From 5d7b054f14841b892fb04e27c431addd073959ce Mon Sep 17 00:00:00 2001
From: Phil Nash <phil@twobluecubes.com>
Date: Wed, 20 Apr 2011 19:09:41 +0100
Subject: [PATCH] Improved custom exception handling

---
 Test/ExceptionTests.cpp               | 34 ++++++++++-----
 catch.hpp                             |  1 +
 internal/catch_capture.hpp            |  4 +-
 internal/catch_interfaces_exception.h | 63 +++++++++++++++++++--------
 4 files changed, 71 insertions(+), 31 deletions(-)

diff --git a/Test/ExceptionTests.cpp b/Test/ExceptionTests.cpp
index caad6fd8..1d45200e 100644
--- a/Test/ExceptionTests.cpp
+++ b/Test/ExceptionTests.cpp
@@ -79,19 +79,33 @@ private:
     std::string m_msg;
 };
 
-
-namespace Catch
+CATCH_TRANSLATE_EXCEPTION( CustomException& ex )
 {
-    ExceptionTranslator<CustomException> translator;
-
-    template<>
-    std::string ExceptionTranslator<CustomException>::translate( CustomException& ex ) const
-    {
-        return ex.getMessage();
-    }
+    return ex.getMessage();
 }
 
-TEST_CASE_NORETURN( "./succeeding/exceptions/custom", "" )
+CATCH_TRANSLATE_EXCEPTION( double& ex )
+{
+    return Catch::toString( ex );
+}
+
+TEST_CASE_NORETURN( "./failing/exceptions/custom", "Unexpected custom exceptions can be translated" )
 {
     throw CustomException( "custom exception" );
 }
+
+TEST_CASE( "./failing/exceptions/custom/nothrow", "Custom exceptions can be translated when testing for nothrow" )
+{
+    REQUIRE_NOTHROW( throw CustomException( "unexpected custom exception" ) );
+}
+
+TEST_CASE( "./failing/exceptions/custom/throw", "Custom exceptions can be translated when testing for throwing as something else" )
+{
+    REQUIRE_THROWS_AS( throw CustomException( "custom exception - not std" ), std::exception );
+}
+
+
+TEST_CASE_NORETURN( "./failing/exceptions/custom/double", "Unexpected custom exceptions can be translated"  )
+{
+    throw double( 3.14 );
+}
diff --git a/catch.hpp b/catch.hpp
index 488dde45..f9ff324c 100644
--- a/catch.hpp
+++ b/catch.hpp
@@ -60,6 +60,7 @@
 #define METHOD_AS_TEST_CASE( method, name, description ) CATCH_METHOD_AS_TEST_CASE( method, name, description )
 
 #define REGISTER_REPORTER( name, reporterType ) INTERNAL_CATCH_REGISTER_REPORTER( name, reporterType )
+#define CATCH_TRANSLATE_EXCEPTION( signature ) INTERNAL_CATCH_TRANSLATE_EXCEPTION( signature )
 
 #define GENERATE( expr) INTERNAL_CATCH_GENERATE( expr )
 
diff --git a/internal/catch_capture.hpp b/internal/catch_capture.hpp
index 6763353a..55980469 100644
--- a/internal/catch_capture.hpp
+++ b/internal/catch_capture.hpp
@@ -735,7 +735,7 @@ inline bool isTrue
     } \
     catch( ... ) \
     { \
-        INTERNAL_CATCH_ACCEPT_EXPR( Catch::ResultBuilder( __FILE__, __LINE__, macroName, #expr ).setResultType( Catch::ResultWas::ThrewException ), stopOnFailure ); \
+        INTERNAL_CATCH_ACCEPT_EXPR( ( Catch::ResultBuilder( __FILE__, __LINE__, macroName, #expr ) << Catch::Hub::getExceptionTranslatorRegistry().translateActiveException() ).setResultType( Catch::ResultWas::ThrewException ), stopOnFailure ); \
     }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -759,7 +759,7 @@ inline bool isTrue
     INTERNAL_CATCH_THROWS( expr, exceptionType, stopOnFailure, macroName ) \
     catch( ... ) \
     { \
-        INTERNAL_CATCH_ACCEPT_EXPR( Catch::ResultBuilder( __FILE__, __LINE__, macroName, #expr ).setResultType( Catch::ResultWas::ThrewException ), stopOnFailure ); \
+        INTERNAL_CATCH_ACCEPT_EXPR( ( Catch::ResultBuilder( __FILE__, __LINE__, macroName, #expr ) << Catch::Hub::getExceptionTranslatorRegistry().translateActiveException() ).setResultType( Catch::ResultWas::ThrewException ), stopOnFailure ); \
     }
 
 ///////////////////////////////////////////////////////////////////////////////
diff --git a/internal/catch_interfaces_exception.h b/internal/catch_interfaces_exception.h
index b7edc013..0e17fa36 100644
--- a/internal/catch_interfaces_exception.h
+++ b/internal/catch_interfaces_exception.h
@@ -38,30 +38,55 @@ namespace Catch
         
     };
 
-    template<typename T>
-    class ExceptionTranslator : public IExceptionTranslator
+    class ExceptionTranslatorRegistrar
     {
+        template<typename T>
+        class ExceptionTranslator : public IExceptionTranslator
+        {
+        public:
+            
+            ExceptionTranslator
+            (
+                std::string(*translateFunction)( T& ) 
+            )
+            : m_translateFunction( translateFunction )
+            {}
+            
+            virtual std::string translate
+            ()
+            const
+            {
+                try
+                {
+                    throw;
+                }
+                catch( T& ex )
+                {
+                    return m_translateFunction( ex );
+                }
+            }
+            
+        protected:
+            std::string(*m_translateFunction)( T& );
+        };
+        
     public:
-        ExceptionTranslator()
+        template<typename T>
+        ExceptionTranslatorRegistrar
+        (
+            std::string(*translateFunction)( T& ) 
+        )
         {
-            Catch::Hub::getExceptionTranslatorRegistry().registerTranslator( this );
+            Catch::Hub::getExceptionTranslatorRegistry().registerTranslator
+                ( new ExceptionTranslator<T>( translateFunction ) );
         }
-        
-        virtual std::string translate() const
-        {
-            try
-            {
-                throw;
-            }
-            catch( T& ex )
-            {
-                return translate( ex );
-            }
-        }
-        
-    protected:
-        std::string translate( T& ex ) const;
     };
 }
 
+///////////////////////////////////////////////////////////////////////////////
+#define INTERNAL_CATCH_TRANSLATE_EXCEPTION( signature ) \
+    static std::string INTERNAL_CATCH_UNIQUE_NAME( catch_internal_ExceptionTranslator )( signature ); \
+    namespace{ Catch::ExceptionTranslatorRegistrar INTERNAL_CATCH_UNIQUE_NAME( catch_internal_ExceptionRegistrar )( &INTERNAL_CATCH_UNIQUE_NAME( catch_internal_ExceptionTranslator ) ); }\
+    static std::string INTERNAL_CATCH_UNIQUE_NAME(  catch_internal_ExceptionTranslator )( signature )
+
 #endif // TWOBLUECUBES_CATCH_INTERFACES_EXCEPTIONS_H_INCLUDED