Imported Upstream version 3.6.0

Former-commit-id: da6be194a6b1221998fc28233f2503bd61dd9d14

mcs/tests/test-315.cs

@@ -0,0 +1,44 @@
+using System;
+
+public interface IDirectedEnumerable
+{
+	IDirectedEnumerable Backwards();
+}
+
+public interface IDirectedCollectionValue : IDirectedEnumerable
+{
+	new IDirectedCollectionValue Backwards();
+}
+
+public class GuardedCollectionValue : IDirectedCollectionValue
+{
+	IDirectedEnumerable IDirectedEnumerable.Backwards ()
+	{
+		return this;
+	}
+
+	public IDirectedCollectionValue Backwards ()
+	{
+		return this;
+	}
+}
+
+public interface ISequenced : IDirectedCollectionValue
+{
+}
+
+public class GuardedSequenced
+{
+	ISequenced sequenced;
+
+	public IDirectedCollectionValue Test ()
+	{
+		return sequenced.Backwards();
+	}
+}
+
+class X
+{
+	public static void Main ()
+	{ }
+}