Test case for operator "is" on reference types with result used as a boolean.

ICSharpCode.Decompiler/Ast/AstMethodBodyBuilder.cs

@@ -463,7 +463,7 @@ namespace ICSharpCode.Decompiler.Ast
 					case ILCode.Cge_Un:
 					case ILCode.Cge: return new Ast.BinaryOperatorExpression(arg1, BinaryOperatorType.GreaterThanOrEqual, arg2);
 					case ILCode.Clt_Un:
-					case ILCode.Clt: return new Ast.BinaryOperatorExpression(arg1, BinaryOperatorType.LessThan, arg2);
+					case ILCode.Clt:    return new Ast.BinaryOperatorExpression(arg1, BinaryOperatorType.LessThan, arg2);
 					#endregion
 					#region Logical
 					case ILCode.LogicNot:   return new Ast.UnaryOperatorExpression(UnaryOperatorType.Not, arg1);

ICSharpCode.Decompiler/Tests/TypeAnalysisTests.cs

@@ -114,4 +114,10 @@ public class TypeAnalysisTests
 			Console.WriteLine();
 		}
 	}
+
+	public void OperatorIs(object o)
+	{
+		Console.WriteLine(o is Random);
+		Console.WriteLine(!(o is Random));
+	}
 }