From 173aa3f1f401ce1165ec9307d249dc506a976c3e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Ho=C5=99e=C5=88ovsk=C3=BD?=
 <martin.horenovsky@gmail.com>
Date: Thu, 16 Mar 2023 10:04:03 +0100
Subject: [PATCH] Devirtualize Context

---
 src/catch2/internal/catch_context.cpp | 52 ++++++++-------------------
 src/catch2/internal/catch_context.hpp | 47 +++++++++++-------------
 2 files changed, 35 insertions(+), 64 deletions(-)

diff --git a/src/catch2/internal/catch_context.cpp b/src/catch2/internal/catch_context.cpp
index 17f28509..3b1cc277 100644
--- a/src/catch2/internal/catch_context.cpp
+++ b/src/catch2/internal/catch_context.cpp
@@ -11,49 +11,27 @@
 
 namespace Catch {
 
-    class Context : public IMutableContext, private Detail::NonCopyable {
+    Context* Context::currentContext = nullptr;
 
-    public: // IContext
-        IResultCapture* getResultCapture() override {
-            return m_resultCapture;
-        }
-
-        IConfig const* getConfig() const override {
-            return m_config;
-        }
-
-        ~Context() override;
-
-    public: // IMutableContext
-        void setResultCapture( IResultCapture* resultCapture ) override {
-            m_resultCapture = resultCapture;
-        }
-        void setConfig( IConfig const* config ) override {
-            m_config = config;
-        }
-
-        friend IMutableContext& getCurrentMutableContext();
-
-    private:
-        IConfig const* m_config = nullptr;
-        IResultCapture* m_resultCapture = nullptr;
-    };
-
-    IMutableContext *IMutableContext::currentContext = nullptr;
-
-    void IMutableContext::createContext()
-    {
+    void cleanUpContext() {
+        delete Context::currentContext;
+        Context::currentContext = nullptr;
+    }
+    void Context::createContext() {
         currentContext = new Context();
     }
 
-    void cleanUpContext() {
-        delete IMutableContext::currentContext;
-        IMutableContext::currentContext = nullptr;
+    Context& getCurrentMutableContext() {
+        if ( !Context::currentContext ) { Context::createContext(); }
+        // NOLINTNEXTLINE(clang-analyzer-core.uninitialized.UndefReturn)
+        return *Context::currentContext;
     }
-    IContext::~IContext() = default;
-    IMutableContext::~IMutableContext() = default;
-    Context::~Context() = default;
 
+    void Context::setResultCapture( IResultCapture* resultCapture ) {
+        m_resultCapture = resultCapture;
+    }
+
+    void Context::setConfig( IConfig const* config ) { m_config = config; }
 
     SimplePcg32& sharedRng() {
         static SimplePcg32 s_rng;
diff --git a/src/catch2/internal/catch_context.hpp b/src/catch2/internal/catch_context.hpp
index a9d1b394..6ccb3b31 100644
--- a/src/catch2/internal/catch_context.hpp
+++ b/src/catch2/internal/catch_context.hpp
@@ -15,38 +15,31 @@ namespace Catch {
     class IResultCapture;
     class IConfig;
 
-    class IContext {
-    public:
-        virtual ~IContext(); // = default
+    class Context {
+        IConfig const* m_config = nullptr;
+        IResultCapture* m_resultCapture = nullptr;
 
-        virtual IResultCapture* getResultCapture() = 0;
-        virtual IConfig const* getConfig() const = 0;
-    };
-
-    class IMutableContext : public IContext {
-    public:
-        ~IMutableContext() override; // = default
-        virtual void setResultCapture( IResultCapture* resultCapture ) = 0;
-        virtual void setConfig( IConfig const* config ) = 0;
-
-    private:
-        CATCH_EXPORT static IMutableContext* currentContext;
-        friend IMutableContext& getCurrentMutableContext();
-        friend void cleanUpContext();
+        CATCH_EXPORT static Context* currentContext;
+        friend Context& getCurrentMutableContext();
+        friend Context const& getCurrentContext();
         static void createContext();
+        friend void cleanUpContext();
+
+    public:
+        IResultCapture* getResultCapture() const { return m_resultCapture; }
+        IConfig const* getConfig() const { return m_config; }
+        void setResultCapture( IResultCapture* resultCapture );
+        void setConfig( IConfig const* config );
     };
 
-    inline IMutableContext& getCurrentMutableContext()
-    {
-        if( !IMutableContext::currentContext )
-            IMutableContext::createContext();
-        // NOLINTNEXTLINE(clang-analyzer-core.uninitialized.UndefReturn)
-        return *IMutableContext::currentContext;
-    }
+    Context& getCurrentMutableContext();
 
-    inline IContext& getCurrentContext()
-    {
-        return getCurrentMutableContext();
+    inline Context const& getCurrentContext() {
+        // We duplicate the logic from `getCurrentMutableContext` here,
+        // to avoid paying the call overhead in debug mode.
+        if ( !Context::currentContext ) { Context::createContext(); }
+        // NOLINTNEXTLINE(clang-analyzer-core.uninitialized.UndefReturn)
+        return *Context::currentContext;
     }
 
     void cleanUpContext();