mcs/tests/gtest-294.cs

   1 class A {}
   2 class B : A {}
   3
   4 class X
   5 {
   6         public static A Test (A a, B b)
   7         {
   8                 return b ?? a;
   9         }
  10
  11         static int Main ()
  12         {
  13                 A a = new A ();
  14                 B b = new B ();
  15
  16                 if (Test (a, b) != b)
  17                         return 1;
  18
  19                 if (Test (null, b) != b)
  20                         return 2;
  21
  22                 if (Test (a, null) != a)
  23                         return 3;
  24
  25                 if (Test (null, null) != null)
  26                         return 4;
  27
  28                 return 0;
  29
  30         }
  31 }