From 9376c9064b4ec0ffeec6e5a95048aed03e1e3a18 Mon Sep 17 00:00:00 2001
From: majiayu000 <1835304752@qq.com>
Date: Mon, 29 Dec 2025 13:45:07 +0800
Subject: [PATCH] fix: add revision parameter support and escape quotes in chat
 templates

- Fix #3544: Add revision parameter to AutoConfig, AutoModelForCausalLM,
  AutoModelForSequenceClassification, and load_correct_tokenizer calls
  in FastLlamaModel.from_pretrained. This enables loading specific model
  revisions/branches from HuggingFace Hub.

- Fix #3667: Escape single quotes in system messages before substituting
  into Jinja2 templates. This prevents TemplateSyntaxError when system
  messages contain apostrophes (e.g., "user's" in Vicuna templates).

Signed-off-by: majiayu000 <1835304752@qq.com>
(cherry picked from commit b0a6e4154b1bca9ed9bc06bdd1a83da1007dd6bf)
---
 unsloth/chat_templates.py  | 8 ++++++--
 unsloth/models/llama.py    | 4 ++++
 unsloth/tokenizer_utils.py | 5 +++++
 3 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/unsloth/chat_templates.py b/unsloth/chat_templates.py
index 35eb871529..50e7a1f380 100644
--- a/unsloth/chat_templates.py
+++ b/unsloth/chat_templates.py
@@ -1667,14 +1667,18 @@ def _change_system_message(template: str, type_chat_template: str, system_messag
         if has_placeholder:
             if system_message is None:
                 raise ValueError("Unsloth: You need to provide a system message for custom templates.")
-            new_template = re.sub(system_message_pattern, system_message, template)
+            # Escape single quotes to prevent Jinja2 template syntax errors
+            escaped_message = system_message.replace("'", "\\'")
+            new_template = re.sub(system_message_pattern, escaped_message, template)
             return new_template, system_message
 
         return template, system_message
 
     # For predefined templates with default system message
     message_to_use = system_message if system_message is not None else default_system_message
-    new_template = re.sub(system_message_pattern, message_to_use, template)
+    # Escape single quotes to prevent Jinja2 template syntax errors
+    escaped_message = message_to_use.replace("'", "\\'")
+    new_template = re.sub(system_message_pattern, escaped_message, template)
 
     return new_template, message_to_use
 
diff --git a/unsloth/models/llama.py b/unsloth/models/llama.py
index 93d93e26d6..0498c11734 100644
--- a/unsloth/models/llama.py
+++ b/unsloth/models/llama.py
@@ -2331,6 +2331,7 @@ class FastLlamaModel:
             model_name,
             token = token,
             attn_implementation = "sdpa",
+            revision = revision,
         )
         model_config.model_name = model_name
         model_max_seq_length = model_config.max_position_embeddings
@@ -2424,6 +2425,7 @@ class FastLlamaModel:
                 max_position_embeddings = max_position_embeddings,
                 trust_remote_code = trust_remote_code,
                 attn_implementation = preferred_attn_impl,
+                revision = revision,
                 **kwargs,
             )
         elif not fast_inference:
@@ -2436,6 +2438,7 @@ class FastLlamaModel:
                 max_position_embeddings = max_position_embeddings,
                 trust_remote_code = trust_remote_code,
                 attn_implementation = preferred_attn_impl,
+                revision = revision,
                 **kwargs,
             )
             model.fast_generate = make_fast_generate_wrapper(model.generate)
@@ -2505,6 +2508,7 @@ class FastLlamaModel:
             token = token,
             trust_remote_code = trust_remote_code,
             fix_tokenizer = fix_tokenizer,
+            revision = revision,
         )
 
         model, tokenizer = patch_tokenizer(model, tokenizer)
diff --git a/unsloth/tokenizer_utils.py b/unsloth/tokenizer_utils.py
index c445879df7..ccd0249209 100644
--- a/unsloth/tokenizer_utils.py
+++ b/unsloth/tokenizer_utils.py
@@ -503,6 +503,7 @@ def _load_correct_tokenizer(
     trust_remote_code = False,
     cache_dir = "huggingface_tokenizers_cache",
     fix_tokenizer = True,
+    revision = None,
 ):
     if IS_COLAB_ENVIRONMENT:
         cache_dir = cache_dir
@@ -528,6 +529,7 @@ def _load_correct_tokenizer(
             legacy = False,
             from_slow = True,
             cache_dir = cache_dir,
+            revision = revision,
         )
     except:
         slow_tokenizer = None
@@ -546,6 +548,7 @@ def _load_correct_tokenizer(
         token = token,
         trust_remote_code = trust_remote_code,
         cache_dir = cache_dir,
+        revision = revision,
     )
 
     if not fix_tokenizer or tokenizer_name in IGNORED_TOKENIZER_NAMES:
@@ -587,6 +590,7 @@ def load_correct_tokenizer(
     trust_remote_code = False,
     cache_dir = "huggingface_tokenizers_cache",
     fix_tokenizer = True,
+    revision = None,
 ):
     tokenizer = _load_correct_tokenizer(
         tokenizer_name = tokenizer_name,
@@ -596,6 +600,7 @@ def load_correct_tokenizer(
         trust_remote_code = trust_remote_code,
         cache_dir = cache_dir,
         fix_tokenizer = fix_tokenizer,
+        revision = revision,
     )
 
     ### 1. Fixup tokenizer's chat_template