From 218d0bdcc75cccc0871fdc0c46a229a88d39f034 Mon Sep 17 00:00:00 2001
From: Eirik Byrkjeflot Anonsen <eirik@eirikba.org>
Date: Mon, 4 Apr 2016 18:51:33 +0200
Subject: [PATCH] Eliminate dynamic cast by promoting interface to parent class

This eliminates one use of RTTI in Catch.
---
 include/internal/catch_interfaces_reporter.h |  7 +++++++
 include/reporters/catch_reporter_multi.hpp   | 16 +++++++++++-----
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/include/internal/catch_interfaces_reporter.h b/include/internal/catch_interfaces_reporter.h
index d1c6e704..26d20e24 100644
--- a/include/internal/catch_interfaces_reporter.h
+++ b/include/internal/catch_interfaces_reporter.h
@@ -226,6 +226,13 @@ namespace Catch
         // Implementing class must also provide the following static method:
         // static std::string getDescription();
 
+        virtual bool supportsChainedReporters() const {
+            return false;
+        }
+
+        virtual void addChainedReporter( Ptr<IStreamingReporter> const& reporter ) {
+        }
+
         virtual ReporterPreferences getPreferences() const = 0;
 
         virtual void noMatchingTestCases( std::string const& spec ) = 0;
diff --git a/include/reporters/catch_reporter_multi.hpp b/include/reporters/catch_reporter_multi.hpp
index d3282666..9023a3f1 100644
--- a/include/reporters/catch_reporter_multi.hpp
+++ b/include/reporters/catch_reporter_multi.hpp
@@ -22,6 +22,13 @@ public:
     }
 
 public: // IStreamingReporter
+    virtual bool supportsChainedReporters() const CATCH_OVERRIDE {
+        return true;
+    }
+
+    virtual void addChainedReporter( Ptr<IStreamingReporter> const& reporter ) CATCH_OVERRIDE {
+        add( reporter );
+    }
 
     virtual ReporterPreferences getPreferences() const CATCH_OVERRIDE {
         return m_reporters[0]->getPreferences();
@@ -124,16 +131,15 @@ Ptr<IStreamingReporter> addReporter( Ptr<IStreamingReporter> const& existingRepo
     Ptr<IStreamingReporter> resultingReporter;
 
     if( existingReporter ) {
-        MultipleReporters* multi = dynamic_cast<MultipleReporters*>( existingReporter.get() );
-        if( !multi ) {
-            multi = new MultipleReporters;
+        if( !existingReporter->supportsChainedReporters() ) {
+            MultipleReporters* multi = new MultipleReporters;
             resultingReporter = Ptr<IStreamingReporter>( multi );
             if( existingReporter )
-                multi->add( existingReporter );
+                multi->addChainedReporter( existingReporter );
         }
         else
             resultingReporter = existingReporter;
-        multi->add( additionalReporter );
+        resultingReporter->addChainedReporter( additionalReporter );
     }
     else
         resultingReporter = additionalReporter;