Remove attempted Python 2 compatibility

This hacky approach precludes Mypy type checking.

Python 2 is not supported any more, and Tox is not running
the test suite in this version either.

Author: ysangkok

bitcoin/__init__.py

@@ -9,7 +9,6 @@
 # propagated, or distributed except according to the terms contained in the
 # LICENSE file.
 
-from __future__ import absolute_import, division, print_function, unicode_literals
 
 import bitcoin.core
 

bitcoin/base58.py

@@ -12,15 +12,6 @@
 
 """Base58 encoding and decoding"""
 
-from __future__ import absolute_import, division, print_function, unicode_literals
-
-import sys
-_bchr = chr
-_bord = ord
-if sys.version > '3':
-    long = int
-    _bchr = lambda x: bytes([x])
-    _bord = lambda x: x
 
 import binascii
 
@@ -52,10 +43,7 @@ def encode(b):
     res = ''.join(res[::-1])
 
     # Encode leading zeros as base58 zeros
-    czero = b'\x00'
-    if sys.version > '3':
-        # In Python3 indexing a bytes returns numbers, not characters.
-        czero = 0
+    czero = 0
     pad = 0
     for c in b:
         if c == czero:
@@ -108,7 +96,7 @@ def __new__(cls, s):
         if check0 != check1:
             raise Base58ChecksumError('Checksum mismatch: expected %r, calculated %r' % (check0, check1))
 
-        return cls.from_bytes(data, _bord(verbyte[0]))
+        return cls.from_bytes(data, verbyte[0])
 
     def __init__(self, s):
         """Initialize from base58-encoded string
@@ -138,7 +126,7 @@ def to_bytes(self):
 
     def __str__(self):
         """Convert to string"""
-        vs = _bchr(self.nVersion) + self
+        vs = bytes([self.nVersion]) + self
         check = bitcoin.core.Hash(vs)[0:4]
         return encode(vs + check)
 

bitcoin/bech32.py

@@ -11,14 +11,6 @@
 
 """Bech32 encoding and decoding"""
 
-import sys
-_bchr = chr
-_bord = ord
-if sys.version > '3':
-    long = int
-    _bchr = lambda x: bytes([x])
-    _bord = lambda x: x
-
 from bitcoin.segwit_addr import encode, decode
 import bitcoin
 

bitcoin/bloom.py

@@ -11,10 +11,8 @@
 
 """Bloom filter support"""
 
-from __future__ import absolute_import, division, print_function, unicode_literals
 
 import struct
-import sys
 import math
 
 import bitcoin.core
@@ -56,16 +54,12 @@ def MurmurHash3(nHashSeed, vDataToHash):
     # tail
     k1 = 0
     j = (len(vDataToHash) // 4) * 4
-    bord = ord
-    if sys.version > '3':
-        # In Py3 indexing bytes returns numbers, not characters
-        bord = lambda x: x
     if len(vDataToHash) & 3 >= 3:
-        k1 ^= bord(vDataToHash[j+2]) << 16
+        k1 ^= vDataToHash[j+2] << 16
     if len(vDataToHash) & 3 >= 2:
-        k1 ^= bord(vDataToHash[j+1]) << 8
+        k1 ^= vDataToHash[j+1] << 8
     if len(vDataToHash) & 3 >= 1:
-        k1 ^= bord(vDataToHash[j])
+        k1 ^= vDataToHash[j]
 
     k1 &= 0xFFFFFFFF
     k1 = (k1 * c1) & 0xFFFFFFFF
@@ -180,11 +174,7 @@ def stream_deserialize(cls, f):
         return deserialized
 
     def stream_serialize(self, f):
-        if sys.version > '3':
-            bitcoin.core.serialize.BytesSerializer.stream_serialize(self.vData, f)
-        else:
-            # 2.7 has problems with f.write(bytearray())
-            bitcoin.core.serialize.BytesSerializer.stream_serialize(bytes(self.vData), f)
+        bitcoin.core.serialize.BytesSerializer.stream_serialize(self.vData, f)
         f.write(self.__struct.pack(self.nHashFuncs, self.nTweak, self.nFlags))
 
 __all__ = (

bitcoin/core/__init__.py

@@ -9,28 +9,22 @@
 # propagated, or distributed except according to the terms contained in the
 # LICENSE file.
 
-from __future__ import absolute_import, division, print_function
 
 import binascii
 import struct
-import sys
 import time
 
-from .script import CScript, CScriptWitness, CScriptOp, OP_RETURN
+from . import script
+from .script import CScript, CScriptWitness, OP_RETURN
 
 from .serialize import *
 
-if sys.version > '3':
-    _bytes = bytes
-else:
-    _bytes = lambda x: bytes(bytearray(x))
-
 # Core definitions
 COIN = 100000000
 MAX_BLOCK_SIZE = 1000000
 MAX_BLOCK_WEIGHT = 4000000
 MAX_BLOCK_SIGOPS = MAX_BLOCK_SIZE/50
-WITNESS_COINBASE_SCRIPTPUBKEY_MAGIC = _bytes([OP_RETURN, 0x24, 0xaa, 0x21, 0xa9, 0xed])
+WITNESS_COINBASE_SCRIPTPUBKEY_MAGIC = bytes([OP_RETURN, 0x24, 0xaa, 0x21, 0xa9, 0xed])
 
 def MoneyRange(nValue, params=None):
     global coreparams
@@ -39,30 +33,14 @@ def MoneyRange(nValue, params=None):
 
     return 0 <= nValue <= params.MAX_MONEY
 
-def _py2_x(h):
-    """Convert a hex string to bytes"""
-    return binascii.unhexlify(h)
-
 def x(h):
     """Convert a hex string to bytes"""
     return binascii.unhexlify(h.encode('utf8'))
 
-def _py2_b2x(b):
-    """Convert bytes to a hex string"""
-    return binascii.hexlify(b)
-
 def b2x(b):
     """Convert bytes to a hex string"""
     return binascii.hexlify(b).decode('utf8')
 
-def _py2_lx(h):
-    """Convert a little-endian hex string to bytes
-
-    Lets you write uint256's and uint160's the way the Satoshi codebase shows
-    them.
-    """
-    return binascii.unhexlify(h)[::-1]
-
 def lx(h):
     """Convert a little-endian hex string to bytes
 
@@ -71,14 +49,6 @@ def lx(h):
     """
     return binascii.unhexlify(h.encode('utf8'))[::-1]
 
-def _py2_b2lx(b):
-    """Convert bytes to a little-endian hex string
-
-    Lets you show uint256's and uint160's the way the Satoshi codebase shows
-    them.
-    """
-    return binascii.hexlify(b[::-1])
-
 def b2lx(b):
     """Convert bytes to a little-endian hex string
 
@@ -87,18 +57,6 @@ def b2lx(b):
     """
     return binascii.hexlify(b[::-1]).decode('utf8')
 
-if not (sys.version > '3'):
-    x = _py2_x
-    b2x = _py2_b2x
-    lx = _py2_lx
-    b2lx = _py2_b2lx
-
-del _py2_x
-del _py2_b2x
-del _py2_lx
-del _py2_b2lx
-
-
 def str_money_value(value):
     """Convert an integer money value to a fixed point string"""
     r = '%i.%08i' % (value // COIN, value % COIN)

bitcoin/core/_bignum.py

@@ -13,7 +13,6 @@
 #
 # Internally used for script evaluation; not to be used externally.
 
-from __future__ import absolute_import, division, print_function, unicode_literals
 
 import struct
 

bitcoin/core/key.py

@@ -18,17 +18,10 @@
 import ctypes
 import ctypes.util
 import hashlib
-import sys
 from os import urandom
 import bitcoin
 import bitcoin.signature
 
-_bchr = chr
-_bord = ord
-if sys.version > '3':
-    _bchr = lambda x: bytes([x])
-    _bord = lambda x: x
-
 import bitcoin.core.script
 
 _ssl = ctypes.cdll.LoadLibrary(
@@ -587,8 +580,8 @@ def recover_compact(cls, hash, sig): # pylint: disable=redefined-builtin
         if len(sig) != 65:
             raise ValueError("Signature should be 65 characters, not [%d]" % (len(sig), ))
 
-        recid = (_bord(sig[0]) - 27) & 3
-        compressed = (_bord(sig[0]) - 27) & 4 != 0
+        recid = (sig[0] - 27) & 3
+        compressed = (sig[0] - 27) & 4 != 0
 
         cec_key = CECKey()
         cec_key.set_compressed(compressed)
@@ -620,12 +613,7 @@ def __str__(self):
         return repr(self)
 
     def __repr__(self):
-        # Always have represent as b'<secret>' so test cases don't have to
-        # change for py2/3
-        if sys.version > '3':
-            return '%s(%s)' % (self.__class__.__name__, super(CPubKey, self).__repr__())
-        else:
-            return '%s(b%s)' % (self.__class__.__name__, super(CPubKey, self).__repr__())
+        return '%s(%s)' % (self.__class__.__name__, super(CPubKey, self).__repr__())
 
 __all__ = (
         'CECKey',

bitcoin/core/script.py

@@ -15,18 +15,8 @@
 is in bitcoin.core.scripteval
 """
 
-from __future__ import absolute_import, division, print_function
-
-import sys
-_bchr = chr
-_bord = ord
-if sys.version > '3':
-    long = int
-    _bchr = lambda x: bytes([x])
-    _bord = lambda x: x
-    from io import BytesIO as _BytesIO
-else:
-    from cStringIO import StringIO as _BytesIO
+
+from io import BytesIO
 
 import struct
 
@@ -50,9 +40,9 @@ class CScriptOp(int):
     def encode_op_pushdata(d):
         """Encode a PUSHDATA op, returning bytes"""
         if len(d) < 0x4c:
-            return b'' + _bchr(len(d)) + d # OP_PUSHDATA
+            return bytes([len(d)]) + d # OP_PUSHDATA
         elif len(d) <= 0xff:
-            return b'\x4c' + _bchr(len(d)) + d # OP_PUSHDATA1
+            return b'\x4c' + bytes([len(d)]) + d # OP_PUSHDATA1
         elif len(d) <= 0xffff:
             return b'\x4d' + struct.pack(b'<H', len(d)) + d # OP_PUSHDATA2
         elif len(d) <= 0xffffffff:
@@ -524,12 +514,12 @@ class CScript(bytes):
     def __coerce_instance(cls, other):
         # Coerce other into bytes
         if isinstance(other, CScriptOp):
-            other = _bchr(other)
-        elif isinstance(other, (int, long)):
+            other = bytes([other])
+        elif isinstance(other, int):
             if 0 <= other <= 16:
-                other = bytes(_bchr(CScriptOp.encode_op_n(other)))
+                other = bytes([CScriptOp.encode_op_n(other)])
             elif other == -1:
-                other = bytes(_bchr(OP_1NEGATE))
+                other = bytes([OP_1NEGATE])
             else:
                 other = CScriptOp.encode_op_pushdata(bitcoin.core._bignum.bn2vch(other))
         elif isinstance(other, (bytes, bytearray)):
@@ -572,7 +562,7 @@ def raw_iter(self):
         i = 0
         while i < len(self):
             sop_idx = i
-            opcode = _bord(self[i])
+            opcode = self[i]
             i += 1
 
             if opcode > OP_PUSHDATA4:
@@ -588,21 +578,21 @@ def raw_iter(self):
                     pushdata_type = 'PUSHDATA1'
                     if i >= len(self):
                         raise CScriptInvalidError('PUSHDATA1: missing data length')
-                    datasize = _bord(self[i])
+                    datasize = self[i]
                     i += 1
 
                 elif opcode == OP_PUSHDATA2:
                     pushdata_type = 'PUSHDATA2'
                     if i + 1 >= len(self):
                         raise CScriptInvalidError('PUSHDATA2: missing data length')
-                    datasize = _bord(self[i]) + (_bord(self[i+1]) << 8)
+                    datasize = self[i] + (self[i+1] << 8)
                     i += 2
 
                 elif opcode == OP_PUSHDATA4:
                     pushdata_type = 'PUSHDATA4'
                     if i + 3 >= len(self):
                         raise CScriptInvalidError('PUSHDATA4: missing data length')
-                    datasize = _bord(self[i]) + (_bord(self[i+1]) << 8) + (_bord(self[i+2]) << 16) + (_bord(self[i+3]) << 24)
+                    datasize = self[i] + (self[i+1] << 8) + (self[i+2] << 16) + (self[i+3] << 24)
                     i += 4
 
                 else:
@@ -676,9 +666,9 @@ def is_p2sh(self):
         Note that this test is consensus-critical.
         """
         return (len(self) == 23 and
-                _bord(self[0]) == OP_HASH160 and
-                _bord(self[1]) == 0x14 and
-                _bord(self[22]) == OP_EQUAL)
+                self[0] == OP_HASH160 and
+                self[1] == 0x14 and
+                self[22] == OP_EQUAL)
 
     def is_witness_scriptpubkey(self):
         """Returns true if this is a scriptpubkey signaling segregated witness data.
@@ -747,7 +737,7 @@ def has_canonical_pushes(self):
                 if op > OP_16:
                     continue
 
-                elif op < OP_PUSHDATA1 and op > OP_0 and len(data) == 1 and _bord(data[0]) <= 16:
+                elif op < OP_PUSHDATA1 and op > OP_0 and len(data) == 1 and data[0] <= 16:
                     # Could have used an OP_n code, rather than a 1-byte push.
                     return False
 
@@ -770,7 +760,7 @@ def has_canonical_pushes(self):
     def is_unspendable(self):
         """Test if the script is provably unspendable"""
         return (len(self) > 0 and
-                _bord(self[0]) == OP_RETURN)
+                self[0] == OP_RETURN)
 
     def is_valid(self):
         """Return True if the script is valid, False otherwise
@@ -1018,7 +1008,7 @@ def SignatureHash(script, txTo, inIdx, hashtype, amount=None, sigversion=SIGVERS
             serialize_outputs = txTo.vout[inIdx].serialize()
             hashOutputs = bitcoin.core.Hash(serialize_outputs)
 
-        f = _BytesIO()
+        f = BytesIO()
         f.write(struct.pack("<i", txTo.nVersion))
         f.write(hashPrevouts)
         f.write(hashSequence)