Handle other reasoning trace dataset formats (axolotl-ai-cloud#2591)

* Handle other reasoning trace dataset formats

* rename var to improve readability

* chore: refactor with comments

---------

Co-authored-by: NanoCode012 <[email protected]>

Author: winglian

src/axolotl/prompt_strategies/chat_template.py

@@ -42,6 +42,7 @@ def __init__(
             message_property_mappings = {
                 "role": "role",
                 "content": "content",
+                "reasoning_content": "reasoning_content",
             }
 
         if roles:
@@ -661,16 +662,46 @@ def transform_message(self, message):
         # if the role is assistant that we want to use reasoning_content
         if self.split_thinking and transformed_message["role"] == "assistant":
             content = transformed_message["content"]
-            pairs = [("<think>", "</think>"), ("<reasoning>", "</reasoning>")]
-            for pair in pairs:
-                if pair[0] in content and pair[1] in content:
-                    start_idx = content.find(pair[0])
-                    end_idx = content.find(pair[1])
-                    thinking_content = content[start_idx + len(pair[0]) : end_idx]
+            thinking_pairs = [
+                ("<think>", "</think>"),
+                ("<reasoning>", "</reasoning>"),
+                ("<|begin_of_thought|>", "<|end_of_thought|>"),
+            ]
+            content_pairs = [("<|begin_of_solution|>", "<|end_of_solution|>")]
+            for tpair in thinking_pairs:
+                # check if the thinking pair is in the content
+                if tpair[0] in content and tpair[1] in content:
+                    # find the start and end index of the thinking pair
+                    t_start_idx = content.find(tpair[0])
+                    t_end_idx = content.find(tpair[1])
+
+                    # get the thinking content
+                    thinking_content = content[t_start_idx + len(tpair[0]) : t_end_idx]
                     transformed_message["reasoning_content"] = thinking_content.strip()
-                    transformed_message["content"] = content[
-                        end_idx + len(pair[1]) :
-                    ].lstrip()
+
+                    # take remainder of the content
+                    # strip whitespace from beginning of the remainder (thinking tokens)
+                    remainder = content[t_end_idx + len(tpair[1]) :].lstrip()
+
+                    # check if the content pair is in the remainder
+                    cpair_found = False
+                    for cpair in content_pairs:
+                        if cpair[0] in remainder and cpair[1] in remainder:
+                            # find the start and end index of the content pair
+                            c_start_idx = remainder.find(cpair[0])
+                            c_end_idx = remainder.find(cpair[1])
+
+                            # get the content content
+                            content_content = remainder[
+                                c_start_idx + len(cpair[0]) : c_end_idx
+                            ]
+                            transformed_message["content"] = content_content.strip()
+                            cpair_found = True
+                            break
+
+                    # else, the content is the remainder
+                    if not cpair_found:
+                        transformed_message["content"] = remainder
                     break
 
         # Determine which keys in the original message were not mapped

tests/prompt_strategies/test_chat_templates_thinking.py

@@ -34,7 +34,31 @@ def messages_w_reasoning_fixture():
                         "content": "<think>lorem</think>\nwelcome",
                     },
                 ]
-            }
+            },
+            {
+                "messages": [
+                    {
+                        "role": "user",
+                        "content": "hello",
+                    },
+                    {
+                        "role": "assistant",
+                        "content": "<|begin_of_thought|>lorem<|end_of_thought|>\n<|begin_of_solution|>welcome\n<|end_of_solution|>",
+                    },
+                ]
+            },
+            {
+                "messages": [
+                    {
+                        "role": "user",
+                        "content": "hello",
+                    },
+                    {
+                        "role": "assistant",
+                        "content": "<reasoning>lorem</reasoning>\nwelcome",
+                    },
+                ]
+            },
         ]
     )
 
@@ -83,36 +107,37 @@ def test_splits_think(self, messages_w_reasoning, qwen3_tokenizer):
                 }
             ),
         )
-        transformed_prompt = strategy.get_conversation_thread(messages_w_reasoning[0])
-        assert transformed_prompt[0]["role"] == "user"
-        assert transformed_prompt[1]["role"] == "assistant"
-        assert transformed_prompt[1]["reasoning_content"] == "lorem"
-        assert transformed_prompt[1]["content"] == "welcome"
+        for conversation in messages_w_reasoning:
+            transformed_prompt = strategy.get_conversation_thread(conversation)
+            assert transformed_prompt[0]["role"] == "user"
+            assert transformed_prompt[1]["role"] == "assistant"
+            assert transformed_prompt[1]["reasoning_content"] == "lorem"
+            assert transformed_prompt[1]["content"] == "welcome"
 
-        res = strategy.tokenize_prompt(messages_w_reasoning[0])
-        input_ids = res["input_ids"]
-        # fmt: off
-        expected_input_ids = [
-            151644,  # im_start
-            872,  # user
-            198,  # \n
-            14990,  # hello
-            151645,  # im_end
-            198,  # \n
-            151644,  # im_start
-            77091,  # assistant
-            198,  # \n
-            151667,  # think
-            198,  # \n
-            385, 1826,  # lorem
-            198,  # \n
-            151668,  # /think
-            271,  # \n
-            34084,  # welcome
-            151645,  # im_end
-            198,  # \n
-        ]
-        # fmt: on
-        assert (
-            input_ids == expected_input_ids
-        ), f"Input IDs mismatch: {input_ids} != {expected_input_ids}"
+            res = strategy.tokenize_prompt(conversation)
+            input_ids = res["input_ids"]
+            # fmt: off
+            expected_input_ids = [
+                151644,  # im_start
+                872,  # user
+                198,  # \n
+                14990,  # hello
+                151645,  # im_end
+                198,  # \n
+                151644,  # im_start
+                77091,  # assistant
+                198,  # \n
+                151667,  # think
+                198,  # \n
+                385, 1826,  # lorem
+                198,  # \n
+                151668,  # /think
+                271,  # \n
+                34084,  # welcome
+                151645,  # im_end
+                198,  # \n
+            ]
+            # fmt: on
+            assert (
+                input_ids == expected_input_ids
+            ), f"Input IDs mismatch: {input_ids} != {expected_input_ids}"