[Lua] Fix type resolution between SWIG-wrapped modules

See #2126

CHANGES.current

@@ -7,6 +7,10 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.1.0 (in progress)
 ===========================
 
+2022-10-19: olly
+	    [Lua] #2126 Fix type resolution between multiple SWIG-wrapped
+	    modules.
+
 2022-10-17: wsfulton
             [R] #2385 Add support for std::vector<std::vector<std::string>>.
 

Examples/test-suite/lua/mod_runme.lua

@@ -0,0 +1,12 @@
+require("import")	-- the import fn
+import("mod_a")	-- import lib
+import("mod_b")	-- import lib
+
+-- catch "undefined" global variables
+local env = _ENV -- Lua 5.2
+if not env then env = getfenv () end -- Lua 5.1
+setmetatable(env, {__index=function (t,i) error("undefined global variable `"..i.."'",2) end})
+
+c = mod_b.C()
+d = mod_b.D()
+d:DoSomething(c)

Lib/lua/luarun.swg

@@ -1789,7 +1789,7 @@ SWIGRUNTIME int  SWIG_Lua_ConvertPtr(lua_State *L,int index,void **ptr,swig_type
     }
     else
     {
-      cast=SWIG_TypeCheckStruct(usr->type,type); /* performs normal type checking */
+      cast=SWIG_TypeCheck(usr->type->name,type); /* performs normal type checking */
       if (cast)
       {
         int newmemory = 0;