From 34902c481d3ef8af97a5d9094a7b7c969ec797ae Mon Sep 17 00:00:00 2001
From: Dawid Drozd <drozddawid.uam@gmail.com>
Date: Sun, 20 Jan 2019 20:39:07 +0100
Subject: [PATCH] Fix type_id<T>() helper function for Visual Studio

Issue: #19

Visual Studio optimize not so portable version of type_id<T>()
so each time we get same id for different types.

Added small test to check this behavior in future.
---
 lib/CMakeLists.txt                     |  2 +-
 lib/include/eventbus/AsyncEventBus.h   |  4 +-
 lib/include/eventbus/EventBus.h        |  6 +--
 lib/include/eventbus/internal/common.h |  9 +++--
 test/CMakeLists.txt                    |  1 +
 test/src/EventIdTest.cpp               | 53 ++++++++++++++++++++++++++
 6 files changed, 66 insertions(+), 9 deletions(-)
 create mode 100644 test/src/EventIdTest.cpp

diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index 92ec81a..d65fa6d 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -2,7 +2,7 @@ cmake_minimum_required(VERSION 3.8 FATAL_ERROR)
 
 # BUILD_SHARED_LIBS can controll build type!
 project(EventBus
-		VERSION 2.4.0
+		VERSION 2.4.1
 		LANGUAGES CXX
 		)
 
diff --git a/lib/include/eventbus/AsyncEventBus.h b/lib/include/eventbus/AsyncEventBus.h
index 2515f10..103d8d3 100644
--- a/lib/include/eventbus/AsyncEventBus.h
+++ b/lib/include/eventbus/AsyncEventBus.h
@@ -79,7 +79,7 @@ public:
 			assert(callback && "callback should be valid"); //Check for valid object
 
 			std::unique_ptr<Internal::CallbackVector>& vector =
-				_callbacks[Internal::type_id<Event>];
+				_callbacks[Internal::type_id<Event>()];
 			if(vector == nullptr)
 			{
 				vector.reset(new Vector{});
@@ -150,7 +150,7 @@ public:
 			std::lock_guard<std::mutex> guard{_callbacksMutex};
 
 			using Vector = Internal::AsyncCallbackVector<Event>;
-			auto found = _callbacks.find(Internal::type_id<Event>);
+			auto found = _callbacks.find(Internal::type_id<Event>());
 			if(found == _callbacks.end())
 			{
 				return; // no such notifications
diff --git a/lib/include/eventbus/EventBus.h b/lib/include/eventbus/EventBus.h
index a738c9b..7c20009 100644
--- a/lib/include/eventbus/EventBus.h
+++ b/lib/include/eventbus/EventBus.h
@@ -59,7 +59,7 @@ public:
 
 		assert(callback && "callback should be valid"); //Check for valid object
 
-		std::unique_ptr<Internal::CallbackVector>& vector = _callbacks[Internal::type_id<Event>];
+		std::unique_ptr<Internal::CallbackVector>& vector = _callbacks[Internal::type_id<Event>()];
 		if(vector == nullptr)
 		{
 			vector.reset(new Vector{});
@@ -89,7 +89,7 @@ public:
 	{
 		static_assert(Internal::validateEvent<Event>(), "Invalid event");
 
-		auto found = _callbacks.find(Internal::type_id<Event>);
+		auto found = _callbacks.find(Internal::type_id<Event>());
 		if(found != _callbacks.end())
 		{
 			found->second->remove(token);
@@ -108,7 +108,7 @@ public:
 		static_assert(Internal::validateEvent<Event>(), "Invalid event");
 
 		using Vector = Internal::TransactionCallbackVector<CleanEventType>;
-		auto found = _callbacks.find(Internal::type_id<CleanEventType>);
+		auto found = _callbacks.find(Internal::type_id<CleanEventType>());
 		if(found == _callbacks.end())
 		{
 			return; // no such notifications
diff --git a/lib/include/eventbus/internal/common.h b/lib/include/eventbus/internal/common.h
index 1a37916..7a4bd3f 100644
--- a/lib/include/eventbus/internal/common.h
+++ b/lib/include/eventbus/internal/common.h
@@ -7,12 +7,15 @@ namespace Dexode
 namespace Internal
 {
 
-template <typename>
-void type_id() // Helper for getting "type id"
+using type_id_t = std::size_t;
+
+template <typename T>
+type_id_t type_id() // Helper for getting "type id"
 {
+	return typeid(T).hash_code();
 }
 
-using type_id_t = void (*)(); // Function pointer
+
 
 template <class Event>
 constexpr bool validateEvent()
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index bf21ce9..c87cabb 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -21,6 +21,7 @@ find_package(Threads REQUIRED)
 add_executable(EventBusTest
 	src/AsyncEventBusTest.cpp
 	src/EventCollectorTest.cpp
+	src/EventIdTest.cpp
 	src/NotifierTest.cpp
 	)
 
diff --git a/test/src/EventIdTest.cpp b/test/src/EventIdTest.cpp
new file mode 100644
index 0000000..369bb2a
--- /dev/null
+++ b/test/src/EventIdTest.cpp
@@ -0,0 +1,53 @@
+#include <catch2/catch.hpp>
+
+#include <set>
+
+#include <eventbus/internal/common.h>
+
+namespace
+{
+struct Anonymous
+{};
+} // namespace
+
+struct TestA
+{
+	int a;
+};
+
+namespace Test
+{
+struct TestA
+{
+	bool b;
+};
+
+namespace TestN
+{
+struct TestA
+{
+	long long c;
+};
+
+} // namespace TestN
+
+} // namespace Test
+
+TEST_CASE("Should return unique id for each event When using Internal::type_id<Event>", "[EventId]")
+{
+	std::set<Dexode::Internal::type_id_t> unique;
+
+	REQUIRE(unique.insert(Dexode::Internal::type_id<Anonymous>()).second);
+	REQUIRE_FALSE(unique.insert(Dexode::Internal::type_id<Anonymous>()).second); //already there
+
+	struct TestA
+	{};
+
+	::TestA a;
+	a.a = 10;
+
+	REQUIRE(unique.insert(Dexode::Internal::type_id<TestA>()).second);
+	REQUIRE(unique.insert(Dexode::Internal::type_id<::TestA>()).second);
+	REQUIRE(unique.insert(Dexode::Internal::type_id<Test::TestA>()).second);
+	REQUIRE(unique.insert(Dexode::Internal::type_id<Test::TestN::TestA>()).second);
+}