First cut of new AssertionHandler/ Decomposer

- integrated into INTERNAL_CATCH_TEST. Needs more work to fully replace existing stuff

include/internal/catch_assertionhandler.h

@@ -0,0 +1,61 @@
+/*
+ *  Created by Phil on 8/8/2017.
+ *  Copyright 2017 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_ASSERTIONHANDLER_H_INCLUDED
+#define TWOBLUECUBES_CATCH_ASSERTIONHANDLER_H_INCLUDED
+
+#include "catch_decomposer.h"
+#include "catch_assertioninfo.h"
+
+namespace Catch {
+
+    struct TestFailureException{};
+
+    class LazyExpression {
+        friend class AssertionHandler;
+        friend struct AssertionStats;
+
+        ITransientExpression const* m_transientExpression = nullptr;
+        bool m_isNegated;
+    public:
+        LazyExpression( bool isNegated );
+        LazyExpression( LazyExpression const& other );
+        LazyExpression& operator = ( LazyExpression const& ) = delete;
+
+        explicit operator bool() const;
+
+        friend auto operator << ( std::ostream& os, LazyExpression const& lazyExpr ) -> std::ostream&;
+    };
+
+    class AssertionHandler {
+        AssertionInfo m_assertionInfo;
+        bool m_shouldDebugBreak = false;
+        bool m_shouldThrow = false;
+    public:
+        AssertionHandler
+            (   StringRef macroName,
+                SourceLineInfo const& lineInfo,
+                StringRef capturedExpression,
+                ResultDisposition::Flags resultDisposition );
+
+        void handle( ITransientExpression const& expr );
+
+        template<typename T>
+        void handle( ExprLhs<T> const& expr ) {
+            handle( expr.makeUnaryExpr() );
+        }
+
+        auto shouldDebugBreak() const -> bool;
+        void reactWithDebugBreak() const;
+        void reactWithoutDebugBreak() const;
+        void useActiveException( ResultDisposition::Flags resultDisposition );
+        void useActiveException();
+    };
+
+} // namespace Catch
+
+#endif // TWOBLUECUBES_CATCH_ASSERTIONHANDLER_H_INCLUDED