from datasets import load_dataset


def test_streaming_dataset():
    dataset = load_dataset("./ccmatrix.py", "nl-en", streaming=True)
    assert list(dataset.keys()) == ["train"]

    train_ds = dataset["train"]

    i = iter(train_ds)
    e = next(i)

    assert e == {
        "id": 0,
        "score": 1.2499677,
        "translation": {
            "nl": "Zij kwamen uit alle delen van Egypte, evenals zij op de dag van Zijn komst zullen doen.",
            "en": "They come from all parts of Egypt, just like they will at the day of His coming.",
        },
    }

    e = next(i)

    assert list(e.keys()) == ["id", "score", "translation"]

    assert e == {
        "id": 1,
        "score": 1.2498379,
        "translation": {
            "nl": "En we moeten elke waarheid vals noemen die niet minstens door een lach vergezeld ging.”",
            "en": 'And we should call every truth false which was not accompanied by at least one laugh."',
        },
    }


def test_streaming_dataset_2():
    dataset = load_dataset("./ccmatrix.py", "nl-en", streaming=True)
    assert list(dataset.keys()) == ["train"]

    train_ds = dataset["train"]

    i = iter(train_ds)
    e = next(i)

    assert e == {
        "id": 0,
        "score": 1.2499677,
        "translation": {
            "nl": "Zij kwamen uit alle delen van Egypte, evenals zij op de dag van Zijn komst zullen doen.",
            "en": "They come from all parts of Egypt, just like they will at the day of His coming.",
        },
    }

    e = next(i)

    assert list(e.keys()) == ["id", "score", "translation"]

    assert e == {
        "id": 1,
        "score": 1.2498379,
        "translation": {
            "nl": "En we moeten elke waarheid vals noemen die niet minstens door een lach vergezeld ging.”",
            "en": 'And we should call every truth false which was not accompanied by at least one laugh."',
        },
    }


def test_max_train_samples_1():
    dataset = load_dataset("./ccmatrix.py", "nl-en", max_train_samples=123)
    assert list(dataset.keys()) == ["train"]

    train_ds = dataset["train"]
    assert len(train_ds) == 123

    i = iter(train_ds)
    e = next(i)

    assert e == {
        "id": 0,
        "score": 1.2499676942825317,
        "translation": {
            "nl": "Zij kwamen uit alle delen van Egypte, evenals zij op de dag van Zijn komst zullen doen.",
            "en": "They come from all parts of Egypt, just like they will at the day of His coming.",
        },
    }

    e = next(i)

    assert list(e.keys()) == ["id", "score", "translation"]

    assert e == {
        "id": 1,
        "score": 1.249837875366211,
        "translation": {
            "nl": "En we moeten elke waarheid vals noemen die niet minstens door een lach vergezeld ging.”",
            "en": 'And we should call every truth false which was not accompanied by at least one laugh."',
        },
    }


def test_max_train_samples_2():
    dataset = load_dataset("./ccmatrix.py", "nl-en", max_train_samples=256)
    assert list(dataset.keys()) == ["train"]

    train_ds = dataset["train"]
    assert len(train_ds) == 256

    i = iter(train_ds)
    e = next(i)