def test_cows_padded(self):
""" Tests that COWS works on a buffer that gets padded. """
array = self.__create_buffer(1023)
original = array[:]
# Stuff the array.
cows.cows_stuff(array)
self.__check_zero_free(array)
# Now try unstuffing it.
cows.cows_unstuff(array)
# We should get the original back, except for the overhead, which we don't
# care about.
self.assertSequenceEqual(original[2:], array[2:])
def test_cows_all_zeros(self):
""" Tests that COWS works on a buffer that's all zeros. """
array = bytearray([0, 0] * 512)
original = array[:]
# Stuff the array.
cows.cows_stuff(array)
self.__check_zero_free(array)
# The entire array should be filled with ones.
expected = bytearray([0, 1] * 512)
self.assertSequenceEqual(expected, array)
# Now try unstuffing it.
cows.cows_unstuff(array)
# We should get the original back, except for the overhead, which we don't
# care about.
self.assertSequenceEqual(original[2:], array[2:])
def test_cows_padded_no_zeros(self):
""" Tests that COWS works on a buffer with no zeros that gets padded. """
array = bytearray([1] * 1023)
original = array[:]
# Stuff the array.
cows.cows_stuff(array)
self.__check_zero_free(array)
# The array should be unchanged, aside from the overhead.
expected = bytearray([2, 0]) + original[2:]
self.assertSequenceEqual(expected, array)
# Now try unstuffing it.
cows.cows_unstuff(array)
# We should get the original back, except for the overhead, which we don't
# care about.
self.assertSequenceEqual(original[2:], array[2:])
def test_cows_padded_all_zeros(self):
""" Tests that COWS works on a zero buffer that gets padded. """
array = bytearray([0] * 1023)
original = array[:]
# Stuff the array.
cows.cows_stuff(array)
self.__check_zero_free(array)
# The entire array should be filled with ones, except for the last word.
# This should be 2, because we padded with a non-zero byte.
expected = bytearray([0, 1] * 510) + bytearray([0, 2, 0])
self.assertSequenceEqual(expected, array)
# Now try unstuffing it.
cows.cows_unstuff(array)
# We should get the original back, except for the overhead, which we don't
# care about.
self.assertSequenceEqual(original[2:], array[2:])