From b5f3b89d8a9433849ee044925f2b0ffc583ba738 Mon Sep 17 00:00:00 2001
From: LemonInTheDark <58055496+LemonInTheDark@users.noreply.github.com>
Date: Sun, 14 Jun 2026 13:27:28 -0700
Subject: [PATCH] Fixes rotation breaking on one votable map (#96493)

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## About The Pull Request

Basically, if it's forced, we rely on create_vote to catch the "no
options" case.
This used to be the behavior, but it was removed in persistant tallies.
I have no idea why.
I've also cleaned up the quite dubious caching code to avoid the bugs I
was getting when testing locally.

## Why It's Good For The Game

S been causing forced icebox (15 pop min, meta can't replace it because
meta's the only one with 0 minpop) on the servers, that's silly.

Of note, it's possible this will still be an issue due to the stale map
system, but yaknow, one thing at a time, and that'll be louder so we
should find out pretty fast (fix would be defaulting to some marked
default map if only one can be rolled).

## Changelog

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:cl:
fix: End of round mapvotes will now properly default to the only option
if only one map is votable.
/:cl:

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---
 code/controllers/subsystem/map_vote.dm |  9 +++++++--
 code/datums/votes/map_vote.dm          | 14 ++++++++------
 2 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/code/controllers/subsystem/map_vote.dm b/code/controllers/subsystem/map_vote.dm
index 4229ee82737..6f0f3a501da 100644
--- a/code/controllers/subsystem/map_vote.dm
+++ b/code/controllers/subsystem/map_vote.dm
@@ -22,6 +22,9 @@ SUBSYSTEM_DEF(map_vote)
 	/// Stores the last amount of potential players to compare next time we're called
 	var/player_cache = -1
 
+	/// Cached list of votable maps
+	var/list/votable_map_cache
+
 	/// Stores a formatted html string of the tally counts
 	var/tally_printout = span_red("Loading...")
 
@@ -113,8 +116,9 @@ SUBSYSTEM_DEF(map_vote)
 	else
 		filter_threshold = length(GLOB.clients)
 
-	if(filter_threshold == player_cache)
-		return null
+	// Cached because it's called off ui_data, I really don't think this is worth it but whatever
+	if(filter_threshold == player_cache && !isnull(votable_map_cache))
+		return votable_map_cache.Copy()
 
 	player_cache = filter_threshold
 	var/list/valid_maps = list()
@@ -130,6 +134,7 @@ SUBSYSTEM_DEF(map_vote)
 			continue
 		valid_maps += possible_config.map_name
 
+	votable_map_cache = valid_maps.Copy()
 	return valid_maps
 
 /datum/controller/subsystem/map_vote/proc/filter_cache_to_valid_maps()
diff --git a/code/datums/votes/map_vote.dm b/code/datums/votes/map_vote.dm
index 08f792d291d..dd099919aeb 100644
--- a/code/datums/votes/map_vote.dm
+++ b/code/datums/votes/map_vote.dm
@@ -4,14 +4,13 @@
 	count_method = VOTE_COUNT_METHOD_SINGLE
 	winner_method = VOTE_WINNER_METHOD_NONE
 	display_statistics = FALSE
+
 /datum/vote/map_vote/New()
 	. = ..()
 	default_choices = SSmap_vote.get_valid_map_vote_choices()
 
 /datum/vote/map_vote/create_vote()
-	var/list/new_choices = SSmap_vote.get_valid_map_vote_choices()
-	if (new_choices)
-		default_choices = new_choices
+	default_choices = SSmap_vote.get_valid_map_vote_choices()
 	. = ..()
 	if(!.)
 		return FALSE
@@ -43,10 +42,13 @@
 	if(SSmap_vote.next_map_config)
 		return "The next map has already been selected."
 
+	// The below case will be caught in create_vote() if the vote is being forced
+	// This ensures proper map rotation if there aren't enough votable maps for whatever reason
+	if(forced)
+		return VOTE_AVAILABLE
+
 	var/list/new_choices = SSmap_vote.get_valid_map_vote_choices()
-	if (new_choices)
-		default_choices = new_choices
-	var/num_choices = length(default_choices)
+	var/num_choices = length(new_choices)
 	if(num_choices <= 1)
 		return "There [num_choices == 1 ? "is only one map" : "are no maps"] to choose from."