SPIGOT-4166: Fix Tags being corrupted by early access (and not reflecting reloads)

nms-patches/TagRegistry.patch

@@ -0,0 +1,14 @@
+--- a/net/minecraft/server/TagRegistry.java
++++ b/net/minecraft/server/TagRegistry.java
+@@ -38,6 +38,11 @@
+         TagsBlock.a((Tags) this.a);
+         TagsItem.a((Tags) this.b);
+         TagsFluid.a((Tags) this.c);
++        // CraftBukkit start
++        this.a.version++;
++        this.b.version++;
++        this.c.version++;
++        // CraftBukkit end
+     }
+ 
+     public void a(PacketDataSerializer packetdataserializer) {

nms-patches/TagsServer.patch

@@ -0,0 +1,28 @@
+--- a/net/minecraft/server/TagsServer.java
++++ b/net/minecraft/server/TagsServer.java
+@@ -11,6 +11,7 @@
+ public class TagsServer<T> extends Tags<T> {
+ 
+     private final RegistryMaterials<MinecraftKey, T> a;
++    public int version; // CraftBukkit
+ 
+     public TagsServer(RegistryMaterials<MinecraftKey, T> registrymaterials, String s, String s1) {
+         super(registrymaterials::d, registrymaterials::get, s, false, s1);
+@@ -31,7 +32,7 @@
+             while (iterator1.hasNext()) {
+                 Object object = iterator1.next();
+ 
+-                packetdataserializer.d(this.a.a(object));
++                packetdataserializer.d(this.a.a((T) object)); // CraftBukkit - decompile error
+             }
+         }
+ 
+@@ -49,7 +50,7 @@
+                 arraylist.add(this.a.getId(packetdataserializer.g()));
+             }
+ 
+-            this.c().put(minecraftkey, Tag.a.a().a((Collection) arraylist).b(minecraftkey));
++            this.c().put(minecraftkey, (Tag<T>) Tag.a.a().a((Collection) arraylist).b(minecraftkey)); // CraftBukkit - decompile error
+         }
+ 
+     }

src/main/java/org/bukkit/craftbukkit/CraftServer.java

@@ -1749,15 +1749,17 @@ public final class CraftServer implements Server {
     @Override
     @SuppressWarnings("unchecked")
     public <T extends Keyed> org.bukkit.Tag<T> getTag(String registry, NamespacedKey tag, Class<T> clazz) {
+        MinecraftKey key = CraftNamespacedKey.toMinecraft(tag);
+
         switch (registry) {
             case org.bukkit.Tag.REGISTRY_BLOCKS:
                 Preconditions.checkArgument(clazz == org.bukkit.Material.class, "Block namespace must have material type");
 
-                return (org.bukkit.Tag<T>) new CraftBlockTag(console.getTagRegistry().a().b(CraftNamespacedKey.toMinecraft(tag)));
+                return (org.bukkit.Tag<T>) new CraftBlockTag(console.getTagRegistry().a(), key);
             case org.bukkit.Tag.REGISTRY_ITEMS:
                 Preconditions.checkArgument(clazz == org.bukkit.Material.class, "Item namespace must have material type");
 
-                return (org.bukkit.Tag<T>) new CraftItemTag(console.getTagRegistry().b().b(CraftNamespacedKey.toMinecraft(tag)));
+                return (org.bukkit.Tag<T>) new CraftItemTag(console.getTagRegistry().b(), key);
             default:
                 throw new IllegalArgumentException();
         }

src/main/java/org/bukkit/craftbukkit/tag/CraftBlockTag.java

@@ -4,25 +4,24 @@ import java.util.Collections;
 import java.util.Set;
 import java.util.stream.Collectors;
 import net.minecraft.server.Block;
+import net.minecraft.server.MinecraftKey;
+import net.minecraft.server.TagsServer;
 import org.bukkit.Material;
-import org.bukkit.Tag;
 import org.bukkit.craftbukkit.util.CraftMagicNumbers;
 
-public class CraftBlockTag implements Tag<Material> {
+public class CraftBlockTag extends CraftTag<Block, Material> {
 
-    private final net.minecraft.server.Tag<Block> handle;
-
-    public CraftBlockTag(net.minecraft.server.Tag<Block> handle) {
-        this.handle = handle;
+    public CraftBlockTag(TagsServer<Block> registry, MinecraftKey tag) {
+        super(registry, tag);
     }
 
     @Override
     public boolean isTagged(Material item) {
-        return handle.isTagged(CraftMagicNumbers.getBlock(item));
+        return getHandle().isTagged(CraftMagicNumbers.getBlock(item));
     }
 
     @Override
     public Set<Material> getValues() {
-        return Collections.unmodifiableSet(handle.a().stream().map((block) -> CraftMagicNumbers.getMaterial(block)).collect(Collectors.toSet()));
+        return Collections.unmodifiableSet(getHandle().a().stream().map((block) -> CraftMagicNumbers.getMaterial(block)).collect(Collectors.toSet()));
     }
 }

src/main/java/org/bukkit/craftbukkit/tag/CraftItemTag.java

@@ -4,25 +4,24 @@ import java.util.Collections;
 import java.util.Set;
 import java.util.stream.Collectors;
 import net.minecraft.server.Item;
+import net.minecraft.server.MinecraftKey;
+import net.minecraft.server.TagsServer;
 import org.bukkit.Material;
-import org.bukkit.Tag;
 import org.bukkit.craftbukkit.util.CraftMagicNumbers;
 
-public class CraftItemTag implements Tag<Material> {
+public class CraftItemTag extends CraftTag<Item, Material> {
 
-    private final net.minecraft.server.Tag<Item> handle;
-
-    public CraftItemTag(net.minecraft.server.Tag<Item> handle) {
-        this.handle = handle;
+    public CraftItemTag(TagsServer<Item> registry, MinecraftKey tag) {
+        super(registry, tag);
     }
 
     @Override
     public boolean isTagged(Material item) {
-        return handle.isTagged(CraftMagicNumbers.getItem(item));
+        return getHandle().isTagged(CraftMagicNumbers.getItem(item));
     }
 
     @Override
     public Set<Material> getValues() {
-        return Collections.unmodifiableSet(handle.a().stream().map((item) -> CraftMagicNumbers.getMaterial(item)).collect(Collectors.toSet()));
+        return Collections.unmodifiableSet(getHandle().a().stream().map((item) -> CraftMagicNumbers.getMaterial(item)).collect(Collectors.toSet()));
     }
 }

src/main/java/org/bukkit/craftbukkit/tag/CraftTag.java

@@ -0,0 +1,29 @@
+package org.bukkit.craftbukkit.tag;
+
+import net.minecraft.server.MinecraftKey;
+import net.minecraft.server.TagsServer;
+import org.bukkit.Keyed;
+import org.bukkit.Tag;
+
+public abstract class CraftTag<N, B extends Keyed> implements Tag<B> {
+
+    private final net.minecraft.server.TagsServer<N> registry;
+    private final MinecraftKey tag;
+    //
+    private int version = -1;
+    private net.minecraft.server.Tag<N> handle;
+
+    public CraftTag(TagsServer<N> registry, MinecraftKey tag) {
+        this.registry = registry;
+        this.tag = tag;
+    }
+
+    protected net.minecraft.server.Tag<N> getHandle() {
+        if (version != registry.version) {
+            handle = registry.b(tag);
+            version = registry.version;
+        }
+
+        return handle;
+    }
+}