From 0130dfac4139989c4860a7159573c03ed345d11a Mon Sep 17 00:00:00 2001
From: Phil Nash <phil@twobluecubes.com>
Date: Wed, 9 Mar 2011 09:32:03 +0000
Subject: [PATCH] First attempt at solving signed/ unsigned issue with int
 literals

---
 internal/catch_unsigned.hpp | 105 ++++++++++++++++++++++++++++++++++++
 1 file changed, 105 insertions(+)
 create mode 100644 internal/catch_unsigned.hpp

diff --git a/internal/catch_unsigned.hpp b/internal/catch_unsigned.hpp
new file mode 100644
index 00000000..38989bef
--- /dev/null
+++ b/internal/catch_unsigned.hpp
@@ -0,0 +1,105 @@
+/*
+ *  catch_unsigned.hpp
+ *  Catch
+ *
+ *  Created by Phil on 04/03/2011.
+ *  Copyright 2011 Two Blue Cubes Ltd. All rights reserved.
+ *
+ *  Distributed under the Boost Software License, Version 1.0. (See accompanying
+ *  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+ *
+ */
+
+#ifndef TWOBLUECUBES_CATCH_UNSIGNED_HPP_INCLUDED
+#define TWOBLUECUBES_CATCH_UNSIGNED_HPP_INCLUDED
+
+#include <limits>
+
+namespace Catch
+{
+    template<typename T>
+    struct SignTraits{};
+    
+    template<>
+    struct SignTraits<int>
+    {
+        typedef int SignedType;
+        typedef unsigned int UnsignedType;
+    };
+    template<>
+    struct SignTraits<unsigned int> : SignTraits<int>{};
+    
+    template<>
+    struct SignTraits<long>
+    {
+        typedef long SignedType;
+        typedef unsigned long UnsignedType;
+    };
+    template<>
+    struct SignTraits<unsigned long> : SignTraits<long>{};
+    
+    template<>
+    struct SignTraits<char>
+    {
+        typedef char SignedType;
+        typedef unsigned char UnsignedType;
+    };
+    template<>
+    struct SignTraits<unsigned char> : SignTraits<char>{};
+    
+    template<typename ActualT, typename TestT>
+    struct IsType
+    {
+        enum{ result = false };
+    };
+    
+    template<typename T>
+    struct IsType<T, T>
+    {
+        enum{ result = true };
+    };
+    
+    template<typename T1, typename T2, bool>
+    struct MatchedSigns
+    {
+        static const T1& castLhs( const T1& lhs )
+        {
+            return lhs;
+        }
+        static const T2& castRhs( const T2& rhs )
+        {
+            return rhs;
+        }
+    };
+    
+    template<typename T1, typename T2>
+    struct MatchedSigns<T1, T2, false>
+    {
+        typedef typename SignTraits<T1>::SignedType Type1;
+        typedef typename SignTraits<T2>::SignedType Type2;
+        
+        static Type1 castLhs( T1 lhs )
+        {
+            return static_cast<Type1>( lhs );
+        }
+        static Type2 castRhs( T2 rhs )
+        {
+            return static_cast<Type2>( rhs );
+        }
+    };
+    
+    template<typename T1, typename T2>
+    struct MatchSign 
+        : MatchedSigns< T1, T2, 
+            (   !IsType<T1, int>::result && 
+                !IsType<T1, long>::result && 
+                !IsType<T2, int>::result && 
+                !IsType<T2, long>::result ) ||
+                !std::numeric_limits<T1>::is_integer || 
+                !std::numeric_limits<T2>::is_integer ||
+                std::numeric_limits<T1>::is_signed == std::numeric_limits<T2>::is_signed >
+    {
+    };
+}
+
+#endif // TWOBLUECUBES_CATCH_UNSIGNED_HPP_INCLUDED