fixing a bunch of unit test/runtime issues

code/game/objects/effects/decals/cleanable/humans.dm

@@ -53,7 +53,7 @@
 	bloodiness = 0
 
 /obj/effect/decal/cleanable/blood/old/Initialize(mapload, list/datum/disease/diseases)
-	..()
+	. = ..()
 	icon_state += "-old"
 	add_blood_DNA(list("Non-human DNA" = "A+"))
 

code/game/objects/items/manuals.dm

@@ -337,7 +337,7 @@
 	page_link = "Guide_to_chemistry"
 
 /obj/item/book/manual/wiki/chemistry/Initialize()
-	..()
+	. = ..()
 	new /obj/item/book/manual/wiki/cit/chemistry(loc)
 	new /obj/item/book/manual/wiki/cit/chem_recipies(loc)
 

code/game/objects/items/plushes.dm

@@ -466,7 +466,7 @@ GLOBAL_LIST_INIT(valid_plushie_paths, valid_plushie_paths())
 	can_random_spawn = FALSE
 
 /obj/item/toy/plush/random/Initialize()
-	SHOULD_CALL_PARENT(FALSE)
+	..()
 	var/newtype
 	var/list/snowflake_list = CONFIG_GET(keyed_list/snowflake_plushies)
 

code/game/objects/items/stacks/stack.dm

@@ -48,7 +48,7 @@
 		amount -= max_amount
 		new type(loc, max_amount, FALSE)
 	if(!merge_type)
-		merge_type = type
+		merge_type = src.type
 
 	if(LAZYLEN(mats_per_unit))
 		set_mats_per_unit(mats_per_unit, 1)