From c9b170a05ac050cee140df67340ea158b9723d78 Mon Sep 17 00:00:00 2001
From: Chiraffollo <ollymarx@web.de>
Date: Wed, 24 Mar 2021 09:57:28 +0100
Subject: [PATCH] Add moveable parameter support to delegate (#356)

* Add moveable parameter support

* Change std::forward to etl::forward
---
 include/etl/delegate.h | 17 ++++----
 test/test_delegate.cpp | 89 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 98 insertions(+), 8 deletions(-)

diff --git a/include/etl/delegate.h b/include/etl/delegate.h
index f9ee7714..7fa1eaf7 100644
--- a/include/etl/delegate.h
+++ b/include/etl/delegate.h
@@ -52,6 +52,7 @@ Original publication: https://www.codeproject.com/Articles/1170503/The-Impossibl
 #include "error_handler.h"
 #include "exception.h"
 #include "type_traits.h"
+#include "utility.h"
 
 #if ETL_CPP11_NOT_SUPPORTED
   #if !defined(ETL_IN_UNIT_TEST)
@@ -198,7 +199,7 @@ namespace etl
     {
       ETL_ASSERT(is_valid(), ETL_ERROR(delegate_uninitialised));
 
-      return (*invocation.stub)(invocation.object, args...);
+      return (*invocation.stub)(invocation.object, etl::forward<TParams>(args)...);
     }
 
     //*************************************************************************
@@ -315,7 +316,7 @@ namespace etl
     static TReturn method_stub(void* object, TParams... params)
     {
       T* p = static_cast<T*>(object);
-      return (p->*Method)(params...);
+      return (p->*Method)(etl::forward<TParams>(params)...);
     }
 
     //*************************************************************************
@@ -325,7 +326,7 @@ namespace etl
     static TReturn const_method_stub(void* object, TParams... params)
     {
       T* const p = static_cast<T*>(object);
-      return (p->*Method)(params...);
+      return (p->*Method)(etl::forward<TParams>(params)...);
     }
 
     //*************************************************************************
@@ -334,7 +335,7 @@ namespace etl
     template <typename T, T& Instance, TReturn(T::*Method)(TParams...)>
     static TReturn method_instance_stub(void*, TParams... params)
     {
-      return (Instance.*Method)(params...);
+      return (Instance.*Method)(etl::forward<TParams>(params)...);
     }
 
     //*************************************************************************
@@ -343,7 +344,7 @@ namespace etl
     template <typename T, const T& Instance, TReturn(T::*Method)(TParams...) const>
     static TReturn const_method_instance_stub(void*, TParams... params)
     {
-      return (Instance.*Method)(params...);
+      return (Instance.*Method)(etl::forward<TParams>(params)...);
     }
 
 #if !defined(ETL_COMPILER_GCC)
@@ -353,7 +354,7 @@ namespace etl
     template <typename T, T& Instance>
     static TReturn operator_instance_stub(void*, TParams... params)
     {
-      return Instance.operator()(params...);
+      return Instance.operator()(etl::forward<TParams>(params)...);
     }
 #endif
 
@@ -363,7 +364,7 @@ namespace etl
     template <TReturn(*Method)(TParams...)>
     static TReturn function_stub(void*, TParams... params)
     {
-      return (Method)(params...);
+      return (Method)(etl::forward<TParams>(params)...);
     }
 
     //*************************************************************************
@@ -373,7 +374,7 @@ namespace etl
     static TReturn lambda_stub(void* object, TParams... arg)
     {
       TLambda* p = static_cast<TLambda*>(object);
-      return (p->operator())(arg...);
+      return (p->operator())(etl::forward<TParams>(arg)...);
     }
 
     //*************************************************************************
diff --git a/test/test_delegate.cpp b/test/test_delegate.cpp
index 917da8d0..cd8f4cd9 100644
--- a/test/test_delegate.cpp
+++ b/test/test_delegate.cpp
@@ -46,6 +46,20 @@ namespace
     int d;
   };
 
+  //*****************************************************************************
+  // Test moveable only data structure.
+  //*****************************************************************************
+  struct MoveableOnlyData
+  {
+    MoveableOnlyData() = default;
+    ~MoveableOnlyData() = default;
+    MoveableOnlyData(const MoveableOnlyData&) = delete;
+    MoveableOnlyData& operator=(const MoveableOnlyData&) = delete;
+    MoveableOnlyData(MoveableOnlyData&&) = default;
+    MoveableOnlyData& operator=(MoveableOnlyData&&) = default;
+    int d;
+  };
+
   //*****************************************************************************
   // The free function taking no parameters.
   //*****************************************************************************
@@ -72,6 +86,15 @@ namespace
     parameter_correct = (data.d == VALUE1) && (j == VALUE2);
   }
 
+  //*****************************************************************************
+  // The free function taking a moveable only parameter.
+  //*****************************************************************************
+  void free_moveableonly(MoveableOnlyData&& data)
+  {
+    function_called = true;
+    parameter_correct = (data.d == VALUE1);
+  }
+
   //*****************************************************************************
   // The test class with member functions.
   //*****************************************************************************
@@ -119,6 +142,14 @@ namespace
       parameter_correct = (data.d == VALUE1) && (j = VALUE2);
     }
 
+    //*******************************************
+    // moveable only data
+    void member_moveableonly(MoveableOnlyData&& data)
+    {
+      function_called = true;
+      parameter_correct = (data.d == VALUE1);
+    }
+
     //*******************************************
     // static
     static void member_static(const Data& data, int j)
@@ -265,6 +296,34 @@ namespace
       CHECK(parameter_correct);
     }
 
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_free_moveableonly)
+    {
+      auto d = etl::delegate<void(MoveableOnlyData&&)>::create<free_moveableonly>();
+
+      MoveableOnlyData data;
+      data.d = VALUE1;
+
+      d(std::move(data));
+
+      CHECK(function_called);
+      CHECK(parameter_correct);
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_free_moveableonly_constexpr)
+    {
+      constexpr auto d = etl::delegate<void(MoveableOnlyData&&)>::create<free_moveableonly>();
+
+      MoveableOnlyData data;
+      data.d = VALUE1;
+
+      d(std::move(data));
+
+      CHECK(function_called);
+      CHECK(parameter_correct);
+    }
+
     //*************************************************************************
     TEST_FIXTURE(SetupFixture, test_lambda_int)
     {
@@ -553,6 +612,36 @@ namespace
       CHECK(parameter_correct);
     }
 
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_member_moveableonly)
+    {
+      Test test;
+      auto d = etl::delegate<void(MoveableOnlyData&&)>::create<Test, &Test::member_moveableonly>(test);
+
+      MoveableOnlyData data;
+      data.d = VALUE1;
+
+      d(std::move(data));
+
+      CHECK(function_called);
+      CHECK(parameter_correct);
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_member_moveableonly_constexpr)
+    {
+      static Test test;
+      constexpr auto d = etl::delegate<void(MoveableOnlyData&&)>::create<Test, &Test::member_moveableonly>(test);
+
+      MoveableOnlyData data;
+      data.d = VALUE1;
+
+      d(std::move(data));
+
+      CHECK(function_called);
+      CHECK(parameter_correct);
+    }
+
     //*************************************************************************
     TEST_FIXTURE(SetupFixture, test_member_static)
     {