Adds Custom Milj Option to Udders (tgstation#61224)

code/datums/components/udder.dm

@@ -9,10 +9,11 @@
 	///optional proc to callback to when the udder is milked
 	var/datum/callback/on_milk_callback
 
-/datum/component/udder/Initialize(udder_type = /obj/item/udder, on_milk_callback, on_generate_callback)
+//udder_type and reagent_produced_typepath are typepaths, not reference
+/datum/component/udder/Initialize(udder_type = /obj/item/udder, on_milk_callback, on_generate_callback, reagent_produced_typepath = /datum/reagent/consumable/milk)
 	if(!isliving(parent)) //technically is possible to drop this on carbons... but you wouldn't do that to me, would you?
 		return COMPONENT_INCOMPATIBLE
-	udder = new udder_type(null, parent, on_generate_callback)
+	udder = new udder_type(null, parent, on_generate_callback, reagent_produced_typepath)
 	src.on_milk_callback = on_milk_callback
 
 /datum/component/udder/RegisterWithParent()
@@ -60,17 +61,20 @@
  */
 /obj/item/udder
 	name = "udder"
+	///typepath of reagent produced by the udder
+	var/reagent_produced_typepath = /datum/reagent/consumable/milk
 	///how much the udder holds
 	var/size = 50
 	///mob that has the udder component
 	var/mob/living/udder_mob
 	///optional proc to callback to when the udder generates milk
 	var/datum/callback/on_generate_callback
 
-/obj/item/udder/Initialize(mapload, udder_mob, on_generate_callback)
+/obj/item/udder/Initialize(mapload, udder_mob, on_generate_callback, reagent_produced_typepath = /datum/reagent/consumable/milk)
 	src.udder_mob = udder_mob
 	src.on_generate_callback = on_generate_callback
 	create_reagents(size, REAGENT_HOLDER_ALIVE)
+	src.reagent_produced_typepath = reagent_produced_typepath
 	initial_conditions()
 	. = ..()
 
@@ -88,15 +92,15 @@
  * also useful for changing initial amounts in reagent holder (cows start with milk, gutlunches start empty)
  */
 /obj/item/udder/proc/initial_conditions()
-	reagents.add_reagent(/datum/reagent/consumable/milk, 20)
+	reagents.add_reagent(reagent_produced_typepath, 20)
 	START_PROCESSING(SSobj, src)
 
 /**
  * Proc called every 2 seconds from SSMobs to add whatever reagent the udder is generating.
  */
 /obj/item/udder/proc/generate()
 	if(prob(5))
-		reagents.add_reagent(/datum/reagent/consumable/milk, rand(5, 10))
+		reagents.add_reagent(reagent_produced_typepath, rand(5, 10))
 		if(on_generate_callback)
 			on_generate_callback.Invoke(reagents.total_volume, reagents.maximum_volume)