fix yaml parser for derived config classes

trl/commands/cli_utils.py

@@ -75,7 +75,9 @@ def merge_dataclasses(self, dataclasses):
                     field_name = data_class_field.name
                     field_value = getattr(dataclass, field_name)
 
-                    if not isinstance(dataclass, TrainingArguments):
+                    if not isinstance(dataclass, TrainingArguments) or not hasattr(
+                        self._dummy_training_args, field_name
+                    ):
                         default_value = data_class_field.default
                     else:
                         default_value = (
@@ -95,12 +97,13 @@ def merge_dataclasses(self, dataclasses):
                                 setattr(dataclasses_copy[i], field_name, value_to_replace)
                         # Otherwise do nothing
 
-                # Re-init `TrainingArguments` to handle all post-processing correctly
+                # Re-init `TrainingArguments` or derived class to handle all post-processing correctly
                 if is_hf_training_args:
-                    init_signature = list(inspect.signature(TrainingArguments.__init__).parameters)
+                    ArgCls = type(dataclass)
+                    init_signature = list(inspect.signature(ArgCls.__init__).parameters)
                     dict_dataclass = asdict(dataclasses_copy[i])
                     new_dict_dataclass = {k: v for k, v in dict_dataclass.items() if k in init_signature}
-                    dataclasses_copy[i] = TrainingArguments(**new_dict_dataclass)
+                    dataclasses_copy[i] = ArgCls(**new_dict_dataclass)
 
         return dataclasses_copy
 
@@ -141,12 +144,16 @@ def warning_handler(message, category, filename, lineno, file=None, line=None):
 
 @dataclass
 class SFTScriptArguments:
-    dataset_name: str = field(default="timdettmers/openassistant-guanaco", metadata={"help": "the dataset name"})
+    dataset_name: str = field(
+        default="timdettmers/openassistant-guanaco",
+        metadata={"help": "the dataset name"},
+    )
     dataset_train_split: str = field(default="train", metadata={"help": "The dataset split to train on"})
     dataset_test_split: str = field(default="test", metadata={"help": "The dataset split to evaluate on"})
     config: str = field(default=None, metadata={"help": "Path to the optional config file"})
     gradient_checkpointing_use_reentrant: bool = field(
-        default=False, metadata={"help": "Whether to apply `use_reentrant` for gradient_checkpointing"}
+        default=False,
+        metadata={"help": "Whether to apply `use_reentrant` for gradient_checkpointing"},
     )
 
 
@@ -166,7 +173,8 @@ class DPOScriptArguments:
     )
     config: str = field(default=None, metadata={"help": "Path to the optional config file"})
     gradient_checkpointing_use_reentrant: bool = field(
-        default=False, metadata={"help": "Whether to apply `use_reentrant` for gradient_checkpointing"}
+        default=False,
+        metadata={"help": "Whether to apply `use_reentrant` for gradient_checkpointing"},
     )
 
 
@@ -229,10 +237,12 @@ class ChatArguments:
         },
     )
     load_in_8bit: bool = field(
-        default=False, metadata={"help": "use 8 bit precision for the base model - works only with LoRA"}
+        default=False,
+        metadata={"help": "use 8 bit precision for the base model - works only with LoRA"},
     )
     load_in_4bit: bool = field(
-        default=False, metadata={"help": "use 4 bit precision for the base model - works only with LoRA"}
+        default=False,
+        metadata={"help": "use 4 bit precision for the base model - works only with LoRA"},
     )
 
     bnb_4bit_quant_type: str = field(default="nf4", metadata={"help": "precise the quantization type (fp4 or nf4)"})
@@ -264,7 +274,10 @@ def post_process_dataclasses(self, dataclasses):
             if dataclass_obj.__class__.__name__ == "TrainingArguments":
                 training_args = dataclass_obj
                 training_args_index = i
-            elif dataclass_obj.__class__.__name__ in ("SFTScriptArguments", "DPOScriptArguments"):
+            elif dataclass_obj.__class__.__name__ in (
+                "SFTScriptArguments",
+                "DPOScriptArguments",
+            ):
                 trl_args = dataclass_obj
             else:
                 ...