import pytest
import numpy as np

from tianshou.data import Batch


def test_batch():
    batch = Batch(obs=[0], np=np.zeros([3, 4]))
    batch.obs = [1]
    assert batch.obs == [1]
    batch.append(batch)
    assert batch.obs == [1, 1]
    assert batch.np.shape == (6, 4)
    assert batch[0].obs == batch[1].obs
    with pytest.raises(IndexError):
        batch[2]
    batch.obs = np.arange(5)
    for i, b in enumerate(batch.split(1, shuffle=False)):
        assert b.obs == batch[i].obs
    print(batch)


def test_batch_over_batch():
    batch = Batch(a=[3, 4, 5], b=[4, 5, 6])
    batch2 = Batch(c=[6, 7, 8], b=batch)
    batch2.b.b[-1] = 0
    print(batch2)
    assert batch2.values()[-1] == batch2.c
    assert batch2[-1].b.b == 0


if __name__ == '__main__':
    test_batch()
    test_batch_over_batch()