import pytest
from funcy import rcompose, chunks


def test_rcompose():
    f = rcompose(lambda x: x ** 2, str, lambda x: x * 2)
    assert f(3) == "99"


def test_chunk_iterable_exact_split():
    a, b = chunks(5, iter(range(10)))
    assert a == list(range(5))
    assert b == list(range(5, 10))


def test_chunk_iterable_no_split():
    a = next(chunks(10, iter(range(10))))
    assert a == list(range(10))


def test_chunk_iterable_last_partial():
    a, b, c, d = chunks(3, iter(range(10)))
    assert d == [9]


def test_chunk_iterable_empty():
    with pytest.raises(StopIteration):
        next(chunks(3, iter(range(0))))


def test_chunk_iterable_less_than_chunk_size_elements():
    assert next(chunks(5, iter(range(2)))) == [0, 1]