From 6b4bd70c587ca533ceec4400deb4b36f6e8aa817 Mon Sep 17 00:00:00 2001
From: Yohan Bainier <y.bainier@abc-arbitrage.com>
Date: Fri, 23 Sep 2016 15:59:34 +0200
Subject: [PATCH] AsSelf can no longer be applied to a registration which
 instance type is not registered as other type(s)/alias(es)

---
 Hypodermic/AsSelf.h | 32 +++++++++++++++++++++++++++++---
 1 file changed, 29 insertions(+), 3 deletions(-)

diff --git a/Hypodermic/AsSelf.h b/Hypodermic/AsSelf.h
index 5e8d0a2..5cc6a64 100644
--- a/Hypodermic/AsSelf.h
+++ b/Hypodermic/AsSelf.h
@@ -7,12 +7,38 @@ namespace Hypodermic
 {
 namespace RegistrationDescriptorOperations
 {
+    
+    namespace Details
+    {
+
+        struct InstanceRegistrationNotResolvable {};
+        struct InstanceRegistrationResolvable {};
+        
+        template <class TDescriptorInfo>
+        struct GetInstanceRegistrationResolvability
+        {
+        private:
+            typedef typename TDescriptorInfo::RegisteredBases RegisteredBases;
+            typedef typename TDescriptorInfo::InstanceRegistrationTag InstanceRegistrationTag;
+
+        public:
+            typedef typename std::conditional
+            <
+                (RegisteredBases::count == 0) || std::is_same< InstanceRegistrationTag, Tags::SelfRegistered >::value,
+                InstanceRegistrationResolvable,
+                InstanceRegistrationNotResolvable
+            >
+            ::type Type;
+        };
+
+    } // namespace Details
+
 
     template
     <
         class TDescriptor,
         class TDescriptorInfo,
-        class TInstanceRegistrationTag = typename TDescriptorInfo::InstanceRegistrationTag
+        class TInstanceRegistrationResolvability = typename Details::GetInstanceRegistrationResolvability< TDescriptorInfo >::Type
     >
     class AsSelf;
 
@@ -22,7 +48,7 @@ namespace RegistrationDescriptorOperations
         class TDescriptor,
         class TDescriptorInfo
     >
-    class AsSelf< TDescriptor, TDescriptorInfo, Tags::NotSelfRegistered >
+    class AsSelf< TDescriptor, TDescriptorInfo, Details::InstanceRegistrationNotResolvable >
     {
     public:
         // This template avoids Early Template Instantiation issue
@@ -52,7 +78,7 @@ namespace RegistrationDescriptorOperations
         class TDescriptor,
         class TDescriptorInfo
     >
-    class AsSelf< TDescriptor, TDescriptorInfo, Tags::SelfRegistered >
+    class AsSelf< TDescriptor, TDescriptorInfo, Details::InstanceRegistrationResolvable >
     {
     protected:
         virtual ~AsSelf() {}