Add nested_inheritance_interface test for csharp

Examples/test-suite/csharp/nested_inheritance_interface_runme.cs

@@ -0,0 +1,32 @@
+using System;
+using System.Collections.Generic;
+using nested_inheritance_interfaceNamespace;
+
+public class nested_inheritance_interface_runme {
+
+  static string SortArrayToString(string[] types) {
+    Array.Sort<string>(types);
+    return string.Join(" ", types);
+  }
+
+  static string SortArrayToString(Type[] types) {
+    List<string> stypes = new List<string>();
+    foreach (Type t in types)
+      stypes.Add(t.Name);
+    return SortArrayToString(stypes.ToArray());
+  }
+
+  public static void Main() {
+    Type[] BNInterfaces = typeof(B.N).GetInterfaces();
+    string expectedInterfacesString = "IASwigInterface IDisposable";
+    string actualInterfacesString = SortArrayToString(BNInterfaces);
+    if (expectedInterfacesString != actualInterfacesString)
+      throw new Exception("Expected interfaces for " + typeof(B.N).Name + ": \n" + expectedInterfacesString + "\n" + "Actual interfaces: \n" + actualInterfacesString);
+
+    if (!typeof(IASwigInterface).IsInterface)
+      throw new Exception(typeof(IASwigInterface).Name + " should be an interface but is not");
+
+    // overloaded methods check
+    B.N d = new B.N();
+  }
+}