simplify code

Former-commit-id: d3731754ab7c28ae81f60784e0e4213f279d93fe

src/llmtuner/tuner/pt/workflow.py

@@ -4,7 +4,7 @@ import math
 from typing import Optional, List
 from transformers import Seq2SeqTrainingArguments, DataCollatorForSeq2Seq, TrainerCallback
 
-from llmtuner.dsets import get_dataset, preprocess_dataset
+from llmtuner.dsets import get_dataset, preprocess_dataset, split_dataset
 from llmtuner.extras.callbacks import LogCallback
 from llmtuner.extras.constants import IGNORE_INDEX
 from llmtuner.extras.ploting import plot_loss
@@ -28,16 +28,6 @@ def run_pt(
         label_pad_token_id=IGNORE_INDEX if data_args.ignore_pad_token_for_loss else tokenizer.pad_token_id
     )
 
-    # Split the dataset
-    if training_args.do_train:
-        if data_args.dev_ratio > 1e-6:
-            dataset = dataset.train_test_split(test_size=data_args.dev_ratio)
-            trainer_kwargs = {"train_dataset": dataset["train"], "eval_dataset": dataset["test"]}
-        else:
-            trainer_kwargs = {"train_dataset": dataset}
-    else: # do_eval or do_predict
-        trainer_kwargs = {"eval_dataset": dataset}
-
     # Initialize our Trainer
     trainer = PeftTrainer(
         finetuning_args=finetuning_args,
@@ -46,7 +36,7 @@ def run_pt(
         tokenizer=tokenizer,
         data_collator=data_collator,
         callbacks=callbacks,
-        **trainer_kwargs
+        **split_dataset(dataset, data_args.dev_ratio, training_args.do_train)
     )
 
     # Training