From 8188d29a587cab9d4593ff0c9f29d8ed4592a9cd Mon Sep 17 00:00:00 2001
From: _Redstone_c_ <myredstone1024@gmail.com>
Date: Tue, 15 Mar 2022 14:25:06 +0800
Subject: [PATCH] feat(typetraits): add TypeTraits/CopyQualifiers.h and the
 corresponding testing

---
 .../Private/Testing/TypeTraitsTesting.cpp     | 78 +++++++++++++++++++
 .../Source/Public/TypeTraits/CopyQualifiers.h | 36 +++++++++
 .../Source/Public/TypeTraits/TypeTraits.h     |  1 +
 3 files changed, 115 insertions(+)
 create mode 100644 Redcraft.Utility/Source/Public/TypeTraits/CopyQualifiers.h

diff --git a/Redcraft.Utility/Source/Private/Testing/TypeTraitsTesting.cpp b/Redcraft.Utility/Source/Private/Testing/TypeTraitsTesting.cpp
index 2e0e5cd..23933af 100644
--- a/Redcraft.Utility/Source/Private/Testing/TypeTraitsTesting.cpp
+++ b/Redcraft.Utility/Source/Private/Testing/TypeTraitsTesting.cpp
@@ -450,6 +450,84 @@ void TestTypeTraits()
 
 	always_check((TIsSwappableWith<int32&, int32&>::Value));
 
+	// CopyQualifiers.h
+
+	always_check((TIsSame<               int32, TCopyConst<               int32,                int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyConst<const          int32,                int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyConst<const volatile int32,                int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyConst<               int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyConst<const          int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyConst<const volatile int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyConst<               int32, const volatile int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyConst<const          int32, const volatile int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyConst<const volatile int32, const volatile int32>::Type>::Value));
+	
+	always_check((TIsSame<               int32, TCopyVolatile<               int32,                int32>::Type>::Value));
+	always_check((TIsSame<               int32, TCopyVolatile<const          int32,                int32>::Type>::Value));
+	always_check((TIsSame<      volatile int32, TCopyVolatile<const volatile int32,                int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyVolatile<               int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyVolatile<const          int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyVolatile<const volatile int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyVolatile<               int32, const volatile int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyVolatile<const          int32, const volatile int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyVolatile<const volatile int32, const volatile int32>::Type>::Value));
+	
+	always_check((TIsSame<               int32, TCopyCV<               int32,                int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyCV<const          int32,                int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyCV<const volatile int32,                int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyCV<               int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyCV<const          int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyCV<const volatile int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyCV<               int32, const volatile int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyCV<const          int32, const volatile int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyCV<const volatile int32, const volatile int32>::Type>::Value));
+	
+	always_check((TIsSame<int32,   TCopyReference<int32,   int32  >::Type>::Value));
+	always_check((TIsSame<int32&,  TCopyReference<int32,   int32& >::Type>::Value));
+	always_check((TIsSame<int32&&, TCopyReference<int32,   int32&&>::Type>::Value));
+	always_check((TIsSame<int32&,  TCopyReference<int32&,  int32  >::Type>::Value));
+	always_check((TIsSame<int32&,  TCopyReference<int32&,  int32& >::Type>::Value));
+	always_check((TIsSame<int32&,  TCopyReference<int32&,  int32&&>::Type>::Value));
+	always_check((TIsSame<int32&&, TCopyReference<int32&&, int32  >::Type>::Value));
+	always_check((TIsSame<int32&,  TCopyReference<int32&&, int32& >::Type>::Value));
+	always_check((TIsSame<int32&&, TCopyReference<int32&&, int32&&>::Type>::Value));
+
+	always_check((TIsSame<               int32, TCopyCVRef<               int32,                int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyCVRef<const          int32,                int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyCVRef<               int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyCVRef<const          int32, const          int32>::Type>::Value));
+	always_check((TIsSame<      volatile int32, TCopyCVRef<      volatile int32,                int32>::Type>::Value));
+	always_check((TIsSame<      volatile int32, TCopyCVRef<               int32,       volatile int32>::Type>::Value));
+	always_check((TIsSame<      volatile int32, TCopyCVRef<      volatile int32,       volatile int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyCVRef<const          int32,                int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyCVRef<const volatile int32,                int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyCVRef<               int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const          int32, TCopyCVRef<const          int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyCVRef<const volatile int32, const          int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyCVRef<               int32, const volatile int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyCVRef<const          int32, const volatile int32>::Type>::Value));
+	always_check((TIsSame<const volatile int32, TCopyCVRef<const volatile int32, const volatile int32>::Type>::Value));
+	
+	always_check((TIsSame<int32,   TCopyCVRef<int32,   int32  >::Type>::Value));
+	always_check((TIsSame<int32&,  TCopyCVRef<int32,   int32& >::Type>::Value));
+	always_check((TIsSame<int32&&, TCopyCVRef<int32,   int32&&>::Type>::Value));
+	always_check((TIsSame<int32&,  TCopyCVRef<int32&,  int32  >::Type>::Value));
+	always_check((TIsSame<int32&,  TCopyCVRef<int32&,  int32& >::Type>::Value));
+	always_check((TIsSame<int32&,  TCopyCVRef<int32&,  int32&&>::Type>::Value));
+	always_check((TIsSame<int32&&, TCopyCVRef<int32&&, int32  >::Type>::Value));
+	always_check((TIsSame<int32&,  TCopyCVRef<int32&&, int32& >::Type>::Value));
+	always_check((TIsSame<int32&&, TCopyCVRef<int32&&, int32&&>::Type>::Value));
+
+	always_check((TIsSame<const           int32,   TCopyCVRef<const          int32,         int32  >::Type>::Value));
+	always_check((TIsSame<const           int32&,  TCopyCVRef<               int32,   const int32& >::Type>::Value));
+	always_check((TIsSame<const volatile  int32&&, TCopyCVRef<const volatile int32,   const int32&&>::Type>::Value));
+	always_check((TIsSame<const           int32&,  TCopyCVRef<const          int32&,        int32  >::Type>::Value));
+	always_check((TIsSame<const           int32&,  TCopyCVRef<const          int32&,  const int32& >::Type>::Value));
+	always_check((TIsSame<const volatile  int32&,  TCopyCVRef<      volatile int32&,  const int32&&>::Type>::Value));
+	always_check((TIsSame<const           int32&&, TCopyCVRef<const          int32&&,       int32  >::Type>::Value));
+	always_check((TIsSame<const           int32&,  TCopyCVRef<const          int32&&, const int32& >::Type>::Value));
+	always_check((TIsSame<const volatile  int32&&, TCopyCVRef<const volatile int32&&, const int32&&>::Type>::Value));
+
 }
 
 NAMESPACE_MODULE_END(Utility)
diff --git a/Redcraft.Utility/Source/Public/TypeTraits/CopyQualifiers.h b/Redcraft.Utility/Source/Public/TypeTraits/CopyQualifiers.h
new file mode 100644
index 0000000..588082b
--- /dev/null
+++ b/Redcraft.Utility/Source/Public/TypeTraits/CopyQualifiers.h
@@ -0,0 +1,36 @@
+#pragma once
+
+#include "CoreTypes.h"
+#include "TypeTraits/HelperClasses.h"
+
+#include <type_traits>
+
+NAMESPACE_REDCRAFT_BEGIN
+NAMESPACE_MODULE_BEGIN(Redcraft)
+NAMESPACE_MODULE_BEGIN(Utility)
+
+template <typename From, typename To> struct TCopyConst                 { using Type =       To; };
+template <typename From, typename To> struct TCopyConst<const From, To> { using Type = const To; };
+
+template <typename From, typename To> struct TCopyVolatile                    { using Type =          To; };
+template <typename From, typename To> struct TCopyVolatile<volatile From, To> { using Type = volatile To; };
+
+template <typename From, typename To> struct TCopyCV { using Type = typename TCopyConst<From, typename TCopyVolatile<From, To>::Type>::Type; };
+
+template <typename From, typename To> struct TCopyReference               { using Type = To;   };
+template <typename From, typename To> struct TCopyReference<From&,  To  > { using Type = To&;  };
+template <typename From, typename To> struct TCopyReference<From&&, To  > { using Type = To&&; };
+
+template <typename From, typename To> struct TCopyCVRef               { using Type = typename TCopyCV<From, To>::Type;   };
+template <typename From, typename To> struct TCopyCVRef<From,   To& > { using Type = typename TCopyCV<From, To>::Type&;  };
+template <typename From, typename To> struct TCopyCVRef<From,   To&&> { using Type = typename TCopyCV<From, To>::Type&&; };
+template <typename From, typename To> struct TCopyCVRef<From&,  To  > { using Type = typename TCopyCV<From, To>::Type&;  };
+template <typename From, typename To> struct TCopyCVRef<From&,  To& > { using Type = typename TCopyCV<From, To>::Type&;  };
+template <typename From, typename To> struct TCopyCVRef<From&,  To&&> { using Type = typename TCopyCV<From, To>::Type&;  };
+template <typename From, typename To> struct TCopyCVRef<From&&, To  > { using Type = typename TCopyCV<From, To>::Type&&; };
+template <typename From, typename To> struct TCopyCVRef<From&&, To& > { using Type = typename TCopyCV<From, To>::Type&;  };
+template <typename From, typename To> struct TCopyCVRef<From&&, To&&> { using Type = typename TCopyCV<From, To>::Type&&; };
+
+NAMESPACE_MODULE_END(Utility)
+NAMESPACE_MODULE_END(Redcraft)
+NAMESPACE_REDCRAFT_END
diff --git a/Redcraft.Utility/Source/Public/TypeTraits/TypeTraits.h b/Redcraft.Utility/Source/Public/TypeTraits/TypeTraits.h
index 0c02e41..8ed0163 100644
--- a/Redcraft.Utility/Source/Public/TypeTraits/TypeTraits.h
+++ b/Redcraft.Utility/Source/Public/TypeTraits/TypeTraits.h
@@ -9,3 +9,4 @@
 #include "TypeTraits/Miscellaneous.h"
 #include "TypeTraits/Swappable.h"
 #include "TypeTraits/Common.h"
+#include "TypeTraits/CopyQualifiers.h"