From 1d255d1d5f55584626ae247610f379ccdb8f2ec5 Mon Sep 17 00:00:00 2001
From: valid-ptr <konstantin.matveyev@eligovision.ru>
Date: Mon, 15 Feb 2021 16:24:54 +0300
Subject: Bug fix for Lua 5.1/LuaJIT: lua_getiuservalue must check if
 lua_getfenv returns global environment

---
 src/compat.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

(limited to 'src')

diff --git a/src/compat.c b/src/compat.c
index 9f36090..bccd05f 100644
--- a/src/compat.c
+++ b/src/compat.c
@@ -59,6 +59,20 @@ int lua_getiuservalue( lua_State* L, int idx, int n)
 		return LUA_TNONE;
 	}
 	lua_getuservalue( L, idx);
+
+#if LUA_VERSION_NUM == 501
+	/* default environment is not a nil (see lua_getfenv) */
+	lua_getglobal(L, "package");
+	if (lua_rawequal(L, -2, -1) || lua_rawequal(L, -2, LUA_GLOBALSINDEX))
+	{
+		lua_pop(L, 2);
+		lua_pushnil( L);
+
+		return LUA_TNONE;
+	}
+	lua_pop(L, 1);	/* remove package */
+#endif
+
 	return lua_type( L, -1);
 }
 
-- 
cgit v1.2.3-55-g6feb