From f63c3072a45d59d94d15918afe65db587eabdbed Mon Sep 17 00:00:00 2001
From: jacob1 <jfu614@gmail.com>
Date: Fri, 11 Dec 2015 12:05:00 -0500
Subject: [PATCH] fix crash when doing simulation = nil in the console

---
 src/lua/LuaScriptInterface.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/lua/LuaScriptInterface.cpp b/src/lua/LuaScriptInterface.cpp
index 9edcc8508..059a6856d 100644
--- a/src/lua/LuaScriptInterface.cpp
+++ b/src/lua/LuaScriptInterface.cpp
@@ -3313,7 +3313,11 @@ bool LuaScriptInterface::OnMouseTick()
 void LuaScriptInterface::OnTick()
 {
 	lua_getglobal(l, "simulation");
-	lua_pushinteger(l, luacon_sim->NUM_PARTS); lua_setfield(l, -2, "NUM_PARTS");
+	if (lua_istable(l, -1))
+	{
+		lua_pushinteger(l, luacon_sim->NUM_PARTS);
+		lua_setfield(l, -2, "NUM_PARTS");
+	}
 	lua_pop(l, 1);
 	ui::Engine::Ref().LastTick(Platform::GetTime());
 	luacon_step(luacon_mousex, luacon_mousey);