Pressure plates : fix set_node being called twice + some other fixes

mechanisms.lua

@@ -6,11 +6,17 @@ local function door_toggle(pos_actuator, pos_door, player)
 	local actuator = minetest.get_node(pos_actuator)
 	local door = doors.get(pos_door)
 
-	minetest.set_node(pos_actuator, {name=actuator.name:gsub("_off", "_on"), param2=actuator.param2})
+	if actuator.name:sub(-4) == "_off" then
+		minetest.set_node(pos_actuator,
+			{name=actuator.name:gsub("_off", "_on"), param2=actuator.param2})
+	end
 	door:open(player)
 
 	minetest.after(2, function()
-		minetest.set_node(pos_actuator, {name=actuator.name, param2=actuator.param2})
+		if minetest.get_node(pos_actuator).name:sub(-3) == "_on" then
+			minetest.set_node(pos_actuator,
+				{name=actuator.name, param2=actuator.param2})
+		end
 		door:close(player)
 	end)
 end
@@ -32,6 +38,7 @@ function plate.timer(pos)
 			for i = 1, #doors do
 				door_toggle(pos, doors[i], player)
 			end
+			break
 		end
 	end
 	return true