private static TypeInheritance GetInheritanceTree(this Type type, int distance)
{
var list = new TypeInheritance(type, distance);
// Gives us a map of Interface + All ancestor interfaces in the entire hierarchy up.
var interfaces = type
.GetInterfaces()
.Select(i => new { Interface = i, Ancestors = i.GetInterfaces().Traverse(TraverseKind.BreadthFirst, n => n.GetInterfaces()) });
if (type.IsClass)
{
if (type.BaseType != null)
list.Inheritance.Add(GetInheritanceTree(type.BaseType, distance + 1));
list.Inheritance.AddRange(type
// Add all interfaces of the type, but
.GetInterfaces()
// See if the map gives us where the interface members are implemented
.Select(i => new { Interface = i, Map = type.GetInterfaceMap(i) })
// Either it is a marker interface, or all members are declared by the type.
// (explicit interface implementation or otherwise we are the first class in the hierarchy to introduce the interface).
.Where(i =>
// Detect marker interfaces separately, and add them always as long as they don't show up in others upward.
(!i.Map.TargetMethods.Any() && !interfaces.SelectMany(n => n.Ancestors).Any(t => t == i.Interface)) ||
// For interfaces with members, we can get the map and check if they are declared in the current type.
// Note that this brings into this type the interfaces that have a completely overriden implementation (our intended design).
(i.Map.TargetMethods.Any() && i.Map.TargetMethods.All(m => m.DeclaringType == type)))
.Select(i => GetInheritanceTree(i.Interface, distance + 1)));
}
else
{
// Then we only add those interfaces that do not show up as ancestors in any other
// interface in the list.
list.Inheritance.AddRange(interfaces
.Select(i => i.Interface)
.Where(i => !interfaces.SelectMany(n => n.Ancestors).Any(t => t == i))
.Select(i => GetInheritanceTree(i, distance + 1)));
}
return list;
}
private static void PrintTypeList(TypeInheritance list, int indentLevel)
{
Console.WriteLine(
Enumerable.Range(0, indentLevel).Aggregate("", (s, level) => s += '\t') +
list.Type.Name + " (" + list.Distance + ")");
indentLevel++;
foreach (var inner in list.Inheritance)
{
PrintTypeList(inner, indentLevel);
}
}
