Report oldstack correctly (before mutation)

mesecons_mvps/init.lua

@@ -220,6 +220,8 @@ function mesecon.mvps_push_or_pull(pos, stackdir, movedir, maximum, all_pull_sti
 		minetest.remove_node(n.pos)
 	end
 
+	local oldstack = mesecon.tablecopy(nodes)
+
 	-- update mesecons for removed nodes ( has to be done after all nodes have been removed )
 	for _, n in ipairs(nodes) do
 		mesecon.on_dignode(n.pos, n.node)
@@ -243,7 +245,6 @@ function mesecon.mvps_push_or_pull(pos, stackdir, movedir, maximum, all_pull_sti
 	end
 
 	local moved_nodes = {}
-	local oldstack = mesecon.tablecopy(nodes)
 	for i in ipairs(nodes) do
 		moved_nodes[i] = {}
 		moved_nodes[i].oldpos = nodes[i].pos