fix correct type inference for cache filesystems (#257)

src/datatrove/io.py

@@ -6,6 +6,7 @@
 from fsspec import open as fsspec_open
 from fsspec.callbacks import NoOpCallback, TqdmCallback
 from fsspec.core import get_fs_token_paths, strip_protocol, url_to_fs
+from fsspec.implementations.cached import CachingFileSystem
 from fsspec.implementations.dirfs import DirFileSystem
 from fsspec.implementations.local import LocalFileSystem
 from huggingface_hub import HfFileSystem, cached_assets_path
@@ -137,7 +138,7 @@ def list_files(
             # makes it slightly easier for file extensions
             glob_pattern = f"*{glob_pattern}"
         extra_options = {}
-        if isinstance(self.fs, HfFileSystem):
+        if isinstance(_get_true_fs(self.fs), HfFileSystem):
             extra_options["expand_info"] = False  # speed up
         if include_directories and not glob_pattern:
             extra_options["withdirs"] = True
@@ -374,3 +375,11 @@ def get_shard_from_paths_file(paths_file: DataFileLike, rank: int, world_size):
         for pathi, path in enumerate(f):
             if (pathi - rank) % world_size == 0:
                 yield path.strip()
+
+
+def _get_true_fs(fs: AbstractFileSystem):
+    if isinstance(fs, CachingFileSystem):
+        # We have to unwrap the cached filesystem to get the real fs
+        return fs.fs
+
+    return fs