From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: stonar96 <minecraft.stonar96@gmail.com>
Date: Sun, 12 Sep 2021 00:14:21 +0200
Subject: [PATCH] Check requirement before suggesting root nodes

Child nodes are handled by CommandDispatcher#parse checking
requirements.

Vanilla clients only send ServerboundCommandSuggestionPacket when
encountering a command node with ASK_SERVER suggestions, however a
modified client can send this packet whenever it wants.

diff --git a/src/main/java/com/mojang/brigadier/CommandDispatcher.java b/src/main/java/com/mojang/brigadier/CommandDispatcher.java
index ca24830bac1a04b798229d1946863429c7849495..5584040fe48c18aa809f5a1510157e735851df79 100644
--- a/src/main/java/com/mojang/brigadier/CommandDispatcher.java
+++ b/src/main/java/com/mojang/brigadier/CommandDispatcher.java
@@ -594,10 +594,14 @@ public class CommandDispatcher<S> {
         int i = 0;
         for (final CommandNode<S> node : parent.getChildren()) {
             CompletableFuture<Suggestions> future = Suggestions.empty();
+            // Paper start - Don't suggest if the requirement isn't met
+            if (parent != this.root || node.canUse(context.getSource())) {
             try {
                 future = node.listSuggestions(context.build(truncatedInput), new SuggestionsBuilder(truncatedInput, truncatedInputLowerCase, start));
             } catch (final CommandSyntaxException ignored) {
             }
+            }
+            // Paper end
             futures[i++] = future;
         }