feat: convert MistralTokenizer AssertionError to ValueError

Signed-off-by: Guillaume Calmettes <gcalmettes@scaleway.com>

Author: gcalmettes

vllm/entrypoints/chat_utils.py

@@ -1193,8 +1193,16 @@ def apply_mistral_chat_template(
         **kwargs,
     )
 
-    return tokenizer.apply_chat_template(
+    try:
+        tokens_ids = tokenizer.apply_chat_template(
         messages=messages,
         tools=tools,
         **kwargs,
-    )
+        )
+    # mistral-common uses assert statements to stop processing of input
+    # if input does not comply with the expected format.
+    # We convert those assertion errors to ValueErrors so they can be
+    # are properly caught in the preprocessing_input step
+    except AssertionError as e:
+        raise ValueError from e
+    return tokens_ids