craftbukkit/nms-patches/net/minecraft/server/commands/CommandList.patch

--- a/net/minecraft/server/commands/CommandList.java
+++ b/net/minecraft/server/commands/CommandList.java
@@ -35,7 +35,14 @@
 
     private static int format(CommandListenerWrapper commandlistenerwrapper, Function<EntityPlayer, IChatBaseComponent> function) {
         PlayerList playerlist = commandlistenerwrapper.getServer().getPlayerList();
-        List<EntityPlayer> list = playerlist.getPlayers();
+        // CraftBukkit start
+        List<EntityPlayer> players = playerlist.getPlayers();
+        if (commandlistenerwrapper.getBukkitSender() instanceof org.bukkit.entity.Player) {
+            org.bukkit.entity.Player sender = (org.bukkit.entity.Player) commandlistenerwrapper.getBukkitSender();
+            players = players.stream().filter((ep) -> sender.canSee(ep.getBukkitEntity())).collect(java.util.stream.Collectors.toList());
+        }
+        List<EntityPlayer> list = players;
+        // CraftBukkit end
         IChatBaseComponent ichatbasecomponent = ChatComponentUtils.formatList(list, function);
 
         commandlistenerwrapper.sendSuccess(() -> {