import pytest
from itertools import count
import sys
import os
sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))
from slic.utils.xrange import *


def is_count_iterator(obj):
    return isinstance(obj, type(count()))

@pytest.mark.parametrize("args, kwargs, expected", [
    ((10,), {}, list(range(10))),                      # xrange(10)
    ((0, 10), {}, list(range(0, 10))),                 # xrange(0, 10)
    ((0, 10, 2), {}, list(range(0, 10, 2))),           # xrange(0, 10, 2)
    ((10,), {"step": 2}, list(range(0, 10, 2))),       # xrange(10, step=2)
])
def test_xrange_finite(args, kwargs, expected):
    assert list(xrange(*args, **kwargs)) == expected

@pytest.mark.parametrize("args, kwargs, expected_repr", [
    ((), {}, repr(count(0))),                          # xrange()
    ((), {"step": 2}, repr(count(0, 2))),              # xrange(step=2)
])
def test_xrange_infinite(args, kwargs, expected_repr):
    # Only test first few elements to avoid infinite loop
    result = xrange(*args, **kwargs)
    assert is_count_iterator(result)
    for i, val in zip(range(20), result):
        assert val == i * kwargs.get("step", 1)

@pytest.mark.parametrize("args", [
    (1, 2, 3, 4),  # too many positional arguments
])
def test_xrange_too_many_args(args):
    with pytest.raises(TypeError, match="xrange takes from 2 to 3 positional arguments"):
        xrange(*args)