move no highlight catch logic

demo_watermark.py

@@ -392,6 +392,11 @@ def detect(input_text, args, tokenizer, device=None, return_green_token_mask=Tru
                                         normalizers=args.normalizers,
                                         ignore_repeated_bigrams=args.ignore_repeated_bigrams,
                                         select_green_tokens=args.select_green_tokens)
+    # for now, just don't display the green token mask 
+    # if we're using normalizers or ignore_repeated_bigrams
+    if args.normalizers != [] or args.ignore_repeated_bigrams:
+        return_green_token_mask = False
+    
     error = False
     green_token_mask = None
     if input_text == "":
@@ -408,12 +413,7 @@ def detect(input_text, args, tokenizer, device=None, return_green_token_mask=Tru
         output = [["Error","string too short to compute metrics"]]
         output += [["",""] for _ in range(6)]
 
-    # for now, just don't display the green token mask 
-    # if we're using normalizers or ignore_repeated_bigrams
-    if args.normalizers != [] or args.ignore_repeated_bigrams:
-        green_token_mask = None
-
-    html_output = ""
+    html_output = "[No highlight markup generated]"
     if green_token_mask is not None:
         # hack bc we need a fast tokenizer with charspan support
         if "opt" in args.model_name_or_path: