tbitcoin.py: make int_to_hex throw on overflow - electrum - Electrum Bitcoin wallet
HTML git clone https://git.parazyd.org/electrum
DIR Log
DIR Files
DIR Refs
DIR Submodules
---
DIR commit 1a8e8bc047bc6cd124b338e9c69c3bbb561db54a
DIR parent 79f4a8bae970b8581dc069934d7ae6a390c79c90
HTML Author: SomberNight <somber.night@protonmail.com>
Date: Sat, 16 Jun 2018 02:34:27 +0200
bitcoin.py: make int_to_hex throw on overflow
Diffstat:
M lib/bitcoin.py | 10 ++++++++--
M lib/tests/test_bitcoin.py | 22 +++++++++++++++++++++-
2 files changed, 29 insertions(+), 3 deletions(-)
---
DIR diff --git a/lib/bitcoin.py b/lib/bitcoin.py
t@@ -50,12 +50,18 @@ def rev_hex(s):
return bh2u(bfh(s)[::-1])
-def int_to_hex(i, length=1):
+def int_to_hex(i: int, length: int=1) -> str:
+ """Converts int to little-endian hex string.
+ `length` is the number of bytes available
+ """
if not isinstance(i, int):
raise TypeError('{} instead of int'.format(i))
+ range_size = pow(256, length)
+ if i < -range_size/2 or i >= range_size:
+ raise OverflowError('cannot convert int {} to hex ({} bytes)'.format(i, length))
if i < 0:
# two's complement
- i = pow(256, length) + i
+ i = range_size + i
s = hex(i)[2:].rstrip('L')
s = "0"*(2*length - len(s)) + s
return rev_hex(s)
DIR diff --git a/lib/tests/test_bitcoin.py b/lib/tests/test_bitcoin.py
t@@ -12,7 +12,7 @@ from lib.bitcoin import (
deserialize_privkey, serialize_privkey, is_segwit_address,
is_b58_address, address_to_scripthash, is_minikey, is_compressed, is_xpub,
xpub_type, is_xprv, is_bip32_derivation, seed_type, EncodeBase58Check,
- script_num_to_hex, push_script, add_number_to_script)
+ script_num_to_hex, push_script, add_number_to_script, int_to_hex)
from lib import ecc, crypto, ecc_fast
from lib.ecc import number_to_string, string_to_number
from lib.transaction import opcodes
t@@ -227,6 +227,26 @@ class Test_bitcoin(SequentialTestCase):
result = Hash(payload)
self.assertEqual(expected, result)
+ def test_int_to_hex(self):
+ self.assertEqual('00', int_to_hex(0, 1))
+ self.assertEqual('ff', int_to_hex(-1, 1))
+ self.assertEqual('00000000', int_to_hex(0, 4))
+ self.assertEqual('01000000', int_to_hex(1, 4))
+ self.assertEqual('7f', int_to_hex(127, 1))
+ self.assertEqual('7f00', int_to_hex(127, 2))
+ self.assertEqual('80', int_to_hex(128, 1))
+ self.assertEqual('80', int_to_hex(-128, 1))
+ self.assertEqual('8000', int_to_hex(128, 2))
+ self.assertEqual('ff', int_to_hex(255, 1))
+ self.assertEqual('ff7f', int_to_hex(32767, 2))
+ self.assertEqual('0080', int_to_hex(-32768, 2))
+ self.assertEqual('ffff', int_to_hex(65535, 2))
+ with self.assertRaises(OverflowError): int_to_hex(256, 1)
+ with self.assertRaises(OverflowError): int_to_hex(-129, 1)
+ with self.assertRaises(OverflowError): int_to_hex(-257, 1)
+ with self.assertRaises(OverflowError): int_to_hex(65536, 2)
+ with self.assertRaises(OverflowError): int_to_hex(-32769, 2)
+
def test_var_int(self):
for i in range(0xfd):
self.assertEqual(var_int(i), "{:02x}".format(i) )