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 = cBloom.params_for_capacity(1e6, 1e-4)
assert bytes - cBloom.extra_buffer() == round(19170117 / 8.0)
assert k == 14 # Parameters uses the ceiling instead of rounding
def test_swap(self):
"""
Swaps the mmap files from one implementation to another,
check that things work. Start with cBloom, then pyBloom.
"""
bytes, k = cBloom.params_for_capacity(2e4, 1e-3)
bitmap = Bitmap(bytes, "testswap1.mmap")
bf1 = cBloom(bitmap, k)
[bf1.add("foo%d" % x) for x in xrange(20000)]
bf1.close()
# Make a new bitmap
bitmap = Bitmap(bytes, "testswap1.mmap")
bf2 = pyBloom(bitmap, 50)
assert len(bf2) == 20000 # Should reload size and k
assert bf2.k_num == k
# Check all the entries
assert all([bf2.__contains__("foo%d" % x) for x in xrange(20000)])
bf2.close()
def test_equality_2(self):
"""
Tests that the two implementation generate matching mmaps
"""
bytes, k = cBloom.params_for_capacity(2e4, 1e-3)
bitmap = Bitmap(bytes, "testcompatc2.mmap")
bf1 = cBloom(bitmap, k)
[bf1.add("foo%d" % x) for x in xrange(20000)]
# Make a new bitmap
bitmap = Bitmap(bytes, "testcompatpy2.mmap")
bf2 = pyBloom(bitmap, k)
[bf2.add("foo%d" % x) for x in xrange(20000)]
# Check the lengths
assert len(bf1) == len(bf2)
bf1.close()
bf2.close()
# Compare the mmap files
self.compare_files("testcompatc2.mmap", "testcompatpy2.mmap")
