Fix datapack exception related to EnumArgument with siblings (#7686)

Invalid enum constants are now properly thrown as a CommandSyntaxException

src/main/java/net/minecraftforge/server/command/EnumArgument.java

@@ -24,18 +24,23 @@ import com.mojang.brigadier.StringReader;
 import com.mojang.brigadier.arguments.ArgumentType;
 import com.mojang.brigadier.context.CommandContext;
 import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.exceptions.Dynamic2CommandExceptionType;
 import com.mojang.brigadier.suggestion.Suggestions;
 import com.mojang.brigadier.suggestion.SuggestionsBuilder;
 import net.minecraft.command.ISuggestionProvider;
 import net.minecraft.command.arguments.IArgumentSerializer;
 import net.minecraft.network.PacketBuffer;
+import net.minecraft.util.text.TranslationTextComponent;
 
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.concurrent.CompletableFuture;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 public class EnumArgument<T extends Enum<T>> implements ArgumentType<T> {
+    private static final Dynamic2CommandExceptionType INVALID_ENUM = new Dynamic2CommandExceptionType(
+            (found, constants) -> new TranslationTextComponent("commands.forge.arguments.enum.invalid", constants, found));
     private final Class<T> enumClass;
 
     public static <R extends Enum<R>> EnumArgument<R> enumArgument(Class<R> enumClass) {
@@ -47,7 +52,12 @@ public class EnumArgument<T extends Enum<T>> implements ArgumentType<T> {
 
     @Override
     public T parse(final StringReader reader) throws CommandSyntaxException {
-        return Enum.valueOf(enumClass, reader.readUnquotedString());
+        String name = reader.readUnquotedString();
+        try {
+            return Enum.valueOf(enumClass, name);
+        } catch (IllegalArgumentException e) {
+            throw INVALID_ENUM.createWithContext(reader, name, Arrays.toString(enumClass.getEnumConstants()));
+        }
     }
 
     @Override