SPIGOT-7496: Failure to load datapacks with multiple identical predicates

By: md_5 <git@md-5.net>

paper-server/nms-patches/net/minecraft/world/level/storage/loot/LootDataManager.patch

@@ -1,14 +1,15 @@
 --- a/net/minecraft/world/level/storage/loot/LootDataManager.java
 +++ b/net/minecraft/world/level/storage/loot/LootDataManager.java
-@@ -30,6 +30,7 @@
+@@ -21,6 +21,8 @@
-     public static final LootDataId<LootTable> EMPTY_LOOT_TABLE_KEY = new LootDataId<>(LootDataType.TABLE, LootTables.EMPTY);
+ import net.minecraft.server.packs.resources.ResourceDataJson;
-     private Map<LootDataId<?>, ?> elements = Map.of();
+ import net.minecraft.util.profiling.GameProfilerFiller;
-     private Multimap<LootDataType<?>, MinecraftKey> typeKeys = ImmutableMultimap.of();
+ import net.minecraft.world.level.storage.loot.parameters.LootContextParameterSets;
-+    public Map<?, MinecraftKey> lootTableToKey = ImmutableMap.of(); // CraftBukkit
++import org.bukkit.craftbukkit.CraftLootTable;
++import org.bukkit.craftbukkit.util.CraftNamespacedKey;
+ import org.slf4j.Logger;
  
-     public LootDataManager() {}
+ public class LootDataManager implements IReloadListener, LootDataResolver {
- 
+@@ -87,7 +89,7 @@
-@@ -87,7 +88,7 @@
              @Nullable
              @Override
              public <T> T getElement(LootDataId<T> lootdataid) {
@@ -17,15 +18,19 @@
              }
          });
  
-@@ -99,16 +100,21 @@
+@@ -97,18 +99,25 @@
+         lootcollector.getProblems().forEach((s, s1) -> {
+             LootDataManager.LOGGER.warn("Found loot table element validation problem in {}: {}", s, s1);
          });
++        // CraftBukkit start
++        map1.forEach((key, lootTable) -> {
++            if (object instanceof LootTable table) {
++                table.craftLootTable = new CraftLootTable(CraftNamespacedKey.fromMinecraft(key.location()), table);
++            }
++        });
++        // CraftBukkit end
          this.elements = map1;
          this.typeKeys = com_google_common_collect_immutablemultimap_builder.build();
-+        // CraftBukkit start - build a reversed registry map
-+        ImmutableMap.Builder<Object, MinecraftKey> lootTableToKeyBuilder = ImmutableMap.builder();
-+        this.elements.forEach((key, lootTable) -> lootTableToKeyBuilder.put((Object) lootTable, key.location()));
-+        this.lootTableToKey = lootTableToKeyBuilder.build();
-+        // CraftBukkit end
      }
  
      private static <T> void castAndValidate(LootCollector lootcollector, LootDataId<T> lootdataid, Object object) {

paper-server/nms-patches/net/minecraft/world/level/storage/loot/LootTable.patch

@@ -5,7 +5,7 @@
  import org.slf4j.Logger;
  
 +// CraftBukkit start
-+import java.util.stream.Collectors;
++import org.bukkit.craftbukkit.CraftLootTable;
 +import org.bukkit.craftbukkit.event.CraftEventFactory;
 +import org.bukkit.craftbukkit.inventory.CraftItemStack;
 +import org.bukkit.event.world.LootGenerateEvent;
@@ -14,7 +14,15 @@
  public class LootTable {
  
      private static final Logger LOGGER = LogUtils.getLogger();
-@@ -149,9 +156,22 @@
+@@ -50,6 +57,7 @@
+     private final List<LootSelector> pools;
+     private final List<LootItemFunction> functions;
+     private final BiFunction<ItemStack, LootTableInfo, ItemStack> compositeFunction;
++    public CraftLootTable craftLootTable; // CraftBukkit
+ 
+     LootTable(LootContextParameterSet lootcontextparameterset, Optional<MinecraftKey> optional, List<LootSelector> list, List<LootItemFunction> list1) {
+         this.paramSet = lootcontextparameterset;
+@@ -149,9 +157,22 @@
      }
  
      public void fill(IInventory iinventory, LootParams lootparams, long i) {

paper-server/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java

@@ -1741,11 +1741,9 @@ public class CraftEventFactory {
     public static LootGenerateEvent callLootGenerateEvent(IInventory inventory, LootTable lootTable, LootTableInfo lootInfo, List<ItemStack> loot, boolean plugin) {
         CraftWorld world = lootInfo.getLevel().getWorld();
         Entity entity = lootInfo.getParamOrNull(LootContextParameters.THIS_ENTITY);
-        NamespacedKey key = CraftNamespacedKey.fromMinecraft(world.getHandle().getServer().getLootData().lootTableToKey.get(lootTable));
-        CraftLootTable craftLootTable = new CraftLootTable(key, lootTable);
         List<org.bukkit.inventory.ItemStack> bukkitLoot = loot.stream().map(CraftItemStack::asCraftMirror).collect(Collectors.toCollection(ArrayList::new));
 
-        LootGenerateEvent event = new LootGenerateEvent(world, (entity != null ? entity.getBukkitEntity() : null), inventory.getOwner(), craftLootTable, CraftLootTable.convertContext(lootInfo), bukkitLoot, plugin);
+        LootGenerateEvent event = new LootGenerateEvent(world, (entity != null ? entity.getBukkitEntity() : null), inventory.getOwner(), lootTable.craftLootTable, CraftLootTable.convertContext(lootInfo), bukkitLoot, plugin);
         Bukkit.getPluginManager().callEvent(event);
         return event;
     }