Adds a bunch of owner.current nullchecks to antag code (#91524)

This could cause runtimes preventing antag datum removal in case your
body got destroyed. Ideally we'd unit test for this, but I can't get it
to work sanely without touching some dynamic code (due to some antag
datums requiring a bunch of snowflaky setups), so the unit test will
come after its refactored.

🆑
fix: Fixed some edge cases where antagonist datums would "stick" and not
get removed if your body got destroyed.
/🆑

---------

Co-authored-by: Ghom <42542238+Ghommie@users.noreply.github.com>

code/datums/mind/antag.dm

@@ -34,14 +34,14 @@
 	var/datum/antagonist/A = has_antag_datum(datum_type)
 	if(A)
 		A.on_removal()
-		current.log_message("has lost antag datum [A.name]([A.type]).", LOG_GAME)
+		current?.log_message("has lost antag datum [A.name]([A.type]).", LOG_GAME)
 		return TRUE
 
 /datum/mind/proc/remove_all_antag_datums() //For the Lazy amongst us.
 	for(var/a in antag_datums)
 		var/datum/antagonist/A = a
 		A.on_removal()
-	current.log_message("has lost all antag datums.", LOG_GAME)
+	current?.log_message("has lost all antag datums.", LOG_GAME)
 
 /datum/mind/proc/has_antag_datum(datum_type, check_subtypes = TRUE)
 	if(!datum_type)
@@ -93,6 +93,8 @@
 
 
 /datum/mind/proc/remove_antag_equip()
+	if(!current)
+		return
 	var/list/Mob_Contents = current.get_contents()
 	for(var/obj/item/I in Mob_Contents)
 		var/datum/component/uplink/O = I.GetComponent(/datum/component/uplink) //Todo make this reset signal

code/modules/antagonists/_common/antag_datum.dm

@@ -194,7 +194,8 @@ GLOBAL_LIST_EMPTY(antagonists)
 ///Called by the transfer_to() mind proc after the mind (mind.current and new_character.mind) has moved but before the player (key and client) is transferred.
 /datum/antagonist/proc/on_body_transfer(mob/living/old_body, mob/living/new_body)
 	SHOULD_CALL_PARENT(TRUE)
-	remove_innate_effects(old_body)
+	if(old_body)
+		remove_innate_effects(old_body)
 	if(old_body && old_body.stat != DEAD && !LAZYLEN(old_body.mind?.antag_datums))
 		old_body.remove_from_current_living_antags()
 	var/datum/action/antag_info/info_button = info_button_ref?.resolve()
@@ -318,10 +319,11 @@ GLOBAL_LIST_EMPTY(antagonists)
 	if(!owner)
 		CRASH("Antag datum with no owner.")
 
-	remove_innate_effects()
+	if(owner.current)
+		remove_innate_effects()
 	clear_antag_moodies()
 	LAZYREMOVE(owner.antag_datums, src)
-	if(!LAZYLEN(owner.antag_datums))
+	if(!LAZYLEN(owner.antag_datums) && owner.current)
 		owner.current.remove_from_current_living_antags()
 	if(info_button_ref)
 		QDEL_NULL(info_button_ref)
@@ -362,7 +364,7 @@ GLOBAL_LIST_EMPTY(antagonists)
  * Use this proc for playing sounds, sending alerts, or otherwise informing the player that they're no longer a specific antagonist type.
  */
 /datum/antagonist/proc/farewell()
-	if(!silent)
+	if(!silent && owner.current)
 		to_chat(owner.current, span_userdanger("You are no longer \the [src]!"))
 
 /**

code/modules/antagonists/ashwalker/ashwalker.dm

@@ -34,6 +34,8 @@
 
 /datum/antagonist/ashwalker/on_removal()
 	. = ..()
+	if(!owner.current)
+		return
 	UnregisterSignal(owner.current, COMSIG_MOB_EXAMINATE)
 	if(!(FACTION_NEUTRAL in owner.current.faction))
 		owner.current.faction.Add(FACTION_NEUTRAL)

code/modules/antagonists/changeling/changeling.dm

@@ -242,7 +242,8 @@
 	return ..()
 
 /datum/antagonist/changeling/farewell()
-	to_chat(owner.current, span_userdanger("You grow weak and lose your powers! You are no longer a changeling and are stuck in your current form!"))
+	if(owner.current)
+		to_chat(owner.current, span_userdanger("You grow weak and lose your powers! You are no longer a changeling and are stuck in your current form!"))
 
 /*
  * Instantiate the cellular emporium for the changeling.

code/modules/antagonists/clown_ops/clownop.dm

@@ -24,7 +24,6 @@
 /datum/antagonist/nukeop/clownop/remove_innate_effects(mob/living/mob_override)
 	var/mob/living/L = owner.current || mob_override
 	REMOVE_TRAIT(L.mind, TRAIT_NAIVE, CLOWNOP_TRAIT)
-	return ..()
 
 /datum/antagonist/nukeop/clownop/equip_op()
 	. = ..()
@@ -56,7 +55,6 @@
 /datum/antagonist/nukeop/leader/clownop/remove_innate_effects(mob/living/mob_override)
 	var/mob/living/L = owner.current || mob_override
 	REMOVE_TRAIT(L.mind, TRAIT_NAIVE, CLOWNOP_TRAIT)
-	return ..()
 
 /datum/antagonist/nukeop/leader/clownop/equip_op()
 	. = ..()

code/modules/antagonists/cult/datums/cultist.dm

@@ -39,6 +39,9 @@
 	current.log_message("has been converted to the cult of Nar'Sie!", LOG_ATTACK, color=COLOR_CULT_RED)
 
 /datum/antagonist/cult/on_removal()
+	if (!owner.current)
+		return ..()
+
 	if(!silent)
 		owner.current.visible_message(span_deconversion_message("[owner.current] looks like [owner.current.p_theyve()] just reverted to [owner.current.p_their()] old faith!"), ignored_mobs = owner.current)
 		to_chat(owner.current, span_userdanger("An unfamiliar white light flashes through your mind, cleansing the taint of the Geometer and all your memories as her servant."))
@@ -238,7 +241,7 @@
 /datum/antagonist/cult/proc/deathrattle(datum/source)
 	SIGNAL_HANDLER
 
-	if(owner.current.stat != DEAD)
+	if(owner.current?.stat != DEAD)
 		return
 	if(!QDELETED(GLOB.cult_narsie))
 		return

code/modules/antagonists/fugitive/hunters/hunter.dm

@@ -80,10 +80,9 @@
 
 /datum/antagonist/fugitive_hunter/remove_innate_effects(mob/living/mob_override)
 	var/mob/living/owner_mob = mob_override || owner.current
-	//bubber edit; spinwarder removed
+	// BUBBER EDIT CHANGE BEGIN: spinwarder removed
 	owner_mob.remove_language(/datum/language/panslavic, source = LANGUAGE_BOUNTYHUNTER)
-	//edit end
-	return ..()
+	// BUBBER EDIT CHANGE END
 
 /datum/team/fugitive_hunters
 	var/backstory = "error"

code/modules/antagonists/heretic/heretic_antag.dm

@@ -259,7 +259,7 @@
 	return finish_preview_icon(icon)
 
 /datum/antagonist/heretic/farewell()
-	if(!silent)
+	if(!silent && owner.current)
 		to_chat(owner.current, span_userdanger("Your mind begins to flare as the otherwordly knowledge escapes your grasp!"))
 	return ..()
 
@@ -278,9 +278,10 @@
 	return ..()
 
 /datum/antagonist/heretic/on_removal()
-	for(var/knowledge_index in researched_knowledge)
-		var/datum/heretic_knowledge/knowledge = researched_knowledge[knowledge_index]
-		knowledge.on_lose(owner.current, src)
+	if(owner.current)
+		for(var/knowledge_index in researched_knowledge)
+			var/datum/heretic_knowledge/knowledge = researched_knowledge[knowledge_index]
+			knowledge.on_lose(owner.current, src)
 
 	QDEL_LIST_ASSOC_VAL(researched_knowledge)
 	return ..()

code/modules/antagonists/malf_ai/malf_ai.dm

@@ -138,8 +138,6 @@
 	datum_owner.AddComponent(/datum/component/codeword_hearing, GLOB.syndicate_code_response_regex, "red", src)
 
 /datum/antagonist/malf_ai/remove_innate_effects(mob/living/mob_override)
-	. = ..()
-
 	var/mob/living/silicon/ai/datum_owner = mob_override || owner.current
 
 	if(istype(datum_owner))
@@ -270,7 +268,8 @@
 		result += span_greentext("The [special_role_text] was successful!")
 	else
 		result += span_redtext("The [special_role_text] has failed!")
-		SEND_SOUND(owner.current, 'sound/ambience/misc/ambifailure.ogg')
+		if(owner.current)
+			SEND_SOUND(owner.current, 'sound/ambience/misc/ambifailure.ogg')
 
 	return result.Join("<br>")
 
@@ -288,7 +287,7 @@
 	SIGNAL_HANDLER
 
 	var/mob/living/silicon/ai/malf_owner = owner.current
-	if(malf_owner.linked_core)
+	if(malf_owner?.linked_core)
 		return COMPONENT_CORE_ALL_GOOD
 	return COMPONENT_CORE_DISCONNECTED
 

code/modules/antagonists/nightmare/nightmare.dm

@@ -39,7 +39,7 @@
 	..()
 
 /datum/objective/nightmare_fluff/check_completion()
-	return owner.current.stat != DEAD
+	return owner.current && owner.current.stat != DEAD
 
 /datum/antagonist/nightmare/forge_objectives()
 	var/datum/objective/nightmare_fluff/objective = new

code/modules/antagonists/pirate/pirate.dm

@@ -48,8 +48,8 @@
 
 /datum/antagonist/pirate/remove_innate_effects(mob/living/mob_override)
 	var/mob/living/owner_mob = mob_override || owner.current
-	owner_mob.remove_language(/datum/language/piratespeak, source = LANGUAGE_PIRATE)
-	return ..()
+	if (owner_mob)
+		owner_mob.remove_language(/datum/language/piratespeak, source = LANGUAGE_PIRATE)
 
 /datum/team/pirate
 	name = "\improper Pirate crew"

code/modules/antagonists/pyro_slime/pyro_slime.dm

@@ -18,7 +18,7 @@
 	explanation_text = "I am fire. I am hunger. The cold is agony. The living pulse with energy; their warmth fuels me. The dead are husks, their embers long faded. Water is death. Fire... fire is freedom."
 
 /datum/objective/pyro_slime/check_completion()
-	return owner.current.stat != DEAD
+	return owner.current && owner.current.stat != DEAD
 
 /datum/antagonist/pyro_slime/forge_objectives()
 	var/datum/objective/pyro_slime/objective = new

code/modules/antagonists/revolution/revolution.dm

@@ -184,11 +184,14 @@
 	return COMPONENT_MINDSHIELD_RESISTED
 
 /datum/antagonist/rev/head/on_removal()
-	if(give_hud)
-		var/mob/living/carbon/C = owner.current
-		var/obj/item/organ/cyberimp/eyes/hud/security/syndicate/S = C.get_organ_slot(ORGAN_SLOT_HUD)
-		if(S)
-			S.Remove(C)
+	if(!give_hud)
+		return ..()
+	var/mob/living/carbon/C = owner.current
+	if (!C)
+		return ..()
+	var/obj/item/organ/cyberimp/eyes/hud/security/syndicate/S = C.get_organ_slot(ORGAN_SLOT_HUD)
+	if(S)
+		S.Remove(C)
 	return ..()
 
 /datum/antagonist/rev/head/apply_innate_effects(mob/living/mob_override)
@@ -310,6 +313,8 @@
 	to_chat(old_owner, span_userdanger("Revolution has been disappointed of your leader traits! You are a regular revolutionary now!"))
 
 /datum/antagonist/rev/farewell()
+	if(!owner.current)
+		return
 	owner.current.balloon_alert_to_viewers("deconverted!")
 	if(ishuman(owner.current))
 		owner.current.visible_message(span_deconversion_message("[owner.current] looks like [owner.current.p_theyve()] just remembered [owner.current.p_their()] real allegiance!"), null, null, null, owner.current)
@@ -319,7 +324,7 @@
 		to_chat(owner, span_userdanger("The frame's firmware detects and deletes your neural reprogramming! You remember nothing but the name of the one who flashed you."))
 
 /datum/antagonist/rev/head/farewell()
-	if (deconversion_source == DECONVERTER_STATION_WIN)
+	if (deconversion_source == DECONVERTER_STATION_WIN || !owner.current)
 		return
 	owner.current.balloon_alert_to_viewers("deconverted!")
 	if((ishuman(owner.current)))

code/modules/antagonists/spiders/spiders.dm

@@ -29,7 +29,7 @@
 		explanation_text = "Your queen has given you a directive! Follow it at all costs: [directive]"
 
 /datum/objective/spider/check_completion()
-	return owner.current.stat != DEAD
+	return owner.current && owner.current.stat != DEAD
 
 /datum/antagonist/spider/forge_objectives()
 	var/datum/objective/spider/objective = new(directive)

code/modules/antagonists/syndicate_monkey/syndicate_monkey.dm

@@ -27,7 +27,7 @@
 	var/mob/living/monky_master
 
 /datum/objective/syndicate_monkey/check_completion()
-	return monky_master.stat != DEAD
+	return monky_master && monky_master.stat != DEAD
 
 /datum/antagonist/syndicate_monkey/forge_objectives(mob/monky_master)
 	var/datum/objective/syndicate_monkey/objective = new

code/modules/antagonists/traitor/datum_traitor.dm

@@ -209,7 +209,6 @@
 		datum_owner.AddComponent(/datum/component/codeword_hearing, GLOB.syndicate_code_response_regex, "red", src)
 
 /datum/antagonist/traitor/remove_innate_effects(mob/living/mob_override)
-	. = ..()
 	var/mob/living/datum_owner = mob_override || owner.current
 	handle_clown_mutation(datum_owner, removing = FALSE)
 

code/modules/antagonists/venus_human_trap/venus_human_trap.dm

@@ -18,7 +18,7 @@
 	explanation_text = "Spread the infestation."
 
 /datum/objective/venus_human_trap/check_completion()
-	return owner.current.stat != DEAD
+	return owner.current && owner.current.stat != DEAD
 
 /datum/antagonist/venus_human_trap/forge_objectives()
 	var/datum/objective/venus_human_trap/objective = new

code/modules/antagonists/voidwalker/voidwalker.dm

@@ -57,4 +57,4 @@
 	..()
 
 /datum/objective/voidwalker_objective/check_completion()
-	return owner.current.stat != DEAD
+	return owner.current && owner.current.stat != DEAD

code/modules/antagonists/xeno/xeno.dm

@@ -96,7 +96,7 @@
 	explanation_text = "Survive and advance the Hive."
 
 /datum/objective/advance_hive/check_completion()
-	return owner.current.stat != DEAD
+	return owner.current && owner.current.stat != DEAD
 
 ///Captive Xenomorphs team
 /datum/team/xeno/captive