wrap prepared_ds_path in str() to avoid TypeError in fsspec package (#1548)

* wrap prepared_ds_path in str() to avoid TypeError in fsspec package

`fsspec` calls `if "::" in path` on `prepared_ds_path`, which will throw an error if it is a `PosixPath` object.

* update test too

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Co-authored-by: Wing Lian <wing.lian@gmail.com>

src/axolotl/utils/data/sft.py

@@ -421,7 +421,7 @@ def load_tokenized_prepared_datasets(
 
         if cfg.local_rank == 0:
             LOG.info(f"Saving merged prepared dataset to disk... {prepared_ds_path}")
-            dataset.save_to_disk(prepared_ds_path)
+            dataset.save_to_disk(str(prepared_ds_path))
             if cfg.push_dataset_to_hub:
                 LOG.info(
                     f"Saving merged prepared dataset with push_to_hub... {cfg.push_dataset_to_hub}/{ds_hash}"

tests/test_datasets.py

@@ -110,7 +110,7 @@ class TestDatasetPreparation(unittest.TestCase):
         """Usual use case.  Verify datasets saved via `save_to_disk` can be loaded."""
         with tempfile.TemporaryDirectory() as tmp_dir:
             tmp_ds_name = Path(tmp_dir) / "tmp_dataset"
-            self.dataset.save_to_disk(tmp_ds_name)
+            self.dataset.save_to_disk(str(tmp_ds_name))
 
             prepared_path = Path(tmp_dir) / "prepared"
             cfg = DictDefault(