From 33c59614fc55d6ef8404b609836dee75db69bd38 Mon Sep 17 00:00:00 2001
From: Ryan Nevell <rnevell@apple.com>
Date: Mon, 17 Feb 2020 08:45:42 -0800
Subject: [PATCH] Fix unwrapping of LUA lightuserdata type. Add test case.

---
 Examples/test-suite/lua/Makefile.in              |  1 +
 .../test-suite/lua/lua_lightuserdata_runme.lua   |  7 +++++++
 Examples/test-suite/lua_lightuserdata.i          | 16 ++++++++++++++++
 Lib/lua/luarun.swg                               |  5 +++++
 4 files changed, 29 insertions(+)
 create mode 100644 Examples/test-suite/lua/lua_lightuserdata_runme.lua
 create mode 100644 Examples/test-suite/lua_lightuserdata.i

diff --git a/Examples/test-suite/lua/Makefile.in b/Examples/test-suite/lua/Makefile.in
index 63b8692b1..92559bb8f 100644
--- a/Examples/test-suite/lua/Makefile.in
+++ b/Examples/test-suite/lua/Makefile.in
@@ -15,6 +15,7 @@ top_builddir = @top_builddir@
 CPP_TEST_CASES += \
 	lua_no_module_global \
 	lua_inherit_getitem  \
+	lua_lightuserdata  \
 
 
 C_TEST_CASES += \
diff --git a/Examples/test-suite/lua/lua_lightuserdata_runme.lua b/Examples/test-suite/lua/lua_lightuserdata_runme.lua
new file mode 100644
index 000000000..d805c2a74
--- /dev/null
+++ b/Examples/test-suite/lua/lua_lightuserdata_runme.lua
@@ -0,0 +1,7 @@
+require("import") -- the import fn
+require("lua_lightuserdata") -- import lib
+
+local t = lua_lightuserdata
+local d = t.get_lightuserdata()
+local r = t.check_lighuserdata(d)
+assert(r)
diff --git a/Examples/test-suite/lua_lightuserdata.i b/Examples/test-suite/lua_lightuserdata.i
new file mode 100644
index 000000000..08e15c93c
--- /dev/null
+++ b/Examples/test-suite/lua_lightuserdata.i
@@ -0,0 +1,16 @@
+%module lua_lightuserdata
+
+%native(get_lightuserdata) int get_lightuserdata(lua_State* L);
+%{
+int get_lightuserdata(lua_State* L)
+{
+  lua_pushlightuserdata(L, reinterpret_cast<void*>(0x123456));
+  return 1;
+}
+%}
+
+%inline %{
+bool check_lighuserdata(const void* d) {
+  return reinterpret_cast<void*>(0x123456) == d;
+}
+%}
diff --git a/Lib/lua/luarun.swg b/Lib/lua/luarun.swg
index bd764d668..b8ddf000a 100644
--- a/Lib/lua/luarun.swg
+++ b/Lib/lua/luarun.swg
@@ -1765,6 +1765,11 @@ SWIGRUNTIME int  SWIG_Lua_ConvertPtr(lua_State *L,int index,void **ptr,swig_type
     *ptr=0;
     return (flags & SWIG_POINTER_NO_NULL) ? SWIG_NullReferenceError : SWIG_OK;
   }
+  if (lua_islightuserdata(L,index))
+  {
+    *ptr=lua_touserdata(L,index);
+    return (flags & SWIG_POINTER_NO_NULL) ? SWIG_NullReferenceError : SWIG_OK;
+  }
   usr=(swig_lua_userdata*)lua_touserdata(L,index);  /* get data */
   if (usr)
   {