def test_init(self):
g = exercise.Generator()
self.assertEqual(g._counter, 0)
self.assertEqual(
g._key,
binascii.unhexlify(
'0000000000000000000000000000000000000000000000000000000000000000'
))
def test_generate_blocks(self):
g = exercise.Generator()
g.reseed(b'hello')
# Because the generator is deterministic, the first two blocks are the same as in `test_generate_one_block`
self.assertEqual(
g._generate_blocks(3),
binascii.unhexlify(
'178b0a056e064d1eb07238ea7402fcf583d8d7e8a9a073b5f1d93f601fdaca40cce9cac929606fd6506ff1f9b082702d'
))
def test_generate_one_block(self):
g = exercise.Generator()
g.reseed(b'hello')
self.assertEqual(
g._generate_blocks(1),
binascii.unhexlify('178b0a056e064d1eb07238ea7402fcf5'))
self.assertEqual(
g._generate_blocks(1),
binascii.unhexlify('83d8d7e8a9a073b5f1d93f601fdaca40'))
def test_generate_data(self):
g = exercise.Generator()
g.reseed(b'hello')
# The (beginning of) the first block, as seen in `test_generate_one_block`
self.assertEqual(g.generate_data(13),
binascii.unhexlify('178b0a056e064d1eb07238ea74'))
# After each call to `_generate_data`, a new key is generated, making this data different
# from the one from the second block in `test_generate_one_block`
self.assertEqual(g.generate_data(8),
binascii.unhexlify('8d6aa6fe3aeda893'))
def test_reseed(self):
# `reseed` increments the counter to mark the generator as seeded, and computes the new key by
# hashing the old key together with the seed.
g = exercise.Generator()
g.reseed(binascii.unhexlify('1234'))
self.assertEqual(g._counter, 1)
self.assertEqual(
g._key,
exercise.double_sha(
binascii.unhexlify(
'00000000000000000000000000000000000000000000000000000000000000001234'
)))
def test_generate_data_with_invalid_size(self):
g = exercise.Generator()
g.reseed(b'hello')
self.assertRaises(Exception, g.generate_data, -1)
self.assertRaises(Exception, g.generate_data, 16_777_216)
def test_generate_blocks_from_unseeded(self):
g = exercise.Generator()
self.assertRaises(Exception, g._generate_blocks, 1)