def test_interleave_datasets(dataset: IterableDataset, probas, seed, expected_length):
d1 = dataset
d2 = dataset.map(lambda x: {"id+1": x["id"] + 1, **x})
d3 = dataset.with_format("python")
datasets = [d1, d2, d3]
merged_dataset = interleave_datasets(datasets, probabilities=probas, seed=seed)
# Check the examples iterable
assert isinstance(
merged_dataset._ex_iterable, (CyclingMultiSourcesExamplesIterable, RandomlyCyclingMultiSourcesExamplesIterable)
)
# Check that it is deterministic
if seed is not None:
merged_dataset2 = interleave_datasets([d1, d2, d3], probabilities=probas, seed=seed)
assert list(merged_dataset) == list(merged_dataset2)
# Check first example
if seed is not None:
rng = np.random.default_rng(seed)
i = next(iter(RandomlyCyclingMultiSourcesExamplesIterable._iter_random_indices(rng, len(datasets), p=probas)))
assert next(iter(merged_dataset)) == next(iter(datasets[i]))
else:
assert any(next(iter(merged_dataset)) == next(iter(dataset)) for dataset in datasets)
# Compute length it case it's random
if expected_length is None:
expected_length = 0
counts = [len(list(d)) for d in datasets]
rng = np.random.default_rng(seed)
for i in RandomlyCyclingMultiSourcesExamplesIterable._iter_random_indices(rng, len(datasets), p=probas):
if counts[i] == 0:
break
counts[i] -= 1
expected_length += 1
# Check length
assert len(list(merged_dataset)) == expected_length
def test_iterable_dataset_map(dataset: IterableDataset, generate_examples_fn):
func = lambda x: {"id+1": x["id"] + 1} # noqa: E731
mapped_dataset = dataset.map(func)
assert isinstance(mapped_dataset._ex_iterable, MappedExamplesIterable)
assert mapped_dataset._ex_iterable.function is func
assert mapped_dataset._ex_iterable.batched is False
assert next(iter(mapped_dataset)) == {**next(iter(dataset)), **func(next(iter(generate_examples_fn()))[1])}
def test_iterable_dataset_map_batched(dataset: IterableDataset, generate_examples_fn):
func = lambda x: {"id+1": [i + 1 for i in x["id"]]} # noqa: E731
batch_size = 3
dataset = dataset.map(func, batched=True, batch_size=batch_size)
assert isinstance(dataset._ex_iterable, MappedExamplesIterable)
assert dataset._ex_iterable.function is func
assert dataset._ex_iterable.batch_size == batch_size
assert next(iter(dataset)) == {"id": 0, "id+1": 1}
def test_iterable_dataset_map_complex_features(dataset: IterableDataset, generate_examples_fn):
# https://github.com/huggingface/datasets/issues/3505
ex_iterable = ExamplesIterable(generate_examples_fn, {"label": "positive"})
features = Features(
{
"id": Value("int64"),
"label": Value("string"),
}
)
dataset = IterableDataset(ex_iterable, info=DatasetInfo(features=features))
dataset = dataset.cast_column("label", ClassLabel(names=["negative", "positive"]))
dataset = dataset.map(lambda x: {"id+1": x["id"] + 1, **x})
assert isinstance(dataset._ex_iterable, MappedExamplesIterable)
features["label"] = ClassLabel(names=["negative", "positive"])
assert [{k: v for k, v in ex.items() if k != "id+1"} for ex in dataset] == [
features.encode_example(ex) for _, ex in ex_iterable
]