import codecs

from capa.features.extractors import helpers


def test_all_zeros():
    # Python 2: <str>
    # Python 3: <bytes>
    a = b'\x00\x00\x00\x00'
    b = codecs.decode('00000000', 'hex')
    c = b'\x01\x00\x00\x00'
    d = codecs.decode('01000000', 'hex')
    assert helpers.all_zeros(a) is True
    assert helpers.all_zeros(b) is True
    assert helpers.all_zeros(c) is False
    assert helpers.all_zeros(d) is False