Use max tokens from options in mlx_lm evaluate (#1302)

llms/mlx_lm/evaluate.py

@@ -289,17 +289,15 @@ def generate_until(self, requests) -> list[str]:
         contexts, options = zip(*[req.args for req in requests])
         # contrary to the doc the second element of the tuple contains
         # {'do_sample': False, 'until': ['\n\n'], 'temperature': 0}
-        keys = list(options[0].keys())
-        assert "until" in keys
-        untils = [x["until"] for x in options]
         completions = []
 
-        for context, until in tqdm(zip(contexts, untils), total=len(contexts)):
+        for context, opt in tqdm(zip(contexts, options), total=len(contexts)):
+            until = opt["until"]
             context = self.tokenizer.encode(
                 context, add_special_tokens=not self.use_chat_template
             )
             max_tokens = min(
-                self._max_tokens,
+                opt.get("max_gen_tokens", self._max_tokens),
                 self.tokenizer.model_max_length - len(context),
             )
             text = ""
@@ -334,9 +332,9 @@ def main():
     )
     parser.add_argument(
         "--limit",
-        default=1.0,
+        default=100,
         help="Limit the number of examples per task.",
-        type=float,
+        type=int,
     )
     parser.add_argument("--seed", type=int, default=123, help="Random seed.")
     parser.add_argument(