Configuration argument overriding by deprecated default values

[qgallouedec]

For a many deprecated args, you need to pass them it in the config and in the trainer, otherwise it will be overwritten by the default value of the trainer. Example with num_of_sequences and SFTTrainer:

>>> from trl import SFTConfig, SFTTrainer
>>> args = SFTConfig("tmp", num_of_sequences=32)
>>> trainer = SFTTrainer("gpt2", args=args)
/fsx/qgallouedec/trl/trl/trainer/sft_trainer.py:185: UserWarning: You passed a model_id to the SFTTrainer. This will automatically create an `AutoModelForCausalLM` or a `PeftModel` (if you passed a `peft_config`) for you.
  warnings.warn(
/fsx/qgallouedec/trl/trl/trainer/sft_trainer.py:289: UserWarning: You didn't pass a `max_seq_length` argument to the SFTTrainer, this will default to 1024
  warnings.warn(
/fsx/qgallouedec/trl/trl/trainer/sft_trainer.py:352: UserWarning: You passed a `num_of_sequences` argument to the SFTTrainer, the value you passed will override the one in the `SFTConfig`.
  warnings.warn(
>>> trainer.args.num_of_sequences
1024

If wrongly report that I've passed a num_of_sequences argument to the SFTTrainer. And the value that I've set in SFTConfig is overwritten by the trainer's default (1024). The only way to make it work as expected is to use

args = SFTConfig("tmp", num_of_sequences=32)
trainer = SFTTrainer("gpt2", args=args, num_of_sequences=32)

which is not satisfying, since it create a duplicate, and it uses a deprecated arg.