def test_small_bitmap(self):
"""
Tests initializing with a bitmap that is too small
(e.g. less than or equal to the extra_buffer() size)
"""
with pytest.raises(ValueError):
pyBloom(Bitmap(pyBloom.extra_buffer()), 3)
def test_params_for_capacity(self):
"""
Tests that the parameters that are generated for a given
capacity and probability are correct given known sane values.
"""
# From http://hur.st/bloomfilter?n=1e6&p=1e-4
bytes, k = pyBloom.params_for_capacity(1e6, 1e-4)
assert bytes - pyBloom.extra_buffer() == round(19170117 / 8.0)
assert k == 14 # Parameters uses the ceiling instead of rounding
def test_for_capacity(self):
"""
Tests that the for_capacity method makes a sane bloom filter
using parameters that are generated for a given
capacity and probability are correct given known sane values.
"""
# From http://hur.st/bloomfilter?n=1e6&p=1e-4
bf = pyBloom.for_capacity(1e6, 1e-4)
# Check the bitmap size
assert (len(bf.bitmap) / 8) - pyBloom.extra_buffer() == round(19170117 / 8.0)
# Check the k num
assert bf.k_num == 14 # Parameters uses the ceiling instead of rounding
