test: refactor: remove hex_str_to_bytes helper

Use the built-in class method bytes.fromhex() instead,
which is available since Python 3.0.

test/functional/test_framework/address.py

@@ -12,7 +12,7 @@ import unittest
 
 from .script import hash256, hash160, sha256, CScript, OP_0
 from .segwit_addr import encode_segwit_address
-from .util import assert_equal, hex_str_to_bytes
+from .util import assert_equal
 
 ADDRESS_BCRT1_UNSPENDABLE = 'bcrt1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq3xueyj'
 ADDRESS_BCRT1_UNSPENDABLE_DESCRIPTOR = 'addr(bcrt1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq3xueyj)#juyq9d97'
@@ -33,7 +33,7 @@ def byte_to_base58(b, version):
     result = ''
     str = b.hex()
     str = chr(version).encode('latin-1').hex() + str
-    checksum = hash256(hex_str_to_bytes(str)).hex()
+    checksum = hash256(bytes.fromhex(str)).hex()
     str += checksum[:8]
     value = int('0x' + str, 0)
     while value > 0:
@@ -100,7 +100,7 @@ def key_to_p2sh_p2wpkh(key, main=False):
 
 def program_to_witness(version, program, main=False):
     if (type(program) is str):
-        program = hex_str_to_bytes(program)
+        program = bytes.fromhex(program)
     assert 0 <= version <= 16
     assert 2 <= len(program) <= 40
     assert version > 0 or len(program) in [20, 32]
@@ -121,14 +121,14 @@ def script_to_p2sh_p2wsh(script, main=False):
 
 def check_key(key):
     if (type(key) is str):
-        key = hex_str_to_bytes(key)  # Assuming this is hex string
+        key = bytes.fromhex(key)  # Assuming this is hex string
     if (type(key) is bytes and (len(key) == 33 or len(key) == 65)):
         return key
     assert False
 
 def check_script(script):
     if (type(script) is str):
-        script = hex_str_to_bytes(script)  # Assuming this is hex string
+        script = bytes.fromhex(script)  # Assuming this is hex string
     if (type(script) is bytes or type(script) is CScript):
         return script
     assert False

test/functional/test_framework/blocktools.py

@@ -24,7 +24,6 @@ from .messages import (
     CTxInWitness,
     CTxOut,
     hash256,
-    hex_str_to_bytes,
     ser_uint256,
     tx_from_hex,
     uint256_from_str,
@@ -214,7 +213,7 @@ def witness_script(use_p2wsh, pubkey):
         pkscript = key_to_p2wpkh_script(pubkey)
     else:
         # 1-of-1 multisig
-        witness_script = CScript([OP_1, hex_str_to_bytes(pubkey), OP_1, OP_CHECKMULTISIG])
+        witness_script = CScript([OP_1, bytes.fromhex(pubkey), OP_1, OP_CHECKMULTISIG])
         pkscript = script_to_p2wsh_script(witness_script)
     return pkscript.hex()
 
@@ -223,7 +222,7 @@ def create_witness_tx(node, use_p2wsh, utxo, pubkey, encode_p2sh, amount):
 
     Optionally wrap the segwit output using P2SH."""
     if use_p2wsh:
-        program = CScript([OP_1, hex_str_to_bytes(pubkey), OP_1, OP_CHECKMULTISIG])
+        program = CScript([OP_1, bytes.fromhex(pubkey), OP_1, OP_CHECKMULTISIG])
         addr = script_to_p2sh_p2wsh(program) if encode_p2sh else script_to_p2wsh(program)
     else:
         addr = key_to_p2sh_p2wpkh(pubkey) if encode_p2sh else key_to_p2wpkh(pubkey)
@@ -246,7 +245,7 @@ def send_to_witness(use_p2wsh, node, utxo, pubkey, encode_p2sh, amount, sign=Tru
     else:
         if (insert_redeem_script):
             tx = tx_from_hex(tx_to_witness)
-            tx.vin[0].scriptSig += CScript([hex_str_to_bytes(insert_redeem_script)])
+            tx.vin[0].scriptSig += CScript([bytes.fromhex(insert_redeem_script)])
             tx_to_witness = tx.serialize().hex()
 
     return node.sendrawtransaction(tx_to_witness)

test/functional/test_framework/messages.py

@@ -30,7 +30,7 @@ import struct
 import time
 
 from test_framework.siphash import siphash256
-from test_framework.util import hex_str_to_bytes, assert_equal
+from test_framework.util import assert_equal
 
 MAX_LOCATOR_SZ = 101
 MAX_BLOCK_BASE_SIZE = 1000000
@@ -197,7 +197,7 @@ def from_hex(obj, hex_string):
     Note that there is no complementary helper like e.g. `to_hex` for the
     inverse operation. To serialize a message object to a hex string, simply
     use obj.serialize().hex()"""
-    obj.deserialize(BytesIO(hex_str_to_bytes(hex_string)))
+    obj.deserialize(BytesIO(bytes.fromhex(hex_string)))
     return obj
 
 

test/functional/test_framework/script_util.py

@@ -4,7 +4,6 @@
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Useful Script constants and utils."""
 from test_framework.script import CScript, hash160, sha256, OP_0, OP_DUP, OP_HASH160, OP_CHECKSIG, OP_EQUAL, OP_EQUALVERIFY
-from test_framework.util import hex_str_to_bytes
 
 # To prevent a "tx-size-small" policy rule error, a transaction has to have a
 # non-witness size of at least 82 bytes (MIN_STANDARD_TX_NONWITNESS_SIZE in
@@ -49,7 +48,7 @@ def key_to_p2sh_p2wpkh_script(key, main = False):
 
 def program_to_witness_script(version, program, main = False):
     if isinstance(program, str):
-        program = hex_str_to_bytes(program)
+        program = bytes.fromhex(program)
     assert 0 <= version <= 16
     assert 2 <= len(program) <= 40
     assert version > 0 or len(program) in [20, 32]
@@ -70,14 +69,14 @@ def script_to_p2sh_p2wsh_script(script, main = False):
 
 def check_key(key):
     if isinstance(key, str):
-        key = hex_str_to_bytes(key) # Assuming this is hex string
+        key = bytes.fromhex(key) # Assuming this is hex string
     if isinstance(key, bytes) and (len(key) == 33 or len(key) == 65):
         return key
     assert False
 
 def check_script(script):
     if isinstance(script, str):
-        script = hex_str_to_bytes(script) # Assuming this is hex string
+        script = bytes.fromhex(script) # Assuming this is hex string
     if isinstance(script, bytes) or isinstance(script, CScript):
         return script
     assert False

test/functional/test_framework/util.py

@@ -5,7 +5,6 @@
 """Helpful routines for regression testing."""
 
 from base64 import b64encode
-from binascii import unhexlify
 from decimal import Decimal, ROUND_DOWN
 from subprocess import CalledProcessError
 import hashlib
@@ -214,10 +213,6 @@ def count_bytes(hex_string):
     return len(bytearray.fromhex(hex_string))
 
 
-def hex_str_to_bytes(hex_str):
-    return unhexlify(hex_str.encode('ascii'))
-
-
 def str_to_b64str(string):
     return b64encode(string.encode('utf-8')).decode('ascii')
 
@@ -517,7 +512,7 @@ def gen_return_txouts():
     from .messages import CTxOut
     txout = CTxOut()
     txout.nValue = 0
-    txout.scriptPubKey = hex_str_to_bytes(script_pubkey)
+    txout.scriptPubKey = bytes.fromhex(script_pubkey)
     for _ in range(128):
         txouts.append(txout)
     return txouts

test/functional/test_framework/wallet.py

@@ -27,7 +27,6 @@ from test_framework.script import (
 )
 from test_framework.util import (
     assert_equal,
-    hex_str_to_bytes,
     satoshi_round,
 )
 
@@ -73,7 +72,7 @@ class MiniWallet:
             self._scriptPubKey = bytes(CScript([pub_key.get_bytes(), OP_CHECKSIG]))
         elif mode == MiniWalletMode.ADDRESS_OP_TRUE:
             self._address = ADDRESS_BCRT1_P2WSH_OP_TRUE
-            self._scriptPubKey = hex_str_to_bytes(self._test_node.validateaddress(self._address)['scriptPubKey'])
+            self._scriptPubKey = bytes.fromhex(self._test_node.validateaddress(self._address)['scriptPubKey'])
 
     def scan_blocks(self, *, start=1, num):
         """Scan the blocks for self._address outputs and add them to self._utxos"""

test/functional/test_framework/wallet_util.py

@@ -27,7 +27,6 @@ from test_framework.script_util import (
     script_to_p2sh_script,
     script_to_p2wsh_script,
 )
-from test_framework.util import hex_str_to_bytes
 
 Key = namedtuple('Key', ['privkey',
                          'pubkey',
@@ -93,7 +92,7 @@ def get_multisig(node):
         addr = node.getaddressinfo(node.getnewaddress())
         addrs.append(addr['address'])
         pubkeys.append(addr['pubkey'])
-    script_code = CScript([OP_2] + [hex_str_to_bytes(pubkey) for pubkey in pubkeys] + [OP_3, OP_CHECKMULTISIG])
+    script_code = CScript([OP_2] + [bytes.fromhex(pubkey) for pubkey in pubkeys] + [OP_3, OP_CHECKMULTISIG])
     witness_script = script_to_p2wsh_script(script_code)
     return Multisig(privkeys=[node.dumpprivkey(addr) for addr in addrs],
                     pubkeys=pubkeys,