Fully remove scarpet commands when apps are unloaded (#1452)

Using new Loader 0.14+ features

src/main/java/carpet/fakes/CommandDispatcherInterface.java

@@ -0,0 +1,5 @@
+package carpet.fakes;
+
+public interface CommandDispatcherInterface {
+    void carpet$unregister(String node);
+}

src/main/java/carpet/fakes/CommandNodeInterface.java

@@ -0,0 +1,5 @@
+package carpet.fakes;
+
+public interface CommandNodeInterface {
+    void carpet$removeChild(String name);
+}

src/main/java/carpet/mixins/CommandDispatcher_scarpetCommandsMixin.java

@@ -0,0 +1,22 @@
+package carpet.mixins;
+
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+
+import com.mojang.brigadier.CommandDispatcher;
+import com.mojang.brigadier.tree.RootCommandNode;
+
+import carpet.fakes.CommandDispatcherInterface;
+import carpet.fakes.CommandNodeInterface;
+
+@Mixin(CommandDispatcher.class)
+public class CommandDispatcher_scarpetCommandsMixin<S> implements CommandDispatcherInterface {
+    @Shadow @Final
+    private RootCommandNode<S> root;
+
+    @Override
+    public void carpet$unregister(String node) {
+        ((CommandNodeInterface)this.root).carpet$removeChild(node);
+    }
+}

src/main/java/carpet/mixins/CommandNode_scarpetCommandsMixin.java

@@ -0,0 +1,30 @@
+package carpet.mixins;
+
+import java.util.Map;
+
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+
+import com.mojang.brigadier.tree.ArgumentCommandNode;
+import com.mojang.brigadier.tree.CommandNode;
+import com.mojang.brigadier.tree.LiteralCommandNode;
+
+import carpet.fakes.CommandNodeInterface;
+
+@Mixin(CommandNode.class)
+public class CommandNode_scarpetCommandsMixin<S> implements CommandNodeInterface {
+    @Shadow @Final
+    private Map<String, CommandNode<S>> children;
+    @Shadow @Final
+    private Map<String, LiteralCommandNode<S>> literals;
+    @Shadow @Final
+    private Map<String, ArgumentCommandNode<S, ?>> arguments;
+    
+    @Override
+    public void carpet$removeChild(String name) {
+        this.children.remove(name);
+        this.literals.remove(name);
+        this.arguments.remove(name);
+    }
+}

src/main/java/carpet/script/CarpetScriptHost.java

@@ -192,7 +192,7 @@ public class CarpetScriptHost extends ScriptHost
         String hostName = main.name();
         Predicate<CommandSourceStack> configValidator = getCommandConfigPermissions();
         LiteralArgumentBuilder<CommandSourceStack> command = literal(hostName).
-               requires((player) -> CarpetServer.scriptServer.modules.containsKey(hostName) && useValidator.test(player) && configValidator.test(player));
+               requires((player) -> useValidator.test(player) && configValidator.test(player));
         for (Pair<List<CommandToken>,FunctionArgument> commandData : entries)
         {
             command = this.addPathToCommand(command, commandData.getKey(), commandData.getValue());
@@ -472,7 +472,7 @@ public class CarpetScriptHost extends ScriptHost
         }
         String hostName = getName();
         LiteralArgumentBuilder<CommandSourceStack> command = literal(hostName).
-                requires((player) -> scriptServer().modules.containsKey(hostName) && commandValidator.test(player) && configValidator.test(player)).
+                requires((player) -> commandValidator.test(player) && configValidator.test(player)).
                 executes( (c) ->
                 {
                     CarpetScriptHost targetHost = scriptServer().modules.get(hostName).retrieveOwnForExecution(c.getSource());
@@ -505,7 +505,7 @@ public class CarpetScriptHost extends ScriptHost
             {
                 command = command.
                         then(literal(function).
-                                requires((player) -> scriptServer().modules.containsKey(hostName) && scriptServer().modules.get(hostName).getFunction(function) != null).
+                                requires((player) -> scriptServer().modules.get(hostName).getFunction(function) != null).
                                 executes((c) -> {
                                     CarpetScriptHost targetHost = scriptServer().modules.get(hostName).retrieveOwnForExecution(c.getSource());
                                     Value response = targetHost.handleCommandLegacy(c.getSource(),function, null, "");

src/main/java/carpet/script/CarpetScriptServer.java

@@ -1,6 +1,7 @@
 package carpet.script;
 
 import carpet.CarpetSettings;
+import carpet.fakes.CommandDispatcherInterface;
 import carpet.script.annotation.AnnotationParser;
 import carpet.script.api.Auxiliary;
 import carpet.script.api.BlockIterators;
@@ -343,6 +344,7 @@ public class CarpetScriptServer extends ScriptServer
         events.removeAllHostEvents(modules.get(name));
         modules.get(name).onClose();
         modules.remove(name);
+        ((CommandDispatcherInterface)server.getCommands().getDispatcher()).carpet$unregister(name);
         if (!isRuleApp) unloadableModules.remove(name);
         CommandHelper.notifyPlayersCommandsChanged(server);
         if (notifySource) Messenger.m(source, "gi Removed "+name+" app");