamicType;
if (dt != null) {
mroList.Add(TupleToList(dt.MethodResolutionOrder));
} else if (oldSytleCount == 1 && !forceNewStyle) {
mroList.Add(GetOldStyleMro(type));
} else {
mroList.Add(GetNewStyleMro(type));
}
}
mroList.Add(TupleToList(bases));
int lastRemove = -1;
for (; ; ) {
bool removed = false, sawNonZero = false;
// now that we have our list, look for good heads
for (int i = 0; i < mroList.Count; i++) {
if (mroList[i].Count == 0) continue; // we've removed everything from this list.
sawNonZero = true;
IPythonType head = mroList[i][0];
// see if we're in the tail of any other lists...
bool inTail = false;
for (int j = 0; j < mroList.Count; j++) {
if (mroList[j].Count != 0 && !mroList[j][0].Equals(head) && mroList[j].Contains(head)) {
inTail = true;
break;
}
}
if (!inTail) {
lastRemove = i;
if (mro.Contains(head)) {
throw Ops.TypeError("a __bases__ item causes an inheritance cycle");
}
// add it to the linearization, and remove
// it from our lists
mro.Add(head);
for (int j = 0; j < mroList.Count; j++) {
mroList[j].Remove(head);
}
removed = true;
break;
}
}
if (!sawNonZero) break;
if (!removed) {
// we've iterated through the list once w/o removing anything
throw Ops.TypeError("invalid order for base classes: {0} {1}",
mroList[0][0],
mroList[1][0]);
}
}
}
return new Tuple(mro);
}
