NyssaW/github-issues huggingface dataset:
`load_dataset` fails to load dataset saved by `save_to_disk`

### Describe the bug

This code fails to load the dataset it just saved:

```python
from datasets import load_dataset
from transformers import AutoTokenizer

MODEL = "google-bert/bert-base-cased"
tokenizer = AutoTokenizer.from_pretrained(MODEL)

dataset = load_dataset("yelp_review_full")

def tokenize_function(examples):
    return tokenizer(examples["text"], padding="max_length", truncation=True)

tokenized_datasets = dataset.map(tokenize_function, batched=True)
tokenized_datasets.save_to_disk("dataset")

tokenized_datasets = load_dataset("dataset/")  # raises
```

It raises `ValueError: Couldn't infer the same data file format for all splits. Got {NamedSplit('train'): ('arrow', {}), NamedSplit('test'): ('json', {})}`.

I believe this bug is caused by the [logic that tries to infer dataset format](https://github.com/huggingface/datasets/blob/9af8dd3de7626183a9a9ec8973cebc672d690400/src/datasets/load.py#L556). It counts the most common file extension. However, a small dataset can fit in a single `.arrow` file and have two JSON metadata files, causing the format to be inferred as JSON:

```shell
$ ls -l dataset/test
-rw-r--r-- 1 sliedes sliedes 191498784 Jul  1 13:55 data-00000-of-00001.arrow
-rw-r--r-- 1 sliedes sliedes      1730 Jul  1 13:55 dataset_info.json
-rw-r--r-- 1 sliedes sliedes       249 Jul  1 13:55 state.json
```

### Steps to reproduce the bug

Execute the code above.

### Expected behavior

The dataset is loaded successfully.

### Environment info

- `datasets` version: 2.20.0
- Platform: Linux-6.9.3-arch1-1-x86_64-with-glibc2.39
- Python version: 3.12.4
- `huggingface_hub` version: 0.23.4
- PyArrow version: 16.1.0
- Pandas version: 2.2.2
- `fsspec` version: 2024.5.0


Comments:
In my case the error was:
```
ValueError: You are trying to load a dataset that was saved using `save_to_disk`. Please use `load_from_disk` instead.
```
Did you try `load_from_disk`?

More generally, any reason there is no API consistency between save_to_disk and push_to_hub ? 

Would be nice to be able to save_to_disk and then upload manually to the hub and load_dataset (which works in some situations but not all)...

I have the exact same problem !

`load_from_disk` managed to load the dataset, but the bug with `load_dataset` needs to be fixed. 

any update ? I need some function from load dataset like num_proc, or streaming to optimize ram, ... but got this error

I found that the very hard way. When each split has more than one arrow file they are marked correctly. When there is only one, json file wins.
So adding the .arrow format in the sorter does the trick.
CI is broken for faiss tests on Windows: node down: Not properly terminated

Faiss tests on Windows make the CI run indefinitely until maximum execution time (360 minutes) is reached.

See: https://github.com/huggingface/datasets/actions/runs/9712659783
```
test (integration, windows-latest, deps-minimum)
The job running on runner GitHub Actions 60 has exceeded the maximum execution time of 360 minutes.
test (integration, windows-latest, deps-latest)
The job running on runner GitHub Actions 238 has exceeded the maximum execution time of 360 minutes.
```
```
____________________________ tests/test_search.py _____________________________
[gw1] win32 -- Python 3.8.10 C:\hostedtoolcache\windows\Python\3.8.10\x64\python.exe
worker 'gw1' crashed while running 'tests/test_search.py::IndexableDatasetTest::test_add_faiss_index'
____________________________ tests/test_search.py _____________________________
[gw2] win32 -- Python 3.8.10 C:\hostedtoolcache\windows\Python\3.8.10\x64\python.exe
worker 'gw2' crashed while running 'tests/test_search.py::IndexableDatasetTest::test_add_faiss_index'
```
```
tests/test_search.py::IndexableDatasetTest::test_add_faiss_index 
[gw0] node down: Not properly terminated
[gw0] FAILED tests/test_search.py::IndexableDatasetTest::test_add_faiss_index 

replacing crashed worker gw0

tests/test_search.py::IndexableDatasetTest::test_add_faiss_index 
[gw1] node down: Not properly terminated
[gw1] FAILED tests/test_search.py::IndexableDatasetTest::test_add_faiss_index 

replacing crashed worker gw1

tests/test_search.py::IndexableDatasetTest::test_add_faiss_index 
[gw2] node down: Not properly terminated
[gw2] FAILED tests/test_search.py::IndexableDatasetTest::test_add_faiss_index 

replacing crashed worker gw2
```

Comments:
CI is broken after ruff-0.5.0: E721

After ruff-0.5.0 release (https://github.com/astral-sh/ruff/releases/tag/0.5.0), our CI is broken due to E721 rule. 

See: https://github.com/huggingface/datasets/actions/runs/9707641618/job/26793170961?pr=6983
> src/datasets/features/features.py:844:12: E721 Use `is` and `is not` for type comparisons, or `isinstance()` for isinstance checks

Comments:
Datasetbuilder Local Download FileNotFoundError

### Describe the bug

So I was trying to download a dataset and save it as parquet and I follow the [tutorial](https://huggingface.co/docs/datasets/filesystems#download-and-prepare-a-dataset-into-a-cloud-storage) of Huggingface. However, during the excution I face a FileNotFoundError.

I debug the code and it seems there is a bug there:
So first it creates a .incomplete folder and before moving its contents the following code deletes the directory
[Code](https://github.com/huggingface/datasets/blob/98fdc9e78e6d057ca66e58a37f49d6618aab8130/src/datasets/builder.py#L984)
hence as a result I face with: 

``` FileNotFoundError: [Errno 2] No such file or directory: '~/data/Parquet/.incomplete '```

### Steps to reproduce the bug

```
from datasets import load_dataset_builder
from pathlib import Path

parquet_dir = "~/data/Parquet/" 
Path(parquet_dir).mkdir(parents=True, exist_ok=True)
builder = load_dataset_builder(
    "rotten_tomatoes",
)
builder.download_and_prepare(parquet_dir, file_format="parquet")
```

### Expected behavior

Downloads the files and saves as parquet

### Environment info

Ubuntu,
Python 3.10
```
datasets 2.19.1
```

Comments:
Ok it seems the solution is to use the directory string without the trailing "/" which in my case  as: 

`parquet_dir = "~/data/Parquet" `

Still i think this is a weird behavior...
IterableDataset: Unsupported ScalarType BFloat16

### Describe the bug

`IterableDataset.from_generator` crashes when using BFloat16:

```
  File "/usr/local/lib/python3.11/site-packages/datasets/utils/_dill.py", line 169, in _save_torchTensor
    args = (obj.detach().cpu().numpy(),)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^

TypeError: Got unsupported ScalarType BFloat16
```

### Steps to reproduce the bug

```python
import torch
from datasets import IterableDataset


def demo(x):
    yield {"x": x}


x = torch.tensor([1.], dtype=torch.bfloat16)

dataset = IterableDataset.from_generator(
    demo,
    gen_kwargs=dict(x=x),
)

example = next(iter(dataset))
print(example)
```

### Expected behavior

Code sample should print:
```python
{'x': tensor([1.], dtype=torch.bfloat16)}
```

### Environment info

```
datasets==2.20.0
torch==2.2.2
```

Comments:
@lhoestq Thank you for merging #6607, but unfortunately the issue persists for `IterableDataset` :pensive: 

Hi ! I opened https://github.com/huggingface/datasets/pull/7002 to fix this bug

Amazing, thank you so much @lhoestq! :pray:
CI is broken for tests using hf-internal-testing/librispeech_asr_dummy

CI is broken: https://github.com/huggingface/datasets/actions/runs/9657882317/job/26637998686?pr=6996
```
FAILED tests/test_inspect.py::test_get_dataset_config_names[hf-internal-testing/librispeech_asr_dummy-expected4] - AssertionError: assert ['clean'] == ['clean', 'other']
  
  Right contains one more item: 'other'
  
  Full diff:
    [
        'clean',
  -     'other',
    ]
FAILED tests/test_inspect.py::test_get_dataset_default_config_name[hf-internal-testing/librispeech_asr_dummy-None] - AssertionError: assert 'clean' is None
```

Note that repository was recently converted to Parquet: https://huggingface.co/datasets/hf-internal-testing/librispeech_asr_dummy/commit/5be91486e11a2d616f4ec5db8d3fd248585ac07a

Comments:
Problematic rank after calling `split_dataset_by_node` twice

### Describe the bug

I'm trying to split `IterableDataset` by `split_dataset_by_node`.
But when doing split on a already split dataset, the resulting `rank` is greater than `world_size`.

### Steps to reproduce the bug

Here is the minimal code for reproduction:
```py
>>> from datasets import load_dataset
>>> from datasets.distributed import split_dataset_by_node
>>> dataset = load_dataset('fla-hub/slimpajama-test', split='train', streaming=True)      
>>> dataset = split_dataset_by_node(dataset, 1, 32)
>>> dataset._distributed
DistributedConfig(rank=1, world_size=32)
>>> dataset = split_dataset_by_node(dataset, 1, 15)
>>> dataset._distributed                           
DistributedConfig(rank=481, world_size=480)
```
As you can see, the second rank 481 > 480, which is problematic.

### Expected behavior

I think this error comes from this line @lhoestq
https://github.com/huggingface/datasets/blob/a6ccf944e42c1a84de81bf326accab9999b86c90/src/datasets/iterable_dataset.py#L2943-L2944
We may need to obtain the rank first. Then the above code gives
```py
>>> dataset._distributed                           
DistributedConfig(rank=16, world_size=480)
```

### Environment info

datasets==2.20.0

Comments:
ah yes good catch ! feel free to open a PR with your suggested fix
Convert polars DataFrame back to datasets

### Feature request

This returns error.
```python
from datasets import Dataset

dsdf = Dataset.from_dict({"x": [[1, 2], [3, 4, 5]], "y": ["a", "b"]})
Dataset.from_polars(dsdf.to_polars())
```
ValueError: Arrow type large_list<item: int64> does not have a datasets dtype equivalent.

### Motivation

When datasets contain Sequence data type, it will be converted to Arrow type large_list. However, the reverse (from large_list to Sequence) does not work.

### Your contribution

No

Comments:
Hi ! Thanks for reporting :)

We don't support `large_list` yet, though it should be added to `Sequence` IMO (maybe with a parameter `large=True` ?)
Support NumPy 2.0

### Feature request

Support NumPy 2.0.

### Motivation

NumPy introduces the Array API, which bridges the gap between machine learning libraries.  Many clients of HuggingFace are eager to start using the Array API.

Besides that, NumPy 2 provides a cleaner interface than NumPy 1.

### Tasks

NumPy 2.0 was released for testing so that libraries could ensure compatibility [since mid-March](https://github.com/numpy/numpy/issues/24300#issuecomment-1986815755).  What needs to be done for HuggingFace to support Numpy 2?

- [x] Fix use of `array`: https://github.com/huggingface/datasets/pull/6976
- [ ] Remove [NumPy version limit](https://github.com/huggingface/datasets/pull/6975): https://github.com/huggingface/datasets/pull/6991

Comments:
IndexError during training with Squad dataset and T5-small model

### Describe the bug

I am encountering an IndexError while training a T5-small model on the Squad dataset using the transformers and datasets libraries. The error occurs even with a minimal reproducible example, suggesting a potential bug or incompatibility.

### Steps to reproduce the bug

1.Install the required libraries: !pip install transformers datasets
2.Run the following code:
!pip install transformers datasets

import torch
from transformers import AutoTokenizer, AutoModelForSeq2SeqLM, TrainingArguments, Trainer, DataCollatorWithPadding

# Load a small, publicly available dataset
from datasets import load_dataset
dataset = load_dataset("squad", split="train[:100]") # Use a small subset for testing

# Load a pre-trained model and tokenizer
model_name = "t5-small"
tokenizer = AutoTokenizer.from_pretrained(model_name)
model = AutoModelForSeq2SeqLM.from_pretrained(model_name)

# Define a basic data collator
data_collator = DataCollatorWithPadding(tokenizer=tokenizer)

# Define training arguments
training_args = TrainingArguments(
    output_dir="./results",
    per_device_train_batch_size=2,
    num_train_epochs=1,
)

# Create a trainer
trainer = Trainer(
    model=model,
    args=training_args,
    train_dataset=dataset,
    data_collator=data_collator,
)

# Train the model
trainer.train()

### Expected behavior

---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
[<ipython-input-23-f13a4b23c001>](https://localhost:8080/#) in <cell line: 34>()
     32 
     33 # Train the model
---> 34 trainer.train()

10 frames
[/usr/local/lib/python3.10/dist-packages/datasets/formatting/formatting.py](https://localhost:8080/#) in _check_valid_index_key(key, size)
    427     if isinstance(key, int):
    428         if (key < 0 and key + size < 0) or (key >= size):
--> 429             raise IndexError(f"Invalid key: {key} is out of bounds for size {size}")
    430         return
    431     elif isinstance(key, slice):

IndexError: Invalid key: 42 is out of bounds for size 0

### Environment info

transformers version:4.41.2
datasets version:1.18.4
Python version:3.10.12


Comments:
add remove_unused_columns=False to training_args
https://github.com/huggingface/datasets/issues/6535#issuecomment-1874024704

Closing this issue because it was a reported and fixed in transformers.
Method to load Laion400m

### Feature request

Large datasets like Laion400m are provided as embeddings. The provided methods in load_dataset are not straightforward for loading embedding files, i.e. img_emb_XX.npy ; XX = 0 to 99


### Motivation

The trial and experimentation is the key pivot of HF. It would be great if HF can load embeddings files s,ealessly.

### Your contribution

I cam write the loader with some help.

Comments:
Manual downloads should count as downloads

### Feature request

I would like to request that manual downloads of data files from Hugging Face dataset repositories count as downloads of a dataset. According to the documentation for the Hugging Face Hub, that is currently not the case: https://huggingface.co/docs/hub/en/datasets-download-stats

### Motivation

This would ensure that downloads are accurately reported to end users.

### Your contribution

N/A

Comments:
We're unlikely to add more features/support for datasets with python loading scripts, which include datasets with manual download. Sorry for the inconvenience
My Private Dataset doesn't exist on the Hub or cannot be accessed

### Describe the bug


```
  File "/root/miniconda3/envs/gino_conda/lib/python3.9/site-packages/datasets/load.py", line 1852, in dataset_module_factory
    raise DatasetNotFoundError(msg + f" at revision '{revision}'" if revision else msg)
datasets.exceptions.DatasetNotFoundError: Dataset 'xxx' doesn't exist on the Hub or cannot be accessed
>>> dataset = load_dataset("xxxx", token=True)

404 error 404 Client Error. (Request ID: Root=xxxx)

Repository Not Found for url: https://huggingface.co/api/datasets/xxx/xxx.
Please make sure you specified the correct `repo_id` and `repo_type`.
If you are trying to access a private or gated repo, make sure you are authenticated.
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/root/miniconda3/envs/gino_conda/lib/python3.9/site-packages/datasets/load.py", line 2593, in load_dataset
    builder_instance = load_dataset_builder(
  File "/root/miniconda3/envs/gino_conda/lib/python3.9/site-packages/datasets/load.py", line 2265, in load_dataset_builder
    dataset_module = dataset_module_factory(
  File "/root/miniconda3/envs/gino_conda/lib/python3.9/site-packages/datasets/load.py", line 1910, in dataset_module_factory
    raise e1 from None
  File "/root/miniconda3/envs/gino_conda/lib/python3.9/site-packages/datasets/load.py", line 1852, in dataset_module_factory
    raise DatasetNotFoundError(msg + f" at revision '{revision}'" if revision else msg)
datasets.exceptions.DatasetNotFoundError: Dataset 'xxx' doesn't exist on the Hub or cannot be accessed
```

### Steps to reproduce the bug

123

### Expected behavior

123

### Environment info

123

Comments:
I can load public dataset, but for my private dataset it fails

https://huggingface.co/docs/datasets/upload_dataset

I have checked the API HTTP link. Repository Not Found for url: https://huggingface.co/api/datasets/xxx/xxx.

![image](https://github.com/huggingface/datasets/assets/39621324/4aceef59-0c65-4161-9665-676d25d73225)

It just works fine.

It seems that everything is in a mass huh....

![image](https://github.com/huggingface/datasets/assets/39621324/fb2fe12c-4f0a-4bf6-9656-63ba50347b10)


https://huggingface.co/datasets/rajpurkar/squad/blob/main/squad.py fails again

https://github.com/huggingface/datasets/blob/main/templates/new_dataset_script.py#L81 can not use this, too complex. I just need a def to load my file to a dict

I am facing the same issue. Did you find a fix?

You should authenticate to be able to access private or gated repos: https://huggingface.co/docs/hub/datasets-gated#access-gated-datasets-as-a-user
`Dataset.with_format` behaves inconsistently with documentation

### Describe the bug

The actual behavior of the interface `Dataset.with_format` is inconsistent with the documentation.
https://huggingface.co/docs/datasets/use_with_pytorch#n-dimensional-arrays
https://huggingface.co/docs/datasets/v2.19.0/en/use_with_tensorflow#n-dimensional-arrays

> If your dataset consists of N-dimensional arrays, you will see that by default they are considered as nested lists.
> In particular, a PyTorch formatted dataset outputs nested lists instead of a single tensor.
> A TensorFlow formatted dataset outputs a RaggedTensor instead of a single tensor.

But I get a single tensor by default, which is  inconsistent with the description.

Actually the current behavior seems more reasonable to me. Therefore, the document needs to be modified.

### Steps to reproduce the bug

```python
>>> from datasets import Dataset
>>> data = [[[1, 2],[3, 4]],[[5, 6],[7, 8]]]
>>> ds = Dataset.from_dict({"data": data})
>>> ds = ds.with_format("torch")
>>> ds[0]
{'data': tensor([[1, 2],
        [3, 4]])}
>>> ds = ds.with_format("tf")
>>> ds[0]
{'data': <tf.Tensor: shape=(2, 2), dtype=int64, numpy=
array([[1, 2],
       [3, 4]])>}
```

### Expected behavior

```python
>>> from datasets import Dataset
>>> data = [[[1, 2],[3, 4]],[[5, 6],[7, 8]]]
>>> ds = Dataset.from_dict({"data": data})
>>> ds = ds.with_format("torch")
>>> ds[0]
{'data': [tensor([1, 2]), tensor([3, 4])]}
>>> ds = ds.with_format("tf")
>>> ds[0]
{'data': <tf.RaggedTensor [[1, 2], [3, 4]]>}
```

### Environment info

datasets==2.19.1
torch==2.1.0
tensorflow==2.13.1

Comments:
Hi ! It seems the documentation was outdated in this paragraph

I fixed it here: https://github.com/huggingface/datasets/pull/6956

Fixed.
load_dataset error

### Describe the bug

Why does the program get stuck when I use load_dataset method, and it still gets stuck after loading for several hours? In fact, my json file is only 21m, and I can load it in one go using open('', 'r').

### Steps to reproduce the bug

1. pip install datasets==2.19.2
2. from datasets import Dataset, DatasetDict, NamedSplit, Split, load_dataset
3. data = load_dataset('json', data_files='train.json')

### Expected behavior

It is able to load my json correctly

### Environment info

datasets==2.19.2

Comments:
Hi, @lion-ops.

In our Continuous Integration we have many tests on loading JSON files and all of them work properly.

Could you please share your "train.json" file, so that we can try to reproduce the issue you have? 

> Hi, @lion-ops.
> 
> In our Continuous Integration we have many tests on loading JSON files and all of them work properly.
> 
> Could you please share your "train.json" file, so that we can try to reproduce the issue you have?

Thank you for your reply. I can load it normally in another server. Is it possible that the disk of my server is a network disk in the LAN, so it will be downloaded from the LAN and get stuck?
to_tf_dataset: Visible devices cannot be modified after being initialized

### Describe the bug

When trying to use to_tf_dataset with a custom data_loader collate_fn when I use parallelism I am met with the following error as many times as number of workers there were in ``num_workers``.

  File "/opt/miniconda/envs/env/lib/python3.11/site-packages/multiprocess/process.py", line 314, in _bootstrap
    self.run()
  File "/opt/miniconda/envs/env/lib/python3.11/site-packages/multiprocess/process.py", line 108, in run
    self._target(*self._args, **self._kwargs)
  File "/opt/miniconda/envs/env/lib/python3.11/site-packages/datasets/utils/tf_utils.py", line 438, in worker_loop
    tf.config.set_visible_devices([], "GPU")  # Make sure workers don't try to allocate GPU memory
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/miniconda/envs/env/lib/python3.11/site-packages/tensorflow/python/framework/config.py", line 566, in set_visible_devices
    context.context().set_visible_devices(devices, device_type)
  File "/opt/miniconda/envs/env/lib/python3.11/site-packages/tensorflow/python/eager/context.py", line 1737, in set_visible_devices
    raise RuntimeError(
RuntimeError: Visible devices cannot be modified after being initialized

### Steps to reproduce the bug

1. Download a dataset using HuggingFace load_dataset
2. Define a function that transforms the data in some way to be used in the collate_fn argument
3. Provide a ``batch_size`` and ``num_workers`` value in the ``to_tf_dataset`` function
4. Either retrieve directly or use tfds benchmark to test the dataset

``` python
from datasets import load_datasets
import tensorflow_datasets as tfds
from keras_cv.layers import Resizing

def data_loader(examples):
      x = Resizing(examples[0]['image'], 256, 256, crop_to_aspect_ratio=True)
      return {X[0]: x}

ds = load_datasets("logasja/FDF", split="test")

ds = ds.to_tf_dataset(collate_fn=data_loader, batch_size=16, num_workers=2)

tfds.benchmark(ds)
```

### Expected behavior

Use multiple processes to apply transformations from the collate_fn to the tf dataset on the CPU.

### Environment info

- `datasets` version: 2.19.1
- Platform: Linux-6.5.0-1023-oracle-x86_64-with-glibc2.35
- Python version: 3.11.8
- `huggingface_hub` version: 0.22.2
- PyArrow version: 15.0.2
- Pandas version: 2.2.1
- `fsspec` version: 2024.2.0

Comments:
Enable Sharding to Equal Sized Shards

### Feature request

Add an option when sharding a dataset to have all shards the same size. Will be good to provide both an option of duplication, and by truncation.

### Motivation

Currently the behavior of sharding is "If n % i == l, then the first l shards will have length (n // i) + 1, and the remaining shards will have length (n // i).". However, when using FSDP we want the shards to have the same size. This requires the user to manually handle this situation, but it will be nice if we had an option to shard the dataset into equally sized shards. 

### Your contribution

For now just a PR. I can also add code that does what is needed, but probably not efficient.
Shard to equal size by duplication:
```
remainder = len(dataset) % num_shards
num_missing_examples = num_shards - remainder
duplicated = dataset.select(list(range(num_missing_examples)))
dataset = concatenate_datasets([dataset, duplicated])
shard = dataset.shard(num_shards, shard_idx)
```
Or by truncation:
```
shard = dataset.shard(num_shards, shard_idx)
num_examples_per_shard = len(dataset) // num_shards
shard = shard.select(list(range(num_examples_per_shard)))
```

Comments:
ExpectedMoreSplits error when using data_dir

As reported by @regisss, an `ExpectedMoreSplits` error is raised when passing `data_dir`:
```python
from datasets import load_dataset

dataset = load_dataset(
    "lvwerra/stack-exchange-paired",
    split="train",
    cache_dir=None,
    data_dir="data/rl",
)
```
```
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.10/dist-packages/datasets/load.py", line 2609, in load_dataset
    builder_instance.download_and_prepare(
  File "/usr/local/lib/python3.10/dist-packages/datasets/builder.py", line 1027, in download_and_prepare
    self._download_and_prepare(
  File "/usr/local/lib/python3.10/dist-packages/datasets/builder.py", line 1140, in _download_and_prepare
    verify_splits(self.info.splits, split_dict)
  File "/usr/local/lib/python3.10/dist-packages/datasets/utils/info_utils.py", line 92, in verify_splits
    raise ExpectedMoreSplits(str(set(expected_splits) - set(recorded_splits)))
datasets.utils.info_utils.ExpectedMoreSplits: {'test'}
```

Comments:
Fix expected splits when passing data_files or dir

reported on slack:

The following code snippet gives an error with v2.19 but not with v2.18:
from datasets import load_dataset
```
dataset = load_dataset(
    "lvwerra/stack-exchange-paired",
    split="train",
    cache_dir=None,
    data_dir="data/rl",
)
```
and the error is:
```
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.10/dist-packages/datasets/load.py", line 2609, in load_dataset
    builder_instance.download_and_prepare(
  File "/usr/local/lib/python3.10/dist-packages/datasets/builder.py", line 1027, in download_and_prepare
    self._download_and_prepare(
  File "/usr/local/lib/python3.10/dist-packages/datasets/builder.py", line 1140, in _download_and_prepare
    verify_splits(self.info.splits, split_dict)
  File "/usr/local/lib/python3.10/dist-packages/datasets/utils/info_utils.py", line 92, in verify_splits
    raise ExpectedMoreSplits(str(set(expected_splits) - set(recorded_splits)))
datasets.utils.info_utils.ExpectedMoreSplits: {'test'}
```


Comments:
The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_6938). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

fix is included in https://github.com/huggingface/datasets/pull/6925
save_to_disk() freezes when saving on s3 bucket with multiprocessing

### Describe the bug

I'm trying to save a `Dataset` using the `save_to_disk()` function with:
- `num_proc > 1`
- `dataset_path` being a s3 bucket path e.g. "s3://{bucket_name}/{dataset_folder}/"

The hf progress bar shows up but the saving does not seem to start. 
When using one processor only (`num_proc=1`), everything works fine.
When saving the dataset on local disk (as opposed to s3 bucket) with `num_proc > 1`, everything works fine.

Thank you for your help! :)

### Steps to reproduce the bug

I tried without any storage options:

```
from datasets import load_dataset

sandbox_ds = load_dataset("openai_humaneval")
sandbox_ds["test"].save_to_disk(
    "s3://bucket-name/test_multiprocessing_saving/",
    num_proc=4,
)
```


and with the specific s3fs storage options: 
```
from datasets import load_dataset
from s3fs import S3FileSystem

def get_s3fs():
    return S3FileSystem()

sandbox_ds = load_dataset("openai_humaneval")
sandbox_ds["test"].save_to_disk(
    "s3://bucket-name/test_multiprocessing_saving/",
    num_proc=4,
    storage_options=get_s3fs().storage_options, # also tried: storage_options=S3FileSystem().storage_options
)
```

I'm guessing I might use `storage_options` parameter wrongly, but I didn't find anything online that made it work.

**NB**: Behavior is the same when trying to save the whole `DatasetDict`.

### Expected behavior

Progress bar fills in and saving is carried out.

### Environment info

`datasets==2.18.0`

Comments:
I got the same issue. Any updates so far for this issue?

Same here. Any updates?

+1, experiencing this as well
Support for pathlib.Path in datasets 2.19.0

### Describe the bug

After the recent update of `datasets`, Dataset.save_to_disk does not accept a pathlib.Path anymore. It was supported in 2.18.0 and previous versions. Is this intentional? Was it supported before only because of a Python dusk-typing miracle?

### Steps to reproduce the bug

```
from datasets import Dataset
import pathlib

path = pathlib.Path("./my_out_path")
Dataset.from_dict(
    {"text": ["hello world"], "label": [777], "split": ["train"]}
.save_to_disk(path)
```
This results in an error when using datasets 2.19:
```
Traceback (most recent call last):
  File "<stdin>", line 3, in <module>
  File "/Users/jb/scratch/venv/lib/python3.11/site-packages/datasets/arrow_dataset.py", line 1515, in save_to_disk
    fs, _ = url_to_fs(dataset_path, **(storage_options or {}))
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/jb/scratch/venv/lib/python3.11/site-packages/fsspec/core.py", line 383, in url_to_fs
    chain = _un_chain(url, kwargs)
            ^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/jb/scratch/venv/lib/python3.11/site-packages/fsspec/core.py", line 323, in _un_chain
    if "::" in path
       ^^^^^^^^^^^^
TypeError: argument of type 'PosixPath' is not iterable
```

Converting to str works, however.
```
Dataset.from_dict(
     {"text": ["hello world"], "label": [777], "split": ["train"]}
).save_to_disk(str(path))
```

### Expected behavior

My dataset gets saved to disk without an error.

### Environment info

aiohttp==3.9.5
aiosignal==1.3.1
attrs==23.2.0
certifi==2024.2.2
charset-normalizer==3.3.2
datasets==2.19.0
dill==0.3.8
filelock==3.14.0
frozenlist==1.4.1
fsspec==2024.3.1
huggingface-hub==0.23.2
idna==3.7
multidict==6.0.5
multiprocess==0.70.16
numpy==1.26.4
packaging==24.0
pandas==2.2.2
pyarrow==16.1.0
pyarrow-hotfix==0.6
python-dateutil==2.9.0.post0
pytz==2024.1
PyYAML==6.0.1
requests==2.32.3
six==1.16.0
tqdm==4.66.4
typing_extensions==4.12.0
tzdata==2024.1
urllib3==2.2.1
xxhash==3.4.1
yarl==1.9.4

Comments:
+1 I just noticed this when I tried to update `datasets` today.

The same issue, I also get error.
ValueError: Couldn't infer the same data file format for all splits. Got {'train': ('json', {}), 'validation': (None, {})}

### Describe the bug

When I run the code en = load_dataset("allenai/c4", "en", streaming=True), I encounter an error: raise ValueError(f"Couldn't infer the same data file format for all splits. Got {split_modules}") ValueError: Couldn't infer the same data file format for all splits. Got {'train': ('json', {}), 'validation': (None, {})}.
However, running dataset = load_dataset('allenai/c4', streaming=True, data_files={'validation': 'en/c4-validation.00003-of-00008.json.gz'}, split='validation') works fine. What is the issue here?

### Steps to reproduce the bug

run code：
import os
os.environ['HF_ENDPOINT'] = 'https://hf-mirror.com'
from datasets import load_dataset

en = load_dataset("allenai/c4", "en", streaming=True)

### Expected behavior

Successfully loaded the dataset.

### Environment info

- `datasets` version: 2.18.0
- Platform: Linux-6.5.0-28-generic-x86_64-with-glibc2.17
- Python version: 3.8.19
- `huggingface_hub` version: 0.22.2
- PyArrow version: 15.0.2
- Pandas version: 2.0.3
- `fsspec` version: 2024.2.0


Comments:
How do you solve it ?


> How do you solve it ?

Please check your Python environment and dataset version. I have just resolved the issue, which was caused by a Python environment switching error
Avoid downloading the whole dataset when only README.me has been touched on hub.

### Feature request

`datasets.load_dataset()` triggers a new download of the **whole dataset** when the README.md file has been touched on huggingface hub, even if data files / parquet files are the exact same.

I think the current behaviour of the load_dataset function is triggered whenever a change of the hash of latest commit on huggingface hub, but  is there a clever way to only download again the dataset **if and only if** data is modified ?  

### Motivation

The current behaviour is a waste of network bandwidth / disk space / research time.

### Your contribution

I don't have time to submit a PR, but I hope a simple solution will emerge from this issue ! 

Comments:
you're right, we're tackling this here: https://github.com/huggingface/dataset-viewer/issues/2757

@severo : great !
Caching map result of DatasetDict.

Hi!

I'm currenty using the map function to tokenize a somewhat large dataset, so I need to use the cache to save ~25 mins.

Changing num_proc incduces the recomputation of the map, I'm not sure why and if this is excepted behavior? 

here it says, that cached files are loaded sequentially:

https://github.com/huggingface/datasets/blob/bb2664cf540d5ce4b066365e7c8b26e7f1ca4743/src/datasets/arrow_dataset.py#L3005-L3006

it seems like I can pass in a fingerprint, and load it directly:

https://github.com/huggingface/datasets/blob/bb2664cf540d5ce4b066365e7c8b26e7f1ca4743/src/datasets/arrow_dataset.py#L3108-L3125

**Environment Setup:**

- Python 3.11.9
- datasets  2.19.1 conda-forge
- Linux 6.1.83-1.el9.elrepo.x86_64

**MRE**
```python
fixed raw_datasets
fixed tokenize_function

tokenized_datasets = raw_datasets.map(
                        tokenize_function,
                        batched=True,
                        num_proc=9,
                        remove_columns=['text'],
                        load_from_cache_file= True,
                        desc="Running tokenizer on dataset line_by_line",
                    )


tokenized_datasets = raw_datasets.map(
                        tokenize_function,
                        batched=True,
                        num_proc=5,
                        remove_columns=['text'],
                        load_from_cache_file= True,
                        desc="Running tokenizer on dataset line_by_line",
                    )
```

Comments:
Has to do with sharding as far as I am aware, num_proc splits the dataset in shards and each process picks up a shard.

@dimidagd why wouldn't you redistribute the processes (e.g. param_num_process to sequentially fill fingerprint_num_process) to make things work out? 

Perhaps I'm missing something important.

I assume data has to be split between the processes somehow, and the decision to split it to num_processes shards is very convenient :). As I understand, the idea behind individual shard caching is being able to recover part of the processing if one of the processes fails. It would make sense to do a hierarchical cache checking though, where irregardless of the amount of processes, there is a check on whether the entire .map result has been cached or not (basically num_proc=1). Downside is more disk space used to cache both the shards and the entire dataset.
Export Parquet Tablet Audio-Set is null bytes in Arrow 

### Describe the bug

Exporting the processed audio inside the table with the dataset.to_parquet function, the object pyarrow {bytes: null, path: "Some/Path"}
At the same time, the same dataset uploaded to the hub has bit arrays

![Screenshot from 2024-05-27 19-14-49](https://github.com/huggingface/datasets/assets/140120605/ddfba089-426f-4659-9df4-7a634c948b9e)
![Screenshot from 2024-05-27 19-12-51](https://github.com/huggingface/datasets/assets/140120605/4cf8c0a1-650e-491b-86c8-b475c284a021)


### Steps to reproduce the bug

1.Get dataset from audio and cast it 
2.Export and push dataset
3.It’s scary to be indignant at the difference in the uploaded dataset and the fact that it was saved locally
```py
from datasets import Dataset, Audio 
df = Dataset.from_csv("./datasets.csv")
df = df.cast_column("audio", Audio(16000))
df.to_parquet("./datasets.parquet")
df.push_to_hub(repo_id="************", token="**********************")
```

You can use "try replicate case" for this
[replicate_packet.zip](https://github.com/huggingface/datasets/files/15457114/replicate_packet.zip)


### Expected behavior

Two parquet tables identical in content. It is obvious?

### Environment info

Python 3.11+ (I try did it in 3.12 and got same result )

Comments:
Invalid YAML in README.md: unknown tag !<tag:yaml.org,2002:python/tuple>

### Describe the bug

I wrote a notebook to load an existing dataset, process it, and upload as a private dataset using `dataset.push_to_hub(...)` at the end. The push to hub is failing with:

```
ValueError: Invalid metadata in README.md.
- Invalid YAML in README.md: unknown tag !<tag:yaml.org,2002:python[/tuple](http://192.168.1.128:8888/tuple)> (50:11)

 47 |             - 4
 48 |             - 4
 49 |             - 8
 50 |           - !!binary |
----------------^
 51 |             TwAAAA==
 52 |           '1': !!python[/object/apply](http://192.168.1.128:8888/object/apply):nump ...
```

My dataset has a `train` and `validation` dataset.  These are the features:

```
{'c1': Value(dtype='string', id=None),
 'c2': Value(dtype='string', id=None),
 'c3': [{'value': Value(dtype='string', id=None),
   'start': Value(dtype='int64', id=None),
   'end': Value(dtype='int64', id=None),
   'label': Value(dtype='string', id=None)}],
 'c4': Value(dtype='string', id=None),
 'c5': Value(dtype='string', id=None),
 'c6': Value(dtype='string', id=None),
 'c7': Value(dtype='string', id=None),
 'c8': Sequence(feature=Value(dtype='int32', id=None), length=-1, id=None),
 'c9': Sequence(feature=Value(dtype='int8', id=None), length=-1, id=None),
 'c10': Sequence(feature=Value(dtype='int8', id=None), length=-1, id=None),
 'labels': Sequence(feature=ClassLabel(names=['O', 'B-ABC', 'I-ABC', ...], id=None), length=-1, id=None),
 'c12': Sequence(feature=Value(dtype='string', id=None), length=-1, id=None)}
```

This used to work until I decided to cast the `labels` feature to a `Sequence(ClassLabel(...))` type with:

```
ds['train'] = ds['train'].cast_column("labels", Sequence(ClassLabel(names=list(labels))))
ds['validation'] = ds['validation'].cast_column("labels", Sequence(ClassLabel(names=list(labels))))
```

### Steps to reproduce the bug

1. Start with any token classification dataset.
2. Add a `labels` column with data such as `[0,0,0,12,13,13,13,0,0]`.
3. Cast the label column from `Sequence` to `Sequence(ClassLabel))` with:

```
labels = ['O', 'B-TEST', 'I-TEST']
ds = ds.cast_column("labels", Sequence(ClassLabel(names=labels)))
```

4. Push to hub with `ds.push_to_hub("me/awesome-stuff-dataset")`

### Expected behavior

I expected `push_to_hub` to successfully push my dataset to the hub without error.

### Environment info

Python 3.11.9

datasets==2.19.1
transformers==4.41.1
PyYAML==6.0.1

Comments:
```push_to_hub()``` - Prevent Automatic Generation of Splits 

### Describe the bug

I currently have a dataset which has not been splited. When pushing the dataset to my hugging face dataset repository, it is split into a testing and training set. How can I prevent the split from happening?

### Steps to reproduce the bug

1. Have a unsplit dataset 

```python
Dataset({ features: ['input', 'output', 'Attack', '__index_level_0__'], num_rows: 944685 })
```

2. Push it to huggingface

```python
dataset.push_to_hub(dataset_name)
```

3. On the hugging face dataset repo, the dataset then appears to be splited:

![image](https://github.com/huggingface/datasets/assets/29337128/b4fbc141-42b0-4f49-98df-dd479648fe09)

4. Indeed, when loading the dataset from this repo, the dataset is split in two testing and training set.

```python
from datasets import load_dataset, Dataset

dataset = load_dataset("Jetlime/NF-CSE-CIC-IDS2018-v2", streaming=True)
dataset
```
output: 

```
IterableDatasetDict({
    train: IterableDataset({
        features: ['input', 'output', 'Attack', '__index_level_0__'],
        n_shards: 2
    })
    test: IterableDataset({
        features: ['input', 'output', 'Attack', '__index_level_0__'],
        n_shards: 1
    })
```

### Expected behavior

The dataset shall not be splited, as not requested.

### Environment info

- `datasets` version: 2.19.1
- Platform: Linux-6.2.0-35-generic-x86_64-with-glibc2.35
- Python version: 3.10.12
- `huggingface_hub` version: 0.23.0
- PyArrow version: 15.0.2
- Pandas version: 2.2.2
- `fsspec` version: 2024.3.1

Comments:
Column order is nondeterministic when loading from JSON

As reported by @meg-huggingface, the order of the JSON object keys is not preserved while loading a dataset from a JSON file with a list of objects.

For example, when loading a JSON files with a list of objects, each with the following ordered keys:
- [ID, Language, Topic], 

the resulting dataset may have columns:
- [ID, Topic, Language], or
- [Topic, Language, ID], or
- [Topic, ID, Language],...

This issue is caused by the use of a Python set (which does not preserve the order):
https://github.com/huggingface/datasets/blob/60d21efbc01e15d0b596ac1072750cbecd91548a/src/datasets/packaged_modules/json/json.py#L168
introduced in
- #5772

Comments:
Add MedImg for streaming

### Feature request

Host the MedImg dataset (similar to Imagenet but for biomedical images). 

### Motivation

There is a clear need for biomedical image foundation models and large scale biomedical datasets that are easily streamable. This would be an excellent tool for the biomedical community.

### Your contribution

MedImg can be found [here](https://www.cuilab.cn/medimg/#).

Comments:
@mariosasko, @lhoestq, @albertvillanova
Hello! Can anyone help? or can you guys suggest who can help with this?

Hi ! Feel free to download the dataset and create a `Dataset` object with it.

Then your'll be able to use `push_to_hub()` to upload the dataset to HF in Parquet format and make it streamable :)

> Hi ! Feel free to download the dataset and create a `Dataset` object with it.
> 
> Then your'll be able to use `push_to_hub()` to upload the dataset to HF in Parquet format and make it streamable :)

The dataset is several TB in total, which I do not have the resources to handle.

Hi @lhoestq and @albertvillanova , just following up about this.

for big datasets you can push_to_hub one part at a time (e.g. as different splits) and merge the parts (just a simple modification in the YAML part of the README)

Sure, that makes sense. However, isn't there a size limit to what typical users can push?

Yes there is a limit, simply let us know by email at datasets [at] huggingface.co - this way we can give you a storage grant also help making sure the dataset is all good for people to use it easily

> Yes there is a limit, simply let us know by email at datasets [at] huggingface.co - this way we can give you a storage grant also help making sure the dataset is all good for people to use it easily

Got it, that would be great.
Support the deserialization of json lines files comprised of lists

### Feature request

I manage a somewhat large and popular Hugging Face dataset known as the [Open Australian Legal Corpus](https://huggingface.co/datasets/umarbutler/open-australian-legal-corpus). I recently updated my corpus to be stored in a json lines file where each line is an array and each element represents a value at a particular column. Previously, my corpus was stored as a json lines file where each line was a dictionary and the keys were the fields.

Essentially, a line in my json lines file used to look like this:
```json
{"version_id":"","type":"","jurisdiction":"","source":"","citation":"","url":"","when_scraped":"","text":""}
```

And now it looks like this:
```json
["","","","","","","",""]
```

This saves 65 bytes per document and allows me very quickly serialise and deserialise documents via `msgspec`.

After making this change, I found that `datasets` was incapable of deserialising my Corpus without a custom loading script, even if I ensured that the `dataset_info` field in my dataset card contained the desired names of my features.

I would like to request that functionality be added to support this format which is more memory-efficent and faster than using dictionaries.

### Motivation

The [documentation](https://huggingface.co/docs/datasets/en/dataset_script) for creating dataset loading scripts asserts that:
> In the next major release, the new safety features of 🤗 Datasets will disable running dataset loading scripts by default, and you will have to pass trust_remote_code=True to load datasets that require running a dataset script.

I would rather not require my users to pass `trust_remote_code=True` which means that I will need built-in support for this format.

### Your contribution

I would be happy to submit a PR for this if this is something you would incorporate into `datasets` and if I can be pointed to where the code would need to go.

Comments:
Update: I ended up deciding to go back to use lines of dictionaries instead of arrays, not because of this issue as my users would be capable of downloading my corpus without `datasets`, but the speed and storage savings are not currently worth breaking my API and harming the backwards compatibility of each new revision.

With that said, for a static dataset that is not regularly updated like mine, and particularly for extremely large datasets with millions or billions of rows, using arrays could have a meaningful impact, and so there is probably still value in supporting this structure, provided the effort is not too much.
Extraction protocol for arrow files is not defined

### Describe the bug

Passing files with `.arrow` extension into data_files argument, at least when `streaming=True` is very slow.

### Steps to reproduce the bug

 Basically it goes through the `_get_extraction_protocol` method located [here](https://github.com/huggingface/datasets/blob/main/src/datasets/utils/file_utils.py#L820)
The method then looks at some base known extensions where `arrow` is not defined so it proceeds to determine the compression with the magic number method which is slow when dealing with a lot of files which are stored in s3 and by looking at this predefined list, I don't see `arrow` in there either so in the end it return None:

```
MAGIC_NUMBER_TO_COMPRESSION_PROTOCOL = {
    bytes.fromhex("504B0304"): "zip",
    bytes.fromhex("504B0506"): "zip",  # empty archive
    bytes.fromhex("504B0708"): "zip",  # spanned archive
    bytes.fromhex("425A68"): "bz2",
    bytes.fromhex("1F8B"): "gzip",
    bytes.fromhex("FD377A585A00"): "xz",
    bytes.fromhex("04224D18"): "lz4",
    bytes.fromhex("28B52FFD"): "zstd",
}
```

### Expected behavior

My expectation is that `arrow` would be in the known lists so it would return None without going through the magic number method.

### Environment info

datasets 2.19.0

Comments:
Fixed in https://github.com/huggingface/datasets/pull/7083