Bugfix: Stop sequences can be strings

Author: abetlen

llama_cpp/llama.py

@@ -602,7 +602,7 @@ def _create_completion(
         top_p: float = 0.95,
         logprobs: Optional[int] = None,
         echo: bool = False,
-        stop: Optional[List[str]] = [],
+        stop: Optional[Union[str, List[str]]] = [],
         frequency_penalty: float = 0.0,
         presence_penalty: float = 0.0,
         repeat_penalty: float = 1.1,
@@ -624,7 +624,7 @@ def _create_completion(
         )
         text: bytes = b""
         returned_tokens: int = 0
-        stop = stop if stop is not None else []
+        stop = stop if isinstance(stop, list) else [stop] if isinstance(stop, str) else []
         model_name: str = model if model is not None else self.model_path
 
         if self.verbose:
@@ -973,7 +973,7 @@ def create_completion(
         top_p: float = 0.95,
         logprobs: Optional[int] = None,
         echo: bool = False,
-        stop: Optional[List[str]] = [],
+        stop: Optional[Union[str, List[str]]] = [],
         frequency_penalty: float = 0.0,
         presence_penalty: float = 0.0,
         repeat_penalty: float = 1.1,
@@ -1042,7 +1042,7 @@ def __call__(
         top_p: float = 0.95,
         logprobs: Optional[int] = None,
         echo: bool = False,
-        stop: Optional[List[str]] = [],
+        stop: Optional[Union[str, List[str]]] = [],
         frequency_penalty: float = 0.0,
         presence_penalty: float = 0.0,
         repeat_penalty: float = 1.1,
@@ -1162,7 +1162,7 @@ def create_chat_completion(
         top_p: float = 0.95,
         top_k: int = 40,
         stream: bool = False,
-        stop: Optional[List[str]] = [],
+        stop: Optional[Union[str, List[str]]] = [],
         max_tokens: int = 256,
         presence_penalty: float = 0.0,
         frequency_penalty: float = 0.0,
@@ -1188,7 +1188,7 @@ def create_chat_completion(
         Returns:
             Generated chat completion or a stream of chat completion chunks.
         """
-        stop = stop if stop is not None else []
+        stop = stop if isinstance(stop, list) else [stop] if isinstance(stop, str) else []
         chat_history = "".join(
             f'### {"Human" if message["role"] == "user" else "Assistant"}:{message["content"]}'
             for message in messages

llama_cpp/server/app.py

@@ -1,4 +1,5 @@
 import json
+import logging
 import multiprocessing
 from threading import Lock
 from typing import List, Optional, Union, Iterator, Dict
@@ -203,7 +204,7 @@ class CreateCompletionRequest(BaseModel):
         default=False,
         description="Whether to echo the prompt in the generated text. Useful for chatbots.",
     )
-    stop: Optional[List[str]] = stop_field
+    stop: Optional[Union[str, List[str]]] = stop_field
     stream: bool = stream_field
     logprobs: Optional[int] = Field(
         default=None,