Check sub-command permissions.

This ensures root commands aren't sent to the client/suggested unless
a player has at least one subcommand available to them.

worldedit-core/src/main/java/com/sk89q/worldedit/command/util/PermissionCondition.java

@@ -26,7 +26,7 @@ import org.enginehub.piston.inject.Key;
 
 import java.util.Set;
 
-public final class PermissionCondition implements Command.Condition {
+public class PermissionCondition implements Command.Condition {
 
     private static final Key<Actor> ACTOR_KEY = Key.of(Actor.class);
 

worldedit-core/src/main/java/com/sk89q/worldedit/command/util/SubCommandPermissionCondition.java

@@ -0,0 +1,52 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.command.util;
+
+import org.enginehub.piston.Command;
+import org.enginehub.piston.inject.InjectedValueAccess;
+
+import java.util.Collection;
+import java.util.Optional;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+public class SubCommandPermissionCondition extends PermissionCondition {
+
+    private final Command.Condition aggregate;
+
+    public SubCommandPermissionCondition(Collection<Command> commands) {
+        super(commands.stream().map(Command::getCondition)
+                .map(c -> c.as(PermissionCondition.class))
+                .flatMap(optCon -> optCon.map(permCon -> permCon.getPermissions().stream()).orElse(Stream.empty()))
+                .collect(Collectors.toSet()));
+        this.aggregate = commands.stream().map(Command::getCondition)
+                .map(c -> c.as(PermissionCondition.class))
+                .filter(Optional::isPresent)
+                .map(Optional::get)
+                .map(c -> c.as(Command.Condition.class))
+                .map(Optional::get)
+                .reduce(Command.Condition::or).orElse(Command.Condition.TRUE);
+    }
+
+    @Override
+    public boolean satisfied(InjectedValueAccess context) {
+        return aggregate.satisfied(context);
+    }
+}

worldedit-core/src/main/java/com/sk89q/worldedit/extension/platform/PlatformCommandManager.java

@@ -80,6 +80,7 @@ import com.sk89q.worldedit.command.argument.RegistryConverter;
 import com.sk89q.worldedit.command.argument.VectorConverter;
 import com.sk89q.worldedit.command.argument.ZonedDateTimeConverter;
 import com.sk89q.worldedit.command.util.PermissionCondition;
+import com.sk89q.worldedit.command.util.SubCommandPermissionCondition;
 import com.sk89q.worldedit.entity.Entity;
 import com.sk89q.worldedit.entity.Player;
 import com.sk89q.worldedit.event.platform.CommandEvent;
@@ -266,11 +267,14 @@ public final class PlatformCommandManager {
             );
             additionalConfig.accept(manager);
 
+            final List<Command> subCommands = manager.getAllCommands().collect(Collectors.toList());
             cmd.addPart(SubCommandPart.builder(TranslatableComponent.of("worldedit.argument.action"),
                 TextComponent.of("Sub-command to run."))
-                .withCommands(manager.getAllCommands().collect(Collectors.toList()))
+                .withCommands(subCommands)
                 .required()
                 .build());
+
+            cmd.condition(new SubCommandPermissionCondition(subCommands));
         });
     }