From cd092d3bfb8465835526e1f171d9432f8992172b Mon Sep 17 00:00:00 2001
From: Rapptz <rapptz@gmail.com>
Date: Sun, 27 Apr 2014 05:09:28 -0400
Subject: [PATCH] Add new_userdata to create internally memory managed userdata
 from sol::state

---
 sol/state.hpp | 11 +++++++++++
 tests.cpp     | 27 ++++++++++++++++++++++++++-
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/sol/state.hpp b/sol/state.hpp
index 5453c5c2..3f47322c 100644
--- a/sol/state.hpp
+++ b/sol/state.hpp
@@ -56,6 +56,7 @@ enum class lib : char {
 
 class state {
 private:
+    std::vector<std::shared_ptr<void>> classes;
     std::unique_ptr<lua_State, void(*)(lua_State*)> L;
     table reg;
     table global;
@@ -156,6 +157,16 @@ public:
         return *this;
     }
 
+    template<typename Class, typename... CTor, typename... Args>
+    state& new_userdata(const std::string& name, Args&&... args) {
+        constructors<types<CTor...>> ctor;
+        classes.emplace_back(std::make_shared<userdata<Class>>(name, ctor, std::forward<Args>(args)...));
+        auto&& ptr = classes.back();
+        auto udata = std::static_pointer_cast<userdata<Class>>(ptr);
+        global.set_userdata(*udata);
+        return *this;
+    }
+
     template<typename T>
     table create_table(T&& key, int narr = 0, int nrec = 0) {
         lua_createtable(L.get(), narr, nrec);
diff --git a/tests.cpp b/tests.cpp
index d4792538..0c76980c 100644
--- a/tests.cpp
+++ b/tests.cpp
@@ -422,4 +422,29 @@ TEST_CASE("tables/userdata constructors", "Show that we can create classes from
     sol::object z = lua.get<sol::object>("z");
     REQUIRE((y.as<int>() == 7));
     REQUIRE((z.as<int>() == 9));
-}
\ No newline at end of file
+}
+
+TEST_CASE("tables/userdata utility", "Show internal management of classes registered through new_userdata") {
+    sol::state lua;
+
+    lua.new_userdata<fuser>("fuser", "add", &fuser::add, "add2", &fuser::add2);
+
+    lua.script("a = fuser.new()\n"
+               "b = a:add(1)\n"
+               "c = a:add2(1)\n");
+
+    sol::object a = lua.get<sol::object>("a");
+    sol::object b = lua.get<sol::object>("b");
+    sol::object c = lua.get<sol::object>("c");
+    REQUIRE((a.is<sol::userdata_t>()));
+    auto atype = a.get_type();
+    auto btype = b.get_type();
+    auto ctype = c.get_type();
+    REQUIRE((atype == sol::type::userdata));
+    REQUIRE((btype == sol::type::number));
+    REQUIRE((ctype == sol::type::number));
+    int bresult = b.as<int>();
+    int cresult = c.as<int>();
+    REQUIRE(bresult == 1);
+    REQUIRE(cresult == 3);
+}