From 2a21cc0e0e438f74c2e58c21e3795061a1dd17bd Mon Sep 17 00:00:00 2001
From: Zach Brown <zach@zachbr.io>
Date: Thu, 6 Feb 2020 19:20:27 -0600
Subject: [PATCH] Be more tolerant of invalid attributes

Prior to this commit, the player would be disconnected if they ever encountered an attribute with a name that did
not match Bukkit's expected vanilla scheme. It appears that datapacks can set whatever attribute name they want,
ignoring vanilla's typical scheme.

In a more perfect world the API would expose some way to interact with these attributes, however Bukkit is not
particularly flexible in this area. Perhaps this is an area for future expansion at a later time.

diff --git a/src/main/java/org/bukkit/craftbukkit/attribute/CraftAttributeMap.java b/src/main/java/org/bukkit/craftbukkit/attribute/CraftAttributeMap.java
index 77e584b129..007d28b16c 100644
--- a/src/main/java/org/bukkit/craftbukkit/attribute/CraftAttributeMap.java
+++ b/src/main/java/org/bukkit/craftbukkit/attribute/CraftAttributeMap.java
@@ -47,6 +47,12 @@ public class CraftAttributeMap implements Attributable {
     public static Attribute fromMinecraft(String nms) {
         String[] split = nms.split("\\.", 2);
 
+        // Paper start - Datapacks can set their own attributes that may not match our expectations, ignore them
+        if (split.length != 2) {
+            return null;
+        }
+        // Paper end
+
         String generic = split[0];
         String descriptor = CaseFormat.LOWER_CAMEL.to(CaseFormat.UPPER_UNDERSCORE, split[1]); // movementSpeed -> MOVEMENT_SPEED
         String fin = generic + "_" + descriptor;
-- 
2.26.2