Supports the ability for commands to be registered internally (#12520)

paper-api/src/main/java/io/papermc/paper/command/brigadier/CommandRegistrationFlag.java

@@ -15,5 +15,9 @@ public enum CommandRegistrationFlag {
      * @deprecated This is the default behavior now.
      */
     @Deprecated(since = "1.21.4")
-    FLATTEN_ALIASES
+    FLATTEN_ALIASES,
+    /**
+     * Prevents this command from being sent to the client.
+     */
+    SERVER_ONLY
 }

paper-server/patches/sources/com/mojang/brigadier/tree/CommandNode.java.patch

@@ -13,7 +13,7 @@
 +    public CommandNode<net.minecraft.commands.CommandSourceStack> clientNode; // Paper - Brigadier API
 +    public CommandNode<io.papermc.paper.command.brigadier.CommandSourceStack> unwrappedCached = null; // Paper - Brigadier Command API
 +    public CommandNode<io.papermc.paper.command.brigadier.CommandSourceStack> wrappedCached = null; // Paper - Brigadier Command API
-+    public io.papermc.paper.command.brigadier.PluginCommandMeta pluginCommandMeta; // Paper - Brigadier Command API
++    public io.papermc.paper.command.brigadier.APICommandMeta apiCommandMeta; // Paper - Brigadier Command API
 +    // CraftBukkit start
 +    public void removeCommand(String name) {
 +        this.children.remove(name);

paper-server/patches/sources/net/minecraft/commands/Commands.java.patch

@@ -172,7 +172,7 @@
              }
  
              return null;
-@@ -359,26 +_,120 @@
+@@ -359,26 +_,121 @@
      }
  
      public void sendCommands(ServerPlayer player) {
@@ -252,6 +252,7 @@
 +            }
 +            // Paper end - Brigadier API
 +            if (!org.spigotmc.SpigotConfig.sendNamespaced && commandNode.getName().contains(":")) continue; // Spigot
++            if (commandNode.wrappedCached != null && commandNode.wrappedCached.apiCommandMeta != null && commandNode.wrappedCached.apiCommandMeta.serverSideOnly()) continue; // Paper
              if (commandNode.canUse(source)) {
                  ArgumentBuilder<SharedSuggestionProvider, ?> argumentBuilder = (ArgumentBuilder) commandNode.createBuilder();
 +                // Paper start

paper-server/patches/sources/net/minecraft/server/ReloadableServerResources.java.patch

@@ -1,12 +1,13 @@
 --- a/net/minecraft/server/ReloadableServerResources.java
 +++ b/net/minecraft/server/ReloadableServerResources.java
-@@ -38,7 +_,8 @@
+@@ -38,7 +_,9 @@
          this.fullRegistryHolder = new ReloadableServerRegistries.Holder(registryAccess.compositeAccess());
          this.postponedTags = postponedTags;
          this.recipes = new RecipeManager(registries);
 -        this.commands = new Commands(commandSelection, CommandBuildContext.simple(registries, enabledFeatures));
 +        this.commands = new Commands(commandSelection, CommandBuildContext.simple(registries, enabledFeatures), true); // Paper - Brigadier Command API - use modern alias registration
 +        io.papermc.paper.command.brigadier.PaperCommands.INSTANCE.setDispatcher(this.commands, CommandBuildContext.simple(registries, enabledFeatures)); // Paper - Brigadier Command API
++        io.papermc.paper.command.PaperCommands.registerCommands(); // Paper
          this.advancements = new ServerAdvancementManager(registries);
          this.functionLibrary = new ServerFunctionLibrary(functionCompilationLevel, this.commands.getDispatcher());
      }

paper-server/src/main/java/io/papermc/paper/command/PaperCommands.java

@@ -1,10 +1,15 @@
 package io.papermc.paper.command;
 
+import com.mojang.brigadier.tree.LiteralCommandNode;
+import io.papermc.paper.command.brigadier.CommandRegistrationFlag;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
 import net.minecraft.server.MinecraftServer;
 import org.bukkit.command.Command;
 
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.framework.qual.DefaultQualifier;
 
@@ -15,16 +20,31 @@ public final class PaperCommands {
     }
 
     private static final Map<String, Command> COMMANDS = new HashMap<>();
-    static {
+
+    public static void registerCommands(final MinecraftServer server) {
         COMMANDS.put("paper", new PaperCommand("paper"));
         COMMANDS.put("callback", new CallbackCommand("callback"));
         COMMANDS.put("mspt", new MSPTCommand("mspt"));
-    }
 
-    public static void registerCommands(final MinecraftServer server) {
         COMMANDS.forEach((s, command) -> {
             server.server.getCommandMap().register(s, "Paper", command);
         });
         server.server.getCommandMap().register("bukkit", new PaperPluginsCommand());
     }
+
+    public static void registerCommands() {
+         // Paper commands go here
+    }
+
+    private static void registerInternalCommand(final LiteralCommandNode<CommandSourceStack> node, final String description, final List<String> aliases, final Set<CommandRegistrationFlag> flags) {
+        io.papermc.paper.command.brigadier.PaperCommands.INSTANCE.registerWithFlagsInternal(
+            null,
+            "paper",
+            "Paper",
+            node,
+            description,
+            aliases,
+            flags
+        );
+    }
 }

paper-server/src/main/java/io/papermc/paper/command/brigadier/APICommandMeta.java

@@ -0,0 +1,31 @@
+package io.papermc.paper.command.brigadier;
+
+import io.papermc.paper.plugin.configuration.PluginMeta;
+import java.util.Collections;
+import java.util.List;
+import java.util.Objects;
+import org.bukkit.Bukkit;
+import org.bukkit.plugin.Plugin;
+import org.jspecify.annotations.NullMarked;
+import org.jspecify.annotations.Nullable;
+
+@NullMarked
+public record APICommandMeta(@Nullable PluginMeta pluginMeta, @Nullable String description, List<String> aliases, @Nullable String helpCommandNamespace, boolean serverSideOnly) {
+
+    public APICommandMeta(final @Nullable PluginMeta pluginMeta, final @Nullable String description) {
+        this(pluginMeta, description, Collections.emptyList(), null, false);
+    }
+
+    public APICommandMeta {
+        aliases = List.copyOf(aliases);
+    }
+
+    @Nullable
+    public Plugin plugin() {
+        return this.pluginMeta == null ? null : Objects.requireNonNull(Bukkit.getPluginManager().getPlugin(this.pluginMeta.getName()));
+    }
+
+    public APICommandMeta withAliases(List<String> registeredAliases) {
+        return new APICommandMeta(this.pluginMeta, this.description, List.copyOf(registeredAliases), this.helpCommandNamespace, this.serverSideOnly);
+    }
+}

paper-server/src/main/java/io/papermc/paper/command/brigadier/PaperBrigadier.java

@@ -35,8 +35,8 @@ public final class PaperBrigadier {
             throw new IllegalArgumentException("Unsure how to wrap a " + node);
         }
 
-        final PluginCommandMeta meta;
-        if ((meta = node.pluginCommandMeta) == null) {
+        final APICommandMeta meta;
+        if ((meta = node.apiCommandMeta) == null) {
             return new VanillaCommandWrapper(node);
         }
         CommandNode<CommandSourceStack> argumentCommandNode = node;
@@ -46,6 +46,12 @@ public final class PaperBrigadier {
 
         Map<CommandNode<CommandSourceStack>, String> map = PaperCommands.INSTANCE.getDispatcherInternal().getSmartUsage(argumentCommandNode, DUMMY);
         String usage = map.isEmpty() ? node.getUsageText() :  node.getUsageText() + " " + String.join("\n" + node.getUsageText() + " ", map.values());
+
+        // Internal command
+        if (meta.pluginMeta() == null) {
+            return new VanillaCommandWrapper(node.getName(), meta.description(), usage, meta.aliases(), node, meta.helpCommandNamespace());
+        }
+
         return new PluginVanillaCommandWrapper(node.getName(), meta.description(), usage, meta.aliases(), node, meta.plugin());
     }
 

paper-server/src/main/java/io/papermc/paper/command/brigadier/PaperCommands.java

@@ -91,10 +91,13 @@ public class PaperCommands implements Commands, PaperRegistrar<LifecycleEventOwn
 
     @Override
     public @Unmodifiable Set<String> registerWithFlags(final PluginMeta pluginMeta, final LiteralCommandNode<CommandSourceStack> node, final @Nullable String description, final Collection<String> aliases, final Set<CommandRegistrationFlag> flags) {
-        final PluginCommandMeta meta = new PluginCommandMeta(pluginMeta, description);
-        final String identifier = pluginMeta.getName().toLowerCase(Locale.ROOT);
+        return registerWithFlagsInternal(pluginMeta, pluginMeta.getName().toLowerCase(Locale.ROOT), null, node, description, aliases, flags);
+    }
+
+    public @Unmodifiable Set<String> registerWithFlagsInternal(final @Nullable PluginMeta pluginMeta, final String namespace, final @Nullable String helpNamespaceOverride, final LiteralCommandNode<CommandSourceStack> node, final @Nullable String description, final Collection<String> aliases, final Set<CommandRegistrationFlag> flags) {
+        final APICommandMeta meta = new APICommandMeta(pluginMeta, description, List.of(), helpNamespaceOverride, flags.contains(CommandRegistrationFlag.SERVER_ONLY));
         final String literal = node.getLiteral();
-        final LiteralCommandNode<CommandSourceStack> pluginLiteral = PaperBrigadier.copyLiteral(identifier + ":" + literal, node);
+        final LiteralCommandNode<CommandSourceStack> pluginLiteral = PaperBrigadier.copyLiteral(namespace + ":" + literal, node);
 
         final Set<String> registeredLabels = new HashSet<>(aliases.size() * 2 + 2);
 
@@ -111,27 +114,27 @@ public class PaperCommands implements Commands, PaperRegistrar<LifecycleEventOwn
             if (this.registerCopy(alias, pluginLiteral, meta)) {
                 registeredAliases.add(alias);
             }
-            if (this.registerCopy(identifier + ":" + alias, pluginLiteral, meta)) {
-                registeredAliases.add(identifier + ":" + alias);
+            if (this.registerCopy(namespace + ":" + alias, pluginLiteral, meta)) {
+                registeredAliases.add(namespace + ":" + alias);
             }
         }
 
-        pluginLiteral.pluginCommandMeta = new PluginCommandMeta(pluginMeta, description, registeredAliases);
-        node.pluginCommandMeta = pluginLiteral.pluginCommandMeta;
+        pluginLiteral.apiCommandMeta = meta.withAliases(registeredAliases);
+        node.apiCommandMeta = pluginLiteral.apiCommandMeta;
 
         registeredLabels.addAll(registeredAliases);
         return registeredLabels.isEmpty() ? Collections.emptySet() : Collections.unmodifiableSet(registeredLabels);
     }
 
-    private boolean registerCopy(final String aliasLiteral, final LiteralCommandNode<CommandSourceStack> redirectTo, final PluginCommandMeta meta) {
+    private boolean registerCopy(final String aliasLiteral, final LiteralCommandNode<CommandSourceStack> redirectTo, final APICommandMeta meta) {
         final LiteralCommandNode<CommandSourceStack> node = PaperBrigadier.copyLiteral(aliasLiteral, redirectTo);
-        node.pluginCommandMeta = meta;
+        node.apiCommandMeta = meta;
         return this.registerIntoDispatcher(node, false);
     }
 
     private boolean registerIntoDispatcher(final LiteralCommandNode<CommandSourceStack> node, boolean override) {
         final CommandNode<CommandSourceStack> existingChild = this.getDispatcher().getRoot().getChild(node.getLiteral());
-        if (existingChild != null && existingChild.pluginCommandMeta == null && !(existingChild instanceof BukkitCommandNode)) {
+        if (existingChild != null && existingChild.apiCommandMeta == null && !(existingChild instanceof BukkitCommandNode)) {
             override = true; // override vanilla commands
         }
         if (existingChild == null || override) { // Avoid merging behavior. Maybe something to look into in the future

paper-server/src/main/java/io/papermc/paper/command/brigadier/PluginCommandMeta.java

@@ -1,26 +0,0 @@
-package io.papermc.paper.command.brigadier;
-
-import io.papermc.paper.plugin.configuration.PluginMeta;
-import java.util.Collections;
-import java.util.List;
-import java.util.Objects;
-import org.bukkit.Bukkit;
-import org.bukkit.plugin.Plugin;
-import org.jspecify.annotations.NullMarked;
-import org.jspecify.annotations.Nullable;
-
-@NullMarked
-public record PluginCommandMeta(PluginMeta pluginMeta, @Nullable String description, List<String> aliases) {
-
-    public PluginCommandMeta(final PluginMeta pluginMeta, final @Nullable String description) {
-        this(pluginMeta, description, Collections.emptyList());
-    }
-
-    public PluginCommandMeta {
-        aliases = List.copyOf(aliases);
-    }
-
-    public Plugin plugin() {
-        return Objects.requireNonNull(Bukkit.getPluginManager().getPlugin(this.pluginMeta.getName()));
-    }
-}

paper-server/src/main/java/io/papermc/paper/command/brigadier/PluginVanillaCommandWrapper.java

@@ -17,7 +17,7 @@ public class PluginVanillaCommandWrapper extends VanillaCommandWrapper implement
     private final List<String> aliases;
 
     public PluginVanillaCommandWrapper(String name, String description, String usageMessage, List<String> aliases, CommandNode<CommandSourceStack> vanillaCommand, Plugin plugin) {
-        super(name, description, usageMessage, aliases, vanillaCommand);
+        super(name, description, usageMessage, aliases, vanillaCommand, null);
         this.plugin = plugin;
         this.aliases = aliases;
     }

paper-server/src/main/java/org/bukkit/craftbukkit/command/VanillaCommandWrapper.java

@@ -26,10 +26,12 @@ import org.bukkit.entity.minecart.CommandMinecart;
 public class VanillaCommandWrapper extends BukkitCommand { // Paper
 
     public final CommandNode<CommandSourceStack> vanillaCommand;
+    public final String helpCommandNamespace;
 
-    public VanillaCommandWrapper(String name, String description, String usageMessage, List<String> aliases, CommandNode<CommandSourceStack> vanillaCommand) {
+    public VanillaCommandWrapper(String name, String description, String usageMessage, List<String> aliases, CommandNode<CommandSourceStack> vanillaCommand, String helpCommandNamespace) {
         super(name, description, usageMessage, aliases);
         this.vanillaCommand = vanillaCommand;
+        this.helpCommandNamespace = helpCommandNamespace;
     }
 
     Commands commands() {
@@ -40,6 +42,7 @@ public class VanillaCommandWrapper extends BukkitCommand { // Paper
         super(vanillaCommand.getName(), "A Mojang provided command.", vanillaCommand.getUsageText(), Collections.emptyList());
         this.vanillaCommand = vanillaCommand;
         this.setPermission(VanillaCommandWrapper.getPermission(vanillaCommand));
+        this.helpCommandNamespace = "Minecraft";
     }
 
     @Override

paper-server/src/main/java/org/bukkit/craftbukkit/help/SimpleHelpMap.java

@@ -199,18 +199,15 @@ public class SimpleHelpMap implements HelpMap {
     }
 
     private String getCommandPluginName(Command command) {
-        // Paper start - Move up
         if (command instanceof PluginIdentifiableCommand) {
             return ((PluginIdentifiableCommand) command).getPlugin().getName();
         }
-        // Paper end
-        if (command instanceof VanillaCommandWrapper) {
-            return "Minecraft";
+        if (command instanceof VanillaCommandWrapper wrapper) {
+            return wrapper.helpCommandNamespace;
         }
         if (command instanceof BukkitCommand) {
             return "Bukkit";
         }
-        // Paper - Move PluginIdentifiableCommand instanceof check to allow brig commands
         return null;
     }