add a DISABLE_LUA compile option

SConstruct

@@ -60,6 +60,7 @@ opts.AddVariables(
     PathVariable('python_site_packages_dir', 'sets the directory where python modules are installed', "lib/python/site-packages/wesnoth", PathVariable.PathAccept),
     BoolVariable('editor', 'Enable editor', True),
     BoolVariable('lowmem', 'Set to reduce memory usage by removing extra functionality', False),
+    BoolVariable('lua', 'Enable Lua support', True),
     BoolVariable('nls','enable compile/install of gettext message catalogs',True),
     PathVariable('prefix', 'autotools-style installation prefix', "/usr/local", PathVariable.PathAccept),
     PathVariable('prefsdir', 'user preferences directory', ".wesnoth$version_suffix", PathVariable.PathAccept),
@@ -317,6 +318,9 @@ for env in [test_env, env]:
     if not env["editor"]:
         env.Append(CPPDEFINES = "DISABLE_EDITOR2")
 
+    if not env['lua']:
+        env.Append(CPPDEFINES = "DISABLE_LUA")
+
     if env["PLATFORM"] == "win32":
         env["pool_alloc"] = False
 

src/scripting/lua.cpp

@@ -22,6 +22,16 @@
  *   to force object unscoping before erroring out.
  */
 
+#ifdef DISABLE_LUA
+#include "scripting/lua.hpp"
+LuaKernel::LuaKernel() {std::cerr <<"NOTE: Lua support disabled in this build";}
+LuaKernel::~LuaKernel() {}
+void LuaKernel::run_event(vconfig const &cfg, game_events::queued_event const &ev,
+	game_events::event_handler *handler, unit_map *units) {}
+void LuaKernel::run(char const *prog) {}
+void LuaKernel::execute(char const *prog, int nArgs, int nRets) {}
+#else  // HAVE LUA
+
 extern "C" {
 #include <lualib.h>
 #include <lauxlib.h>
@@ -700,3 +710,6 @@ void LuaKernel::execute(char const *prog, int nArgs, int nRets)
 
 	lua_remove(L, -1 - nRets);
 }
+
+#endif // HAVE LUA
+