Add equality checking to each command node

src/main/java/net/minecraft/commands/tree/ArgumentCommandNode.java

@@ -38,4 +38,26 @@ public class ArgumentCommandNode<T> extends CommandNode {
             return "";
         }
     }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof ArgumentCommandNode)) return false;
+
+        ArgumentCommandNode that = (ArgumentCommandNode) o;
+
+        if (!name.equals(that.name)) return false;
+        if (!type.equals(that.type)) return false;
+        if (!getChildren().equals(that.getChildren())) return false;
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        int result = name.hashCode();
+        result = 31 * result + type.hashCode();
+        result = 31 * result + getChildren().hashCode();
+        return result;
+    }
 }

src/main/java/net/minecraft/commands/tree/LiteralCommandNode.java

@@ -29,4 +29,24 @@ public class LiteralCommandNode extends CommandNode {
         int start = expected.length();
         return command.substring(start);
     }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof LiteralCommandNode)) return false;
+
+        LiteralCommandNode that = (LiteralCommandNode) o;
+
+        if (!literal.equals(that.literal)) return false;
+        if (!getChildren().equals(that.getChildren())) return false;
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        int result = literal.hashCode();
+        result = 31 * result + getChildren().hashCode();
+        return result;
+    }
 }

src/main/java/net/minecraft/commands/tree/RootCommandNode.java

@@ -13,4 +13,21 @@ public class RootCommandNode extends CommandNode {
     public String parse(String command, CommandContextBuilder contextBuilder) throws IllegalArgumentSyntaxException, ArgumentValidationException {
         return command;
     }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof RootCommandNode)) return false;
+
+        RootCommandNode that = (RootCommandNode) o;
+
+        if (!getChildren().equals(that.getChildren())) return false;
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        return getChildren().hashCode();
+    }
 }