예제 #1
0
 def setUp(self):
     super().setUp()
     # Height must be above the checkpoint, because the AuxPoW branch
     # doesn't verify PoW below the checkpoint.
     self.header = deserialize_pure_header(
         bfh(self.valid_header),
         constants.net.max_checkpoint() + 100)
예제 #2
0
    def test_deserialize_auxpow_header_explicit_coinbase(self):
        header = self.deserialize_with_auxpow(header_with_mm)
        header_auxpow = header['powdata']['auxpow']

        coinbase_tx = header_auxpow['parent_coinbase_tx']
        expected_coinbase_txid = 'e751249a0dfc33c119c2f3375054a8cfe18eacf8291da689cb8f4570afbdb1a3'
        observed_coinbase_txid = auxpow.fast_txid(coinbase_tx)

        self.assertEqual(expected_coinbase_txid, observed_coinbase_txid)

        self.assertEqual(header_auxpow['coinbase_merkle_branch'], [
            "5c3158d4f108917fba77f9695650608477456b8f6f06238b1613311aafa74b09",
            "eebaf1b6b9ab455497e6dd571140f0a3647ce36e1ab3e34a177dacc474a755d9",
            "b57660b84bf4011d416c6a884c329b092ad0fb0dabce075ed2a830ca14f86cb9",
            "2f8974fd4f4a648613dbed7544bbfcbbeceaa4c143aaed7812c14cbdb5cd3954",
            "26fe65cbf0e306f589fe74179b0d8e58ec664971ff8d3d10702803bb0f0a2cbf",
            "f280de3cf6d62a9b88713435a0319763df2886128a65ddb1af5d9b3ea01d4c07",
            "52a27c19db70842beba5d65be16d7eb04a9562762859bfb192f9fe65ac5bc8fa",
            "48ee3a89e348e962228292d9169a650323d0dc16b8c5e3ab84b98d94a2f8a466",
            "e2d47a5fa5522849202c0d2caa2906c13f8c44e1878420e4d8e8e892ea96097a",
            "a644bcb70473e2670f047d34da5cb3b6b886949cefee927706c4bf512e1ea73e",
            "676ac4c906bb6a5da87b20e0d6baf3b3bac55299556ec9e81e81e67bbd719b91",
            "04b4353b08ffd77e01d57285cbb2f538950d0039995889c685bcdd9c9c181870",
        ])

        coinbase_merkle_index = header_auxpow['coinbase_merkle_index']
        self.assertEqual(0, coinbase_merkle_index)

        self.assertEqual(header_auxpow['chain_merkle_branch'], [
            "2cadbb3ce34769fc6f95572012c22605f8c3a69982a9a6854523f6548007d30b",
            "e5c2407ba454ffeb28cf0c50c5c293a84c9a75788f8a8f35ccb974e606280377",
            "a5cd51355bea0fd77416d06bf3647e16b4663d2f87e6a3ccb23e713cb8b4de1c",
        ])

        chain_merkle_index = header_auxpow['chain_merkle_index']
        self.assertEqual(7, chain_merkle_index)

        expected_parent_header = blockchain.deserialize_pure_header(
            bfh('0000ff3f913d01444f14db2c6ab43ffd0f36af5613423815543c22000000000000000000ef6330ff500ba8a2eb0d2e988d3275057fcf81beb55e430e5cdf4a20dee82ad76c83785ba70d2c1728f397b0'
                ), None)

        expected_parent_hash = blockchain.hash_header(expected_parent_header)
        observed_parent_hash = blockchain.hash_header(
            header_auxpow['parent_header'])
        self.assertEqual(expected_parent_hash, observed_parent_hash)

        expected_parent_merkle_root = expected_parent_header['merkle_root']
        observed_parent_merkle_root = header_auxpow['parent_header'][
            'merkle_root']
        self.assertEqual(expected_parent_merkle_root,
                         observed_parent_merkle_root)
예제 #3
0
    def test_deserialize_auxpow_header_explicit_coinbase(self):
        header = self.deserialize_with_auxpow(namecoin_header_37174)
        header_auxpow = header['auxpow']

        self.assertEqual(constants.net.AUXPOW_CHAIN_ID,
                         header_auxpow['chain_id'])

        coinbase_tx = header_auxpow['parent_coinbase_tx']
        expected_coinbase_txid = '8a3164be45a621f85318647d425fe9f45837b8e42ec4fdd902d7f64daf61ff4a'
        observed_coinbase_txid = auxpow.fast_txid(coinbase_tx)

        self.assertEqual(expected_coinbase_txid, observed_coinbase_txid)

        self.assertEqual(header_auxpow['coinbase_merkle_branch'], [
            "f8f27314022a5165ae122642babb28dd44191dd36f99dad80b4f16b75197dde0",
            "c8a9dc420e17dee7b04bc0174c7a37ed9e5bc3f0ea0fdfe0b5d24bfc19ecedb0",
            "0ce9c5b98e212527e4aa7b9298435dc4e8f4dfc4dc63b7c89c06300637c33620",
            "3b6d0c4122a5b047cb879a440461839f0446f6bd451f01c6f0b14b6624e84136",
            "458500be38a68b215112df5e52d9c08fdd52034fb2005ce15d2a42be28e436cb",
        ])

        coinbase_merkle_index = header_auxpow['coinbase_merkle_index']
        self.assertEqual(0, coinbase_merkle_index)

        self.assertEqual(header_auxpow['chain_merkle_branch'], [
            "000000000000000000000000000000000000000000000000000000000000000a",
            "65bd8eb2c7e3a3646507977e8659e5396b197f197fbb51e7158927a263798302",
            "5f961bb13289d705abb28376a01f7097535c95f87b9e719b9ec39d8eb20d72e9",
            "7cb5fdcc41120d6135a40a6753bddc0c9b675ba2936d2e0cd78cdcb02e6beb50",
        ])

        chain_merkle_index = header_auxpow['chain_merkle_index']
        self.assertEqual(11, chain_merkle_index)

        expected_parent_header = blockchain.deserialize_pure_header(
            bfh('0100000055a7bc918827dbe7d8027781d803f4b418589b7b9fc03e718a03000000000000625a3d6dc4dfb0ab25f450cd202ff3bdb074f2edde1ddb4af5217e10c9dbafb9639a0a4fd7690d1a25aeaa97'
                ), None)

        expected_parent_hash = blockchain.hash_header(expected_parent_header)
        observed_parent_hash = blockchain.hash_header(
            header_auxpow['parent_header'])
        self.assertEqual(expected_parent_hash, observed_parent_hash)

        expected_parent_merkle_root = expected_parent_header['merkle_root']
        observed_parent_merkle_root = header_auxpow['parent_header'][
            'merkle_root']
        self.assertEqual(expected_parent_merkle_root,
                         observed_parent_merkle_root)
예제 #4
0
class TestBlockchain(SequentialTestCase):

    HEADERS = {
        'A': deserialize_pure_header(bfh("0100000000000000000000000000000000000000000000000000000000000000000000003ba3edfd7a7b12b27ac72c3e67768f617fc81bc3888a51323a9fb8aa4b1e5e4adae5494dffff7f2002000000"), 0),
        'B': deserialize_pure_header(bfh("0000002006226e46111a0b59caaf126043eb5bbf28c34f3a5e332a1fc7b2b73cf188910f186c8dfd970a4545f79916bc1d75c9d00432f57c89209bf3bb115b7612848f509c25f45bffff7f2000000000"), 1),
        'C': deserialize_pure_header(bfh("00000020686bdfc6a3db73d5d93e8c9663a720a26ecb1ef20eb05af11b36cdbc57c19f7ebf2cbf153013a1c54abaf70e95198fcef2f3059cc6b4d0f7e876808e7d24d11cc825f45bffff7f2000000000"), 2),
        'D': deserialize_pure_header(bfh("00000020122baa14f3ef54985ae546d1611559e3f487bd2a0f46e8dbb52fbacc9e237972e71019d7feecd9b8596eca9a67032c5f4641b23b5d731dc393e37de7f9c2f299e725f45bffff7f2000000000"), 3),
        'E': deserialize_pure_header(bfh("00000020f8016f7ef3a17d557afe05d4ea7ab6bde1b2247b7643896c1b63d43a1598b747a3586da94c71753f27c075f57f44faf913c31177a0957bbda42e7699e3a2141aed25f45bffff7f2001000000"), 4),
        'F': deserialize_pure_header(bfh("000000201d589c6643c1d121d73b0573e5ee58ab575b8fdf16d507e7e915c5fbfbbfd05e7aee1d692d1615c3bdf52c291032144ce9e3b258a473c17c745047f3431ff8e2ee25f45bffff7f2000000000"), 5),
        'O': deserialize_pure_header(bfh("00000020b833ed46eea01d4c980f59feee44a66aa1162748b6801029565d1466790c405c3a141ce635cbb1cd2b3a4fcdd0a3380517845ba41736c82a79cab535d31128066526f45bffff7f2001000000"), 6),
        'P': deserialize_pure_header(bfh("00000020abe8e119d1877c9dc0dc502d1a253fb9a67967c57732d2f71ee0280e8381ff0a9690c2fe7c1a4450c74dc908fe94dd96c3b0637d51475e9e06a78e944a0c7fe28126f45bffff7f2000000000"), 7),
        'Q': deserialize_pure_header(bfh("000000202ce41d94eb70e1518bc1f72523f84a903f9705d967481e324876e1f8cf4d3452148be228a4c3f2061bafe7efdfc4a8d5a94759464b9b5c619994d45dfcaf49e1a126f45bffff7f2000000000"), 8),
        'R': deserialize_pure_header(bfh("00000020552755b6c59f3d51e361d16281842a4e166007799665b5daed86a063dd89857415681cb2d00ff889193f6a68a93f5096aeb2d84ca0af6185a462555822552221a626f45bffff7f2000000000"), 9),
        'S': deserialize_pure_header(bfh("00000020a13a491cbefc93cd1bb1938f19957e22a134faf14c7dee951c45533e2c750f239dc087fc977b06c24a69c682d1afd1020e6dc1f087571ccec66310a786e1548fab26f45bffff7f2000000000"), 10),
        'T': deserialize_pure_header(bfh("00000020dbf3a9b55dfefbaf8b6e43a89cf833fa2e208bbc0c1c5d76c0d71b9e4a65337803b243756c25053253aeda309604363460a3911015929e68705bd89dff6fe064b026f45bffff7f2002000000"), 11),
        'U': deserialize_pure_header(bfh("000000203d0932b3b0c78eccb39a595a28ae4a7c966388648d7783fd1305ec8d40d4fe5fd67cb902a7d807cee7676cb543feec3e053aa824d5dfb528d5b94f9760313d9db726f45bffff7f2001000000"), 12),
        'G': deserialize_pure_header(bfh("00000020b833ed46eea01d4c980f59feee44a66aa1162748b6801029565d1466790c405c3a141ce635cbb1cd2b3a4fcdd0a3380517845ba41736c82a79cab535d31128066928f45bffff7f2001000000"), 6),
        'H': deserialize_pure_header(bfh("00000020e19e687f6e7f83ca394c114144dbbbc4f3f9c9450f66331a125413702a2e1a719690c2fe7c1a4450c74dc908fe94dd96c3b0637d51475e9e06a78e944a0c7fe26a28f45bffff7f2002000000"), 7),
        'I': deserialize_pure_header(bfh("0000002009dcb3b158293c89d7cf7ceeb513add122ebc3880a850f47afbb2747f5e48c54148be228a4c3f2061bafe7efdfc4a8d5a94759464b9b5c619994d45dfcaf49e16a28f45bffff7f2000000000"), 8),
        'J': deserialize_pure_header(bfh("000000206a65f3bdd3374a5a6c4538008ba0b0a560b8566291f9ef4280ab877627a1742815681cb2d00ff889193f6a68a93f5096aeb2d84ca0af6185a462555822552221c928f45bffff7f2000000000"), 9),
        'K': deserialize_pure_header(bfh("00000020bb3b421653548991998f96f8ba486b652fdb07ca16e9cee30ece033547cd1a6e9dc087fc977b06c24a69c682d1afd1020e6dc1f087571ccec66310a786e1548fca28f45bffff7f2000000000"), 10),
        'L': deserialize_pure_header(bfh("00000020c391d74d37c24a130f4bf4737932bdf9e206dd4fad22860ec5408978eb55d46303b243756c25053253aeda309604363460a3911015929e68705bd89dff6fe064ca28f45bffff7f2000000000"), 11),
        'M': deserialize_pure_header(bfh("000000206a65f3bdd3374a5a6c4538008ba0b0a560b8566291f9ef4280ab877627a1742815681cb2d00ff889193f6a68a93f5096aeb2d84ca0af6185a4625558225522214229f45bffff7f2000000000"), 9),
        'N': deserialize_pure_header(bfh("00000020383dab38b57f98aa9b4f0d5ff868bc674b4828d76766bf048296f4c45fff680a9dc087fc977b06c24a69c682d1afd1020e6dc1f087571ccec66310a786e1548f4329f45bffff7f2003000000"), 10),
        'X': deserialize_pure_header(bfh("0000002067f1857f54b7fef732cb4940f7d1b339472b3514660711a820330fd09d8fba6b03b243756c25053253aeda309604363460a3911015929e68705bd89dff6fe0649b29f45bffff7f2002000000"), 11),
        'Y': deserialize_pure_header(bfh("00000020db33c9768a9e5f7c37d0f09aad88d48165946c87d08f7d63793f07b5c08c527fd67cb902a7d807cee7676cb543feec3e053aa824d5dfb528d5b94f9760313d9d9b29f45bffff7f2000000000"), 12),
        'Z': deserialize_pure_header(bfh("0000002047822b67940e337fda38be6f13390b3596e4dea2549250256879722073824e7f0f2596c29203f8a0f71ae94193092dc8f113be3dbee4579f1e649fa3d6dcc38c622ef45bffff7f2003000000"), 13),
    }
    # tree of headers:
    #                                            - M <- N <- X <- Y <- Z
    #                                          /
    #                             - G <- H <- I <- J <- K <- L
    #                           /
    # A <- B <- C <- D <- E <- F <- O <- P <- Q <- R <- S <- T <- U

    @classmethod
    def setUpClass(cls):
        super().setUpClass()
        constants.set_regtest()

    @classmethod
    def tearDownClass(cls):
        super().tearDownClass()
        constants.set_mainnet()

    def setUp(self):
        super().setUp()
        self.data_dir = tempfile.mkdtemp()
        make_dir(os.path.join(self.data_dir, 'forks'))
        self.config = SimpleConfig({'electrum_path': self.data_dir})
        blockchain.blockchains = {}

    def tearDown(self):
        super().tearDown()
        shutil.rmtree(self.data_dir)

    def _append_header(self, chain: Blockchain, header: dict):
        self.assertTrue(chain.can_connect(header))
        chain.save_header(header)

    def test_get_height_of_last_common_block_with_chain(self):
        blockchain.blockchains[constants.net.GENESIS] = chain_u = Blockchain(
            config=self.config, forkpoint=0, parent=None,
            forkpoint_hash=constants.net.GENESIS, prev_hash=None)
        open(chain_u.path(), 'w+').close()
        self._append_header(chain_u, self.HEADERS['A'])
        self._append_header(chain_u, self.HEADERS['B'])
        self._append_header(chain_u, self.HEADERS['C'])
        self._append_header(chain_u, self.HEADERS['D'])
        self._append_header(chain_u, self.HEADERS['E'])
        self._append_header(chain_u, self.HEADERS['F'])
        self._append_header(chain_u, self.HEADERS['O'])
        self._append_header(chain_u, self.HEADERS['P'])
        self._append_header(chain_u, self.HEADERS['Q'])

        chain_l = chain_u.fork(self.HEADERS['G'])
        self._append_header(chain_l, self.HEADERS['H'])
        self._append_header(chain_l, self.HEADERS['I'])
        self._append_header(chain_l, self.HEADERS['J'])
        self._append_header(chain_l, self.HEADERS['K'])
        self._append_header(chain_l, self.HEADERS['L'])

        self.assertEqual({chain_u:  8, chain_l: 5}, chain_u.get_parent_heights())
        self.assertEqual({chain_l: 11},             chain_l.get_parent_heights())

        chain_z = chain_l.fork(self.HEADERS['M'])
        self._append_header(chain_z, self.HEADERS['N'])
        self._append_header(chain_z, self.HEADERS['X'])
        self._append_header(chain_z, self.HEADERS['Y'])
        self._append_header(chain_z, self.HEADERS['Z'])

        self.assertEqual({chain_u:  8, chain_z: 5}, chain_u.get_parent_heights())
        self.assertEqual({chain_l: 11, chain_z: 8}, chain_l.get_parent_heights())
        self.assertEqual({chain_z: 13},             chain_z.get_parent_heights())
        self.assertEqual(5, chain_u.get_height_of_last_common_block_with_chain(chain_l))
        self.assertEqual(5, chain_l.get_height_of_last_common_block_with_chain(chain_u))
        self.assertEqual(5, chain_u.get_height_of_last_common_block_with_chain(chain_z))
        self.assertEqual(5, chain_z.get_height_of_last_common_block_with_chain(chain_u))
        self.assertEqual(8, chain_l.get_height_of_last_common_block_with_chain(chain_z))
        self.assertEqual(8, chain_z.get_height_of_last_common_block_with_chain(chain_l))

        self._append_header(chain_u, self.HEADERS['R'])
        self._append_header(chain_u, self.HEADERS['S'])
        self._append_header(chain_u, self.HEADERS['T'])
        self._append_header(chain_u, self.HEADERS['U'])

        self.assertEqual({chain_u: 12, chain_z: 5}, chain_u.get_parent_heights())
        self.assertEqual({chain_l: 11, chain_z: 8}, chain_l.get_parent_heights())
        self.assertEqual({chain_z: 13},             chain_z.get_parent_heights())
        self.assertEqual(5, chain_u.get_height_of_last_common_block_with_chain(chain_l))
        self.assertEqual(5, chain_l.get_height_of_last_common_block_with_chain(chain_u))
        self.assertEqual(5, chain_u.get_height_of_last_common_block_with_chain(chain_z))
        self.assertEqual(5, chain_z.get_height_of_last_common_block_with_chain(chain_u))
        self.assertEqual(8, chain_l.get_height_of_last_common_block_with_chain(chain_z))
        self.assertEqual(8, chain_z.get_height_of_last_common_block_with_chain(chain_l))

    def test_parents_after_forking(self):
        blockchain.blockchains[constants.net.GENESIS] = chain_u = Blockchain(
            config=self.config, forkpoint=0, parent=None,
            forkpoint_hash=constants.net.GENESIS, prev_hash=None)
        open(chain_u.path(), 'w+').close()
        self._append_header(chain_u, self.HEADERS['A'])
        self._append_header(chain_u, self.HEADERS['B'])
        self._append_header(chain_u, self.HEADERS['C'])
        self._append_header(chain_u, self.HEADERS['D'])
        self._append_header(chain_u, self.HEADERS['E'])
        self._append_header(chain_u, self.HEADERS['F'])
        self._append_header(chain_u, self.HEADERS['O'])
        self._append_header(chain_u, self.HEADERS['P'])
        self._append_header(chain_u, self.HEADERS['Q'])

        self.assertEqual(None, chain_u.parent)

        chain_l = chain_u.fork(self.HEADERS['G'])
        self._append_header(chain_l, self.HEADERS['H'])
        self._append_header(chain_l, self.HEADERS['I'])
        self._append_header(chain_l, self.HEADERS['J'])
        self._append_header(chain_l, self.HEADERS['K'])
        self._append_header(chain_l, self.HEADERS['L'])

        self.assertEqual(None,    chain_l.parent)
        self.assertEqual(chain_l, chain_u.parent)

        chain_z = chain_l.fork(self.HEADERS['M'])
        self._append_header(chain_z, self.HEADERS['N'])
        self._append_header(chain_z, self.HEADERS['X'])
        self._append_header(chain_z, self.HEADERS['Y'])
        self._append_header(chain_z, self.HEADERS['Z'])

        self.assertEqual(chain_z, chain_u.parent)
        self.assertEqual(chain_z, chain_l.parent)
        self.assertEqual(None,    chain_z.parent)

        self._append_header(chain_u, self.HEADERS['R'])
        self._append_header(chain_u, self.HEADERS['S'])
        self._append_header(chain_u, self.HEADERS['T'])
        self._append_header(chain_u, self.HEADERS['U'])

        self.assertEqual(chain_z, chain_u.parent)
        self.assertEqual(chain_z, chain_l.parent)
        self.assertEqual(None,    chain_z.parent)

    def test_forking_and_swapping(self):
        blockchain.blockchains[constants.net.GENESIS] = chain_u = Blockchain(
            config=self.config, forkpoint=0, parent=None,
            forkpoint_hash=constants.net.GENESIS, prev_hash=None)
        open(chain_u.path(), 'w+').close()

        self._append_header(chain_u, self.HEADERS['A'])
        self._append_header(chain_u, self.HEADERS['B'])
        self._append_header(chain_u, self.HEADERS['C'])
        self._append_header(chain_u, self.HEADERS['D'])
        self._append_header(chain_u, self.HEADERS['E'])
        self._append_header(chain_u, self.HEADERS['F'])
        self._append_header(chain_u, self.HEADERS['O'])
        self._append_header(chain_u, self.HEADERS['P'])
        self._append_header(chain_u, self.HEADERS['Q'])
        self._append_header(chain_u, self.HEADERS['R'])

        chain_l = chain_u.fork(self.HEADERS['G'])
        self._append_header(chain_l, self.HEADERS['H'])
        self._append_header(chain_l, self.HEADERS['I'])
        self._append_header(chain_l, self.HEADERS['J'])

        # do checks
        self.assertEqual(2, len(blockchain.blockchains))
        self.assertEqual(1, len(os.listdir(os.path.join(self.data_dir, "forks"))))
        self.assertEqual(0, chain_u.forkpoint)
        self.assertEqual(None, chain_u.parent)
        self.assertEqual(constants.net.GENESIS, chain_u._forkpoint_hash)
        self.assertEqual(None, chain_u._prev_hash)
        self.assertEqual(os.path.join(self.data_dir, "blockchain_headers"), chain_u.path())
        self.assertEqual(10 * 80, os.stat(chain_u.path()).st_size)
        self.assertEqual(6, chain_l.forkpoint)
        self.assertEqual(chain_u, chain_l.parent)
        self.assertEqual(hash_header(self.HEADERS['G']), chain_l._forkpoint_hash)
        self.assertEqual(hash_header(self.HEADERS['F']), chain_l._prev_hash)
        self.assertEqual(os.path.join(self.data_dir, "forks", "fork2_6_5c400c7966145d56291080b6482716a16aa644eefe590f984c1da0ee46ed33b8_711a2e2a701354121a33660f45c9f9f3c4bbdb4441114c39ca837f6e7f689ee1"), chain_l.path())
        self.assertEqual(4 * 80, os.stat(chain_l.path()).st_size)

        self._append_header(chain_l, self.HEADERS['K'])

        # chains were swapped, do checks
        self.assertEqual(2, len(blockchain.blockchains))
        self.assertEqual(1, len(os.listdir(os.path.join(self.data_dir, "forks"))))
        self.assertEqual(6, chain_u.forkpoint)
        self.assertEqual(chain_l, chain_u.parent)
        self.assertEqual(hash_header(self.HEADERS['O']), chain_u._forkpoint_hash)
        self.assertEqual(hash_header(self.HEADERS['F']), chain_u._prev_hash)
        self.assertEqual(os.path.join(self.data_dir, "forks", "fork2_6_5c400c7966145d56291080b6482716a16aa644eefe590f984c1da0ee46ed33b8_aff81830e28e01ef7d23277c56779a6b93f251a2d50dcc09d7c87d119e1e8ab"), chain_u.path())
        self.assertEqual(4 * 80, os.stat(chain_u.path()).st_size)
        self.assertEqual(0, chain_l.forkpoint)
        self.assertEqual(None, chain_l.parent)
        self.assertEqual(constants.net.GENESIS, chain_l._forkpoint_hash)
        self.assertEqual(None, chain_l._prev_hash)
        self.assertEqual(os.path.join(self.data_dir, "blockchain_headers"), chain_l.path())
        self.assertEqual(11 * 80, os.stat(chain_l.path()).st_size)
        for b in (chain_u, chain_l):
            self.assertTrue(all([b.can_connect(b.read_header(i), False) for i in range(b.height())]))

        self._append_header(chain_u, self.HEADERS['S'])
        self._append_header(chain_u, self.HEADERS['T'])
        self._append_header(chain_u, self.HEADERS['U'])
        self._append_header(chain_l, self.HEADERS['L'])

        chain_z = chain_l.fork(self.HEADERS['M'])
        self._append_header(chain_z, self.HEADERS['N'])
        self._append_header(chain_z, self.HEADERS['X'])
        self._append_header(chain_z, self.HEADERS['Y'])
        self._append_header(chain_z, self.HEADERS['Z'])

        # chain_z became best chain, do checks
        self.assertEqual(3, len(blockchain.blockchains))
        self.assertEqual(2, len(os.listdir(os.path.join(self.data_dir, "forks"))))
        self.assertEqual(0, chain_z.forkpoint)
        self.assertEqual(None, chain_z.parent)
        self.assertEqual(constants.net.GENESIS, chain_z._forkpoint_hash)
        self.assertEqual(None, chain_z._prev_hash)
        self.assertEqual(os.path.join(self.data_dir, "blockchain_headers"), chain_z.path())
        self.assertEqual(14 * 80, os.stat(chain_z.path()).st_size)
        self.assertEqual(9, chain_l.forkpoint)
        self.assertEqual(chain_z, chain_l.parent)
        self.assertEqual(hash_header(self.HEADERS['J']), chain_l._forkpoint_hash)
        self.assertEqual(hash_header(self.HEADERS['I']), chain_l._prev_hash)
        self.assertEqual(os.path.join(self.data_dir, "forks", "fork2_9_2874a1277687ab8042eff9916256b860a5b0a08b0038456c5a4a37d3bdf3656a_6e1acd473503ce0ee3cee916ca07db2f656b48baf8968f999189545316423bbb"), chain_l.path())
        self.assertEqual(3 * 80, os.stat(chain_l.path()).st_size)
        self.assertEqual(6, chain_u.forkpoint)
        self.assertEqual(chain_z, chain_u.parent)
        self.assertEqual(hash_header(self.HEADERS['O']), chain_u._forkpoint_hash)
        self.assertEqual(hash_header(self.HEADERS['F']), chain_u._prev_hash)
        self.assertEqual(os.path.join(self.data_dir, "forks", "fork2_6_5c400c7966145d56291080b6482716a16aa644eefe590f984c1da0ee46ed33b8_aff81830e28e01ef7d23277c56779a6b93f251a2d50dcc09d7c87d119e1e8ab"), chain_u.path())
        self.assertEqual(7 * 80, os.stat(chain_u.path()).st_size)
        for b in (chain_u, chain_l, chain_z):
            self.assertTrue(all([b.can_connect(b.read_header(i), False) for i in range(b.height())]))

        self.assertEqual(constants.net.GENESIS, chain_z.get_hash(0))
        self.assertEqual(hash_header(self.HEADERS['F']), chain_z.get_hash(5))
        self.assertEqual(hash_header(self.HEADERS['G']), chain_z.get_hash(6))
        self.assertEqual(hash_header(self.HEADERS['I']), chain_z.get_hash(8))
        self.assertEqual(hash_header(self.HEADERS['M']), chain_z.get_hash(9))
        self.assertEqual(hash_header(self.HEADERS['Z']), chain_z.get_hash(13))

    def test_doing_multiple_swaps_after_single_new_header(self):
        blockchain.blockchains[constants.net.GENESIS] = chain_u = Blockchain(
            config=self.config, forkpoint=0, parent=None,
            forkpoint_hash=constants.net.GENESIS, prev_hash=None)
        open(chain_u.path(), 'w+').close()

        self._append_header(chain_u, self.HEADERS['A'])
        self._append_header(chain_u, self.HEADERS['B'])
        self._append_header(chain_u, self.HEADERS['C'])
        self._append_header(chain_u, self.HEADERS['D'])
        self._append_header(chain_u, self.HEADERS['E'])
        self._append_header(chain_u, self.HEADERS['F'])
        self._append_header(chain_u, self.HEADERS['O'])
        self._append_header(chain_u, self.HEADERS['P'])
        self._append_header(chain_u, self.HEADERS['Q'])
        self._append_header(chain_u, self.HEADERS['R'])
        self._append_header(chain_u, self.HEADERS['S'])

        self.assertEqual(1, len(blockchain.blockchains))
        self.assertEqual(0, len(os.listdir(os.path.join(self.data_dir, "forks"))))

        chain_l = chain_u.fork(self.HEADERS['G'])
        self._append_header(chain_l, self.HEADERS['H'])
        self._append_header(chain_l, self.HEADERS['I'])
        self._append_header(chain_l, self.HEADERS['J'])
        self._append_header(chain_l, self.HEADERS['K'])
        # now chain_u is best chain, but it's tied with chain_l

        self.assertEqual(2, len(blockchain.blockchains))
        self.assertEqual(1, len(os.listdir(os.path.join(self.data_dir, "forks"))))

        chain_z = chain_l.fork(self.HEADERS['M'])
        self._append_header(chain_z, self.HEADERS['N'])
        self._append_header(chain_z, self.HEADERS['X'])

        self.assertEqual(3, len(blockchain.blockchains))
        self.assertEqual(2, len(os.listdir(os.path.join(self.data_dir, "forks"))))

        # chain_z became best chain, do checks
        self.assertEqual(0, chain_z.forkpoint)
        self.assertEqual(None, chain_z.parent)
        self.assertEqual(constants.net.GENESIS, chain_z._forkpoint_hash)
        self.assertEqual(None, chain_z._prev_hash)
        self.assertEqual(os.path.join(self.data_dir, "blockchain_headers"), chain_z.path())
        self.assertEqual(12 * 80, os.stat(chain_z.path()).st_size)
        self.assertEqual(9, chain_l.forkpoint)
        self.assertEqual(chain_z, chain_l.parent)
        self.assertEqual(hash_header(self.HEADERS['J']), chain_l._forkpoint_hash)
        self.assertEqual(hash_header(self.HEADERS['I']), chain_l._prev_hash)
        self.assertEqual(os.path.join(self.data_dir, "forks", "fork2_9_2874a1277687ab8042eff9916256b860a5b0a08b0038456c5a4a37d3bdf3656a_6e1acd473503ce0ee3cee916ca07db2f656b48baf8968f999189545316423bbb"), chain_l.path())
        self.assertEqual(2 * 80, os.stat(chain_l.path()).st_size)
        self.assertEqual(6, chain_u.forkpoint)
        self.assertEqual(chain_z, chain_u.parent)
        self.assertEqual(hash_header(self.HEADERS['O']), chain_u._forkpoint_hash)
        self.assertEqual(hash_header(self.HEADERS['F']), chain_u._prev_hash)
        self.assertEqual(os.path.join(self.data_dir, "forks", "fork2_6_5c400c7966145d56291080b6482716a16aa644eefe590f984c1da0ee46ed33b8_aff81830e28e01ef7d23277c56779a6b93f251a2d50dcc09d7c87d119e1e8ab"), chain_u.path())
        self.assertEqual(5 * 80, os.stat(chain_u.path()).st_size)

        self.assertEqual(constants.net.GENESIS, chain_z.get_hash(0))
        self.assertEqual(hash_header(self.HEADERS['F']), chain_z.get_hash(5))
        self.assertEqual(hash_header(self.HEADERS['G']), chain_z.get_hash(6))
        self.assertEqual(hash_header(self.HEADERS['I']), chain_z.get_hash(8))
        self.assertEqual(hash_header(self.HEADERS['M']), chain_z.get_hash(9))
        self.assertEqual(hash_header(self.HEADERS['X']), chain_z.get_hash(11))

        for b in (chain_u, chain_l, chain_z):
            self.assertTrue(all([b.can_connect(b.read_header(i), False) for i in range(b.height())]))