From 0c1a21f6ae6bcf48cbb4582a76976857febef198 Mon Sep 17 00:00:00 2001
From: Xander Lenstra <71121390+xlenstra@users.noreply.github.com>
Date: Sat, 7 Aug 2021 22:44:16 +0200
Subject: [PATCH] Fixed crash when borrowing names (#4800)

* Fixed crash when borrowing names

* Fix potential mod error allowed by the previous fix
---
 core/src/com/unciv/models/ruleset/Nation.kt  | 2 +-
 core/src/com/unciv/models/ruleset/Ruleset.kt | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/core/src/com/unciv/models/ruleset/Nation.kt b/core/src/com/unciv/models/ruleset/Nation.kt
index b5a253fd82..df664c9ce4 100644
--- a/core/src/com/unciv/models/ruleset/Nation.kt
+++ b/core/src/com/unciv/models/ruleset/Nation.kt
@@ -94,7 +94,7 @@ class Nation : INamed, ICivilopediaText {
         disembarkCosts1 = uniques.contains("Units pay only 1 movement point to disembark")
     }
 
-    lateinit var cities: ArrayList<String>
+    var cities: ArrayList<String> = arrayListOf()
 
 
     /** Used only by NewGame Nation picker */
diff --git a/core/src/com/unciv/models/ruleset/Ruleset.kt b/core/src/com/unciv/models/ruleset/Ruleset.kt
index 37a72a7693..558508e2be 100644
--- a/core/src/com/unciv/models/ruleset/Ruleset.kt
+++ b/core/src/com/unciv/models/ruleset/Ruleset.kt
@@ -307,6 +307,12 @@ class Ruleset {
             if (building.requiredTech == null && building.cost == 0)
                 lines += "${building.name} must either have an explicit cost or reference an existing tech!"
         }
+        
+        for (nation in nations.values) {
+            if (nation.cities.isEmpty() && !nation.isSpectator() && !nation.isBarbarian()) {
+                lines += "${nation.name} can settle cities, but has no city names!"
+            }
+        }
 
         if (!modOptions.isBaseRuleset) return CheckModLinksResult(warningCount, lines)