fixes canisters not closing valve on eject (#6028)

code/modules/atmospherics/machinery/portable/canister.dm

@@ -425,18 +425,13 @@ update_flag
 					log_open()
 			valve_open = !valve_open
 			. = TRUE
-		if("eject")
-			if(holding)
-				if(valve_open)
-					valve_open = 0
-					release_log += "Valve was <b>closed</b> by [usr] ([usr.ckey]), stopping the transfer into the [holding]<br>"
-				if(istype(holding, /obj/item/tank))
-					holding.manipulated_by = usr.real_name
-				holding.loc = loc
-				holding = null
-			. = TRUE
 	update_appearance()
 
+/obj/machinery/portable_atmospherics/canister/on_eject(obj/item/tank/tank, mob/user)
+	user.action_feedback(SPAN_WARNING("[src]'s valve closes automatically as you yank \the [tank] out. That was close."), src)
+	valve_open = FALSE
+	return ..()
+
 /obj/machinery/portable_atmospherics/canister/phoron/Initialize(mapload)
 	. = ..()
 	src.air_contents.adjust_gas(GAS_ID_PHORON, MolesForPressure())

code/modules/atmospherics/machinery/portable/portable_atmospherics.dm

@@ -123,11 +123,18 @@
 		if("eject")
 			if(isnull(holding))
 				return TRUE
+			on_eject(holding, usr)
 			usr.action_feedback(SPAN_NOTICE("You remove [holding] from [src]."), src)
 			usr.grab_item_from_interacted_with(holding, src)
 			holding = null
 			return TRUE
 
+/**
+ * Called on tank ejection
+ */
+/obj/machinery/portable_atmospherics/proc/on_eject(obj/item/tank/tank, mob/user)
+	return TRUE
+
 /obj/machinery/portable_atmospherics/proc/set_on(enabled)
 	on = enabled
 	update_icon()